SEPARATION AND PURIFICATION TECHNOLOGY
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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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产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2024
·
IF 10.8
Yibing Xie,Xueqian Wang,Zan Qu,Ping Ning,Langlang Wang,Haomiao Xu,Wenjun Huang,Jichang Lu,Jianfei Luo
The transformation of toxic arsine (AsH3) gas into valuable elemental arsenic (As0) from industrial exhaust gases is important for achieving sustainable development goals. Although advanced arsenic removal catalysts can improve the removal efficiency of AsH3, toxic arsenic oxides generated during this process have not received adequate attention. In light of this, a novel approach for obtaining stable As0 products was proposed by performing controlled moderate oxidation. We designed a tailored Ni-based catalyst through an acid etching approach to alter interactions between Ni and NaY. As a result, the 1Ni/NaY-H catalyst yielded an unprecedented proportion of As0 as the major product (65%), which is superior to those of other reported catalysts that only produced arsenic oxides. Density functional theory calculations clarified that Ni species changed the electronic structure of oxygen atoms, and the formed [NiIII–OH (μ-O)] active centers facilitated the adsorption of AsH2*, AsH*, and As* reaction intermediates for As–H bond cleavage, thereby decreasing the direct reactivity of oxygen with the arsenic intermediates. This work presents pioneering insights into inhibiting excessive oxidation during AsH3 removal, demonstrating potential environmental applications for recovery of As0 from toxic AsH3.
研究领域:
环境科学
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催化化学
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材料科学
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Junyu Fan,Zhaoxia Ding,Zhiwei Zhao,Jie Liu
In this study, potassium ferrate(VI) was employed for the degradation of p-arsanilic acid (p-ASA) and simultaneous removal of the generated arsenic species though in-situ coagulation. The effects of several factors, including ferrate(VI) dosage, initial pH, coexisting anions, and humic acid, on the p-ASA degradation and arsenic species removal were investigated. Under various water quality conditions, an excellent removal of p-ASA could always be achieved with the 20:1 mol radio dosage of ferrate(VI) and p-ASA within 30 min. But the removal of arsenic species is significantly affected by the water quality. It could be inhibited by alkalinity and presence of phosphate and humic acid. The generated ferric oxide was mainly 2-line ferrihydrite according to the XRD and XPS analysis. Based on the HPLC-HG-AFS and GC–MS analysis, the major degradation products were detected and the mechanism of the p-ASA degradation by ferrate(VI) and the released arsenic removal by 2-line ferrihydrite generated from ferrate(VI) was given. Two simultaneous degradation pathways of p-ASA were proposed. The p-ASA in solution attacked by ferrate(VI) in solution would lead cleavage of the As–C bond firstly to generate As(III) and p-aminophenol. On the other hand, small amounts of p-ASA initially absorbed on 2-line ferrihydrite would be firstly converted to 4-nitrophenylarsonic acid through the oxidation of –NH 2 to –NO 2 by ferrate(VI), subsequently transformed to As(III) and p-nitrophenol. Combined with the strong oxidizing and the high removal capacity of released arsenic by its generated product, ferrate(VI) have well potential applications for controlling the risk of p-ASA in wastewater.
研究领域:
环境科学
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化学
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DOI
高影响因子
Journal of Chemistry
·
2021
·Vol. 2021
·期 1
·5556295
·
IF 2.506
Zongqiang Zhu,Hongqu Yang,Jie Liu,Yinian Zhu,Shen Tang,Lihao Zhang,Xingxing Wang
Basic ferric sulfate-arsenates [FeSAsOH, Fe(SO 4 ) x (AsO 4 ) y (OH) z ·nH 2 O] were prepared and characterized to study their potential fixation of arsenic in the oxidizing and acidic environment through a dissolution for 330d. The synthetic solids were well-shaped monoclinic prismatic crystals. For the dissolution of the sample FeSAsOH–1 [Fe(SO 4 ) 0.27 (AsO 4 ) 0.73 (OH) 0.27 ·0.26H 2 O] at 25–45°C and initial pH 2, all constituents preferred to be dissolved in the order of AsO 4 3− > SO 4 2− > Fe 3+ in 1–3 h, in the order of SO 4 2− > AsO 4 3− > Fe 3+ from 1–3 h to 12–24 h, and finally in the order of SO 4 2− > Fe 3+ > AsO 4 3− . The released iron, sulfate, and arsenate existed dominantly as Fe 3+ /Fe(OH) 2+ /FeSO 4 + , HSO 4 − /SO 4 2− /FeSO 4 + , and H 3 AsO 4 0 /H 2 AsO 4 − , respectively. The higher initial pHs (6 and 10) could obviously inhibit the release of Fe 3+ from solid into solution, and the solid components were released in the order of SO 4 2− > AsO 4 3− > Fe 3+ . The crystal tops were first dissolved, and the crystal surfaces were gradually smoothed/rounded until all edges and corners disappeared. The dissociations were restricted by the Fe-O(H) breakdown in the FeO 6 octahedra and obstructed by the OH − and AsO 4 tetrahedra outliers; the lowest concentration of the dissolved arsenic was 0.045 mg/L. Based on the dissolution experiment at 25°C and pH 2, the solubility products ( K sp ) for the basic ferric sulfate-arsenate [Fe(SO 4 ) 0.27 (AsO 4 ) 0.73 (OH) 0.27 ·0.26H 2 O], which are equal to the ion activity products (logˍIAP) at equilibrium, were calculated to be -23.04 ± 0.01 with the resulting Gibbs free energies of formation (Δ G f o ) of −914.06 ± 0.03 kJ/mol.
研究领域:
化学
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环境科学
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2016
·
IF 4.836
Anan Wang,Ying Teng,Xuefeng Hu,Longhua Wu,Yujuan Huang,Yongming Luo,Peter Christie
Diphenylarsinic acid (DPAA) is a major contaminant in environments polluted by chemical weapons and abandoned after World Wars I and II and poses high risks to biota but remediation methods for this contaminant are rare. Here, the photodegradtion of DPAA was studied under high-pressure Hg lamp irradiation. DPAA was degraded completely into inorganic arsenic species in 30 min under UV-C irradiation. The photodegradation of DPAA depended mainly on its direct photolysis through excited-state DPAA. By contrast, the generation of 1 O 2 during the photodegradation of DPAA was confirmed by electron paramagnetic resonance (EPR) studies, but 1 O 2 had little effect on the photodegradation of DPAA. Phtotodegradation of DPAA was also studied in soil leachates and groundwater and the photolytic rate of DPAA was controlled by the total organic carbon (TOC) content in soil leachates and by the NO 3 − concentration in groundwater. Finally, studies on the effects of common solutes on the photodegradation of DPAA show that Cl − can increase the photolytic rate of DPAA by prolonging the lifetime of excited-state DPAA. Moreover, NO 3 − , NO 2 − , and humic acid (HA) can decrease the photolytic rate of DPAA by suppressing the production of excited-state DPAA. This research shows the detailed mechanism of DPAA photodegradation and provides a new and effective method for DPAA decontamination.
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
Analytical Methods
·
2025
·
IF 2.6
Huachun Liu,Yanfang Cheng,Hongwei Zhou,Xinhong Pan,Rongfei Peng,Zhijun Bai,Juntao Li,Lei Tan
Arsenic is a widely studied toxic element that exists in various species with different oxidation states and forms in the environment and biological systems. The different physicochemical properties, environmental behaviors, and toxicities of these arsenic species make speciation analysis essential for environmental monitoring and human health risk assessment. In this study, we demonstrated the determination and monitoring of six arsenic species, including arsenite (AsIII), arsenate (AsV), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), arsenocholine (AsC), and arsenobetaine (AsB) in seafood using high-performance liquid chromatography coupled with inductively coupled plasma mass spectrometry (HPLC-ICP-MS). We optimized the chromatographic condition and sample preparation for the separation and extraction of arsenic species, and the method was validated with accuracy and reproducibility using certified reference materials and actual samples. Baseline separation of the arsenic species was achieved within 12 min, and oven heat extraction was selected for sample preparation. The method showed excellent linearity for arsenic species from 0.1 to 100 μg L−1, with recoveries ranging from 92% to 123%, intra-day precision of 0.9–5.0%, and inter-day precision of 1.1–19.4%. The method was further used to determine the arsenic species in 109 mollusks, 195 crustaceans, and 195 marine fish samples from Guangdong, China. Distinctive patterns of arsenic species distribution were observed among different seafood categories. AsB was consistently the predominant species across all samples, with a detection frequency higher than 97.9% and contributed to more than 90% of total arsenic, other arsenic species showed marked variations in their occurrence and concentrations.
研究领域:
分析化学
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环境科学
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食品安全
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毒理学
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产品关联
DOI
PubMed
高影响因子
Scientific Reports
·
2017
·Vol. 7
·期 1
·1-11
·
IF 4.259
Tian Zeyuan,Feng Yong,Guan Yiyi,Shao Binbin,Zhang Yalei,Wu Deli
Freshly prepared carbonate structural Fe(II) (CSF) was used to immobilize As(III) and As(V) in wastewater under oxic and anoxic conditions. Dissolved oxygen was found to exert opposite effects on these two arsenic species. The sorption density of As(III) was higher under oxic conditions, whereas that of As(V) was higher under anoxic conditions. X-ray diffraction and infrared spectroscopic analyses indicated that crystalline parasymplesite (Fe(II) 3 (AsO 4 ) 2 ·8H 2 O) was formed when As(V) was removed under anoxic conditions, while an amorphous Fe-As-containing precipitate was formed when As(III) was removed under oxic conditions. The distribution of arsenic and iron between the solution and sediments suggested that the oxidation of structural Fe(II) promoted coprecipitation process and inhibited surface complexation. X-ray photoelectron spectroscopic analyses revealed that more As(III) was oxidized under oxic condition, which contributed to a higher sorption capacity for As(III). The formation of parasymplesite through surface complexation/precipitation was proposed to be more effective for the removal of As(V) by CSF, while As(III) was more efficiently removed through coprecipitation. Together, the results suggest that CSF may be an effective material for sequestering both As(III) and As(V). In addition, attention should be paid to the dissolved oxygen content when remediating different arsenic species.
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
Frontiers in Chemistry
·
2021
·
IF 5.221
Yan Kang,Liu Liping,Zhao Hongxing,Tian Lei,Xu Zhifeng,Wang Ruixiang
To overcome the problem of arsenic separation and enrichment from an alkaline leaching solution in arsenic-containing dust, a CO32--type tri-n-octylmethyl-ammonium chloride (TOMAC) method for extracting thioarsenite is proposed in this paper. Considering an alkaline leaching solution as the research object, after vulcanization pretreatment, TOMAC transformation and organic phase saturated extraction capacity were measured, and the extraction mechanism was preliminarily studied. First, Cl−-type quaternary ammonium salt was effectively transformed to HCO3--type by treating organic phase with saturated NaHCO3five times. TOMAC was effectively transformed from HCO3- to CO32- type by alkaline washing with 1.0 mol/l NaOH solution; this washing was repeated thrice. Thereafter, the effects of organic phase composition, phase ratio, extraction time, and temperature on the extraction and separation of arsenic were investigated. The results show that under the conditions of 30% CO32--type TOMAC + 15% sec-octanol + 55% sulfonated kerosene, VO/VA = 1/1, and 5 min extraction at room temperature, the single-stage extraction rate of AsIII is 85.2%. The AsIII concentration in raffinate can be reduced to less than 1.33 × 10−3 mol/l by four-stage countercurrent extraction, and the extraction rate of AsIII can exceed 98.4%.
研究领域:
化学工程
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环境科学
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2017
·
IF 6.216
Tianyi Sun,Zhiwei Zhao,Zhijie Liang,Jie Liu,Wenxin Shi,Fuyi Cui
A bifunctional CuO-Fe 3 O 4 material was synthesized and employed for the photocatalytic degradation of p-arsanilic acid (p-ASA) under visible light irradiation and simultaneous removal of the released inorganic arsenic by adsorption from solution. The effects of major factors, including solution pH, bicarbonate ion, halide ion and humic acid , on the p-ASA degradation were investigated. Under various water quality conditions, an excellent removal of p-ASA could always be achieved by the CuO-Fe 3 O 4 photocatalytic process and p-ASA could be completely converted to As(V) within 36 min. Simultaneously, the released As(V) could be adsorbed onto the surface of CuO-Fe 3 O 4 nanoparticles with high efficiency above 95% at initial pH range from 4 to 7. The presence of humic acid significantly weakened the degradation of p-ASA by scavenging OH, and slightly inhibited the As(V) removal. On the basis of the UV–vis, FTIR, XPS analysis and the major degradation products detected, the mechanism of the p-ASA photocatalytic degradation and the released As(V) adsorption by CuO-Fe 3 O 4 nanoparticles was given, and the degradation pathway of p-ASA during the photocatalytic process was also taken into consideration. Combined with the photocatalytic property and the high adsorption capacity of As(V), the synthesized magnetic CuO-Fe 3 O 4 nanoparticles have significant potential applications for controlling the risk of p-ASA in wastewater.
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
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2023
·Vol. 30
·期 19
·54556-54567
·
IF 5.8
Zhang Ge,Yang Huifen,Li Xuan,Zhou Yichen,Guo Song,Zhao Tong
The control of multiple heavy metals (HMs) pollution in solid wastes, especially the co-contamination of As and other heavy metal cations, is of great importance to ecological and environmental health. To address this problem, the preparation and application of multifunctional materials have attracted wide attention. In this work, a novel Ca-Fe-Si-S composite (CFSS) was applied to stabilize As, Zn, Cu, and Cd in acid arsenic slag (ASS). The CFSS exhibited synchronous stabilization ability for As, Zn, Cu, Cd and owned strong acid neutralization capacity. Under simulated field conditions, the acid rain extracted HMs in ASS successfully decreased below the emission standard (GB 3838–2002-IV category in China) after incubated by 5% CFSS for 90 days. Meanwhile, the application of CFSS promoted the transformation of leachable HMs into less accessible forms, which was conductive to the long-term stabilization for HMs. There was competitive relation among the three heavy metal cations, following the stabilization sequence of Cu > Zn > Cd during incubation. And the stabilization mechanisms of HMs by CFSS were proposed as chemical precipitation, surface complexation, and ion/anion exchange. The research will be greatly conducive to the remediation and governance of field multiple HMs contaminated sites.
研究领域:
环境科学
·
材料科学
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产品关联
DOI
PubMed
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
·
2024
·
IF 6.2
Wenjun Xiong,Wei Wei,Man He,Bin Hu,Jun Men,Jiawei Tu,Wei Miao
Biomethylation is an effective means of arsenic detoxification by organisms living in aquatic environments. Ciliated protozoa (including Tetrahymena species) play an important role in the biochemical cycles of aquatic ecosystems and have a potential application in arsenic biotransformation. This study compared arsenic tolerance, accumulation, methylation, and efflux in 11 Tetrahymena species. Nineteen arsenite (As(III)) S -adenosylmethionine (SAM) methyltransferase ( arsM ) genes, of which 12 are new discoveries, were identified, and protein sequences were studied. We then constructed recombinant cell lines based on the Tetrahymena thermophila ( T. thermophila ) wild-type SB210 strain and expressed each of the 19 arsM genes under the control of the metal-responsive the MTT1 promoter. In the presence of Cd 2+ and As(V), expression of the arsM genes in the recombinant cell lines was much higher than in the donor species. Evaluation of the recombinant cell line identified one with ultra-high arsenic methylation enzyme activity, significantly higher arsenic methylation capacity and much faster methylation rate than other reported arsenic methylated organisms, which methylated 89% of arsenic within 6.5 h. It also had an excellent capacity for the arsenic detoxification of lake water containing As(V), 56% of arsenic was methylated at 250 μg/L As(V) in 48 h. This study has made a significant contribution to our knowledge on arsenic metabolism in protozoa and demonstrates the great potential to use Tetrahymena species in the arsenic biotransformation of aquatic environments.
研究领域:
环境生物学
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分子生物学
·
生态学
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产品关联
DOI
PubMed
高影响因子
ELECTROPHORESIS
·
2020
·Vol. 42
·期 6
·719-724
·
IF 3.081
Evgeniya V. Polyakova,Olga V. Shuvaeva,Olga S. Koshcheeva,Yuliya E. Tyutereva,Ivan P. Pozdnyakov
Arsenic aromatic compounds including p-arsanylic acid (pASA) are still widely used in a number of countries as the feed additives in animal breeding resulting in its entering the environment. Under the influence of oxidizing agents or UV radiation, pASA undergoes transformations leading to generation of inorganic arsenic species that are more mobile and toxic than organic ones. On the one hand, an approach based on the treatment of contaminated waters by UV irradiation seems perspective for their detoxification, but the feasibility of this approach depends on the composition of the products forming as a result of photodegradation. In the present work, a CZE was applied for the study of the pASA degradation process during stationary (308 nm) photolysis in the presence of Fe(III)-oxalate complex. A developed assay allowed controlling the parent compounds and also As-containing products of pASA degradation, presented mainly by arsenate and arsenite ions. It was found that the main inorganic derivatives of the pASA photolytic conversions are presented by arsenate and arsenite ions whose ratio depends on the initial amount of pASA and reaction conditions.
研究领域:
环境科学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
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