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Manzar MS, Palaniandy P, Georgin J, Franco DSP, Zubair M, Muazu ND, Faisal W, El Messaoudi N. Synthesis of LDH-MgAl and LDH-MgFe composites for the efficient removal of the antibiotic from water. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024:10.1007/s11356-024-34837-y. [PMID: 39240434 DOI: 10.1007/s11356-024-34837-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2024] [Accepted: 08/24/2024] [Indexed: 09/07/2024]
Abstract
In this study, novel lamellar double hydroxide composites (LDH-MgAl and LDH-MgFe) were synthesized at different metal salt ratios (1:1 to 3:1) and fully characterized using various techniques such as XRD, FTIR, SEM, EDS, and TGA. The resulting LDHs demonstrated a high affinity for efficiently removing tetracycline (TC) antibiotic from water, particularly at a moderate molar ratio of 3:1. This ratio exhibited improved structural characteristics, resulting in better TC uptake from water. The improved performance was supported by the increased abundance of surface functional groups (OH, NO3, CO32-, C-O-C, Fe-O, and Al-O-Al). The TGA analysis established the high stability of the LDHs when subjected to high temperatures. The kinetics of TC adsorption onto LDH fitted with the PSO (R2 = 0.935-0.994) and Avrami (R2 = 0.9528-0.9824) models, while the equilibrium data fitted the Liu and Langmuir isotherm models, with maximum monolayer adsorption capacities of 101.1 mg g-1 and 70.83 mg g-1, respectively-significantly higher than many reported values in the literature. The positive values of ΔH0 and ΔS0 indicate an endothermic process, with TC removal mechanisms influenced by physical interactions, such as hydrogen bonding, electrostatic interaction, and π-cation with the surface functional groups of the LDH adsorbents. These results suggest that LDH-MgAl and LDH-MgFe are promising adsorbents for the removal of TC from water.
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Affiliation(s)
- Mohammad Saood Manzar
- Department of Environmental Engineering, College of Engineering, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | | | - Jordana Georgin
- Department of Civil and Environmental, Universidad de La Costa, CUC, Calle 58 # 55-66, Barranquilla, Atlántico, Colombia
| | - Dison Stracke Pfingsten Franco
- Department of Civil and Environmental, Universidad de La Costa, CUC, Calle 58 # 55-66, Barranquilla, Atlántico, Colombia
| | - Mukarram Zubair
- Department of Environmental Engineering, College of Engineering, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Nuhu Dalhat Muazu
- Department of Environmental Engineering, College of Engineering, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Wamda Faisal
- Department of Environmental Engineering, College of Engineering, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Noureddine El Messaoudi
- Laboratory of Applied Chemistry and Environment, Faculty of Sciences, Ibn Zohr, University, 80000, Agadir, Morocco.
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salamaat H, Ghafuri H, Ghanbari N. Design and synthesis of LDH nano composite functionalized with trimesic acid and its environmental application in adsorbing organic dyes indigo carmine and methylene blue. Heliyon 2024; 10:e33656. [PMID: 39100470 PMCID: PMC11295991 DOI: 10.1016/j.heliyon.2024.e33656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 06/24/2024] [Accepted: 06/25/2024] [Indexed: 08/06/2024] Open
Abstract
This work designed and prepared an organic-inorganic nanocomposite using layered double hydroxide (LDH) inorganic substrate and trimesic acid (TMA) as chelating agent. Subsequently, the synthesized organic-inorganic nanocomposite was assessed using multiple identification methods, including FTIR, EDX, XRD, TGA, and FESEM, and the outcomes demonstrated that the intended structure was successfully prepared. Also, in order to investigate the efficiency of the Mg-Al LDH-TMA nanocomposite as an efficient nano adsorbent, it was used for removal of indigo carmine (IC) and methylene blue (MB) from aqueous solutions. This synthetic nanocomposite showed a high adsorption capacity. The efficiency of the produced nanocomposite in the adsorption of selected dyes was investigated with the help of batch adsorption studies performed in a variety of experimental settings, including dye concentration, adsorbent dose, pH, adsorption temperature and contact time. Furthermore, the produced Mg-Al LDH-TMA nanocomposite exhibits strong stability and can be recycled and reused five times in a row, which is well consistent with the principles of green chemistry.
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Affiliation(s)
- Hoda salamaat
- Catalysts and Organic Synthesis Research Laboratory, Department of Chemistry, Iran University of Science and Technology, Tehran, 16846-13114, Iran
| | - Hossein Ghafuri
- Catalysts and Organic Synthesis Research Laboratory, Department of Chemistry, Iran University of Science and Technology, Tehran, 16846-13114, Iran
| | - Nastaran Ghanbari
- Catalysts and Organic Synthesis Research Laboratory, Department of Chemistry, Iran University of Science and Technology, Tehran, 16846-13114, Iran
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3
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Ara M, Ghafuri H. Design and preparation of a novel Mg-Al LDH@EDTA-Melamine nanocomposite for effective adsorptive removal of methylene blue and rhodamine B dyes from water. Heliyon 2024; 10:e32447. [PMID: 38994068 PMCID: PMC11237852 DOI: 10.1016/j.heliyon.2024.e32447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 05/31/2024] [Accepted: 06/04/2024] [Indexed: 07/13/2024] Open
Abstract
This paper deals with the preparation of a novel nanocomposite consisted of magnesium-aluminum layered double hydroxide (Mg-Al LDH) and ethylenediaminetetraacetic acid (EDTA) as well as melamine (MA) as an adsorbent. This nanocomposite was utilized to adsorb different dyes such as rhodamine B (RhB) and methylene blue (MB) from water. The prepared adsorbent was characterized using FT-IR, EDS, XRD, TGA, and FE-SEM analyses. The effects of various parameters such as concentration, time, adsorbent dosage, temperature, and pH were tested to investigate their influence on adsorption conditions. Both methylene blue and rhodamine B dyes showed pseudo-second-order adsorption kinetics, and their adsorption followed the Langmuir isotherm. Moreover, the maximum adsorption capacities for methylene blue and rhodamine B were found to be 1111.103 mg/g at 45 °C and 232.558 mg/g at 60 °C, respectively. Additionally, the adsorption processes were found to be spontaneous (ΔG°< 0, for both dyes) and exothermic (ΔH° = -12.42 kJ/mol for methylene blue and ΔH° = -25.84 kJ/mol for rhodamine B) for both dyes. Hydrogen bonding and electrostatic forces are responsible for the interactions occur between the nanocomposite and the functional groups in the dyes. The experimental findings demonstrated a greater adsorption rate of MB than RhB, suggesting the adsorbent's stronger affinity for MB. This preference is likely due to MB's size, specific functional groups, and smaller molecule size, enabling stronger interactions and more efficient access to adsorption sites compared to RhB. Even after recycling 4 times, the dye adsorption percentages of the adsorbent for MB and RhB dyes were 90 % and 87 %, but the desorption percentages of the adsorbate dyes were 85 % and 80 %, respectively. The prepared adsorbent boasts several unique properties, such as the swift and effortless adsorption of MB and RhB dyes, straightforward synthesis, mild adsorption conditions, remarkable efficiency, and the ability to be recycled up to 4 times without a significant decrease in activity.
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Affiliation(s)
- Mohammad Ara
- Catalysts and Organic Synthesis Research Laboratory, Department of Chemistry, Iran University of Science and Technology, Tehran, 16846-13114, Iran
| | - Hossein Ghafuri
- Catalysts and Organic Synthesis Research Laboratory, Department of Chemistry, Iran University of Science and Technology, Tehran, 16846-13114, Iran
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De Geest M, Michielsen B, Ciocarlan RG, Cool P, Seftel EM. Structured LDH/Bentonite Composites for Chromium Removal and Recovery from Aqueous Solutions. Molecules 2023; 28:4879. [PMID: 37375434 DOI: 10.3390/molecules28124879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 06/16/2023] [Accepted: 06/18/2023] [Indexed: 06/29/2023] Open
Abstract
This study focuses on chromium removal through adsorption and ion exchange using structured calcined layered double hydroxide (LDH) (MgAl)-bentonite composites. Firstly, the powders were structured into granulates to study the effect on Cr sorption kinetics to circumvent the limitations of working with powders in real-life applications. Secondly, the regeneration of the structured composites was optimized to enable multi-cycling operation, which is the key for their applicability beyond laboratory scale. Firstly, the LDH/bentonite ratio was optimized to obtain the best performance for the removal of Cr3+ and Cr6+ species. In powder form, the calcined adsorbent containing 80 wt% LDH and 20 wt% bentonite performed best with an adsorption capacity of 48 and 40 mg/g for Cr3+ and Cr6+, respectively. The desorption was optimized by studying the effect of the NaCl concentration and pH, with a 2 M NaCl solution without pH modification being optimal. The kinetic data of the adsorption and desorption steps were modelled, revealing a pseudo-second order model for both. This was also demonstrated using XRD and Raman measurements after the Cr3+ and Cr6+ adsorption tests, indicating successful uptake and revealing the adsorption mechanism. Finally, five consecutive adsorption-desorption cycles were performed, each showing nearly 100% adsorption and desorption.
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Affiliation(s)
- Mitra De Geest
- Laboratory of Adsorption & Catalysis, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Bart Michielsen
- VITO Flemish Institute for Technological Research, Boeretang 200, 2400 Mol, Belgium
| | - Radu-G Ciocarlan
- Laboratory of Adsorption & Catalysis, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Pegie Cool
- Laboratory of Adsorption & Catalysis, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Elena M Seftel
- VITO Flemish Institute for Technological Research, Boeretang 200, 2400 Mol, Belgium
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Effective removal of nanoplastics from water by cellulose/MgAl layered double hydroxides composite beads. Carbohydr Polym 2022; 298:120059. [DOI: 10.1016/j.carbpol.2022.120059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 08/27/2022] [Accepted: 08/28/2022] [Indexed: 11/21/2022]
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Cheng X, Liu W, Zhang C, Chen X, Duan S, Fu H. Synthesis and electrospinning of multiscale‐ordered
PLA
/
LDH
@
AgGB
composite nanofibrous membrane for antibacterial and oil–water separation. J Appl Polym Sci 2022. [DOI: 10.1002/app.52621] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Xiao‐Qiong Cheng
- Guizhou Norm University School of Materials and Architectural Engineering Guiyang People's Republic of China
| | - Wei Liu
- Guizhou Institutes of Technology School of Materials and Energy Engineering Guiyang People's Republic of China
| | - Chun Zhang
- Guizhou Institutes of Technology School of Materials and Energy Engineering Guiyang People's Republic of China
| | - Xiao‐Cheng Chen
- Guizhou Institutes of Technology School of Materials and Energy Engineering Guiyang People's Republic of China
| | - Shu‐Qian Duan
- Guizhou Norm University School of Materials and Architectural Engineering Guiyang People's Republic of China
| | - Hai Fu
- Guizhou Norm University School of Materials and Architectural Engineering Guiyang People's Republic of China
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Removal of Tar Contents Derived from Lignocellulosic Biomass Gasification Facilities Using MgAl-LDH@clinoptilolite. Catalysts 2021. [DOI: 10.3390/catal11091111] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Gasification of lignocellulosic biomass requires the effective removal method of tar. This study focused on the application of specially designed Mg/Al-layered double hydroxides clinoptilolite (Mg/Al-LDH@clinoptilolite) to improve the removal efficiency of tar, which would eventually lead to enhancing the power efficiency of gasification, preventing damage to facilities, and deducing durability improvement plans. Zeolite-layered double hydroxides impregnated with clinoptilolite, a natural zeolite, and Mg/Al-layered double hydroxide incorporated into conventional water scrubbers were prepared to enhance the removal efficiency of the tar and improve the quality of the syngas produced during the gasification process. The simultaneous removal of moisture and CO2 in the syngas was also investigated during the removal of the tar. The drastic decrease in tar and CO2 concentration was confirmed, which triggered a relative increase in the effective content of inflammable gas. The findings of the present study provide a practical approach to increasing power efficiency and durability during the gasification of lignocellulosic biomass.
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Huang S, Ouyang T, Chen J, Wang Z, Liao S, Li X, Liu ZQ. Synthesis of nickel-iron layered double hydroxide via topochemical approach: Enhanced surface charge density for rapid hexavalent chromium removal. J Colloid Interface Sci 2021; 605:602-612. [PMID: 34343733 DOI: 10.1016/j.jcis.2021.07.091] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 07/07/2021] [Accepted: 07/16/2021] [Indexed: 11/17/2022]
Abstract
Hexavalent chromium (Cr(VI)) is considered to be a potential metal contaminant because of its toxicity and carcinogenicity. In this work, the surface charge density of nickel-iron layered double hydroxide (NiFe LDH) is tuned through iron valence change to improve the performance in adsorption of Cr(VI). The addition of iron divalent in the precursor enhances the surface positivity and reducibility of Fe2+-NiFe LDH, resulting in a nearly 150% Cr(VI) maximum adsorption capacity improvement. The increase of hydroxyl groups and charge density on the surface of NiFe LDH is due to the topological chemical transition from Ni2+-Fe2+ LDH to Ni2+-Fe3+ LDH. The adsorption of Cr(VI) onto Fe2+-NiFe LDH prepared via topochemical approach is highly pH-dependent. The adsorption dynamics and isotherms results may be clearly elucidated by the pseudo-second-order model and Langmuir isotherm model. Electrostatic attraction, interlayer anion exchange and adsorption-coupled reduction are proven to be the main Cr(VI) removal mechanisms for Fe2+-NiFe LDH. This finding demonstrates that Fe2+-NiFe LDH adsorbents have potential application for efficient removal of Cr(VI) pollutants.
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Affiliation(s)
- Shuangqiu Huang
- School of Environmental Science and Engineering/Institute of Environmental Research at Greater Bay/Guangzhou Key Laboratory for Clean Energy and Materials/Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Ting Ouyang
- School of Chemistry and Chemical Engineering/Institute of Clean Energy and Materials/Guangzhou Key Laboratory for Clean Energy and Materials/Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou Higher Education Mega Center, No. 230 Wai Huan Xi Road, 510006, China
| | - Jinyan Chen
- School of Environmental Science and Engineering/Institute of Environmental Research at Greater Bay/Guangzhou Key Laboratory for Clean Energy and Materials/Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Zhu Wang
- School of Environmental Science and Engineering/Institute of Environmental Research at Greater Bay/Guangzhou Key Laboratory for Clean Energy and Materials/Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China.
| | - Shuiqiu Liao
- School of Environmental Science and Engineering/Institute of Environmental Research at Greater Bay/Guangzhou Key Laboratory for Clean Energy and Materials/Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Xiuying Li
- School of Environmental Science and Engineering/Institute of Environmental Research at Greater Bay/Guangzhou Key Laboratory for Clean Energy and Materials/Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Zhao-Qing Liu
- School of Chemistry and Chemical Engineering/Institute of Clean Energy and Materials/Guangzhou Key Laboratory for Clean Energy and Materials/Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou Higher Education Mega Center, No. 230 Wai Huan Xi Road, 510006, China.
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9
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Xu S, Zhang L, Zhao J, Cheng J, Yu Q, Zhang S, Zhao J, Qiu X. Remediation of chromium-contaminated soil using delaminated layered double hydroxides with different divalent metals. CHEMOSPHERE 2020; 254:126879. [PMID: 32361545 DOI: 10.1016/j.chemosphere.2020.126879] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Revised: 04/20/2020] [Accepted: 04/22/2020] [Indexed: 06/11/2023]
Abstract
Soil is commonly polluted by chromium, and layered double hydroxides (LDHs) are widely used for chromium removal due to their strong adsorption capacity and the unique properties of their delaminated products. In this study, delaminated LDHs (S-Mg-LDH and S-Ca-LDH) and their original LDHs were used to remediate Cr(VI)-contaminated soil. A series of characterizations confirmed the successful synthesis of delaminated LDHs whose sheet structure was thinner with a greater surface energy than the original LDHs. The remediation results indicated that delaminated LDHs could more efficiently immobilize Cr(VI) in soil. The immobilization rate of S-Mg-LDH was 64.32%, while Mg-LDH was only 8.09%. However, at low dosages, the efficiency of S-Ca-LDH was 28.1% while Ca-LDH was 5.16%, but they had similar effects at high doses. Moreover, soil pH had little effect on their removal efficiencies. The toxicity characteristic leaching procedure (TCLP) results showed that the leaching of Cr(VI) in soil after treatment with S-Mg-LDH, S-Ca-LDH, Mg-LDH, and Ca-LDH was reduced by 75.43%, 72.43%, 86.55%, and 75.90%, respectively. The phytotoxicity tests of soil treated by S-Mg-LDH and S-Ca-LDH revealed that they effectively reduced the toxicity of chromium and lowered its bioaccumulation. Overall, this study confirms the feasibility of delaminated LDHs for Cr(VI) immobilization in soils.
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Affiliation(s)
- Shuang Xu
- School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Luping Zhang
- School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Jiawen Zhao
- School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Jing Cheng
- School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Qianqian Yu
- School of Earth Science, China University of Geosciences, Wuhan, 430074, China
| | - Shuwang Zhang
- School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Jialing Zhao
- School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Xinhong Qiu
- School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan, China; Hubei Environmental Engineering Technology Research Center for Chemical Engineering Pollution Control, Wuhan, China.
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Zhang L, He F, Mao W, Guan Y. Fast and efficient removal of Cr(VI) to ppb level together with Cr(III) sequestration in water using layered double hydroxide interclated with diethyldithiocarbamate. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 727:138701. [PMID: 32334229 DOI: 10.1016/j.scitotenv.2020.138701] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 03/24/2020] [Accepted: 04/13/2020] [Indexed: 06/11/2023]
Abstract
It is still a great challenge to find an eco-friendly, easy-to-synthesize, and cheap adsorbent to rapidly remove Cr(VI) to ppb level in the Cr(VI)-polluted water. Herein, a new layered double hydroxide nanocage intercalated with diethyldithiocarbamate (DDTC-LDH) was fabricated via a facile calcination-rehydration method. The DDTC-LDH rapidly decreased Cr(VI) concentration from 5 to <0.05 mg/L within 35 min, and only a few seconds were required to completely remove it at an initial concentration of 0.5-1 mg/L, primarily attributed to the effective adsorption-reduction of Cr(VI) to Cr(III) by sulfur atoms in CS and CS groups. Attractively, the generated Cr(III) was also quickly removed to below 0.1 mg/L via an opportune Lewis hard-hard interaction with C-SOx groups produced through CS oxidation. Additionally, Cr(VI) could be removed by DDTC-LDH at a wide pH application range (3.17-10.78) and with weak effects by coexisting anions (Cl-, NO3-, CO32-, SO42-, and PO43-). We systematically analyzed and proposed the mechanisms for Cr(VI) removal by the DDTC-LDH, orderly containing electrostatic attraction, Cr(VI) complexation by sulfur atoms in CS and CS groups, reduction of the Cr(VI) to Cr(III) by the CS and CS groups, and Cr(III) complexation by sulfur atoms in C-SOx groups. Our results provide new insights into the Cr(VI) removal using organosulfur compounds, that is to say, the organosulfur group Lewis hardness increased (from C-S to C-SOx) as the Cr species Lewis hardness increased (from Cr(VI) to Cr(III)), so as to opportunely ensure fast and efficient capture of both Cr(VI) and Cr(III) via Lewis acid-base interactions.
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Affiliation(s)
- Lixun Zhang
- Guangdong Provincial Engineering Technology Research Center for Urban Water Cycle and Water Environment Safety, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, PR China; State Environmental Protection Key Laboratory of Microorganism Application and Risk Control, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Fangxin He
- Guangdong Provincial Engineering Technology Research Center for Urban Water Cycle and Water Environment Safety, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, PR China; State Environmental Protection Key Laboratory of Microorganism Application and Risk Control, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Wei Mao
- Guangdong Provincial Engineering Technology Research Center for Urban Water Cycle and Water Environment Safety, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, PR China; State Environmental Protection Key Laboratory of Microorganism Application and Risk Control, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Yuntao Guan
- Guangdong Provincial Engineering Technology Research Center for Urban Water Cycle and Water Environment Safety, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, PR China; State Environmental Protection Key Laboratory of Microorganism Application and Risk Control, School of Environment, Tsinghua University, Beijing 100084, PR China.
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11
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Kinetics of Cross-Linking Reaction of Epoxy Resin with Hydroxyapatite-Functionalized Layered Double Hydroxides. Polymers (Basel) 2020; 12:polym12051157. [PMID: 32443636 PMCID: PMC7284359 DOI: 10.3390/polym12051157] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 05/11/2020] [Accepted: 05/15/2020] [Indexed: 11/16/2022] Open
Abstract
The cure kinetics analysis of thermoset polymer composites gives useful information about their properties. In this work, two types of layered double hydroxide (LDH) consisting of Mg2+ and Zn2+ as divalent metal ions and CO32- as an anion intercalating agent were synthesized and functionalized with hydroxyapatite (HA) to make a potential thermal resistant nanocomposite. The curing potential of the synthesized nanoplatelets in the epoxy resin was then studied, both qualitatively and quantitatively, in terms of the Cure Index as well as using isoconversional methods, working on the basis of nonisothermal differential scanning calorimetry (DSC) data. Fourier transform infrared spectroscopy (FTIR) was used along with X-ray diffraction (XRD) and thermogravimetric analysis (TGA) to characterize the obtained LDH structures. The FTIR band at 3542 cm-1 corresponded to the O-H stretching vibration of the interlayer water molecules, while the weak band observed at 1640 cm-1 was attributed to the bending vibration of the H-O of the interlayer water. The characteristic band of carbonated hydroxyapatite was observed at 1456 cm-1. In the XRD patterns, the well-defined (00l) reflections, i.e., (003), (006), and (110), supported LDH basal reflections. Nanocomposites prepared at 0.1 wt % were examined for curing potential by the Cure Index as a qualitative criterion that elucidated a Poor cure state for epoxy/LDH nanocomposites. Moreover, the curing kinetics parameters including the activation energy (Eα), reaction order, and the frequency factor were computed using the Friedman and Kissinger-Akahira-Sunose (KAS) isoconversional methods. The evolution of Eα confirmed the inhibitory role of the LDH in the crosslinking reactions. The average value of Eα for the neat epoxy was 54.37 kJ/mol based on the KAS method, whereas the average values were 59.94 and 59.05 kJ/mol for the epoxy containing Zn-Al-CO3-HA and Mg Zn-Al-CO3-HA, respectively. Overall, it was concluded that the developed LDH structures hindered the epoxy curing reactions.
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12
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Li S, Mu B, Dong W, Liang O, Shao S, Wang A. Incorporation of Lutein on Layered Double Hydroxide for Improving the Environmental Stability. Molecules 2020; 25:molecules25051231. [PMID: 32182848 PMCID: PMC7179472 DOI: 10.3390/molecules25051231] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 03/06/2020] [Accepted: 03/06/2020] [Indexed: 12/21/2022] Open
Abstract
To overcome the poor stability of natural lutein to environmental factors, layered double hydroxide was incorporated by a green mechanical grinding process. The influences of external factors (chemical reagents, heating and light) on the stability of lutein before and after being loaded were evaluated. The results confirmed that lutein was mainly adsorbed on the surface of layered double hydroxide (LDH) via the chemical interaction. Compared with pure lutein, the thermal decomposition of lutein/LDH was improved from 100 °C to 300 °C, and the retention ratio of lutein was increased by about 8.64% and 21.47% after 96 h of light exposure and accelerated degradation, respectively. It is expected that the stable lutein/LDH composites may constitutean additive in animal feed.
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Affiliation(s)
- Shue Li
- Key Laboratory of Clay Mineral Applied Research of Gansu Province, Center of Eco-Materials and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China; (S.L.); (W.D.); (O.L.); (S.S.)
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
- Center of Xuyi Palygorskite Applied Technology, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Xuyi 211700, China
| | - Bin Mu
- Key Laboratory of Clay Mineral Applied Research of Gansu Province, Center of Eco-Materials and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China; (S.L.); (W.D.); (O.L.); (S.S.)
- Center of Xuyi Palygorskite Applied Technology, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Xuyi 211700, China
- Correspondence: (B.M.); (A.W.); Tel.: +86-931-4868118 (A.W.); Fax: +86-931-4968019 (A.W.)
| | - Wenkai Dong
- Key Laboratory of Clay Mineral Applied Research of Gansu Province, Center of Eco-Materials and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China; (S.L.); (W.D.); (O.L.); (S.S.)
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
- Center of Xuyi Palygorskite Applied Technology, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Xuyi 211700, China
| | - Oing Liang
- Key Laboratory of Clay Mineral Applied Research of Gansu Province, Center of Eco-Materials and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China; (S.L.); (W.D.); (O.L.); (S.S.)
- Center of Xuyi Palygorskite Applied Technology, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Xuyi 211700, China
| | - Shijun Shao
- Key Laboratory of Clay Mineral Applied Research of Gansu Province, Center of Eco-Materials and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China; (S.L.); (W.D.); (O.L.); (S.S.)
- Center of Xuyi Palygorskite Applied Technology, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Xuyi 211700, China
| | - Aiqin Wang
- Key Laboratory of Clay Mineral Applied Research of Gansu Province, Center of Eco-Materials and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China; (S.L.); (W.D.); (O.L.); (S.S.)
- Center of Xuyi Palygorskite Applied Technology, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Xuyi 211700, China
- Correspondence: (B.M.); (A.W.); Tel.: +86-931-4868118 (A.W.); Fax: +86-931-4968019 (A.W.)
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13
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Soltani R, Marjani A, Shirazian S. A hierarchical LDH/MOF nanocomposite: single, simultaneous and consecutive adsorption of a reactive dye and Cr(vi). Dalton Trans 2020; 49:5323-5335. [PMID: 32248208 DOI: 10.1039/d0dt00680g] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The design and development of an environmentally benign porous adsorbent for effective simultaneous adsorption of organic dyes and heavy metals from water are important but remain a big challenge. Herein, we have designed a layered double hydroxide/metal-organic framework-based hierarchical nanocomposite (LDH/MOF HNC) by a facile, room-temperature in situ approach. This paper for the first time reports a hierarchical trimodal micro-meso-macroporous LDH/MOF composite with a high surface area (surface area 1282 m2 g-1 and pore volume 0.93 cm3 g-1), synthesised by uniformly growing MOF nanocrystals on the surface of LDH nanosheet ultrathin films. An attempt is made to quantitatively demonstrate the adsorption data via suitable nonlinear kinetic and isotherm equations for single, simultaneous, and consecutive adsorption of the orange II reactive dye and Cr(vi). Experiments were performed at various values of pH (6.0-11.0), adsorbent dosages (1.0-8.0 mg), adsorbate concentrations (5-500 mg L-1), and temperatures (293-323 K). The Langmuir model revealed a satisfactory fit to the equilibrium data of the LDH/MOF HNC (correlation coefficients R2 > 0.98) with a calculated maximum adsorption capacity of 1173 and 733 mg g-1 for orange II and Cr(vi), respectively, in a simultaneous adsorption system. The results of the study demonstrated that LDH/MOF HNCs could potentially be applied as a promising nanoadsorbent for the simultaneous removal and extraction of toxic dyes and metals from water.
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Affiliation(s)
- Roozbeh Soltani
- Department of Chemistry, Arak Branch, Islamic Azad University, Arak, Iran
| | - Azam Marjani
- Department of Chemistry, Arak Branch, Islamic Azad University, Arak, Iran
| | - Saeed Shirazian
- Department for Management of Science and Technology Development, Ton Duc Thang University, Ho Chi Minh City, Vietnam. and Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City, Vietnam
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14
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Smalenskaite A, Kaba MM, Grigoraviciute-Puroniene I, Mikoliunaite L, Zarkov A, Ramanauskas R, Morkan IA, Kareiva A. Sol-Gel Synthesis and Characterization of Coatings of Mg-Al Layered Double Hydroxides. MATERIALS (BASEL, SWITZERLAND) 2019; 12:E3738. [PMID: 31766177 PMCID: PMC6888420 DOI: 10.3390/ma12223738] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 11/11/2019] [Accepted: 11/11/2019] [Indexed: 02/06/2023]
Abstract
In this study, new synthetic approaches for the preparation of thin films of Mg-Al layered double hydroxides (LDHs) have been developed. The LDHs were fabricated by reconstruction of mixed-metal oxides (MMOs) in deionized water. The MMOs were obtained by calcination of the precursor gels. Thin films of sol-gel-derived Mg-Al LDHs were deposited on silicon and stainless-steel substrates using the dip-coating technique by a single dipping process, and the deposited film was dried before the new layer was added. Each layer in the preparation of the Mg-Al LDH multilayers was separately annealed at 70 °C or 300 °C in air. Fabricated Mg-Al LDH coatings were characterized by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), and atomic force microscopy (AFM). It was discovered that the diffraction lines of Mg3Al LDH thin films are sharper and more intensive in the sample obtained on the silicon substrate, confirming a higher crystallinity of synthesized Mg3Al LDH. However, in both cases the single-phase crystalline Mg-Al LDHs have formed. To enhance the sol-gel processing, the viscosity of the precursor gel was increased by adding polyvinyl alcohol (PVA) solution. The LDH coatings could be used to protect different substrates from corrosion, as catalyst supports, and as drug-delivery systems in medicine.
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Affiliation(s)
- A. Smalenskaite
- Department of Inorganic Chemistry, Faculty of Chemistry, Vilnius University, Vilnius LT-03225, Lithuania; (A.S.); (I.G.-P.); (L.M.); (A.Z.)
| | - M. M. Kaba
- Department of Chemistry, Institute of Natural Sciences, Bolu Abant Izzet Baysal University, 14030 Bolu, Turkey; (M.M.K.); (I.A.M.)
| | - I. Grigoraviciute-Puroniene
- Department of Inorganic Chemistry, Faculty of Chemistry, Vilnius University, Vilnius LT-03225, Lithuania; (A.S.); (I.G.-P.); (L.M.); (A.Z.)
| | - L. Mikoliunaite
- Department of Inorganic Chemistry, Faculty of Chemistry, Vilnius University, Vilnius LT-03225, Lithuania; (A.S.); (I.G.-P.); (L.M.); (A.Z.)
- Center for Physical Sciences and Technology, LT-10257 Vilnius, Lithuania;
| | - A. Zarkov
- Department of Inorganic Chemistry, Faculty of Chemistry, Vilnius University, Vilnius LT-03225, Lithuania; (A.S.); (I.G.-P.); (L.M.); (A.Z.)
| | - R. Ramanauskas
- Center for Physical Sciences and Technology, LT-10257 Vilnius, Lithuania;
| | - I. A. Morkan
- Department of Chemistry, Institute of Natural Sciences, Bolu Abant Izzet Baysal University, 14030 Bolu, Turkey; (M.M.K.); (I.A.M.)
| | - A. Kareiva
- Department of Inorganic Chemistry, Faculty of Chemistry, Vilnius University, Vilnius LT-03225, Lithuania; (A.S.); (I.G.-P.); (L.M.); (A.Z.)
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15
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Xiang C, Wang H, Ji Q, Zhang G, Qu J. Tracking Internal Electron Shuttle Using X-ray Spectroscopies in La/Zr Hydroxide for Reconciliation of Charge-Transfer Interaction and Coordination toward Phosphate. ACS APPLIED MATERIALS & INTERFACES 2019; 11:24699-24706. [PMID: 31246397 DOI: 10.1021/acsami.9b05397] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Metallic hydroxides have been applied as the adsorbents of oxyanion contaminants, with the oxygen-bonded metal (M-O) considered as the core site for adsorption. For enhanced adsorption toward oxyanions, multimetallic modification of M-O is a promising approach for high removal performance. Here, bimetallic La/Zr hydroxides were prepared via a solvothermal route with varying La/Zr dosages. Bimetallic La/Zr hydroxides exhibited higher oxyanion adsorption capacity than La or Zr hydroxide. A maximum phosphate adsorption capacity of ∼160 mg g-1 was achieved under the La/Zr atomic ratio of 1:1, representing a new record among comparable adsorbents. X-ray photoelectron spectroscopy and X-ray absorption near-edge structure (XANES) spectroscopy showed that the incorporation of [LaO6] and [ZrO6] can induce an internal charge shuttle owing to the electronegativity difference of La and Zr. The charge transfers from La to Zr through the surrounding O 2p ligand, where the electrons in the highest occupied molecular orbitals of the [LaO6] octahedron filled unoccupied π orbitals of [ZrO6]. The as-induced internal electron shuttle in the bimetallic hydroxides primarily strengthened the formation of [MO6]···PO4 species (backdonation interaction). Further, the σP-O donation interaction between [LaO6] and [PO4] was clearly increased via intensification of the covalent coordination with O, as confirmed by the P K-edge XANES spectra for the as-used samples.
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Affiliation(s)
- Chao Xiang
- College of Environmental Science and Engineering , Beijing Forestry University , Beijing 100083 , China
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment , Tsinghua University , Beijing 100084 , China
| | - Hongjie Wang
- College of Environmental Science and Engineering , Beijing Forestry University , Beijing 100083 , China
| | - Qinghua Ji
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment , Tsinghua University , Beijing 100084 , China
| | - Gong Zhang
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment , Tsinghua University , Beijing 100084 , China
| | - Jiuhui Qu
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment , Tsinghua University , Beijing 100084 , China
- Key Laboratory of Drinking Water Science and Technology Research Centre for Eco-Environmental Sciences , Chinese Academy of Sciences , Beijing 100085 , China
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16
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Tran HN, Nguyen DT, Le GT, Tomul F, Lima EC, Woo SH, Sarmah AK, Nguyen HQ, Nguyen PT, Nguyen DD, Nguyen TV, Vigneswaran S, Vo DVN, Chao HP. Adsorption mechanism of hexavalent chromium onto layered double hydroxides-based adsorbents: A systematic in-depth review. JOURNAL OF HAZARDOUS MATERIALS 2019; 373:258-270. [PMID: 30925385 DOI: 10.1016/j.jhazmat.2019.03.018] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 02/05/2019] [Accepted: 03/04/2019] [Indexed: 06/09/2023]
Abstract
An attempt has been made in this review to provide some insights into the possible adsorption mechanisms of hexavalent chromium onto layered double hydroxides-based adsorbents by critically examining the past and present literature. Layered double hydroxides (LDH) nanomaterials are typical dual-electronic adsorbents because they exhibit positively charged external surfaces and abundant interlayer anions. A high positive zeta potential value indicates that LDH has a high affinity to Cr(VI) anions in solution through electrostatic attraction. The host interlayer anions (i.e., Cl-, NO3-, SO42-, and CO32-) provide a high anion exchange capacity (53-520 meq/100 g) which is expected to have an excellent exchangeable capacity to Cr(VI) oxyanions in water. Regarding the adsorption-coupled reduction mechanism, when Cr(VI) anions make contact with the electron-donor groups in the LDH, they are partly reduced to Cr(III) cations. The reduced Cr(III) cations are then adsorbed by LDH via numerous interactions, such as isomorphic substitution and complexation. Nonetheless, the adsorption-coupled reduction mechanism is greatly dependent on: (1) the nature of divalent and trivalent salts utilized in LDH preparation, and the types of interlayer anions (i.e., guest intercalated organic anions), and (3) the adsorption experiment conditions. The low Brunauer-Emmett-Teller specific surface area of LDH (1.80-179 m2/g) suggests that pore filling played an insignificant role in Cr(VI) adsorption. The Langmuir maximum adsorption capacity of LDH (Qomax) toward Cr(VI) was significantly affected by the natures of used inorganic salts and synthetic methods of LDH. The Qomax values range from 16.3 mg/g to 726 mg/g. Almost all adsorption processes of Cr(VI) by LDH-based adsorbent occur spontaneously (ΔG° <0) and endothermically (ΔH° >0) and increase the randomness (ΔS° >0) in the system. Thus, LDH has much potential as a promising material that can effectively remove anion pollutants, especially Cr(VI) anions in industrial wastewater.
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Affiliation(s)
- Hai Nguyen Tran
- Institute of Fundamental and Applied Sciences, Duy Tan University, Ho Chi Minh City 700000, Vietnam.
| | - Dong Thanh Nguyen
- Institute of Environmental Technology, Vietnam Academy of Science and Technology, Ha Noi, Vietnam
| | - Giang Truong Le
- Institute of Chemistry, Vietnam Academy of Science and Technology, Ha Noi, Vietnam
| | - Fatma Tomul
- Burdur Mehmet Akif Ersoy University, Faculty of Arts and Science, Chemistry Department, 15100 Burdur, Turkey
| | - Eder C Lima
- Institute of Chemistry, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil
| | - Seung Han Woo
- Department of Chemical and Biological Engineering, Hanbat National University, 125 Dongseodaero, Yuseong-Gu, Daejeon 305-719, Republic of Korea
| | - Ajit K Sarmah
- Department of Civil & Environmental Engineering, Faculty of Engineering, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Hung Quang Nguyen
- Institute of Fundamental and Applied Sciences, Duy Tan University, Ho Chi Minh City 700000, Vietnam
| | - Phuong Tri Nguyen
- Department of Chemistry, University of Montreal, Montreal, QC, Canada
| | - Dinh Duc Nguyen
- Department of Environmental Energy Engineering, Kyonggi University, Republic of Korea
| | - Tien Vinh Nguyen
- Faculty of Engineering and IT, University of Technology Sydney (UTS), Sydney, Australia
| | | | - Dai-Viet N Vo
- Faculty of Chemical & Natural Resources Engineering, Universiti Malaysia Pahang, Lebuhraya Tun Razak, Gambang 26300, Pahang, Malaysia
| | - Huan-Ping Chao
- Department of Environmental Engineering and R&D Center for Membrane Technology, Chung Yuan Christian University, Taoyuan, 32023, Taiwan.
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Jarrah N, Mu'azu ND, Zubair M, Al-Harthi M. Enhanced adsorptive performance of Cr(VI) onto layered double hydroxide-bentonite composite: Isotherm, kinetic and thermodynamic studies. SEP SCI TECHNOL 2019. [DOI: 10.1080/01496395.2019.1614955] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
Affiliation(s)
- Nabeel Jarrah
- Department of Chemical Engineering, Mutah University, Karak, Jordan
| | - Nuhu Dalhat Mu'azu
- Department of Environmental Engineering, College of Engineering, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Mukarram Zubair
- Department of Environmental Engineering, College of Engineering, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Mamdouh Al-Harthi
- Department of Chemical Engineering, King Fahd University of Petroleum & Minerals, Dhahran, Saudi Arabia
- Center of Research Excellences in Nanotechnology, King Fahd University of Petroleum & Minerals, Dhahran, Saudi Arabia
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18
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Coprecipitation Preparation of Cu/Zn/Al-Hydrotalcite-Like Compound for Copper Removal from Electroplating Wastewater. J CHEM-NY 2019. [DOI: 10.1155/2019/5347920] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Cu/Zn/Al-hydrotalcite-like compound (Cu/Zn/Al-HTlc) was prepared by the coprecipitation method with ZnII, AlIII cations solution, and electroplating wastewater containing CuII cation. The preparation conditions of Cu/Zn/Al-HTlc were optimized. The metal ion pollutants removal effect and iodide maximum adsorption capacity of Cu/Zn/Al-HTlc were also studied. The physicochemical properties of the Cu/Zn/Al-HTlc were analyzed by X-ray diffraction, FTIR, SEM, N2 adsorption-desorption isotherms, and TG-DTG. The results showed that Cu/Zn/Al-HTlc should be prepared with the ZnII-AlIII molar ratio of 1.5 : 1, pH = 11, and aged at room temperature for 0.5 d. Structural analysis showed that the Cu/Zn/Al-HTlc was a layered compound. CuII and other metal ion pollutants can also be successfully removed from electroplating wastewater in the preparation process of Cu/Zn/Al-HTlc and reached Chinese National Emission Standard (GB 21900-2008). The optimal adsorption condition of calcinated Cu/Zn/Al-HTlc for iodide was as follows: the solid-liquid ratio was 1 : 250, the pH value was 8, and the adsorption process was carried out at 25°C for 30 min. The saturated adsorption capacity reached 1000 mg·g−1 at the optimal adsorption condition. The main reason for this high-saturated adsorption capacity of Cu/Zn/Al-HTlc was that iodide penetrated into the layered structure of Cu/Zn/Al-HTlc by physical adsorption and CuII undergoes a specific redox reaction, producing CuI. Hence, coprecipitation synthetic technology and prepared Cu/Zn/Al-HTlc could be potentially used for electroplating wastewater treatment.
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