JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2022
·
IF 8.91
Xuyin Huang,Xiaojun Niu,Dongqing Zhang,Xiaoqin Li,Haoshen Li,Ziyuan Wang,Zhang Lin,Mingli Fu
While nanoscale zero-valent iron modified biochar (nZVI-BC) have been widely investigated for the removal of heavy metals , the corrosion products of nZVI and their interaction with heavy metals have not been revealed yet. In this paper, nZVI-BC was synthesized and applied for the removal of Cr(VI). Batch experiments indicated that the adsorption of Cr(VI) fit Langmuir isotherm, with the maximum removal capacity at 172.4 mg/g at pH 2.0. SEM-EDS, BET, XRD , FT-IR, Raman and XPS investigation suggested that reduction of Cr(VI) to Cr(III) was the major removal mechanism. pH played an important role on the corrosion of nZVI-BC, at pH 4.5 and 2.0, FeOOH and Fe 3 O 4 were detected as the major iron oxide , respectively. Therefore, FeOOH-BC and Fe 3 O 4 -BC were further prepared and their interaction with Cr were studied. Combining with DFT calculations, it revealed that Fe 3 O 4 has higher adsorption capacity and was responsible for the effective removal of Cr(VI) through electrostatic attraction and reduction under acidic conditions. However, Fe 3 O 4 will continue to convert to the more stable FeOOH, which is the key to for the subsequent stabilization of the reduced Cr(III). The results showed that the oxide corrosion products of nZVI-BC were subjected to the environment, which will eventually affect the fate and transport of the adsorbed heavy metal.
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高影响因子
Carbon Neutrality
·
2024
·Vol. 3
·期 1
·1-16
·
IF 0
Liu Xinghui,Naraginti Saraschandra,Zhang Fuchun,Sathishkumar Kuppusamy,Saxena Kuldeep K.,Guo Xiang
Environmental contamination by hexavalent chromium (Cr(VI)) and antibiotic drug residues pose significant challenges to public health and ecosystems. This study investigates the application of CoTiO 3 /BiVO 4 @MIL-Fe(53) (CT/BV@Fe-MOF) for the reduction of Cr(VI) and degradation of tetracycline (TCL) under visible light. After grafting an iron-based metal–organic framework MIL-Fe(53) on a modified CoTiO 3 /BiVO 4 composite, the photogenerated electrons could easily be transferred from CoTiO 3 to BiVO 4 /Fe-MOF species via interfacial charge transfer. UV–vis diffuse reflectance spectroscopy showed that charge carriers were formed in response to visible light absorption. The effect of different operating parameters, including catalyst load, pH, initial Cr(VI), and TCL concentration, was systematically evaluated during the photocatalytic process. The CT/BV@Fe-MOF composite exhibited 98.7% reduction efficiency in Cr(VI) (50 ppm) and 97.5% degradation efficiency towards TCL (30 ppm) within 90 min, resulting in a greater efficiency than the pristine CoTiO 3 , BiVO 4 , and Fe-MOF materials. The CT/BV@Fe-MOF composite displayed excellent stability over six cycles, highlighting its potential for practical applications. In addition, the plausible degradation pathway of TCL was evaluated using LC-ESI/MS analysis, while the TEST program was utilized to investigate the toxicity of the products generated during the degradation process.
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Journal of Materials Chemistry A
·
2014
·Vol. 2
·期 31
·12561-12570
·
IF 0
Jian Hua Chen,Hai Tao Xing,Hong Xu Guo,Wen Weng,Shi Rong Hu,Shun Xing Li,Yi Hong Huang,Xue Sun,Zhen Bo Su
In this study, we prepare a polyethyleneimine (PEI) and graphene oxide (GO) composite adsorbent through an amidation reaction between the amine groups of the PEI and the carboxyl groups of the GO. Adsorption performance of the PEI–GO was tested by removing Cr(VI) ions from aqueous solution. The physico-chemical properties of the GO, pristine and Cr(VI) ions-loaded PEI–GO were investigated by FT-IR, SEM-EDX and XPS methods. To investigate the adsorption kinetics of Cr(VI) ions onto this newly developed PEI–GO, we performed a batch of experiments under different adsorption conditions: content of the PEI in the PEI–GO, solution pH, initial Cr(VI) ion concentration, adsorption temperature and contact time. The prepared PEI–GO exhibited an encouraging uptake capacity of 539.53 mg g−1. The adsorption process was fast, within the first 1 h, Cr(VI) ion adsorption onto the PEI–GO was about 71%, and the adsorption equilibrium could be obtained within 14 h. Kinetics experiments indicated that the adsorption process could be described by the pseudo-second-order kinetic model. Furthermore, our adsorption equilibrium data fit the Langmuir isotherms well (R2 > 0.99). The removal mechanism of Cr(VI) ions from the solution consists of two steps: (1) Cr(VI) ions bind to the 4PEI–GO composite by electrostatic interaction between the negatively charged Cr(VI) ion species and the protonated amine groups of the 4PEI–GO; and (2) a few Cr(VI) ions were reduced to Cr(III) ions with the assistance of π electrons on the carbocyclic six-membered ring of the 4PEI–GO and then bind on the 4PEI–GO by the electrostatic attraction between Cr(III) ions and negatively charged groups (COO−) of the 4PEI–GO. Based on the results obtained in this work, it can be concluded that the prepared PEI–GO can be an effective and potential adsorbent for removing Cr(VI) ions from an aqueous solution.
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CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Changwei Bai,Gang Yang,Shirong Zhang,Shihuai Deng,Yanzong Zhang,Chao Chen,Jingsong He,Min Xu,Lulu Long
A novel electrocatalytic anode (ECA)/α-MnO 2 /peroxymonosulfate (PMS) synergistic system was developed and evaluated for the removal of combined tetracycline (TC) and hexavalent chromium (Cr(VI)) pollution from waste waters. The factors affecting the efficiency of the removal of the combined pollutants, such as the synthesis time of the electrode, the amounts of raw materials, the PMS dose, the voltage, the initial pH and the coexisting ions were investigated. The breakdown products of PMS in the ECA/α-MnO 2 /PMS system improved the conductivity of the solution and the electrical current promoted the conversion of the valence state of Mn ions, resulting in a synergistic effect between the ECA and PMS activation processes, which improved the efficiency of removal of TC. The cathode chamber was fully utilized to simultaneously reduce Cr(VI). Synergistic effects occur in the ECA/α-MnO 2 /PMS system in appropriate ranges of the voltage or PMS dose, although the efficiency of the removal of TC depends mainly on the electrical current in the system. Both hydroxyl (•OH) and sulfate (SO 4 •− ) radicals played important parts in the degradation of TC. The main degradation products of TC were identified and degradation pathways proposed. The synergistic effects between the ECA process and a Fenton-like process was studied, providing a new approach for the study of electro-Fenton technology and the removal of combinations of TC and Cr(VI) from waste waters.
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高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2019
·
IF 4.784
Lanlan Li,Zhiyang Wei,Xiaowei Liu,Yunhe Yang,Chenxun Deng,Zhimin Yu,Zhi Guo,Jianghong Shi,Chengzhu Zhu,Wei Guo,Zhenjie Sun
Chitosan (CS) is an attractive bio-adsorbent in pollutant removal due to its environment-friendly properties and abundant adsorption sites. However, the weak mechanical properties and strong dissolubility in acidic conditions of CS hinder its wide application. Herein, a facile method was proposed to fabricate polydopamine (PDA) and CS cross-linked graphene oxide (GO) (GO/CS/PDA) composite aerogel for Cr (VI) removal. GO was cross-linked with CS, forming a reinforced and three-dimensional macroporous structure; the introduced PDA was simultaneously cross-linked with CS and GO, providing more abundant nanopores and active sites for Cr(VI) removal. Based on the batch experiment results, GO/CS/PDA exhibited an optimized mass ratio (1:20:2) of GO, CS, and PDA for the most effective Cr(VI) adsorption; the adsorption removal rate of Cr(VI) was pH dependent, with the highest removal rate at pH = 3.0. The pseudo-second-order kinetic and Freundlich models were more suitable for fitting the adsorption kinetics and adsorption isotherms, respectively, and the maximum adsorption capacity for GO/CS/PDA was 312.05 mg/g at 298 K. Thermodynamics parameters indicated that the adsorption was a spontaneous and exothermic process. The excellent mechanical integrity and reusable adsorption performance of GO/CS/PDA promise the adsorbent with satisfactory reusability.
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高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Xiaoyu Lin,Xi He,Ling Lei,Yufeng Zhao,Longzhe Cui,Guiping Wu
Cr(VI)-contaminated water poses a serious threat to the environment. In this study, capsule-type biosorbent Aliquat-336-filled chitosan capsules (AFCCs) were prepared by a simple and gentle method for more efficient and eco-friendly removal of Cr(VI). The experimental results show that the uptake of Cr(VI) by AFCCs increased with increasing Aliquat-336 content. The AFCCs show excellent stability under acidic conditions, and the maximum adsorption capacity was reached at a pH of 2. The maximum adsorption capacity of AFCCs for Cr(VI) was 110.94 ± 5.07 mg/g at 20 °C, which was calculated based on the Langmuir model. The kinetic results show that the adsorption rate control process changed from liquid film diffusion to a chemical reaction with increasing shaking rate. In addition, the AFCCs and adsorption-reduction mechanism of Cr(VI) were characterized by digital photography, electron microscope , zeta potential , Fourier-transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The results indicated that the electrostatic attraction between quaternary amine groups in Aliquat-336 and Cr(VI) anions plays a major role in the removal of Cr(VI). Subsequently, the adsorbed Cr(VI) obtained electrons from C C/C H and NH 3 + / NH 2 + were reduced to Cr(III), while C C/C H and NH 3 + / NH 2 + were oxidized to C O, C O, =NH + , =N and N O, respectively.
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高影响因子
JOURNAL OF VINYL & ADDITIVE TECHNOLOGY
·
2021
·Vol. 27
·期 3
·640-654
·
IF 1.993
Xiaoqi Liu,Yan Liu,Ting'an Zhang
This study aimed to prepare an efficient, cost-effective, and separable magnetic zeolite/chitosan composite (MZFA/CS) adsorbent from solid waste to deal with the water pollution of Cr(VI). The MZFA/CS was characterized by X-ray fluorescence (XRF), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and vibrating sample magnetometer (VSM) techniques. Then, the effect of pH, temperature, initial concentration of Cr(VI) ions, and contact time was considered in the study. For a sorbent dose of 0.1 g in 50 mL of a Cr(VI) solution, at a contact time of 30 min, temperature of 30°C, and a pH of 3, an adsorption capacity ( q e ) of 16.96 mg g −1 was achieved. Adsorption kinetics and isotherm data obtained for all adsorption systems were well-fitted by pseudo-second-order and Langmuir models, respectively. The thermodynamic study suggested that the adsorption process is spontaneous and endothermic in nature. In summary, the adsorbent with better separability ( Ms = 16.83 emu g −1 ) and adsorbability was successfully fabricated.
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高影响因子
Journal of Cleaner Production
·
2022
·
IF 11.072
Sun Qian,Wang Changlong,Zhang Lixin,Yang Yanzhao
The high pathogenicity to organisms and high destructiveness in the natural environment determine the utmost importance of removing Cr(VI) from water. Herein, thiourea crosslinked-amino modified graphene nanoflakes (TAGN) was prepared by simple ring opening reaction and silanization reaction and the Cr(VI) adsorption performance was investigated. Results manifested that TAGN presented three-dimensional porous structure with abundant folds and avoided agglomeration. The adsorption experiments indicated that the optimal test pH value was 2 and the most suitable adsorbent dosage was 1 g/L. Under the optimum adsorption conditions, TAGN exhibited an outstanding adsorption capacity of 193.77 mg/g for Cr(VI) in water. Various characterizations and tests such as Zeta potential , FTIR, XPS as well as isotherms and kinetics revealed that the adsorption of TAGN for Cr(VI) was more consistent with Freundlich isotherm model and pseudo-second-order kinetic model , confirming a multilayer chemisorption process dominated by multiple combination mechanisms: electrostatic interaction, reduction reaction, complexation and hydrogen bonding interaction. Under the condition of coexistence of multiple metal ions , the TAGN could still maintain superb selectivity of 63.9% towards Cr(VI). After ten cycling test, 81.8% removal efficiency of Cr(VI) was guaranteed. Therefore, TAGN possessed high adsorption capacity , excellent selectivity and prominent cyclic regeneration ability. This work provided a promising nanosorbent for the field of water cleaning, especially for the elimination of heavy metal ions .
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高影响因子
MATERIALS RESEARCH BULLETIN
·
2018
·
IF 2.873
Xiao Jiang,Qing-Da An,Zuo-Yi Xiao,Shang-Ru Zhai,Zhan Shi
A cost-effective and chemically modified biological adsorbent based on agricultural wasted husks for heavy metal removal was fabricated by coating with Polydopamine–Polyethylenimine via the mussel inspired chemistry. Batch and fixed bed column adsorption experiments were carried out to explore the sorption capacity and potency of industrial application. The batch results indicated that the maximum adsorption capacity reached 42.8 mg/g which is much larger than most adsorbents based on bioresource and agricultural wastes for Cr(VI) removal in aqueous solution simultaneously with excellent recycling performance. In column adsorption experiments, it exhibited high mechanical stability and applied potential. The equilibrium time was 9130 min under the flow rate of 1 ml/min, and reached the equilibrium adsorption capacity of 47.14 mg/g. The breakthrough curves ploted by the data of fixed bed experiments under different flow rates (1 ml/min & 2 ml/min) fitted the Thomas model with R 2 of 0.9510 and 0.9437 respectively.
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高影响因子
AQUATIC TOXICOLOGY
·
2015
·
IF 3.451
Hongxing Chen,Jinling Cao,Lixia Li,Xing Wu,Ran Bi,Paul L. Klerks,Lingtian Xie
Maternal transfer of metals can be an important exposure route for animals. The maternal transfer of Cr and its effects on reproduction in fish are still largely unknown. In this study, Japanese medaka were exposed to a sublethal Cr(VI) concentration for 6 days (acute) and for 3 months (chronic). Chromium accumulation in the gonads, maternal transfer of Cr, and effects of Cr on the reproduction, histopathology and expressions of antioxidants in the gonads were evaluated. Both acute and chronic exposures resulted in significant Cr accumulation in gonads, eggs and larvae. In chronic Cr-exposed fish, approximately 61% of the Cr accumulated in the ovary was depurated by spawning during the first 3 days after exposure, suggesting that maternal transfer is a very important pathway for accumulation in offspring. The chronic exposure caused decreases in body weight, standard length, gonad weight, gonad-somatic index (GSI) and fecundity. The last of these was most severely affected: the total number of broods and eggs per female decreased by 57.1% and 75.9%, respectively. Moreover, egg weight and fertilization rate were also reduced (by approximately 20%) following chronic Cr(VI) exposure. Histopathological analyses showed that the Cr exposure resulted in the onset of follicular atresia and a reduction in the number of mature oocytes, along with a reduction in abundance of mature spermatozoa in testes. The GSH/GSSG ratio was greatly elevated after chronic Cr(VI) exposure, implying that GSH played a role in scavenging the reactive oxygen species generated by the reduction of Cr(VI) inside cells. This study provides evidence for the maternal transfer of Cr, highlights the importance of spawning in Cr depuration from the ovary, and demonstrates that chronic Cr(VI) exposure has serious impacts on reproduction in the Japanese medaka. Our results suggest that the issue of chronic Cr pollution deserves more attention than it has received to date.
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高影响因子
Nanoscale
·
2025
·
IF 5.1
Wei Zhao,Yuxiang Yang,Yanbin Li,Yimin Liu,Yuezhou Wei,Xinpeng Wang,Deqian Zeng
The advancement of efficient photocatalysts is essential for tackling global energy and environmental issues. In this work, a unique sheet-on-sheet Cd(OH)2/CdS photocatalyst was synthesized via a facile solution strategy, demonstrating significantly improved photocatalytic performance for H2 generation and Cr(VI) reduction. The optimal 5% Cd(OH)2/CdS obtained an impressive H2 production rate of 3475 μmol·g-1·h-1 under visible light, marking a 6.3 times increase compared to CdS. Additionally, the kinetics of Cr(VI) reduction were markedly accelerated, with a rate constant of 0.2803 min-1, representing a 5.7 times improvement over pure CdS. Moreover, the 2D/2D Cd(OH)2/CdS photocatalyst exhibited exceptional stability, maintaining high photocatalytic activity over multiple reaction cycles. Experimental findings and DFT calculations revealed the charge transfer mechanism between CdS nanosheets and Cd(OH)2 cocatalyst. This work provides insights into designing high-performance CdS-based nanophotocatalysts for water splitting and environmental remediation.
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Yangshuo Sun,Guiyang Jiang,Yiming Zhou,Leilin Shu,Jiarui Li,Longcheng Liu,Junzhe Zhang,Xunrui Cheng,Yiyun Liu,Xiaoyan Xu,Zhi Zhu,Junshan Liu,Jing Zhang,Bo Sheng,Zhengyan Wu
This study successfully employed an electric field-driven physical technique to load nanoscale zero-valent iron (NZVI) onto a polyvinylidene fluoride (PVDF) membrane, resulting in a highly dispersed and stable NZVI-PVDF composite membrane (ENP). This method avoids the generation of toxic substances and significantly suppresses NZVI aggregation and oxidation, making it highly effective for the reduction of Cr(VI) in wastewater. SEM and AFM analyses revealed that, compared to conventional loading methods, this technique effectively reduces NZVI agglomeration. The resulting NZVI particles have an average diameter of 17.29 nm, while the root mean square roughness (Sq) of the membrane surface is 127.338 nm, ensuring a higher availability of Cr(VI) reduction-active sites. Moreover, after NZVI loading, the surface contact angle of the PVDF membrane decreased from 77.4° to 63.1°, indicating enhanced hydrophilicity. Cr(VI) reduction experimental results indicate that under optimal conditions with an applied voltage of 6 kV, pH 2, temperature of 25 °C, and atmospheric pressure, the ENP membrane achieved a Cr(VI) removal efficiency of 99.8 % within 1 h for an initial Cr(VI) concentration of 100 mg/L. These findings demonstrate that the electric field-driven NZVI loading approach will provide a promising, cost-effective, and environmentally friendly strategy for industrial wastewater treatment. It effectively overcomes the issue of NZVI aggregation while expanding its practical applications in water treatment technologies.
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）