ENVIRONMENTAL RESEARCH
·
2021
·
IF 6.498
Xiaoqing Meng,Xiaomeng Wang,Chunmei Zhang,Su Yan,Guanyu Zheng,Lixiang Zhou
Co-contamination of arsenic and polycyclic aromatic hydrocarbons (PAHs) in groundwater is frequently reported, and it is thus necessary to develop efficient techniques to tackle this problem. Here, we evaluated the feasibility of utilizing schwertmannite to co-adsorb As(III) and phenanthrene from water solution and regenerating spent schwertmannite via a heterogeneous Fenton-like reaction to degrade adsorbed phenanthrene and meanwhile oxidize adsorbed As(III). The results suggested that schwertmannite with a hedgehog-like morphology was superior to that with a smooth surface for the adsorption removal of As(III) or phenanthrene because of the much higher BET surface area and hydroxyl proportion of the former one, and schwertmannite formed at 72 h incubation effectively co-adsorbed As(III) and phenanthrene from water solution. The adsorption of As(III) and phenanthrene on schwertmannite did not interfere with each other, while the acidic initial solution pH delayed the adsorption of As(III) on schwertmannite but enhanced the adsorption capacity for phenanthrene. The adsorption of As(III) on schwertmannite mainly involved its exchange with SO 4 2− (outer-sphere or inner-sphere) and its complexation with iron hydroxyl surface groups, and phenanthrene adsorption mainly occurred through cation-π bonding and OH-π interaction. During the adsorption-regeneration processes, schwertmannite adsorbed As(III) and phenanthrene firstly, and then it can be successfully regenerated via Fenton-like reaction catalyzed by itself to effectively degrade the adsorbed phenanthrene and meanwhile oxidize the adsorbed As(III) to As(V). Therefore, schwertmanite is an outstanding environmental adsorbent to decontaminate As(III) and phenanthrene co-existing in groundwater.
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
·
2018
·
IF 4.358
Jian Zhang,Wei Li,Ying Li,Lixiang Zhou,Yeqing Lan
Schwertmannite (SCH) has strong adsorption ability to As(III). However, there are few reports on the stability of SCH load with As(III) (SCH-As(III)). In this study, the effects of tartaric acid (TA), pH and coexisting ions including K + , Ca 2+ , Al 3+ and CO 3 2− on the photoreductive dissolution of SCH- As(III) and the release of the adsorbed As (III) were investigated. The results showed that under UV irradiation TA could greatly enhance the release of total Fe and total As from SCH-As(III). Nevertheless, the total Fe and total As in the solution decreased when TA was consumed up. Compared to SCH, the reductive dissolution of SCH-As(III) was obviously suppressed. In the dark, TA could slowly enhance the dissolution of SCH-As(III), but its effect on the release of adsorbed As(III) was weak. Low pH was conducive to the release of iron and arsenic. Ca 2+ , K + , and CO 3 2− promoted the decrease of the dissolved total Fe in the later reaction. However, Al 3+ inhibited the decrease of the dissolved total Fe and total As. The analyses of FTIR and XRD demonstrated that the mineralogical phase of SCH-As(III) after reaction changed. With light, the dissolved total Fe and total As existed mainly as Fe(II) and As(V), respectively. This is because Fe(II) was generated via ligand to metal charge transfer and As(III) was oxidized to As(V) by ·OH produced during the reaction. Thus, this study provides us with a comprehensive understanding of the stability of SCH-As(III) and the release of adsorbed As(III) in natural environments.
研究领域:
环境科学
·
矿物学
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Ting Li,Xiaomeng Wang,Yanmei Chen,Jianru Liang,Lixiang Zhou
Heterogeneous Fenton has become a promising economical and environmentally-friendly method for water treatment, however, the production of abundant radical resources (e.g., O 2 − , OH) are oftentimes limited by finite Fe 2+ species to activate H 2 O 2 . Therefore, development of a new iron-bearing solid modified with diverse functional groups for generating a large of radicals in heterogeneous Fenton is significance. Here, we constructed a Fe 3 O 4 -modified schwertmannite (Fe 3 O 4 /Sch) catalyst to activate H 2 O 2 , SO 4 2− and O 2 to produce three kinds of radicals in heterogeneous Fenton reaction. Specifically, Fe 3 O 4 /Sch catalyst was synthesized to improve its surface properties such as the contents of surface Fe 2+ species as H 2 O 2 or O 2 activators to produce OH or O 2 − , the SO 4 2− of Sch surface as SO 4 − precursor, and electron transfer between Fe 3+ and Fe 2+ . Degradation rate of ciprofloxacin (CIP) for 6 min was up to 97% in Fe 3 O 4 /Sch-H 2 O 2 system, which was higher than that in Sch-H 2 O 2 or Fe 3 O 4 -H 2 O 2 . After four successive cyclic experiments, degradation rate of CIP was still achieved 97% within 10 min in Fe 3 O 4 /Sch-H 2 O 2 system. The formation pathways of the relevant active radicals and the degradation pathways of CIP were also proposed by theoretically calculated and LC-MS data. This finding has not only developed an efficient heterogeneous Fenton catalyst, but also given a new idea of SO 4 − generation by modified iron oxyhydroxysulfate mineral for application of heterogeneous Fenton technology.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
Royal Society Open Science
·
2020
·Vol. 7
·期 7
·
IF 2.646
Dianzhan Wang,Ye Gu,Zhaoshun Yang,Lixiang Zhou
Schwertmannite (sch), an iron oxyhydrosulfate mineral, can catalyse a Fenton-like reaction to degrade organic contaminants, but the reduction of Fe(III) to Fe(II) on the surface of schwertmannite is a limiting step for the Fenton-like process. In the present study, the sch/few-layer graphene (sch–FLG) composite was synthesized to promote the catalytic activity of sch in a Fenton-like reaction. It was found that sch can be successfully carried by FLG in sch–FLG composite, mainly via the chemical bond of Fe–O–C on the surface of sch–FLG. The sch–FLG exhibited a much higher catalytic activity than sch or FLG for the degradation of sulfamethazine (SMT) in the heterogeneous Fenton-like reaction, which resulted from the fact that the FLG can pass electrons efficiently. The degradation efficiency of SMT was around 100% under the reaction conditions of H2O2 200–500 mg l−1, sch–FLG dosage 1–2 g l−1, temperature 28–38°C, and initial solution pH 1–9. During the repeated uses of sch–FLG in the Fenton-like reaction, it maintained a certain catalytic activity for the degradation of SMT and the mineral structure was not changed. In addition, SMT may be finally mineralized in the Fenton-like reaction catalysed by sch–FLG, and the possible degradation pathways were proposed. Therefore, the sch–FLG is an excellent catalyst for SMT degradation in a heterogeneous Fenton-like reaction.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
INORGANIC CHEMISTRY
·
2019
·
IF 4.85
Wei Wang,Mehran Amiri,Tao Huang,Lev N. Zakharov,Yining Zhang,May Nyman
Isolating Fe(III) clusters from water without stabilizing ligands is significantly challenged by the high acidity of Fe3+-bound water, leading to uncontrolled precipitation of iron oxyhydroxides. Here we demonstrate a freeze-drying solvent-exchange method that enabled the isolation of a metastable Fe(III) sulfate decameric cluster formulated [Fe10O2(SO4)12(OCH3)2]·14CH3OH (Fe10). Without stabilization by solvent-exchange, the aqueous species undergoes rapid conversion to the iron sulfate mineral schwertmannite. Monitoring the hydrolysis process from cluster intermediates to schertmannite by small-angle X-ray scattering, we observe the progression from Fe10 to 37 Å soluble nanoparticles prior to the precipitation process. This condensation behavior of Fe10 is further exploited to develop a simple laboratory synthesis of schwetmannite. In addition, we demonstrate the versatility of the freeze-drying solvent-exchange method by isolating Al(III), Zn(II), and Cd(II) substituted Fe(III) sulfate clusters. The freeze-drying solvent-exchange method provides a unique opportunity to isolate cluster intermediates and models to aid in our understanding of metal-ion hydrolysis processes in environmental, material science, and geological studies.
研究领域:
环境科学
·
材料科学
·
地质学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
WATER RESEARCH
·
2025
·
IF 12.4
Yang Wang,Ziyuan Huang,Zhang Yan,Zhenchao Lei,Huanxin Ma,Chunhua Feng
Acid mine drainage (AMD) is characterized by high concentrations of Fe(II) and Fe(III), which can be harnessed for the in-situ formation of schwertmannite, enabling the efficient immobilization of toxic heavy metals. However, existing biological and chemical methods for schwertmannite synthesis face significant challenges, including low Fe(II) oxidation rates and particularly limited Fe(III) precipitation efficiency in acidic environments. In this study, we develop a visible light-assisted photo-electrochemical (PEC) system that effectively overcomes these barriers. By leveraging anodically evolved O 2 and cathodically generated OH − , we achieved facile Fe(II) oxidation at pH 3.0, and an impressive Fe(III) precipitation efficiency of 82.8 %, significantly exceeding the < 30 % efficiency reported by other methods. Mössbauer spectroscopy and X-ray diffraction confirmed that the generated minerals are high-purity schwertmannite. Experimental and theoretical analyses revealed that in the presence of cathodic alkalinity, Fe(III) undergoes further hydrolysis to form [(H₂O) 3 Fe(OH) 2 (SO 4 )] − species, which are thermodynamically capable of spontaneous polymerization and mineralization. Furthermore, the photoreduction of [(H₂O) 4 Fe(SO 4 ) 2 ] − within the PEC system, followed by subsequent oxidation, plays a crucial role in facilitating Fe(III) mineralization. The PEC system also effectively transformed As(III) to As(V) and Cr(VI) to Cr(III) in AMD, promoting their immobilization in the resultant schwertmannite.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Sciences
·
2019
·
IF 3.556
Xianyou Su,Xufang Li,Luming Ma,Jinhong Fan
The massive amount of sludge generated by the classic Fenton process, which has often been hypothesized to consist of ferric hydroxide, remains a major obstacle to its large-scale application. Therefore, reutilization of Fenton sludge has recently gained more attention. Understanding the formation, transformation, and properties of Fenton sludge combined with the stages of the Fenton reaction is pivotal, but not well illustrated yet. In this study, SEM-EDS, FT-IR, XRD, and XPS were applied to study the morphology, crystallinity , elemental composition, and valence state of Fenton sludge. The authors report that schwertmannite and 2-line ferrihydrite were generated and transformed in the oxidation phase and the neutralization phase of the Fenton process. SO 4 2− in the solution decreased by 8.7%–26.0% at different molar ratios of Fe(II) to H 2 O 2 ; meanwhile, iron ion precipitated completely at pH 3.70 with the formation of schwertmannite containing sulfate groups in the Fenton sludge. The structural sulfate (Fe-SO 4 ) in schwertmannite was released from the precipitate with the addition of OH − , and the production of Fenton sludge decreased with increasing pH when pH > 3.70. Goethite was found to form when the final pH was adjusted to 12 or at a reaction temperature of 80°C. Moreover, the possible thermal transformation to goethite and hematite indicated that Fenton sludge can be reused as a raw material for synthesizing more stable iron (hydro)oxides. The results provide useful insights into the formation and transformation of Fenton sludge, with implications for regulating the crystal type of Fenton sludge for further reuse.
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2021
·
IF 7.963
Yunling Zhang,Kun Gao,Zhi Dang,Weilin Huang,John R. Reinfelder,Yuan Ren
Arsenic–rich schwertmannite may cause arsenic (As) release during phase transition. In this study, microbial sulfidogenesis on As(V)–loaded schwertmannite (As-Sch) and associated As mobility at different SO 4 2− concentrations were investigated under anaerobic conditions by Desulfosporosinus meridiei ( D. meridiei ). For biotic treatments, the more SO 4 2− was added, the more Fe 3+ was reduced to Fe 2+ , and the more As(V) was released during the reductive dissolution of As-Sch. The reduction of As(V) to As(III) by D. meridiei resulted in a higher concentration, toxicity, solubility and mobility of As than the corresponding abiotic treatments. However, compared with the abiotic treatments, a variety of new minerals (such as mackinawite , vivianite , sulfur, As 2 S 3 , and parasymplesite) were generated in the biotic treatments, and the As concentration in aqueous solution was less than 1 μM at the end of the incubation period regardless of the presence of SO 4 2− . The results of continuous extraction of different species of As from secondary minerals showed that the effect of microorganisms decreased As content of amorphous iron oxide-bound phase, while increasing that bound on the surface of iron oxide surface-bound phase, thus increasing As fluidity. Our findings indicated that under anaerobic conditions, D. meridiei sulfidogenesis can trigger significant As mobilization in the early stage and remove As from the aqueous solutions when new minerals are formed at a later stage.
研究领域:
环境科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Coatings
·
2023
·Vol. 13
·期 6
·1097
·
IF 3.4
Xiaoqing Meng,Lin Wang,Ying Yang,Yuqi Song,Cansheng Yuan
Sulfamethoxazole (SMX) contamination in large quantities of wastewater can cause potential environmental problems. Due to difficulty in degrading SMX by natural processes, it is necessary to develop a novel technology to solve this problem. Advanced oxidation processes (AOPs) have been identified as methods with a high potential to treat recalcitrant organic pollutants. The nanoscale schwertmannite (nano-SWT) was prepared with an indoor-temperature synthesis method facilitated by polyvinylpyrrolidone (PVP). In this study, we performed a reaction of the nano-SWT materials with Fenton-like catalysts for SMX degradation in hydrogen peroxide (H2O2) media. The findings showed that the nano-SWT prepared by addition of 0.1 g·L−1PVP (nano-SWT-n,n= 0.1) could degrade 92.5% of the SMX within 90 min at indoor temperature, which was due to the nano-SWT providing abundant reaction sites at the solid/solution interfaces. Additionally, SMX could be highly mineralized with 75% TOC removal and H2O2was efficiently utilized during the nano-SWT/H2O2process. In addition, after six cycles of Fenton-like degradation, the nano-SWT remained stable and reusable as a Fenton-like catalyst for SMX degradation. The nano-SWT performed well as a catalyst for SMX degradation. Additionally, this work provides a feasible environmental purification approach for the efficient degradation of SMX through the use of nanoscale schwertmannite as a catalyst in heterogeneous Fenton-like systems.Keywords:Fenton-like;sulfamethoxazole;nanoscale schwertmannite;degradation
研究领域:
环境科学
·
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Xuebin Zhang,Yule Wang,Songhai Wu,Xingjian Dai,Yuxin Zhang,Li Feng,Xu Han
Schwertmannite (Sch) has been proved to be a promising and efficient adsorbent for the removal of various metal ions . However, how to further improve the adsorption capacity and stability of Sch to As(III), As(V) and P(V) is always a problem. In this study, we developed a method to synthesize various Schs with different initial ratios of SO 4 2- :Fe(III). Our results show that Schs can be used to remove As(III), As(V) and P(V) in a wide concentration range of pH 3.0–7.0, and negligible difference can be observed in the adsorption capacities of various Schs towards As(III), As(V) and P(V), indicating that increasing initial concentrations of SO 4 2- does not necessarily increase the adsorption capacity of Sch. In addition, the maximum adsorption capacities ( Q max ) of Sch-0.75 towards As(V) and P(V) increases with decreasing pHs, whereas increase with increasing pHs towards As(III). The Q max values of As(III), As(V) and P(V) are 80.5, 161.5 and 139.9 mg g −1 at pH 3.0, respectively, and are 214.5, 107.6 and 86.5 mg g −1 at pH 7.0, respectively, indicating that the strong dependence of Q max on pH values. Besides, we also successfully developed a method to synthesize the diatomite-modified Sch (DMS). The synthesized DMS with the ratio of Fe(III) salts and diatomite of 4:1 (DMS-4) shows the maximum adsorption capacities of As(III), As(V) and P(V) of 59.81, 151.52 and 236.97 mg g −1 at pH 3.0, respectively, and of 282.49, 126.58 and 165.02 mg g −1 at pH 7.0, respectively. DMS-4 also shows high stability during repeated experiments, and the removal efficiencies of DMS-4 to As(III), As(V) and P(V) maintain 97.42 %, 88.39 % and 94.72 % after five cycles, whereas the removal efficiencies of Sch-0.75 rapidly decrease to 63.61 %, 31.12 % and 50.71 % towards As(III), As(V) and P(V) after five cycles. This study provides a new method to synthesize stable DMS with high adsorption capacities towards As(III), As(V) and P(V).
研究领域:
环境科学
·
水处理技术
·
吸附材料
·
环境化学
·
污染控制
✓ 已验证
DOI
高影响因子
CHEMICAL GEOLOGY
·
2019
·
IF 3.618
Yingying Xie,Xiaoyun Yi,Kinjal J. Shah,John R. Reinfelder,Han Ye,Pen-Chi Chiang,Zhenqing Shi,Zhi Dang,Guining Lu
Schwertmannite is a ferric oxyhydroxy-sulfate mineral, which is commonly found in acid sulfate systems. In this study, the liberation of chromium from Cr(VI)-substituted schwertmannite in the presence of the siderophore desferrioxamine B was studied. In addition, mineral transformation was examined using X-ray diffraction, scanning electron microscopy, and X-ray absorption spectroscopy. Based on solid phase analyses, the transformation of schwertmannite incubated at pH 6.5 in the presence of 100 mg/L desferrioxamine B proceeded through a ligand-reductive induced pathway that released dissolved sulfate, Fe(III), and Cr(III), and generated goethite . Results of XAFS showed that CrO 4 2− substituted for SO 4 2− in the schwertmannite framework. Kinetic analysis using the Kabai and shrinking core models showed that Cr suppressed the transformation of schwertmannite into goethite and the liberation of Cr was controlled by diffusion through the secondary mineral's layer of dissolution. The information provided in this study will be useful in predicting the effects of the interaction between dissolved organic matter and minerals on the mobilization of Cr in acid mine drainage systems.
研究领域:
环境科学
·
矿物学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2018
·Vol. 25
·期 16
·15492-15506
·
IF 2.8
Li Junfei,Xie Yingying,Lu Guining,Ye Han,Yi Xiaoyun,Reinfelder John R.,Lin Zhang,Dang Zhi
Schwertmannite, a Fe(III)-oxyhydroxysulfate mineral formed in acidic (pH 3~4), iron- and sulfate-rich acid mine drainage (AMD) environments, tends to undergo phase transformations with changes in pH and redox condition, which may depend on the presence of various trace anions and cations. In the present study, the effects of Cu(II) on the stability of arsenate-, chromate-, and molybdate-substituted schwertmannite were investigated. The release of Fe(III) and sulfate from schwertmannite seems to be accelerated in the presence of Cu(II) at pH ~ 3, while Cu(II) retarded the dissolution of schwertmannite at pH ~ 5. XRD and SEM results showed that pure schwertmannite and chromate-substituted schwertmannite underwent transformation to goethite over a 2-month period, the presence of Cu(II) enhanced the stability of the mineral’s structure at both pH 3 and 5. However, the structures of arsenate- and molybdate-substituted schwertmannites showed no significant changes in the presence or absence of Cu(II) at both pH 3 and 5. During the phase transformation process, the amount of released oxyanions followed the sequence of chromate > molybdate > arsenate. Moreover, the release of arsenate and chromate from schwertmannite was retarded in the presence of Cu(II) at pH 5, whereas the release of molybdate was promoted. These results have important environmental implications for the stability of schwertmannite and its potential to immobilize contaminant trace elements under AMD conditions.
研究领域:
环境科学
·
矿物学
✓ 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）