WATER RESEARCH
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2024
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IF 11.4
Hongmei Tang,Meiqing Chen,Pingxiao Wu,Yihao Li,Tianming Wang,Jiayan Wu,Leiye Sun,Zhongbo Shang
Schwertmannite (Sch) is considered as an effective remover of Chromium (Cr) due to its strong affinity for toxic Cr species. Since the instability of Sch, the environmental fate of Cr deserves attention during the transformation of Sch into a more stable crystalline phase. The ubiquitous manganese(II) (Mn(II)) probably affects the transformation of Sch and thus the environmental fate of Cr. Therefore, this study investigated the impact of Mn(II) on the transformation of Cr-absorbed Sch (Cr-Sch) and the associated behavior of SO 4 2− and Cr. We revealed that the transformation products of Cr-Sch at pH 3.0 and 7.0 were goethite and Sch, respectively. The presence of Mn(II) weakened the crystallinity of the transformation products, and the trend was positively correlated with the concentration of Mn(II). However, Mn(II) changed the transformation products of Cr-Sch from hematite to goethite at pH 10.0. Mn(II) replaced Fe(III) in the mineral structures or formed Mn-O complexes with surface hydroxyl groups (-OH), thereby affecting the transformation pathways of Sch. The presence of Mn(II) enhanced the immobilization of Cr on minerals at pH 3.0 and 7.0. Sch is likely to provide an channel for electron transfer between Mn(II) and Cr(VI), which promotes the reduction of Cr(VI). Meanwhile, Mn(Ⅱ) induced more -OH production on the surface of secondary minerals, which played an important role in increasing the Cr fixation. In addition, part of the Mn(Ⅱ) was oxidized to Mn(Ⅲ)/Mn(Ⅳ) at pH 3.0 and pH 7.0. This study helps to predict the role of Mn(II) in the transformations of Cr-Sch in environments and design remediation strategies for Cr contamination.
研究领域:
环境科学
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矿物学
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DOI
PubMed
高影响因子
International Journal of Environmental Science and Technology
·
2023
·Vol. 20
·期 12
·13399-13410
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IF 3.1
Xiong H.,Peng S.,Zhang B.
Nonionic surfactants with ideal surface properties and lower ecotoxicities have been highly attended in metal bioleaching and pollutant bio-treatment in environmental science field. In this study, both Acidithiobacillus ferrooxidans HX3 and Tween 80 (or Triton X-100) presence in cultures, bio-production and development of schwertmannite as a potential metal scavenger were investigated. To explore their correlations, the resulting ferric oxyhydroxides under various surfactant levels (lower/optimal/higher ones for Gp I/II/III treatments) were identified by many characterization methods. Result showed that after 48 h of normally bacterial reproduction, surfactant-rich cultures with Tween 80 more than 50 mg/L (25 mg/L for Triton X-100) could only achieve down 80% of ferrous oxidation percent and 10 7 cells/mL of cell numbers, while those with lower surfactant level were ahead 12 h. Culture pH values decreased to about 2.4 (or 2.0) from initially 2.8. All initial ferric oxyhydroxides were only pincushion-schwertmannite spheres. When cells sequentially reproduced within 36 h–48 h, presence of surfactants (except for Triton X-100 at 75 mg/L) could induce schwertmannite-pincushion assembling on developed spherical particles with a little of diamond-jarosite. And then during bacterial stability state (48 h–72 h), the pincushion assemblages on developed schwertmannite-spheres would disappear, following occurrence of more jarosite amount. Obviously, schwertmannite stability and morphological evolvement were affected by type and level of the added surfactants. These results will give a convincing proof for understanding biomineralization principles of iron minerals in natural environments with nonionic surfactants.
研究领域:
环境科学
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微生物学
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材料科学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Xuqian Wang,Linli Dai,Siyu He,Yabo Wang,Yongkui Zhang
Iron-based heterogeneous catalysts exhibit great peroxymonosulfate (PMS) activation ability to degrade persistent antibiotic pollutants, but the catalytic efficiency of this process is significantly affected by Fe(III)/Fe(II) conversion rate. Herein, we designed a novel biomineralization regulation process to fabricate graphene oxide modified schwertmannite composites (Sch-GO x ) as light-assisted PMS activator for enhancing sulfathiazole (STZ) degradation. More specifically, the introduction of GO in biomineralization process not only facilitated the dispersion of Sch, but also accelerated the regeneration of available surface-bound Fe(II) in resultant Sch-GO x through intramolecular electron transfer, thus promoting the activation of PMS. Compared with biosynthesized Sch without modification, the prepared Sch-GO 100 sample exhibited superior catalytic activity in light-assisted PMS activation process, 99.90 % removal efficiency of 78 μM STZ has been achieved within 30 min without pH adjustment (initial pH = 7.20). Abundant reactive oxygen species including SO 4 − , OH, O 2 − and 1 O 2 were responsible for the effective elimination of STZ. The potential degradation intermediates of STZ were investigated by liquid chromatography-mass spectrometry (LC-MS) and demonstrated to be less toxic than STZ using the ecological structure activity relationship program (ECOSAR). This study provided a facile and environmental-benign strategy of biomineralization regulation to fabricate effective iron-based PMS activator for environmental remediation.
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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DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
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2022
·Vol. 29
·期 51
·77344-77358
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IF 5.19
Ding Baoting,Wang Xiaomeng,Feng Kun,Fu Jingran,Liang Jianru,Zhou Lixiang
Acidic Cr(VI)-containing wastewater has received increasing attention in recent years. Schwertmannite is a suitable adsorbent for its acid resistance and good adsorption ability. However, it shows poor Cr(VI) adsorption performance under acidic conditions. Herein, inspired by the fast neutralization-mineralization process of acid mine drainage (AMD) triggered by alkaline rocks, a novel nano-scaled schwertmannite (Sch-2.7) with high Cr(VI) adsorption capacity was synthesized at constant pH of 2.7 via adding OH − . Compared with common schwertmannite (Sch), appropriate OH − effectively improved mineral yield (the precipitation efficiency of Fe: 96.75% vs. 29.93%), specific surface area (65.1 m 2 /g vs. 18.9 m 2 /g), surface group content, and further Cr(VI) adsorption ability of Sch-2.7. The maximum adsorption capacity was 54.17 (pH = 3), 61.59 (pH = 4), and 66.5 mg/g (pH = 5) for Sch-2.7, whereas only 20.35, 24.51, and 27.17 mg/g for Sch. On average, the former was 2.53 times higher than the latter. Temperature and coexisting ions had little influences on the sorption process of Sch-2.7. The mechanism analysis demonstrated that the Cr(VI) removal by Sch-2.7 was a more thermodynamic favorable process due to abundant reactive-active components on Sch-2.7 for adsorption reaction. This work provided new insight into performance optimization and application potential on Cr(VI) removal of schwertmannite.
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
ACS ES&T Water
·
2025
·
IF 4.3
Ting Li,Xiqing Wang,Xin Du,Murong Wang,Jianru Liang,Lixiang Zhou
The widespread application of Fe-based heterogeneous Fenton in water treatment is hindered by two main challenges: the inefficiency of the Fe(III)/Fe(II) redox cycle and the requirement of acidic conditions. In this study, combining schwertmannite with iron phosphide (Sch/FeP) via pre-adding FeP in the formation process of Sch could enhance the Fe(II)/Fe(III) conversion and self-producing acidic environment by SO42– substitution. Specifically, the inclusion of FeP in the Sch/FeP composite markedly increased the content of ≡Fe(II) species, thereby improving the activation of H2O2 to produce substantial quantities of •OH and •O2– radicals. Sch/FeP-driven heterogeneous Fenton exhibited high total organic carbon (TOC) removal (∼60%) and utilization efficiency of H2O2 (100%) after 20 min. Furthermore, Sch/FeP exhibited excellent degradation performance across a broad pH range (2–10), which could be attributed to the SO42– substitution reaction. This study not only addresses critical challenges in heterogeneous Fenton processes but also provides a novel strategy for modifying sulfate minerals to enhance their environmental applicability.
研究领域:
环境化学
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催化
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水处理
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材料科学
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高级氧化工艺
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2023
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IF 13.6
Ziyuan Huang,Huanxin Ma,Chengshuai Liu,Fangyuan Meng,Jyh-Fu Lee,Yu-Jung Lin,Xiaoyun Yi,Zhi Dang,Chunhua Feng
The increasing need for sustainable acid mine drainage (AMD) treatment has spurred much attention to strategic development of resource recovery. Along this line, we envisage that a coupled electrochemical system involving anodic Fe(II) oxidation and cathodic alkaline production will facilitate in situ synthesis of schwertmannite from AMD. Multiple physicochemical studies showed the successful formation of electrochemistry-induced schwertmannite, with its surface structure and chemical composition closely related to the applied current. A low current (e.g., 50 mA) led to the formation of schwertmannite having a small specific surface area (SSA) of 122.8 m 2 g −1 and containing small amounts of –OH groups (formula Fe 8 O 8 (OH) 4.49 (SO 4 ) 1.76 ), whereas a large current (e.g., 200 mA) led to schwertmannite high in SSA (169.5 m 2 g −1 ) and amounts of –OH groups (formula Fe 8 O 8 (OH) 5.16 (SO 4 ) 1.42 ). Mechanistic studies revealed that the reactive oxygen species (ROS)-mediated pathway, rather than the direct oxidation pathway, plays a dominant role in accelerating Fe(II) oxidation, especially at high currents. The abundance of •OH in the bulk solution, along with the cathodic production of OH − , were the key to obtaining schwertmannite with desirable properties. It was also found to function as a powerful sorbent in removal of arsenic species from the aqueous phase.
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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水处理
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DOI
PubMed
高影响因子
CHEMICAL GEOLOGY
·
2019
·
IF 3.618
Jian Zhang,Yuxin Li,Wei Li,Lixiang Zhou,Yeqing Lan,Jing Guo
This paper focused on understanding the effect of citric acid (CA) on the reductive dissolution of Schwertmannite loaded with arsenite (SCH-As(III)) under UV irradiation and the release of arsenic (As). Results demonstrated that CA could significantly promote the reductive dissolution of SCH and SCH-As(III) with the assistance of ultraviolet light. Initially, the dissolved total iron (Fe) and As exhibited a rapid increase (0 to 240 min), followed by a quick decline due to the depletion of CA. It was found that the dissolved total Fe and As were present mainly as the species of Fe(II) and As(V), respectively. This can be attributed to the electronic transfer from ligand to metal in the complex of Fe(III)-(CA) n occurring under ultraviolet light, leading to the production of Fe(II) and organic radicals. Moreover, As(V) was further generated via the interaction of As(III) with OH from a series of radical reactions. In the dark, CA could also enhance the total Fe and As released from the SCH-As(III). The lower the initial pH level, the greater the amount of total dissolved Fe and As. The presence of Al 3+ clearly suppressed the reductive dissolution of SCH-As(III) triggered by CA and ultraviolet light. SEM spectra indicated that the mineralogical phases of SCH-As(III) before and after the reaction were discrepant. Thus, this study provides an insight into the stability of SCH-As(III) and the migration of As in the natural environment.
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 HAZARDOUS MATERIALS
·
2021
·
IF 10.588
Yingying Xie,Guining Lu,Xueqin Tao,Zhen Wen,Zhi Dang
A novel collaborative strategy for enhanced removal of Cr(VI) using nano zero valent iron (nZVI) assisted by schwertmannite (Sch) with two synthesis methods was designed. Batch experiments demonstrated that nZVI/Sch-AP (synthesized by abiotic precipitation of Fe 3+ species) exhibited excellent removal performance for Cr(VI) than nZVI/Sch-CO (synthesized by chemical oxidation of Fe 2+ species). The results indicated that the removal efficiencies of Cr(VI) by nZVI/Sch-AP and nZVI/Sch-CO were highly pH-dependent and achieved to be 99.99% and 98.01% under the optimal conditions of 10 mg L −1 Cr(VI) concentration, a pH of 6.3 and a Fe(0)/Cr(VI) molar ratio of 12. But nZVI/Sch-AP emerged greater k of 0.1097 min −1 than that of nZVI/Sch-CO (0.0485 min −1 ). Humic acid exhibited promotion effect on the Cr(VI) removal in low concentration of 1 mg L −1 . Results of XRD and XPS demonstrated that α-FeOOH was the dominant products in both incubations of nZVI/Sch-AP and nZVI/Sch-CO, accompanied with FeCr 2 O 4 and Cr Fe mixed (oxy)hydroxides, and γ-FeOOH was found alone in the incubations of nZVI/Sch-CO. We proposed a consecutive and simultaneous process involving surface absorption-reduction and co-precipitation/immobilization for the removal. This study provides new insights into the elimination of Cr(VI) from wastewater by nZVI/Sch, especially in acid mine drainage .
研究领域:
环境科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2019
·
IF 5.108
Xiaoqing Meng,Chunmei Zhang,Jing Zhuang,Guanyu Zheng,Lixiang Zhou
Schwertmannite , jarosite or goethite are commonly used to remove metals and/or metalloids from contaminated water via adsorption processes, but it is still unclear whether they can be used as adsorbents to remove hydrophobic organic pollutants (HOCs), such as polycyclic aromatic hydrocarbons (PAHs), from groundwater or wastewater. Here, the feasibility of using these iron (oxyhydr) oxide minerals as adsorbents for phenanthrene (a model PAH) adsorption and regenerating the spent adsorbents via heterogeneous Fenton-like reaction was investigated. Results showed that they exhibited rapid adsorption rates and considerable adsorption capacities for phenanthrene. The maximum Langmuir capacities (Qmax) for phenanthrene adsorption at 28 °C were in an ascending order of goethite (567 μg·g-1) < schwertmannite (727 μg·g-1) < jarosite (2088 μg·g-1). The adsorption process was a spontaneous and exothermic process along with the decrease of randomness at the solid/liquid interfaces, which was influenced by temperature, adsorbent dosage, and the coexistence of inorganic anions. Both schwertmannite and jarosite were superior to goethite in light of their easy separation from the bulk solution after the adsorption processes. A multi-cycle experiment demonstrated that the regeneration efficiency of schwertmannite (97.9–99.7%) was much higher than that of jarosite (80.1–87.2%), and the mineral structure, morphology and functional groups of schwertmannite were not changed during the successive adsorption-regeneration processes. Therefore, among the investigated three iron (oxyhydr) oxide minerals, schwertmannite was an attractive and regenerable adsorbent for the removal of phenanthrene from water owing to its high adsorption capacity, good separation ability, and excellent reusability.
研究领域:
环境科学
·
化学工程
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DOI
PubMed
高影响因子
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