PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
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2024
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IF 6.9
Ping Zhang,Feiping Zhao,Penggang Li,Junhao Zheng,Weichun Yang,Qingzhu Li,Zhihui Yang
Electrocoagulation (EC) is a facile technique for removing arsenic (As) pollutants from different water matrices with high efficiency. In this work, a novel strategy of Mn-assisted Fe EC was developed to further enhance the removal efficiency of arsenite [As(III)] from wastewater. When 1 mM of MnCl 2 was added to an Fe-EC system, the As removal efficiency reached 99.99%, and the residual concentration was only 9 μg/L, which is lower than the World Health Organization’s limit for drinking water . The characteristics of the generated flocs by four different EC processes in Fe, Fe-Mn, Fe-As, and Fe-Mn-As systems were investigated. The results showed that Mn 2+ promoted the formation of FeOOH, FeO x , MnO x , FeHAsO 4 , and MnHAsO 4 through low crystallinity and a high surface area . Density functional theory simulation and crystal orbital hamiltonian population confirmed that the generated Fe-Mn flocs had a greater adsorption affinity for As(III) and arsenate [As(V)]. The possible reactions in the EC processes and reaction mechanisms were also hypothesised. The current work provides meaningful insights into understanding the mechanisms of Mn-assisted Fe-EC systems, and further confirms its potential for practical applications in As pollution treatment.
研究领域:
环境科学
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水处理工程
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DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2024
·Vol. 31
·期 18
·27037-27051
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IF 0
Sun Hongyu,Bao Qiongli,Chu Yutan,Li Yan,Shi Jiahao,Huang Yizong
Graphene-based material is widely used to remove arsenic from water due to its layered structure with high surface area. Here, we have successfully synthesized Fe-La bimetallic modified graphite sheet materials to more efficiently remove As(III) from aqueous solution. The results showed that Fe-La-graphite sheets (FL-graphite sheets) have a larger specific surface area (194.28 m 2 ·g −1 ) than graphite sheets (2.80 m 2 ·g −1 ). The adsorption capacity of FL-graphite sheets for As(III) was 51.69 mg·g −1 , which was higher than that of graphite sheets (21.91 mg·g −1 ), La-graphite sheets (26.06 mg·g −1 ), and Fe-graphite sheets (40.26 mg·g −1 ). The FL-graphite sheets conformed to the Freundlich and Dubinin–Radushkevich isotherm, and the maximum adsorption capacity was 53.62 mg·g −1 . The removal process obeys intra-particle diffusion and pore diffusion for As(III). The results of batch adsorption experiments and characterization analyses demonstrated that oxidation, ligand exchange, and inner sphere complexation mechanisms involved in the adsorption of FL-graphite sheets to As(III) in comparison with graphite sheets. In addition, electrostatic attraction mechanism was found vital in the adsorption. Ecotoxicity assessment revealed that FL-graphite sheets have little influence on rice germination and growth, but reduced the toxicity of As(III) to rice. Therefore, the FL-graphite sheets have good practical application value in purifying As(III) polluted water with litter ecotoxicity.
研究领域:
环境科学
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材料科学
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DOI
PubMed
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
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2020
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IF 6.155
Yuwei Ye,Zilong Jiang,Yangjun Zou,Hao Chen,Shengda Guo,Qiumin Yang,Liyong Chen
An eco-friendly and effective corrosion inhibitor (N-CDs) was acquired by hydrothermal method in methacrylic acid and ethyl(methyl)amine precursors. Afterwards, the weight loss and electrochemistry measurement were chosen to appraise the corrosion inhibition behavior of as-prepared N-CDs for Q235 steel in Cl − contained solutions. The change rules of EIS and Tafel data displayed that the as-prepared N-CDs revealed a high-efficiency protection for steel in all test environments. Meanwhile, the inhibition efficiency of steel reached up to 93.93 % (1 M HCl) and 88.96 % (3.5 wt% NaCl) at 200 mg/L of N-CDs. Furthermore, the N-CDs could form the adsorption film on steel surface to avoid the strong attack of Cl − . By analysis, the adsorption mechanism of as-prepared N-CDs on steel surface was physicochemical interaction , which strictly complied with the Langmuir adsorption model in both solutions.
研究领域:
材料科学
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电化学
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DOI
高影响因子
ENVIRONMENTAL RESEARCH
·
2020
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IF 5.715
Si Xu,Zuqi Zhong,Weizhen Liu,Hong Deng,Zhang Lin
Pollution and remediation of antimony in aquatic ecosystems have been paid increasing attention. In the present work, environmentally friendly nano-MgO was used for the first time to remove Sb(III) from the water system. The batch experiments indicated that the nano-MgO calcined at 400 °C (named 400-MgO) exhibited superior adsorption capacity for Sb(III). The adsorption isotherm was fitted well with the Freundlich model, and especially when the initial concentration is 15 mg‧L −1 , the adsorption capacity is as high as 140.1 mg‧g −1 . Researches through X-ray diffraction (XRD), Transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS) showed that the main removal mechanisms lie in the generation of Mg active sites, which is capable of coordinating Sb(III), during the hydration process of MgO, providing a nucleation center for the progressive production of MgSb 2 O 4 . As a whole, precipitation is the predominant mechanism for MgO to remove Sb(III). Over time, a part of MgO is hydrated to Mg(OH) 2 , and consequent chemisorption also helps to remove Sb(III). Our work has demonstrated that nano-MgO is a promising adsorbent for Sb(III) removal from contaminated water and provided new insights into the interaction mechanism between MgO and Sb(III).
研究领域:
环境科学
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化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
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2019
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IF 4.865
Jizhou Zhang,Xianfa Ma,Lei Yuan,Dongxing Zhou
Cd 2+ pollution in aquatic environments can pose a serious threat to human health. Biochar can remove Cd 2+ from aquatic environments, but the Cd 2+ adsorption capacity of conventional biochar is low, therefore, we focused on exploring the Cd 2+ adsorption capacity of modified biochar. In this study, KMnO 4 was used to modify vermicompost biochar (VBC), and static adsorption tests for Cd 2+ were carried out. The biochar properties and its adsorption efficiency toward Cd 2+ before and after modification were studied by kinetics and isotherm model fitting, scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS), Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). Additionally, an adsorption mechanism was discussed. The results showed that the KMnO 4 -modification resulted in a successful loading of the vermicompost biochar with MnO 2 , which greatly improved its adsorption capacity for Cd 2+ . The adsorption of Cd 2+ by VBC and MVBC was a spontaneous, endothermic, and monolayer chemical adsorption process . Mineral precipitation mechanism accounted for the largest proportion, and CdCO 3 was the main precipitate. After modification the proportion of surface precipitation and other mechanisms (π-electron coordination and the inner/outer sphere surface coordination) increased，while adsorption via cation exchange, oxygen-containing functional groups, physical adsorption and electrostatic attraction reduced. Hence, KMnO 4 modification has a significant effect on the Cd 2+ adsorption behavior of vermicompost biochar.
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING SCIENCE
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2021
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IF 4.311
Xuesong Jiang,Jian Shi,Chen Chen,Wangfeng Song,Boyuan Ban,Jingwei Li,Anshu Wang,Jian Chen
In this study, the flotation behavior and adsorption mechanism of quartz flotation using poly (propylene glycol) bis (2-aminopropyl ether) (PEA) with different carbon chain lengths as collectors were studied. The mineral properties and adsorption mechanism were analyzed using XRD, ICP-OES, FTIR, and XPS tests. The results show that the water solubility of the collector is negatively related to the chain length. The insertion of the ether bonds (C─O─C) and the two amine groups (─NH 2 ) improve the water solubility of PEA. Their collection capacity is proportional to the chain length and the insertion of the ether bonds hardly affects their collection capacity. PEA is attached to the quartz surface mainly by electrostatic adsorption, and to a less extent by hydrogen bond adsorption. Based on the above results, PEA-D400 can be used as a collector to separate low-grade quartz into products of different purity levels.
研究领域:
矿物加工工程
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表面化学
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2017
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IF 6.065
Zhangtao Li,Lu Wang,Jun Meng,Xingmei Liu,Jianming Xu,Fan Wang,Philip Brookes
Nanoscale zero-valent iron (NZVI) has a high adsorption capacity for heavy metals, but it forms aggregates easily. In this study, zeolite-supported nanoscale zero-valent iron (Z-NZVI) was synthesized from a simplified liquid-phase reduction of iron(III) salts which simultaneously adsorbed As(III), Cd(II) and Pb(II) from aqueous solution and soil. Scanning electron micrographs showed that aggregation was eliminated and the NZVI evenly dispersed onto the surface of zeolite. FTIR spectra reveal that NZVI was protected from oxidization on the surface of Z-NZVI. XRD and XPS patterns confirmed the formation of Cd(OH) 2 , Pb 0 , and FeAsO 4 in Z-NZVI after adsorption. The experimental maximum adsorption capacity of Z-NZVI was 11.52 mg As(III)/g, 48.63 mg Cd(II)/g, and 85.37 mg Pb(II)/g at pH 6, respectively, much higher than that of zeolite. Batch experiments indicate that various adsorption mechanisms including electrostatic adsorption, ionic exchange, oxidation, reduction, co-precipitation, and complexation coexisted with the selected heavy metals. Due to the formation of multiphase compounds on the Z-NZVI, the synergy and competition among heavy metals were concurrent. Most arsenic, cadmium and lead in the soil samples were immobilized after mixing with 30 g/kg Z-NZVI. These results suggest that Z-NZVI has great potential for treating water and soil multi-contaminated with heavy metals.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2021
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IF 7.312
Jie Huang,Bin Huang,Tianxiang Jin,Zhirong Liu,Dejuan Huang,Yong Qian
The extraction of U(VI) from nuclear wastewater is of great importance for environmental protection. In this work, we try to remove uranium ions from uranium-containing wastewater by electrosorption. In order to improve the adsorption capacity and selectivity of the adsorption materials, the complex of chitosan and phytic acid (CSPA) was used as electrode material. The experimental results showed that the introduction of phytic acid can efficiently improve the adsorption capacity, adsorption selectivity and reusability of chitosan. The maximum adsorption capacity of CSPA was 429.1 mg/g and the theoretical maximum sorption capacity reached up to 572.1 mg/g. Moreover, the electrosorption capacity of CSPA for U(VI) was 68.6% of the total electrosorption capacity in the presence of competitive ions. After 5 cycles of reuse, CSPA still maintained 86.6% of its initial sorption capacity. Furthermore, we found that the selective adsorption mechanism of uranium ions was related to the inner-sphere complexation between UO 2 2+ and the O atom of P O group according to the experimental analysis and the DFT calculation results. This work provided a novel strategy for effective removal of uranium (VI) from uranium-containing 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
Journal of Water Process Engineering
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2024
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IF 6.3
Heng Yu,Hongliang Zhang,Chenyang Zhang,Wei Sun,Mingjun Han,Rong Wang,Xin Wei,Songjiang Li
With the increased use of silver in industry, a lot of wastewater containing silver is produced. If this wastewater is not treated, it will seriously impact both the ecological environment and human life. In order to effectively remove Ag + from silver-containing wastewater, this study innovatively developed a natural mineral-based adsorption material (galena). The effects of reaction time, galena dosage, starting concentration, initial particle size, temperature, and solution pH on Ag + removal were first studied using batch studies. The outcomes demonstrated that the initial Ag + concentration of 50 mg/L reduced to 0.086 mg/L with the reaction duration of 15 min, the galena dose of 5 g/L, the initial particle size of −400 mesh (38 μm), the reaction temperature of 25 °C, and the pH of 5. The adsorption results show that the removal behavior of Ag + by galena is consistent with the pseudo-second-order adsorption kinetic model and the Freundlich isothermal adsorption model, with the maximum adsorption amount of 18.78 mg/g. Solution chemical analysis shows that in the Ag + -NO 3 2− -Pb 2+ -S 2− system, Ag + mainly reacts with S 2− and forms a precipitate at pH = 5–6. SEM-EDS, FT-IR, and XPS analysis also showed that S 2− and Ag + are bound together as Ag 2 S in the galena surface. Orbital hybridization of the 4d orbitals of Ag + with the S 2− 3p orbitals occurs during the adsorption process according to density functional theory (DFT) calculations. During the adsorption process, Ag + undergo charge transfer with S 2− in the surface of galena.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2019
·
IF 6.361
Muhammad Zaheer Afzal,Rengyu Yue,Xue-Fei Sun,Chao Song,Shu-Guang Wang
In this study, humic acid coated biochar (HA-BC) and chitosan were combined to prepare an adsorbent with enhanced reactivity for the removal of ciprofloxacin (CIP). With initial CIP concentrations of 250 mg/L, the maximum adsorbed amount was 154.89 mg/g. Removal rates reached equilibrium after 12 h, obeying the pseudo second-order kinetic model . Adsorption isotherm data was better fitted to the Langmuir isotherm model. The sorption capacity of humic acid-biochar/chitosan hydrogel beads (HBCB) decreased by 11.42%, 6.66%, 9.32%, and 23.92% in the presence of NaCl , NaNO 3 , Na 2 SO 4 , and Na 3 PO 4 , respectively. A complex mechanism was found to be responsible for the adsorptive removal of CIP including, hydrogen bonding , π-π electron donor–acceptor (EDA) interactions and hydrophobic interactions. After four regeneration steps, sorption capacity remained sufficient (61.23 mg/g). These removal results indicate that HBCB is durable and effective for long term CIP removal.
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 115
·114171-114182
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IF 3.289
Yanfang Huang,Wencui Chai,Guihong Han,Jiongtian Liu,Hongyang Wu,Shengpeng Su,Yijun Cao
The acid/base chemistry of hydrolysable Al(III) species with a clay (bentonite and kaolin) system was investigated at 35 °C in the expanded solution pH range from 1 to 9. The adsorption capacity (qe) and mechanism of Al(III) species on clays were examined by means of UV-Vis spectra, optical microscope, zeta potential testing, SEM, XPS and XRD analysis. The results demonstrate that the qe of Al(III) increases with increasing solution pH, and the maximum adsorptions of bentonite and kaolin are 13.64 mg g−1 and 1.06 mg g−1, respectively. Each Al(III) species offers a different contribution to the total adsorption capacity. The cation Al3+ is the dominant species below pH 4 and the anion Al(OH)4− is the main species above pH 6. The solution pH values change in the single clay or hybrid clay/Al(III) solution because of the acid–base dissolution and competitive adsorption of H+/OH− with Al(III) species. The particle sizes (d80) of the clays after adsorption at different pH were first associated with thermodynamics. The zeta potential variation of clays was first connected with the total charge numbers of Al(III) species in solution. Zeta potential, XPS and XRD studies indicate that charge neutralization and ion exchange dominate the adsorption process at lower pH and surface complexation and precipitation at higher pH.
研究领域:
环境科学
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化学
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DOI
高影响因子
ADVANCES IN POLYMER TECHNOLOGY
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2020
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IF 1.539
Yunlong Liu,Jie Guo,Zhuobing Xiao,Dazhao Peng,Ke Song
Separation and purification of active components from biomass by inorganic materials during the pretreatment process of hydrothermal conversion are studied in this work. The batch experiment results show that an initial solution pH of 6 favors chelerythrine adsorption, and the optimum adsorbent dosage is 2.0 g. The adsorption mechanism of ZSM-5 for chelerythrine is investigated by adsorption kinetics, isotherm adsorption models, and thermodynamics analysis. The results show that the kinetics data fit the pseudo-second-order model well (R2 = 0.9991), and the intraparticle diffusion model has 3 diffusion stages, preliminarily indicating that chemisorption plays a major role in the adsorption process, and the sorption mechanism includes intraparticle, external, and boundary diffusion. The adsorption isotherms agree well with the Langmuir model, indicating the occurrence of monolayer molecular adsorption during the adsorption process. Meanwhile, the maximum adsorption capacity is 2.327, 2.072, and 1.877 mg/g at different temperatures (288 K, 298 K, and 308 K), respectively. The thermodynamic data demonstrate that the adsorption process is exothermic and spontaneous in nature. These observed results clearly confirm that ZSM-5 has potential superior properties for the enrichment and purification of alkaloids during the pretreatment of biomass.
研究领域:
生物化学
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环境科学
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材料科学
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DOI
高影响因子
危险品化学品经营许可证（带存储）