Desalination and Water Treatment
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2024
·Vol. 57
·期 59
·28947-28956
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IF 1
Qiao Wang,Guang-shan Zhang,Han Chen,Peng Wang
A specially designed combined process of pre-oxidation and nanofiltration membrane was utilized to remove As(III) in the contaminated water without reagent addition and sediment creation in this work. Different parameters that affected the rejections of As(III) and As(V) were discussed, including the initial concentration, pH of the feed, and the cross-flow filtration pressure. The rejection of As(III) was over 70% which was restricted to the high initial feed concentration, while it was around 40% under the other conditions. Whereas, the rejection of As(V) maintained above 95% in all tests. As a result, As(III) was first pre-oxidized before membrane filtration. The ozone and aeration oxidation methods were used to oxidize As(III). The effects of aeration time and oxidation time were studied. The experimental results indicated that the rejection of As(III) was increased to over 90% after pre-oxidation, and the permeate could meet the drinking water standard for As in China. Particularly, the aeration took a much longer oxidation time than ozone, but it was still a more suitable method as the pre-oxidation process because of its safety and easy operability.
研究领域:
环境工程
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水处理技术
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膜分离
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污染物控制
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高影响因子
Journal of Water Process Engineering
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2025
·
IF 6.7
Xixiang Liu,Xiurong Chen,Yongming Luo,Caiyun Han,SuFang He
Much research has focused on the removal of individual contaminants such as As(V) or Cr(VI) from wastewater. However, limited efforts have been devoted to their simultaneous removal in binary systems. This is largely due to the complexity of wastewater matrices and the similar chemical characteristics of As(V) and Cr(VI). In this study, La-modified UiO-66 was synthesized by a one-pot method and employed as a multifunctional adsorbent to simultaneously remove As(V) and Cr(VI) via batch experiments. Characterization results demonstrated that La was successfully grafted onto UiO-66 through Zr-ligand (O)-La and Zr-ligand (O)-Zr linkages, while the fcu structural topology and microporous nature of UiO-66 were well remained. For simultaneous uptake of As(V) and Cr(VI), a synergistic effect of Cr(VI) was observed on As(V) removal, whereas As(V) exhibited an inhibitory effect on Cr(VI) adsorption. Compared with the single component system, the adsorption capacity of As(V) in the binary system increased by approximately 26 %, while the adsorption capacity of Cr(VI) decreased by about 20 %. The enhanced uptake of As(V) was attributed to the formation of a new Cr As complex compound between adsorbed Cr(III) and As(V). In contrast, the inhibitory influence of As(V) on Cr(VI) adsorption was ascribed to the strong affinity of As(V) for the active adsorption sites. Overall, these results demonstrate that La-modified UiO-66 is a promising candidate for the simultaneous removal of As(V) and Cr(VI) in binary systems, particularly under conditions of elevated As(V) concentration.
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高影响因子
Journal of Water Process Engineering
·
2024
·
IF 6.3
Weimin Chen,Renjian Deng,Yilin Chen,Chuang Wang,Baolin Hou,Saijun Zhou,Andrew Hursthouse
Arsenic and antimony removal technology have received significant attention due to their considerable danger to aquatic ecosystems. In this study, we designed HCO–(Fe 3 O 4 ) x adsorbents with substantial functional groups, ample pore spaces, and considerable surface area , specially tailored for the simultaneous adsorption of pentavalent arsenic (As( V )) and pentavalent antimony (Sb(V)). The adsorption performance of HCO–(Fe 3 O 4 ) x was subjected variably to the Ce/Fe molar ratio (CFMR), solution pH, and co-existing anions (SO 4 2− , PO 4 3− , SiO 3 2− ). The affinity order of As(V) and Sb(V) onto HCO–(Fe 3 O 4 ) x in binary systems was pH-dependent. At a pH of 2.0, Sb( V ) exhibited stronger adsorption than As(V), whereas the opposite trend occurred at pH levels above 4.0. Analysis of the kinetic data revealed the pseudo-second-order kinetic model was the most appropriate, indicating that chemical adsorption was the predominant mechanism. Notably, the formation of inner-sphere complexes led to a higher adsorption rate for As( V ) compared to Sb(V), attributed to a lower energy barrier of 0.863 eV, facilitating the breakdown of the Fe O bond in As(V)'s asymmetric tetrahedral structure. Various analyses (FTIR, XRD, and XPS) demonstrated that adsorption mechanisms involved multiple processes like hydrogen bonding , ligand exchange, electrostatic attraction, and complexation. The primary contributions for the adsorption of As( V ) and Sb(V) were the inner-sphere complex of cerium , oxygen and arsenic atoms (Ce O As) and the outer-sphere complex of iron, oxygen and antimony atoms (Fe O Sb), respectively, indicating significant differences in the mechanisms. These findings underscored the potential of HCO–(Fe 3 O 4 ) x in mitigating As( V ) and Sb(V) water pollution, emphasizing its considerable promise as an effective remediation agent.
研究领域:
环境化学
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水污染治理
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吸附科学
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环境功能材料
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重金属去除
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DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2016
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IF 5.886
Li Cui,Ying-Jiao Zhang,Wei E. Huang,Bi-Feng Zhang,Francis L. Martin,Jun-Yi Li,Kai-Song Zhang,Yong-Guan Zhu
Bacterial antibiotic resistance poses a threat to global public health. Restricted usage of antibiotics does not necessarily prevent its continued emergence. Rapid and sensitive screening of triggers, in addition to antibiotic, and exploring the underlying mechanism are still major challenges. Herein, by developing a homogeneous vacuum filtration-based bacterial sample fabrication enabling high surface-enhanced Raman scattering (SERS) reproducibility across multiple bacterial samples and negating interfering spectral variations from inhomogeneous sample geometry and SERS enhancement, SERS was employed to study heavy metal arsenic [As(V)]-mediated antibiotic resistance in a robust, sensitive, and rapid fashion. Independent and robust spectral changes representing phenotypic bacterial responses, combined with multivariate analysis, clearly identified that As(V) enhanced antibiotic resistance to tetracycline (Tet). Similar spectral alteration profile to As(V) and Tet indicated that cross-resistance, whereby As(V)-induced bacterial resistance simultaneously blocked Tet action, could account for the enhanced resistance. The sensitive, robust, and rich phenotypic profile provided by SERS, combined with additional advantages in imposing no need to cultivate bacteria and single-cell sensitivity, can be further exploited to evaluate resistance-intervening factors in real microbiota.
研究领域:
分析化学
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微生物学
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环境科学
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生物技术
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DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Ge Yan,Haiwei Jiang,Mingxiang Xie
Heavy metal separation and recovery from hyperaccumulators are crucial to promote the industrialization of phytoremediation and prevent secondary heavy metal pollution. In this study, we developed an innovative modified steel slag/CaO 2 technology for arsenic recovery and separation via hydrothermal liquefaction (HTL) of As-enriched Pteris vittata L. (PVL). Arsenic migrated from the aqueous phase to the solid phase, with a recovery rate as high as 99.96 %, and the oxidation of arsenite was achieved with an impressive efficiency of 97.64 %. Experiments with model compounds revealed that the As in the PVL was immobilized by metal oxides (CaO, MgO, Fe 2 O 3 and SiO 2 ) in the modified steel slag and deposited in the solid phase. The coprecipitation of arsenic and heavy metals was verified via Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD). As(III) was converted into As(V) via the strong oxidability of •OH and H 2 O 2 from CaO 2 . XPS confirmed that the interconversion of Fe 3+ and Fe 2+ significantly contributed to the oxidation and removal of arsenic. The concentration of As(III) in the system decreased to 1.96 % with this method. To investigate heavy metal recovery from the solid phase, magnetic experiments were subsequently conducted to investigate the arsenic distribution in the solid phase after magnetic separation. Notably, the As could be recovered in the magnetic solid phase, whereas 0.05 % of the As(III) and 18.46 % of the As(V) of the total arsenic were distributed in the non-magnetic solid phase. This study demonstrated that modified steel slag/CaO 2 has great potential for the detoxification and recovery of heavy metals in hyperaccumulators.
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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重金属修复
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废弃物管理
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DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Fei Chai,Samuel Kolog Badazabra,Feiping Zhao,Xu Yan,Qingwei Wang,Xiaobo Min,Liyuan Chai
Arsenic is a widely acknowledged environmental pollutant commonly found in both natural and industrial water systems, posing critical risks to both ecosystems and human health. This study introduces an iron-modified MnMg layered double hydroxide (FeMnMg-LDH) engineered to enhance arsenic removal efficiency for both As(III) and As(V) under environmentally relevant conditions. The materials were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR). The incorporation of Fe into MnMg-LDH led to increased surface area, optimized surface chemistry, and mitigated particle aggregation, thereby exposing additional active sites. The FeMnMg-LDH demonstrated remarkable adsorption capacities of 106.67 mg g −1 for As(III) and 107.63 mg g −1 for As(V), representing a sixfold and twofold enhancement, respectively, over the pristine MnMg-LDH. Adsorption kinetics and isotherms aligned closely with pseudo-second-order and Langmuir models, indicating monolayer chemisorption. Competitive anion experiments revealed minimal interference except for PO 4 3- , underscoring the material’s selectivity. The FeMnMg-LDH retained > 80 % of its initial capacity after three regeneration cycles, demonstrating robust reusability. The mechanisms investigation reveals a synergistic oxidation-adsorption process, where Fe/Mn redox couples facilitated As(III) oxidation to more adsorbable As(V), coupled with immobilization via coprecipitation, surface complexation, electrostatic interactions, and ion exchange. These findings reveal that FeMnMg-LDH is a promising sorbent for arsenic-contained wastewater treatment, offering practical advantages in stability, efficiency, and scalability.
研究领域:
环境科学
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材料科学
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水处理技术
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化学工程
·
分析化学
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高影响因子
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