JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY
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2021
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IF 2.262
Lili Yan,Siyu Jiang,Pinhua Rao,Guanghui Li,Zongdi Hao,Lei He,Shanliang Liu,Guofeng Shang
Rice hull biochar modified by ZnS nanocrystals (RBZ) was developed as an efficient absorbent for the removal of Cu(II) in aqueous solution. Response surface methodology (RSM) was applied for modeling and optimizing the performance of RBZ. The maximum adsorption capacity of RBZ toward Cu(II) through the Langmuir model fitting was 248.98 mg g−1, which was four times larger than that of rice hull biochar (RB). The adsorption kinetics of Cu(II) and XPS analysis revealed that the chemisorption process played the leading role when using RBZ. Through competition ions study, Pb(II), Cd(II), or Ca(II) can slightly reduce the adsorption of Cu(II). According to the Box Behnken design method, the analysis of variance results showed that the pH and adsorbent dosage had significant effects on the predicted responses of adsorption capacity and removal efficiency. When using the optimum conditions, pH 6, temperature 27 °C, and dosage 0.20 mg mL−1 for removing Cu(II) in solution, the maximum adsorption capacity and relatively higher removal efficiency could be obtained through the 3D response surface plots. The results demonstrated that RSM is feasible to achieve optimal conditions for adsorption capacity and removal efficiency simultaneously toward heavy metals from aqueous medium, and the interaction between them when using the biochar/ZnS composite.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
JOURNAL OF POLYMERS AND THE ENVIRONMENT
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2024
·Vol. 32
·期 7
·3326-3341
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IF 4.7
Wang Rui,Song Xin,Liu Li,Zhou Chao,Wu Guangfeng
Magnetic particles with active groups on their surfaces can be applied to wastewater purification to remove harmful ions, but the insufficient number of active groups on their surfaces tends to limit their removal rate of ions. Herein, we grafted different generations of dendritic macromolecular polyamidoamine (PAMAM) onto the magnetic chitosan microspheres (MCS) using ethylenediamine tetraacetic acid (EDTA) as core (MCEPs) for the removal of Cu (II). Firstly, 7 μm-sized MCS with good dispersibility was prepared by adjusting conditions such as glacial acetic acid content, emulsifier content and raw material ratio. Secondly, the effect of MCEPs generation, pH and contact time on the adsorption capacity were investigated. The adsorption experiments showed that the MCEPs had a high adsorption capacity, when the adsorbent was the second generation of MCEP (MCEP G2.0), the maximum adsorption capacity can up to 702.9 mg/g and the adsorption process can be completed in 60 min. Moreover, among various isotherms models, MCEP G2.0 was well-fitted by Langmuir adsorption isotherm. Also, adsorption kinetic studies proved that the adsorption mechanism of MCEP G2.0 adsorbent followed the pseudo-second-order kinetic model, demonstrating that the process was chemisorption. The adsorbent has renewability as well, after five adsorption cycles, its adsorption efficiency was still higher than 80%. Therefore, the adsorbent showed a superior adsorption capacity and renewability to remove Cu (II). Graphical
研究领域:
环境科学
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材料科学
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化学工程
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纳米技术
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DOI
高影响因子
Water
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2021
·Vol. 13
·期 13
·1732
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IF 3.103
Yuanyuan Yu,Yongjun Sun,Jun Zhou,Aowen Chen,Kinjal J. Shah
In this study, a high-efficiency magnetic heavy metal flocculant MF@AA was prepared based on carboxymethyl chitosan and magnetic Fe3O4. It was characterized by SEM, FTIR, XPS, XRD and VSM, and the Cu(II) removal rate was used as the evaluation basis for the preparation process. The effects of AMPS content, total monomer concentration, photoinitiator concentration and reaction time on the performance of MF@AA flocculation to remove Cu(II) were studied. The characterization results show that MF@AA has been successfully prepared and exhibits good magnetic induction characteristics. The synthesis results show that under the conditions of 10% AMPS content, 35% total monomer concentration, 0.04% photoinitiator concentration, and 1.5 h reaction time, the best yield of MF@AA is 77.69%. The best removal rate is 87.65%. In addition, the response surface optimization of the synthesis process of MF@AA was performed. The optimal synthesis ratio was finally determined as iron content 6.5%, CMFS: 29.5%, AM: 53.9%, AMPS: 10.1%. High-efficiency magnetic heavy metal flocculant MF@AA shows excellent flocculation performance in removing Cu(II). This research provides guidance and ideas for the development of efficient and low-cost flocculation technology to remove Cu(II) in wastewater.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
MOLECULES
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2021
·Vol. 26
·期 4
·978
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IF 4.412
Peng Liu,Hui Ruan,Tiantian Li,Jiaqi Chen,Fuqiu Ma,Duoqiang Pan,Wangsuo Wu
The low cost β-zeolite and ethylenediamine modified β-zeolite (EDA@β-zeolite) were prepared by self-assembly method and used for Cu(II) removal from contaminated aqueous solution. Removal ability of β-zeolite toward Cu(II) was greatly improved after ethylenediamine (EDA) modification, the removal performance was greatly affected by environmental conditions. XPS results illustrated that the amide group played important role in the removal process by forming complexes with Cu(II). The EDA@β-zeolite showed desirable recycling ability. The finding herein suggested that the proposed composite is a promising and suitable candidate for the removal of Cu(II) from contaminated natural wastewater and aquifer.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
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2024
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IF 4.1
Yong-peng Sun,Gang Wang,Ya-ling Guo,Xiao-yan Zhu
A novel absorbent called mercaptopropionyl wheat straw (MPWS) was prepared through alkali pretreatment and mercaptopropionyl modification for efficient removal of Cu(II) from aqueous solutions. Single factor experiments were conducted to investigate various parameters affecting the adsorption of Cu(II) with MPWS. Adsorption experiments including kinetics, isotherms, thermodynamics, as well as various characterization methods were employed to discuss the mechanism of Cu(II) uptake by MPWS in this study. The results showed that MPWS exhibited high removal capacity for Cu(II), achieving a maximum removal efficiency of 97.28 % under optimal conditions: oscillation rate at 150 rpm, temperature at 303 K, duration at 2 h, pH value at 6.0, and initial concentration of Cu(II) at 100 mg/L. The fitting results indicated that pseudo-second-order kinetic model better described the experimental data while Freundlich model provided a better fit for isothermal data. Thermodynamic calculations confirmed that the adsorptive process was spontaneous and endothermic. Characterization techniques such as FTIR spectroscopy SEM imaging, and EDS analysis confirmed chemisorption between Cu(II) ions and functional groups present on MPWS including sulfhydryl groups, amine groups, hydroxyl groups, and carboxyl groups. Overall, the main mechanisms governing Cu(II) uptake onto MPWS included coordination, ion exchange, electrostatic adsorption, and physical adsorption.
研究领域:
环境科学
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化学工程
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材料科学
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产品关联
DOI
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 59
·34151-34160
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IF 2.936
Changjiang Yu,Dashuai Zhang,Xinyu Dong,Qiang Lin
The reduction behavior of Fe3+ during the preparation of a zero-valent iron cocoanut biochar (ZBC8-3) by the carbothermic reduction method was analyzed. Fe3+ was first converted into Fe3O4, which was subsequently decomposed into FeO, and finally reduced to Fe0. A minor amount of γ-Fe2O3 was produced in the process. The isothermal thermodynamic data for the removal of Cu(II) over ZBC8-3 followed a Langmuir model. The Langmuir equation revealed a maximum removal capacity of 169.49 mg g−1 at pH = 5 for ZBC8-3. The removal of Cu(II) over ZBC8-3 fitted well to a pseudo-first-order equation, which suggested that the rate limiting step of the process was diffusion. The Cu(II) removal mechanism on ZBC8-3 involved the reduction of Cu(II) by Fe0 to produce Cu0 and Cu2O, while CC, C–O–, and –O–H formed a complex with Cu(II).
研究领域:
环境科学
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化学工程
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材料科学
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产品关联
DOI
PubMed
高影响因子
Journal of Macromolecular Science Part A-Pure and Applied Chemistry
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2024
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IF 2.1
Ping Jiang,Wan Liu,Jing Li,Yuan Gao
Straw and chitosan are underutilized raw materials, which could make a significant contribution to sustainable development. Herein, a novel chitosan-based hydrogel incorporating rice straw cellulose micro-fibrils (SCMF) was prepared to effectively remove Cu(II). FTIR and SEM showed that straw cellulose-g-poly (acrylic acid)/chitosan-g-poly (acrylic acid) interpenetrating polymer networks were prepared and the hydrogel SCCH had a 3D porous structure after cross-linking with AA. The swelling properties of SCCH were studied and compared in various pH solution. The results indicated that SCCH replayed pH responsibility, which had the largest and smallest swelling capacity at pH9.18 and pH4.00 respectively. The pseudo-second-order kinetic model can be effectively used to evaluate swelling kinetics of hydrogels. The effects of contact time and initial concentration on Cu(II) ion removal were investigated. The equilibrium adsorption capacity (Qe) was 209.2 mg/g and the obtained results indicated that the adsorption kinetics conformed to the pseudo-second-order. Chemical adsorption combined with porous physical adsorption endowed SCCH excellent swelling and adsorption properties. Tensile, compression, bending and twisting test convinced that SCMF played a significant role on the improvement of mechanical strength. This novel 3D porous chitosan-based hydrogel was identified to be a promising sorbent with advantages of excellent sorption and mechanical properties.
研究领域:
环境科学
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高分子科学
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材料工程
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化学工程
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可持续发展
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DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2019
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IF 6.044
Jianming Wu,Xi Cheng,Yulin Li,Guisheng Yang
In this study, Fe 3 O 4 -nanoparticles-contained polyamide 6 (PA 6) microparticles (FP) were developed by a first dispersion of Fe 3 O 4 -nanoparticles in ε-caprolactam (CL) monomer in the presence of polystyrene (PS) and a subsequent in situ CL open polymerization into PA 6, followed by PS removal. The FP microparticles (as magnetic separation material) and nanochitin (n-CT, as an effective metal-cation natural adsorbent) were then in situ encapsulated into poly(vinyl alcohol)-enhanced chitosan hybrids (PVA/CTS) to form biodegradable nanocomposite hydrogels (FPCC) with magnetic separation ability. The FPCC hybridized hydrogels enabled about 1.7-fold Cu(II) adsorption capacity as compared to the pure PVA/CTS hydrogels with a Cu(II) adsorption value of 38.7 mg/g. More attractively, the adsorption equilibrium could be achieved within 10 min, which is quicker than many previous adsorbents. Furthermore, simulation results indicated that Cu(II) adsorption behaviors of the hybrid hydrogels conform to a pseudo-second-order kinetic model and a Langmuir isotherm model.
研究领域:
材料科学
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环境工程
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纳米技术
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）