1
|
Fan S, Wei J, Xu X, Yan R, Li Q, Liu Y, Huang Y, Wang Y, Fan G, Zhang L. Treatment of chromium-containing sludge using sintering and ironmaking combined technology: A risk-reducing strategy for environmental impact. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 359:120986. [PMID: 38696849 DOI: 10.1016/j.jenvman.2024.120986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 04/03/2024] [Accepted: 04/20/2024] [Indexed: 05/04/2024]
Abstract
The efficient, safe and eco-friendly disposal of the chromium-containing sludge (CCS) has attracted an increasing concern. In this study, Co-processing of CCS was developed via employing sintering and ironmaking combined technology for its harmless disposal and resource utilization. Crystalline phase and valence state transformation of chromium (Cr), technical feasibility assessment, leaching risk, characteristics of sintered products, and pollutant release during CCS co-processing were investigated through a series of laboratory-scale sintering pot experiments and large scale industrial trials. The results showed that the content of Cr(VI) in sintered products first increased then decreased with increasing temperature ranges of 300 °C-800 °C, and reached a maximum of 2189.64 mg/kg at 500 °C. 99.99% of Cr(VI) can be reduced to Cr(III) at above 1000 °C, which was attributed to the transformation of the Cr(VI)-containing crystalline phases (such as, MgCrO4 and CaCrO4) to the (Mg, Fe2+)(Cr, Al, Fe3+)2O4. The industrial trial results showed that adding 0.5 wt‰ CCS to sintering feed did not have adverse effects on the properties of the sintered ore and the plant's operating stability. The tumbler index of sinter was above 78% and the leaching concentrations of TCr (0.069 mg/L) was significantly lower than the Chinese National Standard of 1.0 mg/L (GB5085.3-2007). The TCr contents of sintering dust and blast furnace gas (BFG) scrubbing water were less than 0.19 wt‰ and 0.11 mg/L, respectively, which was far below the regulatory limit (1.5 mg/L, GB13456-2012). The mass balance evaluation results indicated that at least 89.9% of the Cr in the CCS migrated into the molten iron in the blast furnace (BF), which became a useful supplement to the molten iron. This study provided a new perspective strategy for the safe disposal and resource utilization of CCS in iron and steel industry.
Collapse
Affiliation(s)
- Shengxuan Fan
- School of Chemistry and Environmental Engineering, Wuhan Polytechnic University, Wuhan, 430023, China
| | - Jinchao Wei
- Zhongye Changtian International Engineering Co., Ltd., Changsha, 410205, China; National Engineering Research Center of Sintering and Pelletizing Equipment System, Changsha, 410205, China
| | - Xiaorong Xu
- School of Chemistry and Environmental Engineering, Wuhan Polytechnic University, Wuhan, 430023, China
| | - Ran Yan
- School of Chemistry and Environmental Engineering, Wuhan Polytechnic University, Wuhan, 430023, China
| | - Qian Li
- Zhongye Changtian International Engineering Co., Ltd., Changsha, 410205, China; National Engineering Research Center of Sintering and Pelletizing Equipment System, Changsha, 410205, China
| | - Ying Liu
- R&D Center of Wuhan Iron and Steel Company, Wuhan, 430080, China
| | - Yanjun Huang
- School of Chemistry and Environmental Engineering, Wuhan Polytechnic University, Wuhan, 430023, China
| | - Yi Wang
- School of Chemistry and Environmental Engineering, Wuhan Polytechnic University, Wuhan, 430023, China.
| | - Guozhi Fan
- School of Chemistry and Environmental Engineering, Wuhan Polytechnic University, Wuhan, 430023, China
| | - Lei Zhang
- School of Chemistry and Environmental Engineering, Wuhan Polytechnic University, Wuhan, 430023, China.
| |
Collapse
|
2
|
Thery G, Juillot F, Calmels D, Bollaert Q, Meyer M, Quiniou T, David M, Jourand P, Ducousso M, Fritsch E, Landrot G, Morin G, Quantin C. Heating effect on chromium speciation and mobility in Cr-rich soils: A snapshot from New Caledonia. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 922:171037. [PMID: 38373451 DOI: 10.1016/j.scitotenv.2024.171037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 02/14/2024] [Accepted: 02/15/2024] [Indexed: 02/21/2024]
Affiliation(s)
- Gaël Thery
- Géosciences Paris-Saclay, GEOPS, UMR CNRS 8148, Université Paris Saclay, 91405 Orsay Cedex, France; Institut de Recherche pour le Développement, IRD, ERL 206 IMPMC, 98848 Nouméa Cedex, New Caledonia
| | - Farid Juillot
- Institut de Recherche pour le Développement, IRD, ERL 206 IMPMC, 98848 Nouméa Cedex, New Caledonia; Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, UMR 7590 CNRS, Sorbonne Université, MNHN, IRD, 75005 Paris Cedex 05, France.
| | - Damien Calmels
- Géosciences Paris-Saclay, GEOPS, UMR CNRS 8148, Université Paris Saclay, 91405 Orsay Cedex, France
| | - Quentin Bollaert
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, UMR 7590 CNRS, Sorbonne Université, MNHN, IRD, 75005 Paris Cedex 05, France
| | - Michael Meyer
- Institut des Sciences Exactes et Appliquées, ISEA, EA, Université de la Nouvelle-Calédonie, Nouméa, New Caledonia
| | - Thomas Quiniou
- Institut des Sciences Exactes et Appliquées, ISEA, EA, Université de la Nouvelle-Calédonie, Nouméa, New Caledonia
| | - Magali David
- Institut de Recherche pour le Développement, IRD, ERL 206 IMPMC, 98848 Nouméa Cedex, New Caledonia
| | - Philippe Jourand
- Laboratoire des Symbioses Tropicales et Mediterranéennes (LSTM), Université Montpellier, UMR IRD 040, UMR CIRAD 082, Campus International de Baillarguet, Montpellier, France
| | - Marc Ducousso
- Laboratoire des Symbioses Tropicales et Mediterranéennes (LSTM), Université Montpellier, UMR IRD 040, UMR CIRAD 082, Campus International de Baillarguet, Montpellier, France
| | - Emmanuel Fritsch
- Géosciences Paris-Saclay, GEOPS, UMR CNRS 8148, Université Paris Saclay, 91405 Orsay Cedex, France; Institut de Recherche pour le Développement, IRD, ERL 206 IMPMC, 98848 Nouméa Cedex, New Caledonia
| | - Gautier Landrot
- Synchrotron SOLEIL, l'Orme les Merisiers, Saint Aubin, France
| | - Guillaume Morin
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, UMR 7590 CNRS, Sorbonne Université, MNHN, IRD, 75005 Paris Cedex 05, France
| | - Cécile Quantin
- Géosciences Paris-Saclay, GEOPS, UMR CNRS 8148, Université Paris Saclay, 91405 Orsay Cedex, France
| |
Collapse
|
3
|
Guo S, Wang H, Liu X, Zhang Z, Liu Y. Approaches for the Treatment and Resource Utilization of Electroplating Sludge. MATERIALS (BASEL, SWITZERLAND) 2024; 17:1707. [PMID: 38612220 PMCID: PMC11013125 DOI: 10.3390/ma17071707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 04/03/2024] [Accepted: 04/04/2024] [Indexed: 04/14/2024]
Abstract
The disposal of electroplating sludge (ES) is a major challenge for the sustainable development of the electroplating industry. ESs have a significant environmental impact, occupying valuable land resources and incurring high treatment costs, which increases operational expenses for companies. Additionally, the high concentration of hazardous substances in ES poses a serious threat to both the environment and human health. Despite extensive scholarly research on the harmless treatment and resource utilization of ES, current technology and processes are still unable to fully harness its potential. This results in inefficient resource utilization and potential environmental hazards. This article analyzes the physicochemical properties of ES, discusses its ecological hazards, summarizes research progress in its treatment, and elaborates on methods such as solidification/stabilization, heat treatment, wet metallurgy, pyrometallurgy, biotechnology, and material utilization. It provides a comparative summary of different treatment processes while also discussing the challenges and future development directions for technologies aimed at effectively utilizing ES resources. The objective of this text is to provide useful information on how to address the issue of ES treatment and promote sustainable development in the electroplating industry.
Collapse
Affiliation(s)
- Song Guo
- School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China; (S.G.); (H.W.)
| | - Huimin Wang
- School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China; (S.G.); (H.W.)
| | - Xiaoming Liu
- School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China; (S.G.); (H.W.)
- State Key Laboratory of Advanced Metallurgy, School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Zengqi Zhang
- School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China; (S.G.); (H.W.)
| | - Yu Liu
- China International Engineering Consulting Corporation, Beijing 100048, China;
| |
Collapse
|
4
|
Li Z, Yu D, Wang X, Liu X, Xu Z, Wang Y. A novel strategy of tannery sludge disposal - converting into biochar and reusing for Cr(VI) removal from tannery wastewater. J Environ Sci (China) 2024; 138:637-649. [PMID: 38135427 DOI: 10.1016/j.jes.2023.04.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 04/13/2023] [Accepted: 04/13/2023] [Indexed: 12/24/2023]
Abstract
Tannery sludge with high chromium content has been identified as hazardous solid waste due to its potential toxic effects. The safety disposal and valorization of the tannery sludge remains a challenge. In this study, the chromium stabilization mechanism was systematically investigated during chromium-rich tannery sludge was converted to biochar and the removal performance of the sludge biochar (SBC) for Cr(VI) from tannery wastewater was also investigated. The results showed that increase in pyrolysis temperature was conductive to the stabilization of Cr and significant reduction of the proportion of Cr(VI) in SBC. It was confirmed that the stabilization of chromium mainly was attributed to the embedding of chromium in the C matrix and the transformation of the chromium-containing substances from the amorphous Cr(OH)3 to the crystalline state, such as (FeMg)Cr2O5. The biochar presented high adsorption capacity of Cr(VI) at low pH and the maximal theoretical adsorption capacity of SBC produced at 800°C can reach 352 mg Cr(VI)/g, the process of which can be well expressed by Langmuir adsorption isotherm and pseudo second order model. The electrostatic effect and reduction reaction were dominantly responsible for the Cr(VI) adsorption by SBC800. Overall, this study provided a novel strategy for the harmless disposal and resource utilization for the solid waste containing chromium in leather industry.
Collapse
Affiliation(s)
- Zhiwei Li
- CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Di Yu
- CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Xingdong Wang
- CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Xuejiao Liu
- CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Zhen Xu
- CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Yin Wang
- CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; Zhejiang Key Laboratory of Urban Environmental Processes and Pollution Control, CAS Haixi Industrial Technology Innovation Center in Beilun, Ningbo 315830, China; Key Laboratory of Urban Environment and Health, Ningbo Observation and Research Station, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
| |
Collapse
|
5
|
Zhang A, Liu J, Yang Y, Li Y. Insights into chromium removal mechanism by Ca-based sorbents from flue gas. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:168928. [PMID: 38049006 DOI: 10.1016/j.scitotenv.2023.168928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 11/14/2023] [Accepted: 11/25/2023] [Indexed: 12/06/2023]
Abstract
Chromium is a typical toxic pollution in sewage sludge incineration flue gas. Cr removal from flue gas is a challenge due to the high toxicity and valence variability of chromium. Ca-based sorbents, including CG-CaO, CA-CaO, and CCi-CaO, were developed for Cr capture by calcining calcium D-gluconate monohydrate, calcium acetate hydrate, and calcium citrate tetrahydrate, respectively. CG-CaO, CA-CaO, and CCi-CaO exhibit better Cr removal performance than traditional CaO. CA-CaO shows superior Cr adsorption ability due to the large BET surface area and pore volume. The Cr adsorption efficiency of CA-CaO is up to 94.79 % at 1000 °C. XRD and XPS results reveal that the adsorbed Cr contains Cr(III) and Cr(VI), and exists in the form of CaCr2O4 and CaCrO4. Cr adsorption on Ca-based sorbents is mainly controlled by adsorption and oxidation mechanism. The adsorption process of Cr on different Ca-based sorbents was described by four typical adsorption kinetic models. For CaO and CG-CaO, pseudo-first order model and Elovich model are suitable for the description of Cr adsorption. For CA-CaO and CCi-CaO, pseudo-second order model, Elovich model and Weber and Morris model fit well with the experimental values of Cr adsorption, suggesting that Cr adsorption on CA-CaO and CCi-CaO is controlled by a combined mechanism of chemisorption and intraparticle diffusion. The saturated adsorption capacity of CaO, CG-CaO, CA-CaO and CCi-CaO are evaluated to be 39.77, 48.98, 102.22 and 104.52 mg/g, respectively. The effects of incineration flue gas components on Cr adsorption were also explored. O2 shows no obvious influence on Cr adsorption over CA-CaO. HCl, SO2, NO and CO2 can inhibit Cr adsorption because of the competitive adsorption, and the inhibitory effect of SO2 is the strongest.
Collapse
Affiliation(s)
- Aijia Zhang
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Jing Liu
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
| | - Yingju Yang
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Yemei Li
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| |
Collapse
|
6
|
Zhao Y, Zhang C, Ma L, Li J, Tan P, Fang Q, Chen G. Effects of temperature on the migration behaviour of arsenic and chromium in tannery sludge under CO 2 gasification. JOURNAL OF HAZARDOUS MATERIALS 2024; 461:132663. [PMID: 37783141 DOI: 10.1016/j.jhazmat.2023.132663] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 08/24/2023] [Accepted: 09/26/2023] [Indexed: 10/04/2023]
Abstract
To reduce heavy metals (HMs) contamination from tannery sludge, this study investigated the migration behaviour of arsenic (As) and chromium (Cr) at 700-900 °C using CO2 gasification. The HMs enrichment results showed that As contents of ash decreased (6.42→1.87 mg/kg) while Cr contents increased (41.40→78.24 mg/kg) over 700-900 °C. More Si-O bonds and fewer Ca-O bonds with increasing temperature in ash primarily determined this migration behaviour of HMs. Meanwhile, the proportions of toxic As(III) and Cr(VI) declined from 96.02% and 64.26-76.96% and 21.24%, forming As(0) and Cr(III) with less toxicity. This reduction was conducted via two pathways: (i) carbon reduced As(III)/Cr(VI) and (ii) carbon reduced Fe(II)/Fe(III) to Fe(0), then Fe(0) reduced As(III)/Cr(VI) assisted with carbon via Fe(0)→Fe(II)→Fe(III). However, free calcium ions oxidized As(0)/Cr(III) to As(III)/Cr(VI) at 700 ○C. At higher temperatures, silicate glass conversion of ash immobilized free calcium ions and barely oxidized HMs. Furthermore, this study identified the positive effect of increasing temperature on enhancing the stability of HMs in ash by transforming bioavailable HMs into non-bioavailable HMs, which decreased the leaching toxicity and environmental risk. Regarding HMs emissions control and cold gas efficiency, CO2 gasification treatment of tannery sludge is most effective at 800 °C.
Collapse
Affiliation(s)
- Yan Zhao
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Cheng Zhang
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
| | - Lun Ma
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Junchen Li
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Peng Tan
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Qingyan Fang
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Gang Chen
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| |
Collapse
|
7
|
Wang X, Wang H, Zhang Z, Li J, Zhang H, Wang W, Mao Y, Song Z. Calcination of sewage sludge-based sulphoaluminate cement clinker: Mineral formation mechanism and heavy metal transition behaviors. ENVIRONMENTAL RESEARCH 2023; 237:116986. [PMID: 37633637 DOI: 10.1016/j.envres.2023.116986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 07/19/2023] [Accepted: 08/23/2023] [Indexed: 08/28/2023]
Abstract
Utilizing sewage sludge (SS) to calcinate sulphoaluminate cement (SAC) is a promising technology for low-carbon transition of cement industry, but the unclear effects of SS-contained heavy metals limit the application of this technology. In this study, the effects of SS addition on the calcination of SAC clinker and the transformation of heavy metals were studied from the aspects of mineral phase change, microstructure evolution and heavy metal speciation respectively, covering the mineral formation temperature 900-1250 °C. The results show that the added SS will reduce the formation temperature and change the reaction pathways of mineral phases. When the content of SS increases from 10% to 25%, the compositions of mesophases CaO·Al2O3 and 4CaO·2SiO2·CaSO4 increase by 6.33% and 9.73%, respectively. Meanwhile, the formation of minerals will solidify Zn, Ni, Mn, Cu, Cr, and convert them into a more stable fraction (residual fraction), indicating a lower probability to harm the environment. Moreover, heavy metals present different migration behaviors. After calcination, Mn migrates from SS to 4CaO·Al2O3·Fe2O3 (52.48%), while Zn prefers to enter 3CaO·3Al2O3·CaSO4 (43.74%) and 4CaO·Al2O3·Fe2O3 (38.06%). This study offers new insights into the mineral formation mechanism and heavy metal transition behaviors of sewage sludge-based SAC.
Collapse
Affiliation(s)
- Xujiang Wang
- National Engineering Laboratory for Reducing Emissions from Coal Combustion, Jinan, Shandong, 250061, China; School of Energy and Power Engineering, Shandong University, Jinan, Shandong, 250061, China
| | - Haohao Wang
- National Engineering Laboratory for Reducing Emissions from Coal Combustion, Jinan, Shandong, 250061, China; School of Energy and Power Engineering, Shandong University, Jinan, Shandong, 250061, China
| | - Ziliang Zhang
- National Engineering Laboratory for Reducing Emissions from Coal Combustion, Jinan, Shandong, 250061, China; School of Energy and Power Engineering, Shandong University, Jinan, Shandong, 250061, China
| | - Jingwei Li
- National Engineering Laboratory for Reducing Emissions from Coal Combustion, Jinan, Shandong, 250061, China; School of Energy and Power Engineering, Shandong University, Jinan, Shandong, 250061, China.
| | - Hongzhi Zhang
- School of Qilu Transportation, Shandong University, Jinan, Shandong, 250061, China
| | - Wenlong Wang
- National Engineering Laboratory for Reducing Emissions from Coal Combustion, Jinan, Shandong, 250061, China; School of Energy and Power Engineering, Shandong University, Jinan, Shandong, 250061, China
| | - Yanpeng Mao
- National Engineering Laboratory for Reducing Emissions from Coal Combustion, Jinan, Shandong, 250061, China; School of Energy and Power Engineering, Shandong University, Jinan, Shandong, 250061, China
| | - Zhanlong Song
- National Engineering Laboratory for Reducing Emissions from Coal Combustion, Jinan, Shandong, 250061, China; School of Energy and Power Engineering, Shandong University, Jinan, Shandong, 250061, China
| |
Collapse
|
8
|
Ghezzi L, Mugnaioli E, Perchiazzi N, Duce C, Pelosi C, Zamponi E, Pollastri S, Campanella B, Onor M, Abdellatief M, Franceschini F, Petrini R. Hexavalent chromium release over time from a pyrolyzed Cr-bearing tannery sludge. Sci Rep 2023; 13:16283. [PMID: 37770570 PMCID: PMC10539330 DOI: 10.1038/s41598-023-43579-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 09/26/2023] [Indexed: 09/30/2023] Open
Abstract
Pyrolysis in an inert atmosphere is a widely applied route to convert tannery wastes into reusable materials. In the present study, the Cr(III) conversion into the toxic hexavalent form in the pyrolyzed tannery waste referred to as KEU was investigated. Ageing experiments and leaching tests demonstrated that the Cr(III)-Cr(VI) inter-conversion occurs in the presence of air at ambient temperature, enhanced by wet environmental conditions. Microstructural analysis revealed that the Cr-primary mineral assemblage formed during pyrolysis (Cr-bearing srebrodolskite and Cr-magnetite spinel) destabilized upon spray water cooling in the last stage of the process. In the evolution from the higher to the lower temperature mineralogy, Cr is incorporated into newly formed CrOOH flakes which likely react in air forming extractable Cr(VI) species. This property transforms KEU from an inert waste to a hazardous material when exposed to ordinary ambient conditions.
Collapse
Affiliation(s)
- Lisa Ghezzi
- Department of Earth Science, University of Pisa, Via S. Maria 53, 56126, Pisa, Italy.
| | - Enrico Mugnaioli
- Department of Earth Science, University of Pisa, Via S. Maria 53, 56126, Pisa, Italy
| | - Natale Perchiazzi
- Department of Earth Science, University of Pisa, Via S. Maria 53, 56126, Pisa, Italy
| | - Celia Duce
- Department of Chemistry, University of Pisa, via G. Moruzzi 13, 56124, Pisa, Italy
| | - Chiara Pelosi
- Department of Chemistry, University of Pisa, via G. Moruzzi 13, 56124, Pisa, Italy
| | - Erika Zamponi
- Department of Earth Science, University of Pisa, Via S. Maria 53, 56126, Pisa, Italy
| | - Simone Pollastri
- Elettra - Sincrotrone Trieste, in AREA Science Park, Basovizza, 34149, Trieste, Italy
| | - Beatrice Campanella
- Institute of Chemistry of Organometallic Compounds (ICCOM-CNR) Pisa, Via G. Moruzzi 1, 56124, Pisa, Italy
| | - Massimo Onor
- Institute of Chemistry of Organometallic Compounds (ICCOM-CNR) Pisa, Via G. Moruzzi 1, 56124, Pisa, Italy
| | | | - Fabrizio Franceschini
- Environmental Protection Agency of Tuscany (ARPAT), Via Vittorio Veneto, 56127, Pisa, Italy
| | - Riccardo Petrini
- Department of Earth Science, University of Pisa, Via S. Maria 53, 56126, Pisa, Italy
| |
Collapse
|
9
|
Madhusoodhanan R, Paramashivan SS, Mohan S, Rajeshwari VB. Study on the soluble and insoluble fume and hexavalent chromium emitted from a new covered electrode with micro and nano sized-sodium and potassium titanate-based flux. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:95550-95565. [PMID: 37552445 DOI: 10.1007/s11356-023-29079-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Accepted: 07/27/2023] [Indexed: 08/09/2023]
Abstract
The present study discusses the effect of the addition of nano-sized arc stabilizing materials on fume emissions and its solubility characteristics. Micro and nano-sized sodium/potassium titanates were added to the SMAW electrode flux as a substitute for the conventional sodium and potassium silicate compounds. The total and soluble metal concentration of fumes from the newly developed electrodes were estimated and compared with that of commercially available electrodes. The estimation of fume formation rate and breathing zone concentration of fumes followed the ISO 15011-1 and ISO 10882-1 standard. An average 50% reduction in the soluble fraction of fumes was observed from the electrodes containing micro-sized potassium-titanate compounds, and the reduction was further improved by 60% when nano-sodium titanate was added to the flux. Whereas, the reduction in soluble metal concentration for potassium titanate coated electrodes were 45% and 55%, in that order, for their micro and nano-structured forms. The soluble fraction of hexavalent chromium from the electrodes containing 100% nano sodium/potassium titanates was reduced up to 50% in each impactor stage. The inclusion of nano-sized sodium titanate in the flux resulted in a reduction in fume formation rate up to 55% and breathing zone concentration of fumes by 58% compared to the conventional sodium silicate coated electrodes. The electrode assaying 100% nano-potassium titanate showed a reduction of 59% in fume formation rate and 61% in breathing zone concentration compared to that of conventional potassium silicate-coated electrodes.
Collapse
Affiliation(s)
- Rahul Madhusoodhanan
- Industrial Safety Engineering Lab, Department of Mechanical Engineering, National Institute of Technology, Tiruchirappalli, India
| | | | - Sreejith Mohan
- Industrial Safety Engineering Lab, Department of Mechanical Engineering, National Institute of Technology, Tiruchirappalli, India
- Centre for Combustion and Emission Studies (CCES), National Institute of Technology, Tiruchirappalli, India
| | - Vishnu B Rajeshwari
- Industrial Safety Engineering Lab, Department of Mechanical Engineering, National Institute of Technology, Tiruchirappalli, India
| |
Collapse
|
10
|
Liu H, Wang Y, Chen J. Transformation of Zn and Cr during co-combustion of sewage sludge and coals: influence of coal and steam. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:98351-98361. [PMID: 37606773 DOI: 10.1007/s11356-023-28907-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 07/17/2023] [Indexed: 08/23/2023]
Abstract
Combustion experiments of sewage sludge (SS) blended with low-rank coal were conducted through a drop tube furnace (DTF) to explore the effects of low-rank coal type, blending ratio, and steam on the transformation of Zn and Cr. The results showed that the retention rates of Zn and Cr in ash increased from 24.35% and 71.49% for sludge combustion alone to 53.77% and 117.49%, respectively, for coal blended to SS with a mass ratio of 7:3. The greater the proportion of low-rank coal in the fuel, the greater the residual rate of heavy metals in the ash. Meanwhile, rapid diffusion of vapor occupied adsorption sites on metal mineral surfaces, reducing the retention of Zn and Cr in the co-combustion ash. The leaching toxicity analysis of ash showed that the co-combustion ash of SS with coal was free from leaching toxicity hazards in simulated scenarios. The extraction rate of Zn in co-combustion ash increased from 90.72% with hydrothermal acid leaching to 95.46% with microwave-assisted in 2 mol/L H2SO4 extract. The extraction rate of Cr in hydrothermal acid leaching was 62.80%, which was much higher than that in microwave-assisted extraction (31.76%).
Collapse
Affiliation(s)
- Hao Liu
- National Engineering Laboratory for Reducing Emissions From Coal Combustion, Engineering Research Center of Environmental Thermal Technology of Ministry of Education, Shandong Key Laboratory of Energy Carbon Reduction and Resource Utilization, School of Energy and Power Engineering, Shandong University, Jinan, 250061, Shandong, China
| | - Yajun Wang
- National Engineering Laboratory for Reducing Emissions From Coal Combustion, Engineering Research Center of Environmental Thermal Technology of Ministry of Education, Shandong Key Laboratory of Energy Carbon Reduction and Resource Utilization, School of Energy and Power Engineering, Shandong University, Jinan, 250061, Shandong, China
| | - Juan Chen
- National Engineering Laboratory for Reducing Emissions From Coal Combustion, Engineering Research Center of Environmental Thermal Technology of Ministry of Education, Shandong Key Laboratory of Energy Carbon Reduction and Resource Utilization, School of Energy and Power Engineering, Shandong University, Jinan, 250061, Shandong, China.
| |
Collapse
|
11
|
Yang Y, Shi S, Zhu C, Chen X, Hao Y, Yan L, Li J, Chen X, Chen B, Ma X, Ma H. Immobilization of chromium in real tannery sludge via heat treatment with coal fly ash. CHEMOSPHERE 2023; 335:139180. [PMID: 37302500 DOI: 10.1016/j.chemosphere.2023.139180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 06/07/2023] [Accepted: 06/08/2023] [Indexed: 06/13/2023]
Abstract
The secure and harmless disposal for Cr-bearing tannery sludge (Cr-TS) has attracted an increasing concern, due to potentially adverse effect on ecosystem and human health. A greener alternative method about "waste treatment with waste" for thermally stabilizing real Cr-TS was developed via employing coal fly ash (CA) as dopants in this research. The co-heat treatment of Cr-TS and CA was carried out at the temperature range of 600-1200 °C to investigate the oxidation of Cr(III), immobilization of chromium and leaching risk of the sintered products, and the mechanism of chromium immobilization was further explored. The results indicate that the doping of CA can significantly inhibit the oxidation of Cr(III) and immobilize chromium by incorporating chromium into spinel and uvarovite microcrystal. At the temperature higher than 1000 °C, most of chromium can be converted into stable crystalline phases. Furthermore, a prolonged leaching test was conducted to study the leaching toxicity of chromium in sintered products, indicating that leaching content of chromium is much less than the regulatory limit. This process is a feasible and promising alternative for immobilization of chromium in Cr-TS. The research findings are supposed to offer a theoretical foundation and strategy choice for thermal stabilization of chromium, as well as safety and harmless disposal of Cr-containing hazardous waste.
Collapse
Affiliation(s)
- Yonglin Yang
- Shaanxi Key Laboratory of Low Metamorphic Coal Clean Utilization, School of Chemistry and Chemical Engineering, Yulin University, Yulin, 719000, PR China; School of Environmental Science and Engineering, Shaanxi University of Science & Technology, Xi'an, 710021, PR China
| | - Shuaige Shi
- Shaanxi Key Laboratory of Low Metamorphic Coal Clean Utilization, School of Chemistry and Chemical Engineering, Yulin University, Yulin, 719000, PR China
| | - Chao Zhu
- School of Environmental Science and Engineering, Shaanxi University of Science & Technology, Xi'an, 710021, PR China
| | - Xiangping Chen
- School of Environmental Science and Engineering, Shaanxi University of Science & Technology, Xi'an, 710021, PR China
| | - Yongyong Hao
- School of Environmental Science and Engineering, Shaanxi University of Science & Technology, Xi'an, 710021, PR China
| | - Long Yan
- Shaanxi Key Laboratory of Low Metamorphic Coal Clean Utilization, School of Chemistry and Chemical Engineering, Yulin University, Yulin, 719000, PR China.
| | - Jian Li
- Shaanxi Key Laboratory of Low Metamorphic Coal Clean Utilization, School of Chemistry and Chemical Engineering, Yulin University, Yulin, 719000, PR China
| | - Xiaodong Chen
- Shaanxi Key Laboratory of Low Metamorphic Coal Clean Utilization, School of Chemistry and Chemical Engineering, Yulin University, Yulin, 719000, PR China
| | - Bi Chen
- Shaanxi Key Laboratory of Low Metamorphic Coal Clean Utilization, School of Chemistry and Chemical Engineering, Yulin University, Yulin, 719000, PR China
| | - Xiangrong Ma
- Shaanxi Key Laboratory of Low Metamorphic Coal Clean Utilization, School of Chemistry and Chemical Engineering, Yulin University, Yulin, 719000, PR China
| | - Hongrui Ma
- School of Environmental Science and Engineering, Shaanxi University of Science & Technology, Xi'an, 710021, PR China.
| |
Collapse
|
12
|
Li M, Hu Y, Zhou N, Wang S, Sun F. Hydrothermal treatment coupled with pyrolysis and calcination for stabilization of electroplating sludge: Speciation transformation and environmental risk of heavy metals. JOURNAL OF HAZARDOUS MATERIALS 2022; 438:129539. [PMID: 35999723 DOI: 10.1016/j.jhazmat.2022.129539] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 06/30/2022] [Accepted: 07/04/2022] [Indexed: 06/15/2023]
Abstract
Electroplating sludge (ES) produced from treatment of electroplating wastewater is a hazardous waste due to its high content of heavy metals (HMs). This study investigates the feasibility of hydrothermal treatment (HT) coupled with pyrolysis and calcination as a method for safe disposal of ES by immobilizing the soluble fractions of target HMs in ES. The HMs before and after thermal processing were characterized to better understand their speciation transformation and environmental risk. Results showed that over 74% of HMs in ES were accumulated in the resulted solid residues and the other HMs were mainly released into the gas phase. The immobilization rates of HMs from the soluble fractions (F1 and F2) to stable fractions (F3 and F4) after the separate HT and HT coupled pyrolysis and calcination were up to 82.4%, 78.0% and 80.5%, respectively. HT coupled with high-temperature calcination outperformed HT in terms of converting low volatile HMs to stable residual speciations, such as Cu and Ni. HT coupled with pyrolysis showed the best effect in reducing the environmental risks of Cr. In terms of ecological risk index, the separate HT demonstrated an ideal immobilization effect and toxicity reduction for soluble fractions of HMs, especially for Zn and Mn.
Collapse
Affiliation(s)
- Mingzhe Li
- Institute of Thermal and Power Engineering, Zhejiang University of Technology, Liuhe Road 288#, 310023 Hangzhou, China
| | - Yanjun Hu
- Institute of Thermal and Power Engineering, Zhejiang University of Technology, Liuhe Road 288#, 310023 Hangzhou, China; Zhejiang Carbon Neutral Innovation Institute, Zhejiang University of Technology, Chaowang Road 18#, 310024 Hangzhou, China.
| | - Nan Zhou
- Institute of Thermal and Power Engineering, Zhejiang University of Technology, Liuhe Road 288#, 310023 Hangzhou, China
| | - Shurong Wang
- State Key Laboratory of Clean Energy Utilization, Zhejiang University, Zheda Road 38#, 310027 Hangzhou, China.
| | - Feifan Sun
- Institute of Thermal and Power Engineering, Zhejiang University of Technology, Liuhe Road 288#, 310023 Hangzhou, China
| |
Collapse
|
13
|
Shen D, Bao Q, Qiu J, Gu F, Wu Z, Wu M, Guo W, Long Y. Effect of calcium oxide on chromium solidification during the melting of hazardous waste incineration fly ash. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 317:115475. [PMID: 35662047 DOI: 10.1016/j.jenvman.2022.115475] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 05/29/2022] [Accepted: 05/31/2022] [Indexed: 06/15/2023]
Abstract
Thermal treatment technology considerably affects the harmlessness of fly ash (FA), but highly toxic heavy metals, such as Cr, attract considerable attention. In this study, we investigated the influence of CaO dosage at 600°C-1200 °C on the curing effect of Cr during FA thermal treatment based on the combination effect of CaO. Static, dynamic, and continuous sequential leachings were performed for the sintered products. Results showed that the leaching concentration of Cr decreased by approximately 91% when CaO dosage was 8.57%, and the difference in the residual state was the main reason for the difference in the leaching behavior of Cr. The proportion of the residual state in the sintered products increased from 35.16% to 64.01%. The transition between Cr2O3, Cr5O12, and CaCr2O4 is the fundamental reason for the leaching behavior of Cr and the change in the residual state. This study provides a scientific basis for preventing and controlling heavy metal pollution and optimizing environmental supervision in the FA thermal treatment process.
Collapse
Affiliation(s)
- Dongsheng Shen
- Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, China; Instrumental Analysis Center of Zhejiang Gongshang University, Hangzhou, 310018, China
| | - Qiqi Bao
- Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, China
| | - Junjian Qiu
- Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, China
| | - Foquan Gu
- Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, China
| | - Zixiao Wu
- Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, China
| | - Minjin Wu
- Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, China
| | - Wenxin Guo
- Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, China
| | - Yuyang Long
- Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, China; Instrumental Analysis Center of Zhejiang Gongshang University, Hangzhou, 310018, China.
| |
Collapse
|
14
|
Chen H, Zhang X, Geng S, Song S, Wang Y. Modulating the Electronic Structure of RuO 2 through Cr Solubilizing for Improved Oxygen Evolution Reaction. SMALL METHODS 2022; 6:e2200636. [PMID: 35879051 DOI: 10.1002/smtd.202200636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 06/19/2022] [Indexed: 06/15/2023]
Abstract
Hydrogen production from water electrolysis is important for the sustainable development of hydrogen energy. Nevertheless, the naturally torpid property of anodic oxygen evolution reaction (OER) kinetics and poor stability of its catalysts significantly restrict the development of electrochemical water splitting. Here, a Ru0.6 Cr0.4 O2 electrocatalyst is synthesized, which reveals excellent OER activity with the overpotential of only 195 mV at 10 mA cm-2 and excellent stability with the potential increase of merely 5.3 mV after 20 h continuous OER test in acidic media. Theoretical calculations reveal that the solubilizing of Cr into RuO2 could adjust the electron distribution, making the d-band center of Ru far away from the Fermi level. This behavior reduces the binding energy with Ru and O and accelerates the rate-determining step of OER (i.e., the formation of *OOH), thereby increasing OER activity. In addition, the incorporation of Cr increases the energy of oxygen defect formation and reduces the participation of lattice oxygen, thus improving the stability of the catalyst. This research furnishes a feasible policy for the development of highly active and stable catalysts in acidic media by regulating the electronic structure of RuO2 .
Collapse
Affiliation(s)
- Haixin Chen
- The Key Lab of Low-Carbon Chemistry and Energy Conservation of Guangdong Province, PCFM, School of Chemical Engineering and Technology, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou, 510275, China
| | - Xiaofeng Zhang
- The Key Lab of Low-Carbon Chemistry and Energy Conservation of Guangdong Province, PCFM, School of Chemical Engineering and Technology, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou, 510275, China
| | - Shipeng Geng
- The Key Lab of Low-Carbon Chemistry and Energy Conservation of Guangdong Province, PCFM, School of Chemical Engineering and Technology, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou, 510275, China
| | - Shuqin Song
- The Key Lab of Low-Carbon Chemistry and Energy Conservation of Guangdong Province, PCFM, School of Chemical Engineering and Technology, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou, 510275, China
| | - Yi Wang
- The Key Lab of Low-Carbon Chemistry and Energy Conservation of Guangdong Province, PCFM, School of Chemical Engineering and Technology, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou, 510275, China
| |
Collapse
|
15
|
Immobilization of Metals in Fired Clay Brick Incorporated with Aluminium-Rich Electroplating Sludge: Properties and Leaching Analysis. SUSTAINABILITY 2022. [DOI: 10.3390/su14148732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Electroplating sludge is the hazardous waste discarded from the plating and extractive metallurgical process which can only be disposed of at a secured landfill. In this study, the physical and mechanical properties, as well as metal leaching analysis, of fired clay brick incorporated with electroplating sludge (0%, 2%, 4%, 6%, 8% and 10%) were determined. The physical and mechanical properties of bricks, such as firing shrinkage, dry density, initial rate of absorption, water absorption and compressive strength, were tested according to British standard 3921:1985 and British standard EN772:1. Furthermore, the metal leachability was determined by using the toxicity characteristic leaching procedure (TCLP) method 1311. The results show that the utilization of an electroplating-sludge brick up to 4% could enhance physical and mechanical properties, such as reducing the water absorption from 18.3% to 16.1% and increasing the compressive strength from 25.6 MPa to 41.6 MPa. The result also show that 4% of aluminium-rich electroplating sludge incorporated into the brick is the most suitable amount, as it leached less metal concentration and complied with USEPA standards. The metals which were most present in the electroplating sludge (aluminium and iron) drastically reduced from 193,000 ppm to 0.1372 ppm and from 4160 ppm to 0.144 ppm, respectively. Therefore, the electroplating sludge could be fully utilized in the fired clay brick as an alternative to producing low-cost building materials whilst decreasing the levels of disposal of metal sludge on the secured landfill.
Collapse
|
16
|
Huang Q, Wang Q, Liu X, Li X, Zheng J, Gao H, Li L, Xu W, Wang S, Xie M, Xiao Y, Lin Z. Effective separation and recovery of Zn, Cu, and Cr from electroplating sludge based on differential phase transformation induced by chlorinating roasting. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 820:153260. [PMID: 35065102 DOI: 10.1016/j.scitotenv.2022.153260] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 01/15/2022] [Accepted: 01/15/2022] [Indexed: 06/14/2023]
Abstract
Heavy metals in electroplating sludge (ES) are usually amorphous and easily released in the environment. Especially for the ES containing multiple heavy metals, owing to the complex composition and lack of effective disposal method, it has been storage for a long time. In order to avoid environmental pollution, effective treatment methods are very urgent and necessary. Here, chlorinating roasting method was developed to enlarge the phase difference of heavy metals to fulfill the utilization of ES containing multiple heavy metals (Zn, Cr, and Cu). When CaCl2 was used as additive, Zn and Cu were volatilized to the gas phase, while Cr was oxidized to Cr(V)/(VI) and retained in the solid phase with readily leachable state. The recovery percentage of Zn, Cu, and Cr can reach 99%, 98%, and 96% respectively by chlorinating roasting for 4 h at 1000 °C with the CaCl2 addition proportion of 100%. After further extraction and purification, the purity of Cr and Zn can reach 92% and 99% respectively. Moreover, the mechanism of the differential phase transformation induced by chlorinating roasting was analyzed by the method of thermodynamics and kinetics. The kinetic reaction equation of the ZnCl2 and CuCl2 volatilization process can be described by phase boundary reaction and the function is G(α) = 1-(1-α)1/3. This work provides a simple and effective method for the treatment of ES containing multiple heavy metals.
Collapse
Affiliation(s)
- Qiuyun Huang
- School of Metallurgy and Environment, Central South University, Changsha, Hunan 410083, PR China; Chinese National Engineering Research Center for Control &Treatment of Heavy Metal Pollution, Changsha, Hunan 410083, PR China
| | - Qingwei Wang
- School of Metallurgy and Environment, Central South University, Changsha, Hunan 410083, PR China; Chinese National Engineering Research Center for Control &Treatment of Heavy Metal Pollution, Changsha, Hunan 410083, PR China
| | - Xueming Liu
- School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, Guangdong 510006, PR China
| | - Xiaoqin Li
- School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, Guangdong 510006, PR China
| | - Jiayi Zheng
- School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, Guangdong 510006, PR China
| | - Huiqin Gao
- School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, Guangdong 510006, PR China
| | - Li Li
- School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, Guangdong 510006, PR China.
| | - Wenbin Xu
- Dongjiang Environmental Co. Ltd., Shenzhen, Guangdong 518000, PR China
| | - Shi Wang
- Dongjiang Environmental Co. Ltd., Shenzhen, Guangdong 518000, PR China
| | - Mengqin Xie
- Baoshan Iron and Steel Co. Ltd., Shanghai 201900, PR China
| | - Yongli Xiao
- Baoshan Iron and Steel Co. Ltd., Shanghai 201900, PR China
| | - Zhang Lin
- School of Metallurgy and Environment, Central South University, Changsha, Hunan 410083, PR China; Chinese National Engineering Research Center for Control &Treatment of Heavy Metal Pollution, Changsha, Hunan 410083, PR China
| |
Collapse
|
17
|
Jiang H, Wang J, Zhang W, Hu L, Mao L. Oxidation and reduction reactions of (Al/Fe xCr 1-x) 2O 3 caused by CaO during thermal treatment of solid waste containing Cr. ENVIRONMENTAL RESEARCH 2022; 204:112356. [PMID: 34822857 DOI: 10.1016/j.envres.2021.112356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 11/04/2021] [Accepted: 11/06/2021] [Indexed: 06/13/2023]
Abstract
Solid solutions of (AlxCr1-x)2O3 and (FexCr1-x)2O3 are predominant compounds containing Cr in solid waste and are frequently formed during thermal treatment of solid waste. (AlxCr1-x)2O3 and (FexCr1-x)2O3 have superior thermomechanical properties and excellent corrosion resistance. However, oxidation and reduction reactions of the Cr in these solid solutions seriously affect their chemical stabilities and the environmental risks posed by the final products. In this study, first the reaction behaviors of (AlxCr1-x)2O3 and (FexCr1-x)2O3 at high temperatures were analyzed and whether the incorporation of Cr(III) in solid solutions can prevent Cr(III) from being oxidized was determined. Both (AlxCr1-x)2O3 and (FexCr1-x)2O3 without the presence of CaO exhibit good thermal stability at high temperatures. However, the participation of CaO induces Cr(III) oxidation in (AlxCr1-x)2O3 and (FexCr1-x)2O3 at 500-1000 °C. Cr(III) oxidation in these solid solutions is accompanied by the formation of CaCrO4 and Fe2O3 or Al2O3. Al2O3 combines with CaCrO4 and further forms a more stable Cr(VI) compound (e.g., Ca4Al6O12CrO4). While Fe2O3 combines with CaCrO4 at 1000-1200 °C. This is accompanied by the formation of CaCr2O4 and CaFe2O4, which effectively promotes the reduction of Cr(VI). Moreover, part of the CaCr2O4 transforms into a more stable phase (i.e., FeCr2O4) at 1200-1300 °C. Although the incorporation of Cr(III) in these solid solutions cannot prevent Cr(III) oxidation completely at high temperatures, the Cr(III) oxidation in these solid solutions is still suppressed compared with Cr2O3. The results of this study provide further insights into the oxidation and reduction reactions of Cr-hosting compounds during thermal treatment of solid waste.
Collapse
Affiliation(s)
- Haohao Jiang
- School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, PR China
| | - Jia Wang
- School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, PR China
| | - Wenyi Zhang
- School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, PR China
| | - Linchao Hu
- School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, PR China
| | - Linqiang Mao
- School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, PR China.
| |
Collapse
|
18
|
Kim J, Shin J, Paek SM, Park DS, Kim SJ. Formation, thermal redox reaction and crystal structure of δ-CaCr2O4. J SOLID STATE CHEM 2022. [DOI: 10.1016/j.jssc.2021.122669] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
19
|
Liu X, Jiang H, Wang J, Zhang W, Hu L, Peng M, Mao L. Oxidation reaction behavior of Cr-hosting spinels during heating of solid wastes containing Cr. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 800:149634. [PMID: 34426319 DOI: 10.1016/j.scitotenv.2021.149634] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 07/28/2021] [Accepted: 08/09/2021] [Indexed: 06/13/2023]
Abstract
Cr-hosting spinels are frequently formed during heating of solid wastes containing multiple metals, and its oxidation reaction (Cr(III) → Cr(VI)) is closely related with the toxicity of products. This study examined the reaction behaviors of Cr-hosting spinels (ZnCr2O4, CuCr2O4 and NiCr2O4) at high temperature and proposed possible oxidation mechanism. Cr-hosting spinels alone usually exhibit good thermal stability at high temperature. However, CaO can trigger the oxidation of Cr(III) in Cr-hosting spinels at 500-900 °C and ZnCr2O4 is easier to be oxidized than NiCr2O4 and CuCr2O4 at same condition. The oxidation of Cr-hosting spinels is accompanied with the formation of CaCrO4 and divalent metal oxides (ZnO, NiO and CuO). The broken and rebuilding of CrO bonds are key steps for Cr-hosting spinels oxidation, blocking the combination of free Cr with Ca and O atoms maybe more effective approach for suppressing Cr(III) oxidation. Furthermore, CaO can trigger the reduction of CaCrO4 into a new Cr(V) compound (Ca5(CrO4)3O0.5) at 900-1200 °C. As the temperature rising to 1300 °C, CuO reacts with CaCrO4 to form CuCrO2, in which Cu(II) and Cr(VI) are reduced into Cu(I) and Cr(III) respectively. This study provided some new knowledge for the reaction behavior of Cr-hosting spinels when solid wastes containing Cr were treated at high temperature.
Collapse
Affiliation(s)
- Xiao Liu
- School of Environmental and Safety Engineering, Changzhou University, Changzhou 213164, PR China
| | - Haohao Jiang
- School of Environmental and Safety Engineering, Changzhou University, Changzhou 213164, PR China
| | - Jia Wang
- School of Environmental and Safety Engineering, Changzhou University, Changzhou 213164, PR China
| | - Wenyi Zhang
- School of Environmental and Safety Engineering, Changzhou University, Changzhou 213164, PR China
| | - Linchao Hu
- School of Environmental and Safety Engineering, Changzhou University, Changzhou 213164, PR China
| | - Mingguo Peng
- School of Environmental and Safety Engineering, Changzhou University, Changzhou 213164, PR China
| | - Linqiang Mao
- School of Environmental and Safety Engineering, Changzhou University, Changzhou 213164, PR China.
| |
Collapse
|
20
|
Ye M, Li G, Liang J, Liao X, Ren J, Fen X, Qian W, Li L, Sun S. A high-efficiency process for the separation of chromium and aluminum from waste aluminum sludge with a high chromium content using a combined oxidation and dispersion process. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2020.118083] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
21
|
Combination of Thermal, Hydrometallurgical and Electrochemical Tannery Waste Treatment for Cr(III) Recovery. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11020532] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A combination of thermal (500–750 °C in air) and hydrometallurgical (acidic) treatments have been applied to dried tannery sludge, resulting in the initial conversion of Cr(III) to Cr(VI) and its subsequent leaching as wastewater with high Cr(VI) concentration content (3000–6000 mg/L), presenting an extraction efficiency over 90%. The optimal electrochemical conditions for the subsequent Cr(VI) reduction with respect to acid concentration and acid kind were established by applying appropriate rotating disc electrode (RDE) experiments, using a glassy carbon (GC) electrode, and found to be equal or higher than 0.5 M H2SO4 (for the respective Cr(III) concentration range studied). The result from leaching Cr(VI) wastewater was further treated in small electrochemical bench-scale reactor for its conversion back to Cr(III) form, potentially reusable in the tanning industry. Ti-based anodes and a reticulated vitreous carbon (RVC) cathode were used to treat small (350–800 mL) samples in batch, as well as in batch-recirculation prototype electrochemical reactors, under the application of constant current or appropriately applied potential to achieve Cr(VI) conversion/reduction efficiency over 95%.
Collapse
|
22
|
Xu T, Liao N, Xu Y, Nath M, Li Y, Chen Y, Sang S. In situ detoxification and mechanical properties of Al2O3-Cr2O3-CaO castables with zeolite. Ann Ital Chir 2021. [DOI: 10.1016/j.jeurceramsoc.2020.08.060] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
23
|
Gong H, Huang Y, Hu H, Shi M, Fu B, Luo C, Yan D, Yao H. The potential oxidation characteristics of CaCr 2O 4 during coal combustion with solid waste in a fluidized bed boiler: A thermogravimetric analysis. CHEMOSPHERE 2021; 263:127974. [PMID: 32828060 DOI: 10.1016/j.chemosphere.2020.127974] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 08/04/2020] [Accepted: 08/06/2020] [Indexed: 06/11/2023]
Abstract
CaCr2O4 (Cr (III)), mainly generated through the decomposition of CaCrO4 (Cr (VI)), is a significant intermediate for toxic Cr (VI) formation during solid fuel combustion. In this study, the formation, oxidation and sulfation kinetics of CaCr2O4 were analyzed to forecast the potential of CaCr2O4 oxidation during co-firing of coal and solid waste in a circulating fluidized bed boiler. The results indicated that the formation and oxidation of CaCr2O4 were fitted to a single step nucleation and growth model while CaCr2O4 sulfation was fitted to a shrinking core model. CaCr2O4 formation through CaCrO4 decomposition was favored in oxygen-lean atmosphere and considerably suppressed in the presence of oxygen. In contrast, CaCr2O4 oxidation was mainly determined by the contacts between CaCr2O4 and CaSO4/CaO, which influenced not only oxidation rates but also the product species. Moreover, the oxidation reactivity of CaCr2O4 was higher in the presence of CaO than that of CaSO4. On the other hand, CaCr2O4 sulfation can occur more easily than CaCr2O4 oxidation, the reaction rate of which was deeply affected by sulfate product layer. Findings in this study suggested that spraying calcium in furnace for desulphurization may increase the risk of CaCr2O4 oxidation. Measures including the adjustment of Ca/S ratio in blended fuel (with added limestone) and operating conditions (such as temperature and local atmosphere) in co-firing system could be taken to control CaCr2O4 formation and oxidation.
Collapse
Affiliation(s)
- Hongyu Gong
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Yongda Huang
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Hongyun Hu
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.
| | - Mengya Shi
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Biao Fu
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Cong Luo
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Dahai Yan
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Hong Yao
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| |
Collapse
|
24
|
Mao L, Wang J, Zeng M, Zhang W, Hu L, Peng M. Temperature dependent reduction of Cr(VI) to Cr(V) aroused by CaO during thermal treatment of solid waste containing Cr(VI). CHEMOSPHERE 2021; 262:127924. [PMID: 32805661 DOI: 10.1016/j.chemosphere.2020.127924] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/31/2020] [Accepted: 08/03/2020] [Indexed: 06/11/2023]
Abstract
Cr(VI) compounds at high temperature usually tend to decompose and reduce into Cr(III) due to thermodynamically instability for Cr(VI). This study found Cr(VI) could be reduced into Cr(V) instead of Cr(III) in the presence of CaO during heating solid waste containing Cr(VI). CaCrO4 is prepared and mixed with CaO as simulated solid waste containing Cr(VI). It was found that CaCrO4 reacted with CaO and formed a new product Ca5(CrO4)3O0.5 at temperature range of 800 and 1000 °C. The valence state of Cr in Ca5(CrO4)3O0.5 is determined to be +5 b y XPS analysis, and the color for new formed Cr(V) is observed in green, similar to Cr(III) compounds. The temperature and CaO are two keys to arouse the reduction reaction of Cr(VI) into Cr(V). In particular, the reduction of Cr(VI) into Cr(V) is strongly depended on temperature (800-1000 °C), this reaction can be balanced within 10 min, while prolonging sintering time has little help for promoting the reduction of Cr(VI) to Cr(V). Additionally, it was found Cr(V) can keep stable and not be re-oxidized into Cr(VI) at 800-1000 °C. Above results offers some new understanding and knowledge about the formation of Cr(V) in presence of much CaO or CaCO3 during heating solid waste containing Cr(VI).
Collapse
Affiliation(s)
- Linqiang Mao
- School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, PR China.
| | - Jia Wang
- School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, PR China
| | - Man Zeng
- School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, PR China
| | - Wenyi Zhang
- School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, PR China.
| | - Linchao Hu
- School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, PR China
| | - Mingguo Peng
- School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, PR China
| |
Collapse
|
25
|
Du Y, Wen Y, Fan H, Qi J, Zhang S, Li G. Elimination of Cr(VI) from chromium slag with poplar lignin by electrochemical treatment in sulfuric acid solution. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:29441-29450. [PMID: 32436097 DOI: 10.1007/s11356-020-09289-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 05/13/2020] [Indexed: 06/11/2023]
Abstract
In this paper, we proposed a novel method to eliminate nocuous Cr(VI) from chromium slag with poplar lignin by electrochemical treatment in sulfuric acid solution. In this electrochemical process, self-made Ti/SnO2-Sb anode and graphite cathode were applied, and the oxidative degradation of lignin proceeded simultaneously with the reduction of Cr(VI) in one pot. The influences of pivotal factors on electrocatalytic redox efficiency were investigated, such as chromium slag concentration, lignin concentration, current density, sulfuric acid concentration, and reaction time. The results showed that the elimination rate of Cr(VI) in chromium slag was 97.16 ± 1.13% and the total yield of lignin degradation products reached 93.78 g/kg lignin under the optimal conditions. X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS), and UV-visible spectrophotometer studies confirmed that most of the Cr(VI) ions were reduced to Cr(III) ions with the aid of lignin, and a small amount of Cr(VI) ions were adsorbed by lignin residue. Importantly, this method provides a typical example of "waste control by waste", which is treating waste chromium slag with waste lignin that can be an effective way to eliminate Cr(VI).
Collapse
Affiliation(s)
- Yabo Du
- School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin, 300130, People's Republic of China
| | - Yeqian Wen
- School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin, 300130, People's Republic of China.
| | - Hongxian Fan
- School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin, 300130, People's Republic of China
| | - Jian Qi
- School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin, 300130, People's Republic of China
| | - Songmei Zhang
- School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin, 300130, People's Republic of China
| | - Gang Li
- School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin, 300130, People's Republic of China.
| |
Collapse
|
26
|
Yang Y, Ma H, Chen X, Zhu C, Li X. Effect of incineration temperature on chromium speciation in real chromium-rich tannery sludge under air atmosphere. ENVIRONMENTAL RESEARCH 2020; 183:109159. [PMID: 32028182 DOI: 10.1016/j.envres.2020.109159] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 01/17/2020] [Accepted: 01/20/2020] [Indexed: 06/10/2023]
Abstract
As a hazardous waste, the disposal of chromium enriched tannery sludge has attracted increasing public concern due to its potential adverse risks towards the environment. And incineration is considered to be an effective method to stabilize heavy metals, like Cr, in solid phase during tannery sludge treatment. In this study, real chromium enriched tannery sludge without pre-treatment was incinerated at 300°C-1200 °C under air atmosphere to investigate the transformation of chromium speciation. Here detailed thermal behavior, phase transformation and chromium speciation were characterized by TG-DSC, XRD and XPS, respectively. Experimental results show that content of Cr(VI) increases gradually with the increase of temperature from 300 °C to 500 °C and reaches a maximal level of 46% total Cr at 500 °C, with different Cr(VI) species of CaCrO4, MgCrO4 and Cr5O12. However, the content of Cr(VI) decreases gradually with the further increase of temperature, with only about 5% Cr(VI) at high temperature of 1200 °C, due to formation of Cr(III) species of Cr2O3 crystallite and MgCr2O4 spinel. Besides, a growing number of hexagonally shaped flake-like crystallite Cr2O3 can be discovered from characterization results of XRD and SEM. Finally, the reduction of CaCrO4 to Cr2O3 in the presence of SiO2 is thermodynamically feasible over 700 °C, indicating possible transformation of Cr(VI) to Cr(III) through controlled incineration temperature.
Collapse
Affiliation(s)
- Yonglin Yang
- School of Environmental Science and Engineering, Shaanxi University of Science & Technology, Xi'an, 710021, PR China; School of Chemical Engineering, Shenmu Vocational & Technical College, Shenmu, 719300, PR China
| | - Hongrui Ma
- School of Environmental Science and Engineering, Shaanxi University of Science & Technology, Xi'an, 710021, PR China.
| | - Xiangping Chen
- School of Environmental Science and Engineering, Shaanxi University of Science & Technology, Xi'an, 710021, PR China.
| | - Chao Zhu
- School of Environmental Science and Engineering, Shaanxi University of Science & Technology, Xi'an, 710021, PR China
| | - Xiaojie Li
- School of Chemistry and Chemical Engineering, Shaanxi University of Science & Technology, Xi'an, 710021, PR China
| |
Collapse
|
27
|
Mengke-Li, Yuting-Zhuo, Yuting-Hu, Shuzhen-Li, Liang-Hu, Hui-Zhong, Zhiguo-He. Exploration on the bioreduction mechanism of Cr(Ⅵ) by a gram-positive bacterium: Pseudochrobactrum saccharolyticum W1. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 184:109636. [PMID: 31536849 DOI: 10.1016/j.ecoenv.2019.109636] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 08/30/2019] [Accepted: 09/03/2019] [Indexed: 06/10/2023]
Abstract
Bioremediation of chromium (Cr(Ⅵ)) contaminations has been widely reported, but the research on its removal mechanism is still scarce. Studies on Cr(Ⅵ) removal by strains affiliated to genus Pseudochobactrum revealed the Cr(Ⅵ) efficiency removal through the reduction of Cr(Ⅵ) to Cr(Ⅲ). However, the location of Cr(Ⅵ) reduction reaction and exact mechanism are still unspecified. In this work, a Gram-positive bacterial strain, Pseudochrobactrum saccharolyticum W1 (P. saccharolyticum W1) was isolated and tested to remove approximately 53.7% of Cr(Ⅵ) (initial concentration was 200 mg L-1) from the MSM medium. Analysis of SEM-EDS and TEM-EDS indicated that chromium-containing particles precipitated both on the cell surface and in the cytoplasm. Batch experiments indicated that the heat-treated bacterial cells almost had no ability to remove Cr(Ⅵ) from solution, while the resting cells could remove 62.0% of Cr(Ⅵ) at the initial concentration of 10 mg L-1. Additionally, at this concentration, 64.8% and 70.8% of Cr(Ⅵ) was reduced by cell envelope components and intracellular soluble substances after 6 h, respectively. These results suggested that the removal of Cr(Ⅵ) by P. saccharolyticum W1 was through direct reduction, which occurred on both cell envelop and cytoplasm. The results also showed that cytoplasm was the main site for Cr(Ⅵ) reduction compared to the cell envelop. Further analysis of FTIR and XPS verified that C-H, C-C, CO, C-OH and C-O-C groups of cells involved in correlation with chromium during Cr(Ⅵ) reduction. The study offered an insight into the Cr(VI) reduction mechanism of P. saccharolyticum W1.
Collapse
|
28
|
Structural and radiation shielding properties of chromium oxide doped borosilicate glass. Radiat Phys Chem Oxf Engl 1993 2019. [DOI: 10.1016/j.radphyschem.2018.11.012] [Citation(s) in RCA: 82] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
29
|
Mao L, Wu Y, Zhang W, Huang Q. The reuse of waste glass for enhancement of heavy metals immobilization during the introduction of galvanized sludge in brick manufacturing. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 231:780-787. [PMID: 30415171 DOI: 10.1016/j.jenvman.2018.10.120] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Revised: 10/15/2018] [Accepted: 10/31/2018] [Indexed: 06/09/2023]
Abstract
The mixing of galvanized sludge in fired clay brick manufacturing has been regarded as an alternative approach for the consumption of galvanized sludge. Decreasing the surface area and porosity of fired brick definitely lowers the risk of heavy metal release. In this study, a novel method is proposed to reduce the surface area and porosity of bricks and promote heavy metal immobilization by adding waste glass. The introduction of waste glass enhanced the physical and mechanical performances of fired clay bricks and resulted in an increase in bulk density and compressive strength and a decrease in water absorption. Microstructure analysis showed that the texture of the bricks turned from porous to smooth and homogeneous due to the introduction of waste glass. Porosity analysis showed that surface area and pore volume of fired brick were substantially reduced. When the added waste glass amount exceeded 15 wt%, the heavy metal concentrations that leached from bricks containing 10 wt% galvanized sludge fired at 950 °C met the regulatory requirement. These results demonstrate that waste glass can be reused to enhance the stabilization/solidification of heavy metals, during the mixing of hazardous waste in bricks and ceramics manufacturing process.
Collapse
Affiliation(s)
- Linqiang Mao
- School of Environmental and Safety Engineering, Changzhou University, Changzhou 213164, PR China; Department of Mining Engineering, West Virginia University, Morgantown, 26506, United States.
| | - Yunqiu Wu
- School of Environmental and Safety Engineering, Changzhou University, Changzhou 213164, PR China
| | - Wenyi Zhang
- School of Environmental and Safety Engineering, Changzhou University, Changzhou 213164, PR China
| | - Qingqing Huang
- Department of Mining Engineering, West Virginia University, Morgantown, 26506, United States
| |
Collapse
|
30
|
Chromium-ruthenium oxide solid solution electrocatalyst for highly efficient oxygen evolution reaction in acidic media. Nat Commun 2019; 10:162. [PMID: 30635581 PMCID: PMC6329788 DOI: 10.1038/s41467-018-08144-3] [Citation(s) in RCA: 177] [Impact Index Per Article: 35.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 12/14/2018] [Indexed: 11/09/2022] Open
Abstract
The development of active, acid-stable and low-cost electrocatalysts for oxygen evolution reaction is urgent and challenging. Herein we report an Iridium-free and low ruthenium-content oxide material (Cr0.6Ru0.4O2) derived from metal-organic framework with remarkable oxygen evolution reaction performance in acidic condition. It shows a record low overpotential of 178 mV at 10 mA cm-2 and maintains the excellent performance throughout the 10 h chronopotentiometry test at a constant current of 10 mA cm-2 in 0.5 M H2SO4 solution. Density functional theory calculations further revealed the intrinsic mechanism for the exceptional oxygen evolution reaction performance, highlighting the influence of chromium promoter on the enhancement in both activity and stability.
Collapse
|
31
|
Hu H, Shi M, Yang Y, Liu H, Xu M, Shen J, Yao H. Further Insight into the Formation and Oxidation of CaCr 2O 4 during Solid Fuel Combustion. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:2385-2391. [PMID: 29390188 DOI: 10.1021/acs.est.7b05538] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The control of toxic chromate (Cr6+) formation is still a significant challenge in solid fuel combustion. In particular, the mechanism of chromium transformation from Cr3+ to chromate or other unoxidized forms remains unclear. The present study confirms the formation of a significant unoxidized Cr-containing compound CaCr2O4(Cr3+) during solid fuel combustion. Experiments were conducted, for the first time, to clarify the mechanism of CaCr2O4 oxidation, which is quite different from Cr2O3 oxidation. The findings demonstrate that CaCr2O4 was formed at temperatures above 1200 K, through rapid decomposition of CaCrO4 or slow and direct interaction between CaO and Cr2O3. Compared to Cr2O3, CaCr2O4 could be oxidized at lower temperatures under the influence of free CaO. In the absence of free CaO, the oxidation of CaCr2O4 was minimal; however, in the presence of CaSO4, calcium in the form of CaCr2O4 participated in the oxidation of CaCr2O4. Thus, chromium in the form of CaCr2O4 was more likely to be oxidized when CaCr2O4-containing fly ash was reheated. Fortunately, CaCr2O4 showed slight basicity on the surface, allowing it to react with acidic gases. Accordingly, measures were proposed to suppress the oxidation of CaCr2O4 by stimulating the reactions between CaCr2O4 and acidic substances, like SO2 and Si/Al-compounds. These compounds competed with chromium at high temperatures to react with calcium in the fly ash and in CaCr2O4. As a result, the unoxidized chromium was transformed into highly stable Cr2O3 or Ca3Cr2 (SiO4)3.
Collapse
Affiliation(s)
- Hongyun Hu
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology , Wuhan 430074, P. R. China
| | - Mengya Shi
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology , Wuhan 430074, P. R. China
| | - Yuhan Yang
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology , Wuhan 430074, P. R. China
| | - Huan Liu
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology , Wuhan 430074, P. R. China
- Department of New Energy Science and Engineering, School of Energy and Power Engineering, Huazhong University of Science and Technology , Wuhan 430074, P. R. China
| | - Mian Xu
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology , Wuhan 430074, P. R. China
| | - Junhao Shen
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology , Wuhan 430074, P. R. China
| | - Hong Yao
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology , Wuhan 430074, P. R. China
- Department of New Energy Science and Engineering, School of Energy and Power Engineering, Huazhong University of Science and Technology , Wuhan 430074, P. R. China
| |
Collapse
|
32
|
Oves M, Khan MS, Qari HA. Ensifer adhaerens for heavy metal bioaccumulation, biosorption, and phosphate solubilization under metal stress condition. J Taiwan Inst Chem Eng 2017. [DOI: 10.1016/j.jtice.2017.08.026] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
33
|
Ng ZG, Lim JW, Isa MH, Pasupuleti VR, Yunus NM, Lee KC. Adsorptive removal of hexavalent chromium using sawdust: Enhancement of biosorption and bioreduction. SEP SCI TECHNOL 2017. [DOI: 10.1080/01496395.2017.1296868] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Zhung-Gia Ng
- School of Chemical Sciences, Universiti Sains Malaysia, Penang, Malaysia
| | - Jun-Wei Lim
- Department of Fundamental and Applied Sciences, Universiti Teknologi PETRONAS, Seri Iskandar, Perak Darul Ridzuan, Malaysia
| | - Mohamed Hasnain Isa
- Department of Civil and Environmental Engineering, Universiti Teknologi PETRONAS, Seri Iskandar, Perak Darul Ridzuan, Malaysia
| | - Visweswara Rao Pasupuleti
- Institute of Food Security and Sustainable Agriculture, Universiti Malaysia Kelantan, Jeli Campus, Jeli, Kelantan, Malaysia
| | - Normawati M. Yunus
- Department of Fundamental and Applied Sciences, Universiti Teknologi PETRONAS, Seri Iskandar, Perak Darul Ridzuan, Malaysia
| | - Kean-Chuan Lee
- Department of Fundamental and Applied Sciences, Universiti Teknologi PETRONAS, Seri Iskandar, Perak Darul Ridzuan, Malaysia
| |
Collapse
|
34
|
Liao CZ, Tang Y, Lee PH, Liu C, Shih K, Li F. Detoxification and immobilization of chromite ore processing residue in spinel-based glass-ceramic. JOURNAL OF HAZARDOUS MATERIALS 2017; 321:449-455. [PMID: 27669386 DOI: 10.1016/j.jhazmat.2016.09.035] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 08/24/2016] [Accepted: 09/14/2016] [Indexed: 05/25/2023]
Abstract
A promising strategy for the detoxification and immobilization of chromite ore processing residue (COPR) in a spinel-based glass-ceramic matrix is reported in this study. In the search for a more chemically durable matrix for COPR, the most critical crystalline phase for Cr immobilization was found to be a spinel solid solution with a chemical composition of MgCr1.32Fe0.19Al0.49O4. Using Rietveld quantitative X-ray diffraction analysis, we identified this final product is with the phases of spinel (3.5wt.%), diopside (5.2wt.%), and some amorphous contents (91.2wt.%). The partitioning ratio of Cr reveals that about 77% of the Cr was incorporated into the more chemically durable spinel phase. The results of Cr K-edge X-ray absorption near-edge spectroscopy show that no Cr(VI) was observed after conversion of COPR into a glass-ceramic, which indicates successful detoxification of Cr(VI) into Cr(III) in the COPR-incorporated glass-ceramic. The leaching performances of Cr2O3 and COPR-incorporated glass-ceramic were compared with a prolonged acid-leaching test, and the results demonstrate the superiority of the COPR-incorporated glass-ceramic matrix in the immobilization of Cr. The overall results suggest that the use of affordable additives has potential in more reliably immobilizing COPR with a spinel-based glass-ceramic for safer disposal of this hazardous waste.
Collapse
Affiliation(s)
- Chang-Zhong Liao
- Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control, Guangdong Institute of Eco-Environmental and Soil Sciences, Guangzhou 510650, PR China; Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong Special Administrative Region, PR China
| | - Yuanyuan Tang
- School of Environmental Science and Engineering, South University of Science and Technology of China, Shenzhen 518055, PR China
| | - Po-Heng Lee
- Department of Civil & Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong Special Administrative Region, PR China
| | - Chengshuai Liu
- Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control, Guangdong Institute of Eco-Environmental and Soil Sciences, Guangzhou 510650, PR China; State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550009, PR China.
| | - Kaimin Shih
- Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong Special Administrative Region, PR China.
| | - Fangbai Li
- Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control, Guangdong Institute of Eco-Environmental and Soil Sciences, Guangzhou 510650, PR China
| |
Collapse
|
35
|
Mao L, Gao B, Deng N, Liu L, Cui H. Oxidation behavior of Cr(III) during thermal treatment of chromium hydroxide in the presence of alkali and alkaline earth metal chlorides. CHEMOSPHERE 2016; 145:1-9. [PMID: 26650573 DOI: 10.1016/j.chemosphere.2015.11.053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 10/29/2015] [Accepted: 11/16/2015] [Indexed: 06/05/2023]
Abstract
The oxidation behavior of Cr(III) during the thermal treatment of chromium hydroxide in the presence of alkali and alkaline earth metal chlorides (NaCl, KCl, MgCl2, and CaCl2) was investigated. The amounts of Cr(III) oxidized at various temperatures and heating times were determined, and the Cr-containing species in the residues were characterized. During the transformation of chromium hydroxide to Cr2O3 at 300 °C approximately 5% of the Cr(III) was oxidized to form intermediate compounds containing Cr(VI) (i.e., CrO3), but these intermediates were reduced to Cr2O3 when the temperature was above 400 °C. Alkali and alkaline earth metals significantly promoted the oxidation of Cr(III) during the thermal drying process. Two pathways were involved in the influences the alkali and alkaline earth metals had on the formation of Cr(VI). In pathway I, the alkali and alkaline earth metals were found to act as electron transfer agents and to interfere with the dehydration process, causing more intermediate Cr(VI)-containing compounds (which were identified as being CrO3 and Cr5O12) to be formed. The reduction of intermediate compounds to Cr2O3 was also found to be hindered in pathway I. In pathway II, the alkali and alkaline earth metals were found to contribute to the oxidation of Cr(III) to form chromates. The results showed that the presence of alkali and alkaline earth metals significantly increases the degree to which Cr(III) is oxidized during the thermal drying of chromium-containing sludge.
Collapse
Affiliation(s)
- Linqiang Mao
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210046, PR China
| | - Bingying Gao
- College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, PR China
| | - Ning Deng
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210046, PR China
| | - Lu Liu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210046, PR China
| | - Hao Cui
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210046, PR China.
| |
Collapse
|