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Zhou X, Wang D, Liu C, Jing G, Lv B, Wang D. Enhancing CO 2 capture of an aminoethylethanolamine-based non-aqueous absorbent by using tertiary amine as a proton-transfer mediator: From performance to mechanism. J Environ Sci (China) 2024; 140:146-156. [PMID: 38331496 DOI: 10.1016/j.jes.2023.06.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 06/04/2023] [Accepted: 06/04/2023] [Indexed: 02/10/2024]
Abstract
Non-aqueous absorbents (NAAs) have attracted increasing attention for CO2 capture because of their great energy-saving potential. Primary diamines which can provide high CO2 absorption loading are promising candidates for formulating NAAs but suffer disadvantages in regenerability. In this study, a promising strategy that using tertiary amines (TAs) as proton-transfer mediators was proposed to enhance the regenerability of an aminoethylethanolamine (AEEA, diamine)/dimethyl sulfoxide (DMSO) (A/D) NAA. Surprisingly, some employed TAs such as N,N-diethylaminoethanol (DEEA), N,N,N',N'',N''-pentamethyldiethylenetriamine (PMDETA), 3-dimethylamino-1-propanol (3DMA1P), and N,N-dimethylethanolamine (DMEA) enhanced not only the regenerability of the A/D NAA but also the CO2 absorption performance. Specifically, the CO2 absorption loading and cyclic loading were increased by about 12.7% and 15.5%-22.7%, respectively. The TA-enhanced CO2 capture mechanism was comprehensively explored via nuclear magnetic resonance technique and quantum chemical calculations. During CO2 absorption, the TA acted as an ultimate proton acceptor for AEEA-zwitterion and enabled more AEEA to form carbamate species (AEEACOO-) to store CO2, thus enhancing CO2 absorption. For CO2 desorption, the TA first provided protons directly to AEEACOO- as a proton donor; moreover, it functioned as a proton carrier and facilitated the low-energy step-wise proton transfer from protonated AEEA to AEEACOO-. Consequently, the presence of TA made it easier for AEEACOO- to obtain protons to decompose, resulting in enhanced CO2 desorption. In a word, introducing the TA as a proton-transfer mediator into the A/D NAA enhanced both the CO2 absorption performance and the regenerability, which was an efficient way to "kill two birds with one stone".
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Affiliation(s)
- Xiaobin Zhou
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, China; The Guangxi Key Laboratory of Theory and Technology for Environmental Pollution Control, Guilin University of Technology, Guilin 541004, China
| | - Dan Wang
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, China
| | - Chao Liu
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, China
| | - Guohua Jing
- College of Chemical Engineering, Huaqiao University, Xiamen 361021, China.
| | - Bihong Lv
- College of Chemical Engineering, Huaqiao University, Xiamen 361021, China
| | - Dunqiu Wang
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, China; The Guangxi Key Laboratory of Theory and Technology for Environmental Pollution Control, Guilin University of Technology, Guilin 541004, China.
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2
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Yuxi L, Peng L, Jun Z, Can W, Longwen C, Dengfeng Y, Quanming R, Xiaoliang L, Mingli F, Suib SL, Daiqi Y. Electrospun Ce-Mn oxide as an efficient catalyst for soot combustion: Ce-Mn synergy, soot-catalyst contact, and catalytic oxidation mechanism. Chemosphere 2023; 334:138995. [PMID: 37211160 DOI: 10.1016/j.chemosphere.2023.138995] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 05/17/2023] [Accepted: 05/18/2023] [Indexed: 05/23/2023]
Abstract
Increasing the contact efficiency and improving the intrinsic activity are two effective strategies to obtain efficient catalysts for soot combustion. Herein, the electrospinning method is used to synthesize fiber-like Ce-Mn oxide with a strong synergistic effect. The slow combustion of PVP in precursors and highly soluble manganese acetate in spinning solution facilitates the formation of fibrous Ce-Mn oxides. The fluid simulation clearly indicates that the slender and uniform fibers provide more interwoven macropores to capture soot particles than the cubes and spheres do. Accordingly, electrospun Ce-Mn oxide exhibits better catalytic activity than reference catalysts, including Ce-Mn oxides by co-precipitation and sol-gel methods. The characterizations suggest that Mn3+ substitution into fluorite-type CeO2 enhances the reducibility through the acceleration of Mn-Ce electron transfer, improves the lattice oxygen mobility by weakening the Ce-O bonds, and induces oxygen vacancies for the activation of O2. The theoretical calculation reveals that the release of lattice oxygen becomes easy because of a low formation energy of oxygen vacancy, while the high reduction potential is beneficial for the activation of O2 on Ce3+-Ov (oxygen vacancies). Due to above Ce-Mn synergy, the CeMnOx-ES shows more active oxygen species and higher oxygen storage capacity than CeO2-ES and MnOx-ES. The theoretical calculation and experimental results suggest that the adsorbed O2 is more active than lattice oxygen and the catalytic oxidation mainly follows the Langmuir-Hinshelwood mechanism. This study indicates that electrospinning is a novel method to obtain efficient Ce-Mn oxide.
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Affiliation(s)
- Liao Yuxi
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China
| | - Liu Peng
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China; Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, South China University of Technology, Guangzhou, 510006, PR China.
| | - Zhang Jun
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China
| | - Wang Can
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China
| | - Chen Longwen
- College of Light Chemical Industry and Materials Engineering, Shunde Polytechnic, Foshan, 528333, PR China
| | - Yan Dengfeng
- Guangdong Province Hospital for Occupational Disease Prevention and Treatment, Guangzhou, 510399, PR China
| | - Ren Quanming
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China; Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, South China University of Technology, Guangzhou, 510006, PR China
| | - Liang Xiaoliang
- CAS Key Laboratory of Mineralogy and Metallogeny, Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, PR China
| | - Fu Mingli
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China; Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, South China University of Technology, Guangzhou, 510006, PR China
| | - Steven L Suib
- Department of Chemistry, University of Connecticut, Storrs, Connecticut, 06269, USA
| | - Ye Daiqi
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China; Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, South China University of Technology, Guangzhou, 510006, PR China.
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Jiang G, Liu Y, Liu X, Shen Y, Zhang A, Li Z. Enhanced efficiency and mechanism of low-temperature biochar on simultaneous removal of nitrogen and phosphorus by combined heterotrophic nitrification-aerobic denitrification bacteria. Bioresour Technol 2023; 373:128720. [PMID: 36774989 DOI: 10.1016/j.biortech.2023.128720] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 02/04/2023] [Accepted: 02/07/2023] [Indexed: 06/18/2023]
Abstract
In this study, three strains of heterotrophic nitrification-aerobic denitrification (HN-AD) capable of simultaneously removing phosphorus were isolated from activated sludge, and low-temperature coconut shell biochar was prepared. The metabolic effects of combined HN-AD bacteria on the total nitrogen (TN) and total phosphorus (TP) were investigated, and the enhanced efficiency and mechanism of low-temperature biochar on the combined bacteria were also explored. The results indicated that the combined bacteria could adapt to environmental impacts and multiple nitrogen sources. The low-temperature biochar containing more aliphatic carbon and oxygen-containing functional groups enhanced the metabolic activity of combined HN-AD bacteria and accelerated the electron transfer process during nitrogen and phosphorus degradation. The removal efficiencies of TN and TP increased by 68% and 88%, respectively, in the treatment of actual sewage by biochar attached with combined bacteria. The findings form a basis for the engineering utilization of HN-AD and are of great practical significance.
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Affiliation(s)
- Ge Jiang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Yan Ta Road. No.13, Xi'an 710055, China
| | - Yongjun Liu
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Yan Ta Road. No.13, Xi'an 710055, China.
| | - Xingshe Liu
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Yan Ta Road. No.13, Xi'an 710055, China
| | - Yuan Shen
- Yishuiyuan Biotechnology (Xi'an) Co., Ltd., Xi'an 710018, China
| | - Aining Zhang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Yan Ta Road. No.13, Xi'an 710055, China
| | - Zhihua Li
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Yan Ta Road. No.13, Xi'an 710055, China
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Li T, Yang J, Zhou Y, Luo Y, Zhou B, Fang D, Li J, Zhou L. Enhancing sludge dewatering efficiency through bioleaching facilitated by increasing reactive oxygen species. Water Res 2023; 231:119622. [PMID: 36680824 DOI: 10.1016/j.watres.2023.119622] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 01/09/2023] [Accepted: 01/15/2023] [Indexed: 06/17/2023]
Abstract
Bioleaching facilitated by iron-oxidizing bacteria is regarded as a promising sludge dewatering method due to excellent dewaterability and low cost. However, a two-days bioleaching time for sludge conditioning decreased its daily treatment capacity. In fact, Fe2+ easily reacts with O2 to produce reactive oxygen species (ROS) with high oxidizing activity. Can bioleaching performed in Fe2+-rich system generate ROS to decompose sludge extracellular polymeric substances (EPS)? Here both contribution of ROS produced in bioleaching to improve sludge dewaterability and the increase of ROS content to shorten sludge bioleaching treatment time were investigated. The introduction of H2O2 in sludge bioleaching treatment (BS+H2O2) to increase ROS could simultaneously improve sludge dewaterability and decrease bioleaching time. Specific resistance to filtration (SRF) and capillary suction time (CST) reduction ratios (90.3% and 80.9%) in BS+H2O2 process were much higher than those in other processes after only 30 min reaction. Mechanisms of improving sludge dewaterability in BS+H2O2 mainly included ROS oxidation and Fe3+ flocculation by analysis of the contribution factors. These findings not only provide an effectively method to promote sludge dewatering efficiency of bioleaching, but also give new sights into the design of cost-efficient processes for improving the sludge dewatering.
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Affiliation(s)
- Ting Li
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Jiawei Yang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Yujun Zhou
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Yixin Luo
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Bo Zhou
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Di Fang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Jiansheng Li
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Lixiang Zhou
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China.
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Ni T, Zhang H, Yang Z, Zhou L, Pan L, Li C, Yang Z, Liu D. Enhanced adsorption and catalytic degradation of antibiotics by porous 0D/3D Co 3O 4/g-C 3N 4 activated peroxymonosulfate: An experimental and mechanistic study. J Colloid Interface Sci 2022; 625:466-478. [PMID: 35738044 DOI: 10.1016/j.jcis.2022.06.057] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 06/04/2022] [Accepted: 06/12/2022] [Indexed: 01/19/2023]
Abstract
In this work, Co3O4/g-C3N4 catalyst with highly efficient adsorption and degradation of antibiotics was developed based on the combination of three-dimensional (3D) porous morphological controls of g-C3N4 and the loading of Co3O4 quantum dots (Co3O4 QDs). It was discovered that the catalyst can effectively activate peroxymonosulfate (PMS) through a non-photochemical path, and a high tetracycline elimination rate of 99.7% can be achieved within 18 min. The characterization and density functional theory calculation results demonstrated that the porous 3D structure can not only promote the substrate adsorption reaction but also provide large surface area and countless exposed active sites for catalytic reaction. The introduction of Co3O4 QDs lowered activation energy barrier and lead to high energy of PMS adsorption. More efficient charge migration between the catalyst and PMS further accelerated PMS activation. Thus, leading to the excellent catalytic performance. In addition, non-free radical mediated degradation mechanism of catalytic activity was also proposed. This work provides a scheme for designing novel and efficient PMS activators for the removal of abusive antibiotics from aqueous environments.
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Affiliation(s)
- Tianjun Ni
- School of Basic Medical Science, Xinxiang Medical University, Xinxiang 453003, China
| | - Hui Zhang
- School of Basic Medical Science, Xinxiang Medical University, Xinxiang 453003, China
| | - Zhibin Yang
- School of Basic Medical Science, Xinxiang Medical University, Xinxiang 453003, China
| | - Liping Zhou
- School of Basic Medical Science, Xinxiang Medical University, Xinxiang 453003, China
| | - Likun Pan
- Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China.
| | - Chunling Li
- School of Public Health, Xinxiang Medical University, Xinxiang 453003, China
| | - Zhijun Yang
- School of Basic Medical Science, Xinxiang Medical University, Xinxiang 453003, China.
| | - Dong Liu
- School of Public Health, Xinxiang Medical University, Xinxiang 453003, China.
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Liu X, Lu S, Liu Y, Wang Y, Guo X, Chen Y, Zhang J, Wu F. Performance and mechanism of sulfamethoxazole removal in different bioelectrochemical technology-integrated constructed wetlands. Water Res 2021; 207:117814. [PMID: 34741898 DOI: 10.1016/j.watres.2021.117814] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 10/01/2021] [Accepted: 10/24/2021] [Indexed: 06/13/2023]
Abstract
Sulfamethoxazole (SMX) has a high concentration and detection frequency in aquatic environments due to the poor removal efficiency of traditional biological treatment processes. Bioelectrochemical technology-integrated constructed wetlands (CWs) have great potential for SMX removal; however, the process of SMX removal in different bioelectrochemical technology-integrated CWs (microbial fuel cell (MFC) and direct current (EC)) remains unclear. To address this, we examined the mechanism of SMX removal in MFCCW and ECCW. The results revealed that the SMX removal efficiency can reach 96.0 ± 2.4% in the ECCW and 97.2 ± 2.2% in the MFCCW. The enhancement of MFC for SMX removal in CW was slightly better than that in direct current (p > 0.05). It was found that the adsorption process of SMX in the substrate promoted by EC was more enhanced than that by MFC. Furthermore, bioelectrochemical technology improved plant activity, including root and enzymatic (superoxide dismutase, peroxidase, and catalase) activities, and fluorescence parameters (photochemical quenching coefficient, non-photochemical quenching coefficient, and quantum efficiency of PS II). Significant differences were found between CW and ECCW (p < 0.05), while no significant differences were found between CW and MFCCW (p > 0.05). The microbial activity and abundance in CW were improved by bioelectrochemical technology, and the microbial community structure was optimised to be simpler and more stable. However, EC tended to promote microbial and plant activity in CW, whereas MFC tended to optimise the microbial community and improve the tightness and stability of the module. The enhanced difference might also account for the changes in the SMX degradation pathway. 4-aminobenzenesulfonic acid (TP174), 3-amino-5-methylisoxazole (TP99) and 5-methylisoxazole (TP84) were all common products in the three reactors, whereas TP99 underwent further ring-opening in MFCCW and TP174 underwent further hydrolysis in ECCW. This study provided an important reference for the targeted regulation of plants and microorganisms in constructed wetlands via different bioelectrochemistry to enhance characteristic pollutants degradation.
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Affiliation(s)
- Xiaohui Liu
- State Key Laboratory of Environmental Criteria and Risk Assessment, National Engineering Laboratory for Lake Pollution Control and Ecological Restoration, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; School of Environment, Tsinghua University, Beijing 100084, China
| | - Shaoyong Lu
- State Key Laboratory of Environmental Criteria and Risk Assessment, National Engineering Laboratory for Lake Pollution Control and Ecological Restoration, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
| | - Ying Liu
- School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Yongqiang Wang
- State Key Laboratory of Environmental Criteria and Risk Assessment, National Engineering Laboratory for Lake Pollution Control and Ecological Restoration, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Xiaochun Guo
- State Key Laboratory of Environmental Criteria and Risk Assessment, National Engineering Laboratory for Lake Pollution Control and Ecological Restoration, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Yi Chen
- College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Jian Zhang
- School of Environmental Science and Engineering, Shandong University, Qingdao 250100, China
| | - Fengchang Wu
- State Key Laboratory of Environmental Criteria and Risk Assessment, National Engineering Laboratory for Lake Pollution Control and Ecological Restoration, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
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Li T, Duan Z, Qin R, Xu X, Li B, Liu Y, Jiang M, Zhan F, He Y. Enhanced characteristics and mechanism of Cu(II) removal from aqueous solutions in electrocatalytic internal micro-electrolysis fluidized-bed. Chemosphere 2020; 250:126225. [PMID: 32114338 DOI: 10.1016/j.chemosphere.2020.126225] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 02/13/2020] [Accepted: 02/13/2020] [Indexed: 06/10/2023]
Abstract
For the purification of heavy metal wastewater, internal micro-electrolysis (IME) was considered as an effective method but some disadvantage greatly restricts its application. Electrocatalytic internal micro-electrolysis (ECIME) fluidized bed using iron-carbon particles was proposed to avoid disadvantaging of IME. The principal aim of this study was to investigate the enhanced removal characteristics, mechanism, and kinetic behavior of Cu(II) that none clear before. ECIME reactor shows a better copper removal performance and depends much on the polarization of the external electric field (EEF). Both the reaction rate and removal efficiency of copper electrodeposition improved obviously. Noteworthy is more than 88.0% of Cu(II) in aqueous solutions was removed by enhanced electrodeposition, and only about 10.0% of Cu(II) was absorbed and flocculated through the in situ formed iron hydroxyl compounds. Through scanning electron microscopy (SEM) and electrochemical analysis, copper can effectively electrodeposition on the surface of iron-carbon particles in ECIME reactor and accordingly the enhanced mechanisms were proposed. 1) Iron-carbon particles of ECIME formation of microelectrodes with high surface potential, larger specific area, and active sites through electrode collision and repolarization. 2) Copper electrodeposition on the formed microelectrodes exhibited greater reduction peak potential, reaction overpotential and exchange current density, which influenced by the polarization voltage significantly. 3) The electrocatalytic environment tend to in situ generate iron polymer hydroxyl compounds help to further remove residual Cu(II). ECIME fluidized-bed has promised potential for heavy metal containing wastewater purification and metal recovery. In addition, the proposed reaction models will be useful for field application.
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Affiliation(s)
- Tianguo Li
- College of Resources and Environment, Yunnan Agricultural University, Kunming, 650201, PR China; Faculty of Environmental Science and Technology, Kunming University of Science and Technology, Kunming, 650500, PR China
| | - Zhengyang Duan
- Department of Geography and Tourism Management, Chuxiong Normal University, Chuxiong, 675000, PR China
| | - Ronggao Qin
- Faculty of Land Resource Engineering, Kunming University of Science and Technology, Kunming, 650093, PR China.
| | - Xiaojun Xu
- Faculty of Environmental Science and Technology, Kunming University of Science and Technology, Kunming, 650500, PR China
| | - Bo Li
- College of Resources and Environment, Yunnan Agricultural University, Kunming, 650201, PR China
| | - Yue Liu
- College of Resources and Environment, Yunnan Agricultural University, Kunming, 650201, PR China
| | - Ming Jiang
- College of Resources and Environment, Yunnan Agricultural University, Kunming, 650201, PR China.
| | - Fangdong Zhan
- College of Resources and Environment, Yunnan Agricultural University, Kunming, 650201, PR China
| | - Yongmei He
- College of Resources and Environment, Yunnan Agricultural University, Kunming, 650201, PR China
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Zhong D, Li J, Ma W, Qian F. Clarifying the synergetic effect of magnetite nanoparticles in the methane production process. Environ Sci Pollut Res Int 2020; 27:17054-17062. [PMID: 32146670 DOI: 10.1007/s11356-020-07828-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Accepted: 01/22/2020] [Indexed: 06/10/2023]
Abstract
Magnetite nanoparticles (Fe3O4 NPs) were applied in an anaerobic semi-continuous tank reactor (ASTR) to investigate its effect on the anaerobic digestion (AD) of acetate synthetic wastewater. The Fe3O4 NPs corrosion could create a more favorable micro-environment to enhance the methanogens activity. The chemical oxygen demand (COD) removal efficiency and methane production in test (ASTRT) were 31.1% and 101.5% higher than those in control (ASTRC). With the addition of Fe3O4 NPs, the concentration of key coenzyme (F420 and M) increased from averagely 0.523 and 5.352 μmol/g-VSS to 0.956 and 9.267 μmol/g-VSS, and the content of soluble microbial products (SMPs) significantly increased. Additionally, the high-throughput 16S rRNA gene sequencing further confirmed that the percentage of hydrogen-utilizing methanogens (Methanolinea) was up to 62.6% of total archaeal sequences. Fe3O4 NPs addition would accelerate electrons transfer from acids oxidizers to syntrophic methanogenesis, further stimulate acids oxidizers to decompose acetate to H2/CO2, and finally facilitate more methane production.
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Affiliation(s)
- Dan Zhong
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin, 150090, China
| | - Jinxin Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin, 150090, China
| | - Wencheng Ma
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin, 150090, China.
| | - Fengyue Qian
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin, 150090, China
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Song L, Zhang S, Zhang S. Super-high photocatalytic activity, stability and improved photocatalytic mechanism of monodisperse AgBr doped with In. J Hazard Mater 2015; 299:570-576. [PMID: 26259096 DOI: 10.1016/j.jhazmat.2015.07.064] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Revised: 07/22/2015] [Accepted: 07/24/2015] [Indexed: 06/04/2023]
Abstract
Monodisperse In(3+) doped AgBr (In-AgBr) nanoparticles were synthesized by a hydrothermal route. The pure AgBr and In-AgBr samples were investigated by X-ray powder diffraction, transmission electron microscopy, ultraviolet-visible absorption spectroscopy, X-ray photoelectron spectroscopy, measurement of total organic carbon, and electron paramagnetic resonance spectrometry. In-AgBr was more photocatalytically active than pure AgBr in photodegradation of 20 mg/L methyl orange under visible light irradiation (λ>420 nm). The 0.05 mol/L In-AgBr sample showed the highest photodegradation efficiency and high stability. The doped In(3+) expanded the light absorption range, reduced the band gap of AgBr and improved the utilization of photons. The additional In(3+) can inhibit the formation of Ag particles on the surface of AgBr, which can further stabilize AgBr. The doped In(3+) in AgBr served as a temporary site for trapping of photoinduced electrons, and thereby obviously restrained the recombination of photoinduced electron-hole pairs on the surface of AgBr. The enhanced photocatalytic ability of In-AgBr may be mainly attributed to the improved separation efficiency of photogenerated charges.
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Affiliation(s)
- Limin Song
- College of Environment and Chemical Engineering & State Key Laboratory of Hollow-Fiber Membrane Materials and Membrane Processes, Tianjin Polytechnic University, Tianjin 300387, PR China.
| | - Shujuan Zhang
- College of Science, Tianjin University of Science & Technology, Tianjin 300457, PR China.
| | - Shuna Zhang
- College of Textile Engineering, Zhejiang Industry Polytechnic College, Shaoxing 312000, PR China
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10
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Zhang S, Zhang S, Song L. Co(II)-grafted Ag3PO4 photocatalysts with unexpected photocatalytic ability: Enhanced photogenerated charge separation efficiency, photocatalytic mechanism and activity. J Hazard Mater 2015; 293:72-80. [PMID: 25827270 DOI: 10.1016/j.jhazmat.2015.03.047] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 03/20/2015] [Accepted: 03/22/2015] [Indexed: 06/04/2023]
Abstract
Since the photocatalytic capability is determined by the separation and transmission efficiency of photoinduced charges, its improvement remains a challenge for development of efficient photocatalysts. Here, we made large improvement on the surface of Ag3PO4 using Co(II)-grafted Ag3PO4 by a hydrothermal method. During the photocatalytic process, Co(II) was oxidized to Co(III) by the photogenerated holes under visible light radiation, which enhanced the separation efficiency of photogenerated charges. Meanwhile, the Co(III) as-formed could oxidize dye molecules, which recovered the Co(II). The synergy of Co(II) and Ag3PO4 greatly promoted the separation and transmission efficiency of the photogenerated charges, and severely improved the photocatalytic activity of Ag3PO4. The surface grafted Co(II) on Ag3PO4 is responsible for the enhancement of photocatalytic activity.
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Affiliation(s)
- Shuna Zhang
- College of Textile Engineering, Zhejiang Industry Polytechnic College, Shaoxing 312000, PR China
| | - Shujuan Zhang
- College of Science, Tianjin University of Science & Technology, Tianjin 300457, PR China.
| | - Limin Song
- College of Environment and Chemical Engineering & State Key Laboratory of Hollow-Fiber Membrane Materials and Membrane Processes, Tianjin Polytechnic University, Tianjin 300387, PR China.
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Chen Y, Li H, Liu W, Tu Y, Zhang Y, Han W, Wang L. Electrochemical degradation of nitrobenzene by anodic oxidation on the constructed TiO2-NTs/SnO2-Sb/PbO2 electrode. Chemosphere 2014; 113:48-55. [PMID: 25065789 DOI: 10.1016/j.chemosphere.2014.03.122] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 03/21/2014] [Accepted: 03/25/2014] [Indexed: 06/03/2023]
Abstract
The interlayer of Sb-doped SnO2 (SnO2-Sb) and TiO2 nanotubes (TiO2-NTs) on Ti has been introduced into the PbO2 electrode system with the aim to reveal the mechanism of enhanced electrochemical performance of TiO2-NTs/SnO2-Sb/PbO2 electrode. In contrast with the traditional Ti/SnO2-Sb/PbO2 electrode, the constructed PbO2 electrode has a more regular and compact morphology with better oriented crystals of lower size. The TiO2-NTs/SnO2-Sb interlayer prepared by electrodeposition process improves PbO2 coating structure effectively, and enhances the electrochemical performance of PbO2 electrode. Kinetic analyses indicated that the electrochemical oxidation of nitrobenzene on the PbO2 electrodes followed pseudo-first-order reaction, and mass transport was enhanced at the constructed electrode. The accumulation of nitrocompounds of degradation intermediates on constructed electrode was lower, and almost all of the nitro groups were eliminated from aromatic rings after 6h of electrolysis. Higher combustion efficiency was obtained on the constructed TiO2-NTs/SnO2-Sb/PbO2 electrode. The intermediates of nitrobenzene oxidation were confirmed by IC and GC/MS.
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Affiliation(s)
- Yong Chen
- Jiangsu Key Laboratory of Environmental Engineering, Jiangsu Provincial Academy of Environmental Science, Nanjing 210036, China; School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu Province, China.
| | - Hongyi Li
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu Province, China; Department of Environmental Engineering, Nanjing Institute of Technology, Nanjing 211167, Jiangsu Province, China
| | - Weijing Liu
- Jiangsu Key Laboratory of Environmental Engineering, Jiangsu Provincial Academy of Environmental Science, Nanjing 210036, China
| | - Yong Tu
- Jiangsu Key Laboratory of Environmental Engineering, Jiangsu Provincial Academy of Environmental Science, Nanjing 210036, China
| | - Yaohui Zhang
- Jiangsu Key Laboratory of Environmental Engineering, Jiangsu Provincial Academy of Environmental Science, Nanjing 210036, China
| | - Weiqing Han
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu Province, China
| | - Lianjun Wang
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu Province, China.
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