CHEMOSPHERE
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2021
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IF 7.086
Fenglei Liu,Shan Hua,Chao Wang,Baowei Hu
Herein, using dialdehyde waste paper (DAWP) as a cross-linking agent to immobilize persimmon tannin (PT) was first used to remove the U(VI) and Cr(VI) via the “waste control by waste” concept. The microscopic and macroscopic surface properties of the as-prepared adsorbent was characterized by the advanced characterization techniques. Factors that affected the elimination process such as variable pH, coexistence ions and equilibrium time were investigated by batch techniques. The results showed that the maximal removal capacities of U(VI) and Cr(VI) on DAWP-PT were 242.3 mg/g (pH = 6.0) and 178.7 mg/g (pH = 2.0) at 298 K, which exhibited competitiveness with most of the reported solid materials. Meanwhile, adsorption data were fitted perfectly to the Langmuir and Pseudo-second-order equations, which indicated that the monolayer and homogenous chemisorption dominated the removal process. The SEM-EDX, DFT and XPS analysis conformed that adsorption of U(VI) was mainly via surface complexation, while the elimination of Cr(VI) was a redox reaction process, and about 65.33% of Cr(III) and 34.67% of Cr(VI) co-existed onto the surface of DAWP-PT. Thus, this study would provide a high-efficiency and low-cost adsorbent for radionuclide and heavy metal treatment.
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
JOURNAL OF HAZARDOUS MATERIALS
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2025
·
IF 11.3
Jian Gao,Yuqi Shi,Minglu Tang,Yuancai Chen
Chromate bioreduction is a promising bioremediation strategy, but its application in wastewater treatment is limited by the Cr(VI) biotoxicity, particularly due to the generation of Cr(VI)-induced reactive oxygen species (ROS). To mitigate these adverse effect, this study synthesized bio-Pd 0 in Citrobacter freundii to modulate distinct Cr(VI) aerobic/anaerobic reduction pathways. With the incorporation of bio-Pd 0 , aerobic and anaerobic Cr(VI) specific removal rate increased by 18.1–21.2 and 51.5–87.9 times, respectively. The genomics, RT-qPCR, respiratory inhibition experiments, ROS levels and antioxidant enzyme activity assays demonstrated that bio-Pd 0 enhanced intracellular Cr(VI) aerobic bioreduction mainly via upregulating the chromate multi-electron reductase (Cr-MER) (related with YieF, NfsA and NemA), together with the energy-dependent resistance system (antioxidant enzyme superoxide dismutase and catalase, efflux pump Emr, DNA repair protein RecG). Cr-MER and resistance system effectively reduced the generation and accumulation of ROS, respectively. For anaerobic conditions, bio-Pd 0 facilitated hydrogenase-mediated short respiratory chain (S-chain) to reduce Cr(VI) extracellularly (related with HypE, RutF and OmcG), avoiding ROS generation and the energy consumption of the intracellular detoxification system, and maximized the energy utilization for Cr(VI) extracellular reduction. This study provides a new strategy for Cr(VI) bioreduction and elucidates the underlying mechanism.
研究领域:
环境生物技术
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微生物学
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生物修复
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生物化学
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基因组学
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毒理学
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产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2025
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IF 3.7
Biao Yuan,Fujin Sun,Pingting Chen,Kunpeng He,Pan Wu,Changjun Liu,Jian He,Wei Jiang
With the development of vanadium redox flow battery technology, the demand for pure vanadium is rapidly increasing. The separation of vanadium from vanadium–chromium leaching solutions are critical step in the production of purity-vanadium. This study presents an innovative adsorption process that utilizes amorphous ZrO 2 (AZrO) for the selective separation of V(V) and Cr(VI). In this process, a high adsorption capacity for V(V) at 64.5 mg·g –1 was achieved, while the capacity for Cr(VI) is relatively low at 24.1 mg·g –1 , demonstrating good separation performance. This is mainly caused by the large specific surface area and mesoporous structure, which are favorable for molecular diffusion and mass transfer. The kinetic analysis shows that the adsorption process follows pseudo-second-order kinetic process with chemisorption being the rate-controlling process. AZrO showed excellent separation performance in mixed solutions over a wide range of concentrations. After five cycles, AZrO retained over 73% of its capacity, indicating good stability. In mixed solutions containing up to 40 g·L –1 of V(V) and 3 g·L –1 of Cr(VI), the innovative adsorption process successfully achieved effective separation and purification. By an adsorption–desorption process using 0.1 mol·L –1 NaOH, a 99.02% V(V)-rich solution was obtained from a high concentration sodium vanadium slag leaching solution, demonstrating its effectiveness for practical industrial applications.
研究领域:
化学工程
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材料科学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2025
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IF 9
Junyi Xiang,Xi Lu,Hongru Rao,Luwei Bai,Qingyun Huang,Xuewei Lv
The separation of vanadium and chromium from vanadium-chromium slag constitutes the greatest bottleneck in the exploitation and utilization of high-chromium vanadium-titanium magnetite, which mainly results from the insufficient understanding of the behavior of similar elements vanadium and chromium during the extraction process. In this research, a series of spinels FeV x Cr 2- x O 4 (0 ≤ x ≤ 2) were synthesized via the high-temperature solid-state method, and their sodium roasting and leaching behavior were comprehensively analyzed. The transformation rules of sodium vanadate and chromate were investigated by XRD, SEM-EDS, FTIR, and thermodynamic calculation. The results indicate that in the FeV x Cr 2- x O 4 (0 ≤ x ≤ 2) − Na 2 CO 3 system, at 300°C, a portion of chromium spinel phase is preferentially and slowly oxidized to Cr 2 O 3 , while the vanadium spinel rapidly oxidizes to form NaVO 3 at 400°C. Above 500°C, NaVO 3 further reacts with Na 2 CO 3 to form Na 4 V 2 O 7 , and Na 2 CrO 4 also begins to form concurrently. As the proportion of Cr in FeV x Cr 2- x O 4 increases, both the leaching efficiencies of vanadium and chromium from the sodium-roasted samples decrease, with the leaching efficiency of chromium decreasing more significantly. Significant competitive and synergistic effects between vanadium and chromium are observed in the roasting of FeV x Cr 2- x O 4 with Na 2 CO 3 . This study is expected to provide theoretical support for the development of efficient vanadium-chromium extraction processes.
研究领域:
冶金学
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材料科学
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2024
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IF 4.9
Mengjie Huang,Mengjia Zhang,Xinyu Huan,Yuanyi Li,Wei Wei,Yong Zhang
Microplastics (MPs) commonly undergo aging in various environmental media, affecting both their environmental behavior and Trojan-horse effect for contaminants. However, the mechanisms underlying the different impact of various aging processes on the Trojan-horse effect of polyamide (PA) MPs towards metal oxyanions remain unclear. This study explored how chemical aging and UV irradiation impact the structural characteristics and Cr(VI) adsorption of PA MPs under various influencing factors. Results showed that both aging processes enhanced the negative surface charge, surface oxygen content, and roughness of PA MPs, with FTIR correlation spectroscopy confirming an increase in O-containing functional groups. Cr(VI) adsorption onto aged PA sharply increased by 17.4 % (14 days of UV irradiation), 39.4 % (42 days of UV irradiation), and 21.7 % (chemical aging) compared to original PA. Salinity and natural organic matter had adverse effects on Cr(VI) adsorption. Spectroscopic analyses highlighted the crucial role of hydrophilic amide groups in controlling Cr(VI) adsorption onto aged PA, involving hydrogen bonding, electrostatic interactions, and reduction. Aged PA exhibited higher adsorption capacities but also greater desorption under simulated seawater and intestinal fluid, suggesting increased migration potential for Cr(VI). This study provides helpful insights into assessing the environmental risk of co-existing PA MPs and metal oxyanions, particularly considering the effect of aging processes.
研究领域:
环境科学
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化学
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产品关联
DOI
高影响因子
WATER AIR AND SOIL POLLUTION
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2020
·Vol. 231
·期 2
·1-12
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IF 1.9
Zeng Ganning,Hong Chunxian,Zhang Yan,You Hanzhang,Shi Wenyue,Du Mingming,Ai Ning,Chen Bing
A novel polymer/activated carbon composite was prepared in this study by one-step chemical activation of Sargassum horneri , followed by surface modification with chitosan, a widely abundant biopolymer. The prepared composite was used as adsorbent to remove one of the most toxic metal ions, Cr(VI), from aqueous solution. Surface characterization tests revealed the material to be predominantly mesoporous with the specific surface area of 293.4 m 2 ·g −1 and the average pore diameter of 6.27 nm. Enhanced uptake capacity of Cr(VI) by the prepared composite was obtained due to the presence of more metal-binding functional (amino and hydroxyl) groups on its surface. Extremely fast adsorption rate of Cr(VI) was also achieved due to the porous structure of the prepared composite. This study has clearly shown that Sargassum horneri can be a potential alternative precursor for carbon-based adsorbents and the proper designed polymer/AC composites can be tailor-made adsorbents for heavy metal removal.
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
Surfaces and Interfaces
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2024
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IF 5.7
Fen Zhang,Shuyu He,Luyao Xi,Liying Ma,Liwen Zhang,Ling Xiong,Shaohua Chen,Benjun Xi
Reduction of Cr(VI) to Cr(III) or elimination of Cr(VI) from aqueous environments is the most commonly used method to address Cr(VI) contamination. Waste molasses (WM) is a by-product from the sugar industry, if discharged arbitrarily without treatment can lead to waste of resources and cause serious environmental pollution . In this study, the modification of polypyrrole (PPy) with WM (PPy/WM) not only provided PPy with good dispersibility and higher specific surface area, but it can also enrich the functional groups on the surface of PPy. The findings indicated that PPy/WM composites can serve as superior adsorbent materials for highly efficient and selective removal of Cr(VI) when different interfering ions are present. e.g., 150 mg/L of Cr(VI) can be eliminated completely within 6 h under the condition of PPy/WM amount of 0.8 g/L, temperature of 303 K, and pH of 2.0. PPy/WM showed excellent performance for removal of Cr(VI) in a wide pH range (2.0 - 10.0). PPy/WM exhibited excellent reusability for five cycles without obvious loss of its adsorption capacity. The maximum Cr(VI) adsorption capacity of PPy/WM was 662.25 mg/g at 323 K, evidently higher than that of unmodified PPy (194.17 mg/g). Cr(VI) removal by PPy/WM was chiefly accomplished by electrostatic adsorption, ion exchange and in-site reduction. This study not only provides a new technology for efficient adsorption and in-situ reduction of Cr(VI), but also realizes the resource utilization of WM and solves the WM pollution problems.
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
Toxics
·
2025
·Vol. 13
·期 6
·458
·
IF 4.1
Hang Liu,Runlin Yao,Mingling Yu,Zongda Ye,Yingrui Lu,Xiaolong Yu,Jin Tang,Jianteng Sun
Hexavalent chromium (Cr(VI)) is of significant interest in the environmental field due to its high toxicity. Biochar is commonly used as an adsorbent for Cr(VI) removal from wastewater. However, its lower removal efficiency remains a persistent challenge. This study develops an iron-modified rice straw biochar through a simple precipitation and pyrolysis method and applies it for Cr(VI) removal in wastewater, which could convert waste into treasure and improve the adsorption performance of adsorbent. In the adsorption experiments, the results revealed that the adsorption efficiency of Cr(VI) reached 95.54% within 480 min (conditions: adsorbent dosage 2.67 g/L, pH 2.5, temperature 25 ± 2 °C). The Langmuir isotherm model was more suitable to describe the adsorption behavior of Cr(VI) by Fe-BC, and the fitted adsorption capacity achieved 10.03 mg/g. The experimental process was better described by the pseudo-second-order kinetic model, indicating that the adsorption process chemical adsorption was the rate-limiting step. The thermodynamic experiments revealed that the adsorption process of Cr(VI) by Fe-BC was spontaneous and endothermic. Column experiments demonstrated that a lower flow speed was beneficial to adsorption performance. Mechanistic studies highlighted the synergistic roles of electrostatic attraction, ion exchange, and reduction in Cr(VI) removal. These findings provide novel perspectives and innovative approaches for the development and application of adsorbents.
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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产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Weiduo Zhao,Zhongwei Zhao,Yingpeng Xu,Ziming Cao,Tianyu Zhao
High-chromium vanadium slag, a typical hazardous solid waste, serves as a critical raw material for the comprehensive utilization of vanadium and chromium resources. To achieve synergistic recovery of vanadium and chromium, this study proposes an innovative process based on mineral phase reconstruction. A ternary eutectic multi-reaction system was established, and a novel Na 2 CO 3 -CaO co-roasting-leaching method was developed to enable selective separation of V and Cr. Combining DFT calculations, pure mineral roasting experiments, and actual vanadium slag roasting validation, the transformation mechanisms were elucidated: vanadium was converted into water-insoluble NaCaVO 4 and CaVO 3 , while chromium existed as water-soluble Na 2 CrO 4 during the Na 2 CO 3 -CaO co-roasting process. Under optimized conditions (roasting temperature 900 °C, duration 90 min, molar ratio n(CaO)/n(Na 2 CO 3 ) = 1), the average leaching efficiencies reached 84.23 % for Cr in the first-stage water leaching and 86.52 % for V in the second-stage ammonium bicarbonate leaching. The Cr concentration in the water leaching solution was 4.1 g/L (V: 0.7 g/L), whereas the V concentration in the ammonia leaching solution significantly increased to 7.1 g/L (Cr: 0.8 g/L). Impurity ions (Fe, Mn, Ti, Si) in both leaching solutions remained below 0.05 g/L. The remarkably low impurity levels substantially reduced purification costs, and the distinct concentration differences between V and Cr highlighted the selective separation advantages of the proposed process. These integrated characteristics provide critical feasibility support for industrial-scale implementation.
研究领域:
冶金工程
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环境科学
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产品关联
DOI
高影响因子
FOOD CHEMISTRY
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2019
·
IF 5.399
Jiaojiao Yin,Li Wang,Yuanyuan Chen,Dianfu Zhang,Abeer M. Hegazy,Xuezhen Zhang
In this study, bighead carp ( Aristichthys nobilis ) were exposed to waterborne Cr 6+ of 0.01, 0.1, 1 and 5 mg/L for 14 days and subsequently transferred to clean water for another 14 days. The Cr 6+ contents in some edible parts, such as dorsal muscle, ventral muscle and head were detected. The Cr 6+ concentrations in the three parts were in the order of: head > ventral muscle > dorsal muscle with significant increase during exposure period and remarkable decrease when kept at clean water during depuration stage. The head contained higher fat than that of muscle and the Cr 6+ levels of these parts showed significantly positive correlation with fat content, however, the Cr 6+ contents in the separated fat were extremely low. The Cr 6+ levels determined in tissues can tell a real story rather than the correlation coefficient. Fish head poses a higher potential health risk than muscle due to heavy metals pollution.
研究领域:
环境科学
·
毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2016
·
IF 3.205
Yushan Hou,Jianfang Wu,Elena Yu. Konysheva
Quantitative analysis of Cr-adsorption from a gas phase on CeO 2 , pure and doped BaCeO 3 was performed in combination with surface techniques and electrochemical impedance spectroscopy . The Cr-adsorption on BaCeO 3 is 3 times higher than on CeO 2 and it increases by 12–25% on In doping in Ba(Ce 1−x In x )O 3 (x = 0.1–0.3) in the temperature range of 600–700 °C. These perovskites adsorb chromium with the formation of a multi-phase surface layer containing BaCr 6+ O 4 and cerium oxide. Coexistence of small fractions of Cr 3+ and Cr 5+ cations in the surface layer was identified by X-ray photoelectron spectroscopy. The thickness of the surface layer and its morphology vary with temperature, affecting the conductivity of Ce containing perovskites below 700 °C. BaCrO 4 exhibits under air noticeably larger anisotropic thermal expansion than BaCeO 3 . The results indicate that high tolerance to Cr-gaseous species should be considered as an important criterion for further development of materials for proton-conducting SOFCs.
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Shakeel Ahmad,Feilong Gao,Honghong Lyu,Jingkang Ma,Beibei Zhao,Siyu Xu,Cholnam Ri,Jingchun Tang
Synthesizing new composites with better efficiency and stability from abundant sources offers an appealing prospect for removal of heavy metals and organic pollutants to address water pollution concerns. In this study, iron (Fe) and nitrogen (N) doped biochar (BC) composites were investigated for hexavalent chromium (Cr(VI)) and nitrobenzene (NB) removal. Specifically, temperature-dependent Fe 1 -N 1 -BC 1 composites were synthesized with different mass ratios of FeCl 3 as Fe, melamine as N, and pinewood sawdust (PWS) as BC precursors via carbothermal reduction at 300, 500, 700, and 900 °C. Detailed characterizations indicating low-temperature incorporated superior N and high-temperature incorporated more Fe species in Fe 1 -N 1 -BC 1 composites. The Cr(VI) and NB were removed with Fe 1 -N 1 -BC 1 , and experimental results attested with standard isotherm and kinetic models. The N species (pyridinic-N, pyrrolic-N, graphitic-N, quaternary-N, and oxidized-N) and Fe species (Fe 3 C, Fe 0 , Fe 2p 3/2 , and Fe 2p 1/2 ) in temperature-dependent Fe 1 -N 1 -BC 1 composites participated in pollutants removal. Mass ratio of 1:1:1 of Fe, N, and BC was effective, and under optimum conditions, low-temperature (Fe 1 -N 1 -BC 1 -300) and high-temperature (Fe 1 -N 1 -BC 1 -700) composites completely removed Cr(VI) and NB, respectively. In comparison to pinewood sawdust BC (PWBC) and composite of FeCl 3 with PWS (Fe-BC), melamine with PWS (N-BC), and FeCl 3 with melamine (Fe-N), the Fe 1 -N 1 -BC 1 was more efficient due to synergistic effect of Fe, N, and BC for better pollutant interaction and removal. Effect of different factors on pollutants removal with Fe 1 -N 1 -BC 1 was studied to reveal removal mechanism insights. Additionally, Fe 1 -N 1 -BC 1 showed better efficiency in simultaneous removal of Cr(VI) and NB, stability for > 4 months, reusability, and applicability for multiple pollutants. This study offers a benign approach for synthesizing and applying Fe 1 -N 1 -BC 1 for pollutants removal and exploring reaction mechanisms.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）