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Yan C, Sun Q, Zhang J, Fu H, Gao H, Liao Y. Efficient removal of cesium ions using Prussian blue loaded on magnetic porous biochar synthesized by one-step calcination. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:125526-125539. [PMID: 37999846 DOI: 10.1007/s11356-023-31097-0] [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: 08/11/2023] [Accepted: 11/14/2023] [Indexed: 11/25/2023]
Abstract
Prussian blue (PB) is widely used for the selective removal of radioactive cesium ions (Cs+) from aqueous solutions. Due to its small size and easy dispersion in water, PB requires a carrier that is both inexpensive and easily separable. Magnetic porous biochar (MPBC) was formed by activating starch with FeCl3 through a one-step calcination method. MPBC can be used as a carrier for Prussian blue, which is easily separated from the solution. This composite material (PB/MPBC) has a rich pore structure and maintains effective surface area, which can facilitate the penetration of Cs+ into the adsorbent. Besides, PB/MPBC exhibits high selectivity and good adsorption capacity achieving a large removal capacity of 101.43 mg/g. Thus, this study provides a novel approach for preparing composites with efficient removal of Cs+.
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Affiliation(s)
- Changhan Yan
- Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, College of Chemistry and Chemical Engineering, China West Normal University, Nanchong, 637000, Sichuan, China
| | - Qihang Sun
- Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, College of Chemistry and Chemical Engineering, China West Normal University, Nanchong, 637000, Sichuan, China
| | - Juan Zhang
- Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, College of Chemistry and Chemical Engineering, China West Normal University, Nanchong, 637000, Sichuan, China
| | - Hongquan Fu
- Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, College of Chemistry and Chemical Engineering, China West Normal University, Nanchong, 637000, Sichuan, China
| | - Hejun Gao
- Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, College of Chemistry and Chemical Engineering, China West Normal University, Nanchong, 637000, Sichuan, China.
- Institute of Applied Chemistry, China West Normal University, Nanchong, 637000, Sichuan, China.
| | - Yunwen Liao
- Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, College of Chemistry and Chemical Engineering, China West Normal University, Nanchong, 637000, Sichuan, China
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Liu X, Wu J, Wang J. Electro-adsorption of Cs(I) ions from aqueous solution by capacitive deionization using ACC/MoO 3 composite electrode. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 865:161110. [PMID: 36586692 DOI: 10.1016/j.scitotenv.2022.161110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 12/03/2022] [Accepted: 12/17/2022] [Indexed: 06/17/2023]
Abstract
The separation of Cs+ from radioactive wastes is of paramount importance, but still a challenge. In this paper, ACC/MoO3 composite electrode was prepared and used for the separation of Cs+ by capacitive deionization (CDI). The electrode materials were characterized by SEM-EDS, FTIR, XPS before and after adsorption experiments. The composite electrode was composed of ACC and hexagonal tunnel structure of MoO3, which had a mesoporous structure. The specific surface area, average pore diameter, total pore volume and maximal specific capacitance were 170.4 m2 g-1, 2.127 nm, 0.906 cm3 g-1 and 76.3 F g-1, respectively. The adsorption kinetics, isotherms, and the mass transfer process were analyzed, and the possible adsorption mechanism was proposed. The removal efficiency of Cs+ increased with the increase of voltage and the decrease of Cs+ concentration, which reached 44.7 % after 240 min when voltage was 1.2 V and Cs+ concentration was 5 mg L-1. The Cs+ adsorption onto the ACC/MoO3 composite was multi-layer adsorption and the adsorption to active sites (AAS) was the rate-limiting step. Overall, the ACC/MoO3 composite was a potential electrode for Cs+ separation.
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Affiliation(s)
- Xiaojing Liu
- Institute of Agricultural Resource and Environmental Sciences, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China; Laboratory of Environmental Technology, INET, Tsinghua University, Beijing 100084, China
| | - Jinling Wu
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing 100084, China; Beijing Key Laboratory of Radioactive Waste Treatment, Tsinghua University, Beijing 100084, China
| | - Jianlong Wang
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing 100084, China; Beijing Key Laboratory of Radioactive Waste Treatment, Tsinghua University, Beijing 100084, China.
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Younes H, Rahman MM, Hong H, AlNahyan M, Ravaux F. Capacitive deionization performance of asymmetric nanoengineered CoFe 2O 4 carbon nanomaterials composite. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:32539-32549. [PMID: 36469268 DOI: 10.1007/s11356-022-24516-1] [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: 07/04/2022] [Accepted: 11/28/2022] [Indexed: 06/17/2023]
Abstract
Capacitive deionization (CDI) is a relatively new technique that uses electric double layer (EDL) effects, high-affinity chemical groups, redox-active materials, and membrane capacitive electrosorption principle for the desalination. In this paper, hydrothermal synthesis of cobalt ferric oxide (CFO) metal oxide nanoparticles (NPs) coupled with the vacuum filtration method, or the freeze-drying method is used to fabricate high-performance nanocomposites: CFO-graphene, CFO-CNTs, and CFO-3DrGO. Two times of hydrothermal reaction methods were conducted to fabricate the CFO-3DrGO nanoengineered as a pseudocapacitive/EDL electrode. The results have demonstrated that the SAC of CFO-3DrGO/CFO (64.5 mg g-1) is greater than that of the CFO-graphene/CFO (55.16 mg g-1) and CFO-CNTs/CFO (21.5 mg g-1) due to the better surface area of the CFO-3DrGO nanocomposite (330 m2 g-1). The higher surface area of the CFO-3DrGO is due to the porous and interconnected 3D structure of the 3DrGO, and it provides a larger surface area to form EDL capacitance. In addition, the added porous 3DrGO entangled with the spinel crystals (CoFe2O4) in the composite allowed for a quick ion diffusion across the interconnected open macroporous structures.
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Affiliation(s)
- Hammad Younes
- Department of Electrical Engineering, South Dakota Mines, Rapid City, SD, 57701, USA.
| | - Md Mahfuzur Rahman
- Department of Industrial and Production Engineering, Jashore University of Science and Technology (JUST), Jashore, 7408, Bangladesh
| | - Haiping Hong
- Department of Electrical Engineering, South Dakota Mines, Rapid City, SD, 57701, USA
| | - Maryam AlNahyan
- Department of Mechanical Engineering, Khalifa University of Science and Technology, P.O. Box 127788, Abu Dhabi, United Arab Emirates
| | - Florent Ravaux
- Department of Mechanical Engineering, Khalifa University of Science and Technology, P.O. Box 127788, Abu Dhabi, United Arab Emirates
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Shuaib U, Hussain T, Ahmad R, Imranullah M, Amjad M, Yasin A, Shakir I, Kang DJ. Novel synthesis of nickel oxide-copper hexacyanoferrate binary hybrid nanocomposite for high-performance supercapacitor application. J Solid State Electrochem 2022. [DOI: 10.1007/s10008-022-05357-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Cheng X, Chen C, Hu Y, Guo X, Wang J. Photosynthesis and growth of Amaranthus tricolor under strontium stress. CHEMOSPHERE 2022; 308:136234. [PMID: 36041533 DOI: 10.1016/j.chemosphere.2022.136234] [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: 07/28/2022] [Revised: 08/22/2022] [Accepted: 08/24/2022] [Indexed: 06/15/2023]
Abstract
Amaranthaceae are effective plants for cleaning soil contaminated by heavy metals and radionuclides. In this paper, Amaranthus tricolor was used to investigate the response of the plant photosynthesis to various concentration of strontium ions (0.2, 0.6, 3 and 6 mM), in order to determine the possibility of A. tricolor to remediate strontium contamination. The results showed that strontium ions (0.2-6 mM) had effect on light energy conversion and utilization in A. tricolor. Low level of strontium (0.2 mM) promoted the energy utilization in A. tricolor, while higher Sr concentration (3 mM or higher) increased the excess light energy in the plants. Under strontium stress of 6 mM, the acceptor side of PSII in A. tricolor leaves was more vulnerable to strontium stress than the donor side. Furthermore, strontium stress led to accumulation of QA- and block in QB downstream of the electron transfer chain in PSII of A. tricolor leaves. The tolerance ability of A. tricolor to strontium and remediation is also reflected in its biomass and strontium content in plants. Strontium at 3 mM or below promoted the growth of A. tricolor, while higher concentration inhibited the plant growth, but without obvious wilting or curling of leaves. The maximal dry weight increased by 36.29% in shoots, and 60.14% in roots when the spiked-strontium concentration reached 0.2 mM. The maximal strontium content achieved 8.75 mg/g dry wt in shoots, and 1.71 mg/g dry wt in roots respectively, when strontium concentration was 6 mM. Transfer factors (TFs: ratio of Sr content in shoots to that in roots) of strontium in A. tricolor ranged from 2.85 to 5.93, while bio-concentration factors (BCFs: ratio of Sr content in shoots to that in solutions) ranged from 22.57 to 49.66. In summary, A. tricolor showed the excellent potential to remediate strontium contamination.
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Affiliation(s)
- Xuening Cheng
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing, 100084, PR China
| | - Can Chen
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing, 100084, PR China; Beijing Key Laboratory of Radioactive Waste Treatment, INET, Tsinghua University, Beijing, 100084, PR China
| | - Yuming Hu
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing, 100084, PR China
| | - Xiliang Guo
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing, 100084, PR China; China Institute for Radiation Protection, Taiyuan, 030006, Shanxi, China
| | - Jianlong Wang
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing, 100084, PR China; Beijing Key Laboratory of Radioactive Waste Treatment, INET, Tsinghua University, Beijing, 100084, PR China.
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Wang J, Guo X. Rethinking of the intraparticle diffusion adsorption kinetics model: Interpretation, solving methods and applications. CHEMOSPHERE 2022; 309:136732. [PMID: 36223824 DOI: 10.1016/j.chemosphere.2022.136732] [Citation(s) in RCA: 55] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Revised: 08/25/2022] [Accepted: 10/01/2022] [Indexed: 06/16/2023]
Abstract
Adsorption is a widely used unit process in various fields, such as chemical, environmental and pharmaceutical, etc. The intraparticle diffusion adsorption kinetics model is one of the most widely used adsorption kinetics models. However, the application and solving method of this model have yet to be discussed. This model has two forms (qt = kt1/2 and qt = kt1/2 + constant, where qt is the adsorption capacity at time t, k and constant are the model parameters), which have not been unified yet. Moreover, the interpretation of this kinetics model lacks a theoretical basis (if the line passes through the origin point (0, 0), the adsorption is dominated by the intraparticle diffusion; if not, it is a multiple adsorption process). In this study, we analyzed the proper equations of the intraparticle diffusion model and their applications, discussed the interpretation of the mass transfer steps revealed by this model, and provided the solving methods. The result indicated that the piecewise function qt = k1t1/2 (0 ≤ t ≤ t1); qt - qt = t1 = k2(t - t1)1/2 (t1 < t ≤ t2) is the proper form of this model. The adsorbate diffusion in the pores inside the adsorbent is the mass transfer step revealed by this model. The statistical parameters should be used to evaluate the fitting results instead of judging whether the model lines pass through the origin point (0, 0). We provide the solving methods to use the Origin and Microsoft EXCEL software to solve the model. Our study established the method for application of the intraparticle diffusion model.
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Affiliation(s)
- Jianlong Wang
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing, 100084, PR China; Beijing Key Laboratory of Radioactive Waste Treatment, Tsinghua University, Beijing, 100084, PR China.
| | - Xuan Guo
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing, 100084, PR China
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Separation and Removal of Radionuclide Cesium from Water by Biodegradable Magnetic Prussian Blue Nanospheres. Processes (Basel) 2022. [DOI: 10.3390/pr10122492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
As the main component of radioactive wastewater, the cesium ion has seriously endangered the environment and human health. Prussian blue nanoparticles (PB NPs) are used as adsorbents for the purification of cesium-containing wastewater because of their ability to selectively adsorb cesium ions. In this work, novel magnetic Prussian blue nanospheres (MPBNs) were developed from polylactic acid nanospheres as a carrier, loaded with Fe3O4 nanoparticles (Fe3O4 NPs) inside and PB NPs outside for the removal of cesium ions with the help of magnetic separation. Meanwhile, the effects on the adsorption efficiency of MPBNs, such as pH, time, temperature and initial concentration of cesium ion solution, were studied. The adsorption isotherms, kinetic models and adsorption thermodynamics were investigated to research the absorption mechanism. The results showed that MPBNs were spherical with a rough surface, and their particle size, iron content and saturation magnetization were 268.2 ± 1.4 nm, 40.01% and 41.71 emu/g, which can be recovered by magnetic separation. At 293 K, MPBNs could reduce the cesium ion solution from 40 mg/L to 4.8 mg/L, and its cesium ion removal rate and adsorption capacity were 82.46% and 16.49 mg/g, respectively. The optimum pH of MPBNs for cesium ion adsorption was 5~9, the adsorption equilibrium time was 60 min, and the maximum adsorption capacity was 17.03 mg/g. In addition, MPBNs were separated rapidly by an external magnetic field, and the adsorption process was an endothermic reaction. The adsorption isotherm and kinetics of MPBNs were in accordance with the Freundlich model and quasi-second-order fitting model, respectively, and the adsorption process of MPBNs was controlled by the diffusion step in particles. Notably, these MPBNs could be effectively separated from water by a magnetic field, facilitating engineering applications in cesium-containing wastewater.
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Zhuang S, Zhu K, Xu L, Hu J, Wang J. Adsorption of Co 2+ and Sr 2+ in aqueous solution by a novel fibrous chitosan biosorbent. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 825:153998. [PMID: 35192812 DOI: 10.1016/j.scitotenv.2022.153998] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Revised: 02/13/2022] [Accepted: 02/15/2022] [Indexed: 06/14/2023]
Abstract
In this study, a novel fibrous chitosan biosorbent was prepared using LiOH/KOH/urea/H2O (4.5:7:8:80.5 by weight) as spinning solvent. The fibrous chitosan exhibited a higher adsorption capacity and a faster adsorption rate for Co2+ and Sr2+, compared with spherical chitosan due to its high specific surface area (16.9 m2 g-1), uniform fineness (24.1 μm), and good mechanical strength. The adsorption capacity of fibrous chitosan for Co2+ and Sr2+ was 31.3 mg g-1 and 20.0 mg g-1, respectively, which was higher than that of spherical chitosan (22.5 mg g-1for Co2+ and 8.9 mg g-1 for Sr2+). The coordination between -NH2/-OH of chitosan and the nuclide ions was the rate-limiting step. The improvement of adsorption performance was due to the higher specific surface area which increased the exposure degree of functional groups (adsorptive sites). This new wet-spun fibrous chitosan biosorbent showed great potential in the adsorptive removal of nuclides ions from aqueous solution.
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Affiliation(s)
- Shuting Zhuang
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing 100084, PR China
| | - Kunkun Zhu
- State Key Laboratory of New Textile Materials and Advanced Processing Technologies, Wuhan Textile University, Wuhan 430200, PR China
| | - Lejin Xu
- Department of Nuclear Engineering and Technology, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, PR China
| | - Jun Hu
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing 100084, PR China
| | - Jianlong Wang
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing 100084, PR China; Beijing Key Laboratory of Radioactive Waste Treatment, INET, Tsinghua University, Beijing 100084, PR China.
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Xiang S, Mao H, Geng W, Xu Y, Zhou H. Selective removal of Sr(II) from saliferous radioactive wastewater by capacitive deionization. JOURNAL OF HAZARDOUS MATERIALS 2022; 431:128591. [PMID: 35247739 DOI: 10.1016/j.jhazmat.2022.128591] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 02/21/2022] [Accepted: 02/24/2022] [Indexed: 06/14/2023]
Abstract
90Sr-containing radioactive wastewater during Fukushima nuclear accident (FNA) aroused extensive consideration for its disposal. Massive coexisted Na+ ions seriously inhibited Sr2+ removal, aggravating the expenditure of radioactive wastewater treatment. Herein, a chestnut shell derived porous carbon material modified with aryl diazonium salt (ADS) of sodium 4-aminoazobenzene-4'-sulfonate (SPAC) was developed as capacitive deionization electrode for selective removal of Sr2+ from saliferous radioactive wastewater. Based on ADS modification, the Sr2+ electrosorption capacity of SPAC electrode was improved to 33.11 mg g-1 with fast ion removal rate of 2.89 mg g-1 min-1, comparing with only 16.10 mg g-1 before modification. The isothermal adsorption and kinetics by SPAC electrode fitted well with Langmuir and pseudo-second-order model, achieving a maximum Sr2+ electrosorption capacity of 58.21 mg g-1, superior cycling stability, and excellent charge efficiency (77.63%). Fascinatingly, the SPAC electrode exhibited superhigh Sr2+ selectivity of 70.65 against Na+ in Na+-Sr2+ mixed solution with molar ratio of Na+:Sr2+ as 20:1. Density functional theory (DFT) simulation, combining with electrochemical and spectral analyses, revealed that the high overlap of electron cloud between Sr2+ ion and anionic sulfonic group (-SO3-) provided SPAC with remarkable selectivity of Sr2+ ion, and illustrated the ion-swapping mechanism of Sr2+ selectivity.
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Affiliation(s)
- Shuhong Xiang
- Key Laboratory of Materials Physics, Centre for Environmental and Energy Nanomaterials, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei 230031, PR China; Department of Materials Science and Engineering, University of Science and Technology of China, Hefei 230026, PR China
| | - Hengjian Mao
- Key Laboratory of Materials Physics, Centre for Environmental and Energy Nanomaterials, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei 230031, PR China; Department of Materials Science and Engineering, University of Science and Technology of China, Hefei 230026, PR China
| | - Wusong Geng
- Key Laboratory of Materials Physics, Centre for Environmental and Energy Nanomaterials, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei 230031, PR China
| | - Yingsheng Xu
- Key Laboratory of Materials Physics, Centre for Environmental and Energy Nanomaterials, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei 230031, PR China; Department of Materials Science and Engineering, University of Science and Technology of China, Hefei 230026, PR China
| | - Hongjian Zhou
- Key Laboratory of Materials Physics, Centre for Environmental and Energy Nanomaterials, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei 230031, PR China; Department of Materials Science and Engineering, University of Science and Technology of China, Hefei 230026, PR China.
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Lin J, Zhang Y, Zhang Q, Shang J, Deng F. Enhanced adsorption properties of organic ZnCr-LDH synthesized by soft template method for anionic dyes. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:48236-48252. [PMID: 33905058 DOI: 10.1007/s11356-021-14035-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 04/16/2021] [Indexed: 06/12/2023]
Abstract
Organic ZnCr-LDH (ST-LDH) was synthesized by a facile one-step hydrothermal technique using methyl orange (MO) as a soft template agent, which can efficiently remove methyl orange (MO), Congo red (CR), and orange II (OII) from aqueous solution. The microstructure of ST-LDH by modifying changed obviously, from the cellular structure to the stacking structure formed by the face-face contact of hydrotalcite nanosheets, which resulted in much more exchangeable nitrate ions to remain in the interlayer space. The pre-insertion of benzene sulfonate as a pillar expanded the interlayer gallery, which facilitated the pollutant anions (MO, CR, and OII) into the interlayer of LDH in the subsequent adsorption process. The maximum adsorption capacity of ST-LDH for MO, CR, and OII was 4200.8 mg/g, 1252.0 mg/g, and 1670.6 mg/g, respectively, which is approximately 1.86 times, 1.8 times, and 2.32 times that of the pristine NO3-LDH, respectively. The removal mechanism of anionic dyes was determined as anion exchange between NO3- anions and dye molecules. The adsorption behavior for MO and OII is multilayer adsorption, while the adsorption behavior for CR is monolayer adsorption. The adsorption process mainly was controlled by the chemical bonding between the dye molecules and adsorbent active sites. The LDH can be effectively regenerated by photocatalysis after MO adsorption. The ST-LDH has a great potential to be used as a high-efficient adsorbent to remove anionic dyes from aqueous solution. The schematic illustration of the synthetic process of soft template agent modified and unmodified hydrotalcites by one-pot hydrothermal method and the adsorption process of MO by ST-LDH were shown in Fig. 12. Modified hydrotalcite (ST-LDH) was prepared using methyl orange (MO) as a soft template agent. Compared with unmodified hydrotalcite (NO3-LDH), the insertion of benzene sulfonate anions into the hydrotalcite layer resulted in the increase of the interlayer spacing from 8.269 to 8.654Å. The LDH host structure pre-intercalated by benzene sulfonate anions evolved into pillared materials in interlayer; benzene sulfonate anions as a column expanded the interlayer spacing of (003) base plane, which facilitated the pollutant anions (MO, CR, and OII) into the interlayer of ST-LDH and exchanged with NO3- anion in the subsequent adsorption process. It can be inferred that in the process of modification hydrotalcite by benzene sulfonate, a small amount of benzene sulfonate anions pre-inserted into the gallery of hydrotalcite with a monolayer model in the process of hydrotalcite modification, and its inclination angle is calculated to be about 29.1°. After ST-LDH sample adsorbed the MO molecules, dye molecules intercalated into the LDH host, and successful exchange with NO3- anions, the d003 value increased to 24.78 Å. A large amount of MO- anions were intercalated into the gallery of ST-LDH with a bilayer model according to the Freundlich isotherm model, and the tilting angle increases to 53.6°. The adsorption capacity of MO by ST-LDH was significantly enhanced to 4200.8 mg/g, which was much higher than that of NO3-LDH (2252.8 mg/g). Schematic illustration of the synthetic process of LDH materials and adsorption process of MO by ST-LDH.
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Affiliation(s)
- Jia Lin
- School of Chemistry and Chemical Engineering, Henan Key Laboratory of Coal Green Conversion, Henan Polytechnic University, Jiaozuo, 454000, China
| | - Yude Zhang
- School of Chemistry and Chemical Engineering, Henan Key Laboratory of Coal Green Conversion, Henan Polytechnic University, Jiaozuo, 454000, China.
- Collaborative Innovation Center of Coal Work Safety of Henan Province, Jiaozuo, 454000, China.
- Wuxi Feile High-performance Materials Co. Ltd., Wuxi, 214000, China.
| | - Qian Zhang
- School of Chemistry and Chemical Engineering, Henan Key Laboratory of Coal Green Conversion, Henan Polytechnic University, Jiaozuo, 454000, China.
- Collaborative Innovation Center of Coal Work Safety of Henan Province, Jiaozuo, 454000, China.
- Wuxi Feile High-performance Materials Co. Ltd., Wuxi, 214000, China.
| | - Jinli Shang
- School of Chemistry and Chemical Engineering, Henan Key Laboratory of Coal Green Conversion, Henan Polytechnic University, Jiaozuo, 454000, China
| | - Fuyao Deng
- School of Chemistry and Chemical Engineering, Henan Key Laboratory of Coal Green Conversion, Henan Polytechnic University, Jiaozuo, 454000, China
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