ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
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2024
·Vol. 31
·期 14
·21279-21290
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IF 0
Xiong Ling,Zhang Fen,Yang Yanan,Ding Yuqing,Chen Shaohua
A novel adsorbent, deposited PPy on the DMI (PPy/DMI) composite, was successfully synthesized for Cr(VI) removal from aqueous solution. PPy/DMI composite was characterized by BET, SEM, TEM, XRD, and XPS. The SEM and TEM analyses revealed that DMI can greatly reduce the aggregation of PPy and significantly enhance its adsorption performance. The Cr(VI) removal was highly pH dependent. The high selectivity of PPy/DMI composite for Cr(VI) removal was found even in the presence of co-existing ions. The adsorption kinetic process followed the pseudo-second-order equation, demonstrating that the Cr(VI) adsorption behavior onto PPy/DMI is chemisorption. Furthermore, the intra-particle diffusion model implied that the adsorption was controlled by both liquid membrane diffusion and internal diffusion. The adsorption isotherm data fitted well with the Langmuir model with the maximum adsorption capacity (406.50 mg/g at 323 K) which was considerably higher than that of other PPy-based adsorbents. The Cr(VI) adsorption onto PPy/DMI composite was endothermic. The main mechanisms of Cr(VI) removal are involved in adsorption through electrostatic attractions, ion exchange, and in situ reduction. The results suggested that PPy/DMI composite could be a promising candidate for efficient Cr(VI) removal from aqueous solution. Graphical
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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水处理
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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2016
·
IF 3.138
Li Zhang,Hanjin Luo,Peipei Liu,Wei Fang,Junjie Geng
A novel adsorbent for removal of hexavalent chromium (Cr(VI)) from aqueous solutions has been successfully prepared by modifying graphene oxide/chitosan composite with disodium ethylenediaminetetraacetate (EDTA-2Na) (GEC). This modified composite was characterized by various technologies; including scanning electron microscopy (SEM), Transmission Electron Microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). Batch adsorption experiments were carried out to evaluate the adsorption of Cr(VI) by GEC under different conditions. The results indicate that the adsorption of Cr(VI) on GEC was highly pH-dependent, with the highest adsorption capacity (86.17 mg/g) occurring at pH 2. The kinetics of adsorption exhibited pseudo-second-order behavior. The adsorption data were well described by the Freundlich isotherm model. The adsorption capacity increased with increasing temperature. The calculated thermodynamic parameters indicate that the adsorption is a spontaneous, endothermic and feasible process. The further regeneration experiments showed the adsorption capacity of GEC for Cr(VI) decreased 5% after 7 times reuse, indicating the potential of the as-prepared material for practical application.
研究领域:
环境科学
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材料科学
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水处理
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吸附技术
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DOI
高影响因子
CHEMOSPHERE
·
2023
·
IF 8.8
Cui Shang,Youzheng Chai,Liang Peng,Jihai Shao,Hongli Huang,Anwei Chen
In-suit immobilization is one of the major strategies to remediate heavy metals contaminated soil with the effectiveness largely depends on the characteristics of the added chemical reagents/materials. In this study, chitosan stabilized FeS composite (CS–FeS) was prepared to evaluate the performance of remediating the high and toxic hexavalent chromium contaminated soil from the effectiveness and microbial response aspects. The characterization analysis confirmed the successful preparation of composite, and the introduction of chitosan successfully stabilized FeS to protect it from rapid oxidation as compared to bare FeS particles. With the addition dosage at 0.1%, about 85.6% and 81.3% of Cr(VI) was reduced in 3 d based on toxicity characteristic leaching procedure (TCLP) and CaCl 2 extraction, and the reduction efficiency increased to 96.6% and 94.8% in 7 d, respectively. The Cr(VI) was non-detected in the TCLP leachates with increase the CS-FeS composites to 0.5%. The percentages of HOAc-extractable Cr decreased from 25.17% to 6.12% accompanied with the increase in the residual Cr from 4.26% to 13.77% and improvement of soil enzyme activity under CS-FeS composites addition. Cr(VI) contamination reduced the diversity of microbial community in soil. Three dominate prokaryotic microorganisms , namely Proteobacteria , Actinobacteria and Firmicutes , were observed in Cr-contaminated soil. The addition of CS-FeS composites increased the microbial diversity especially for that in relative lower abundance. The relative abundance of Proteobacteria and Firmicute related to Cr-tolerance and reduction increased in CS-FeS composites added soils. Taking together, these results demonstrated the potential and promising of using the CS-FeS composites for Cr(VI) polluted soil remediation .
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PubMed
高影响因子
LANGMUIR
·
2023
·
IF 3.9
Shao-zhong Hu,Yu-fan Deng,Liang Li,Nan Zhang,Ting Huang,Yan-zhou Lei,Yong Wang
The rapid growth of industrialization has resulted in the release of large quantities of pollutants into the environment, especially dyes and heavy metals, which are environmentally hazardous for humans and animals. It is considered as the most promising and environmentally friendly route to develop green materials by using the green modification method, which has no negative impact on the environment. In this work, the green material of polylactic acid (PLA) was used as the substrate material, and a novel modification method of polydopamine (PDA)-assisted polyethyleneimine (PEI) grafting was developed. The electrospun PLA fibers are mainly composed of stereocomplex crystallites, which were achieved via the electrospinning of poly(l-lactic acid) and poly(d-lactic acid). The water-soluble PEI was grafted onto the PDA-modified PLA fibers through the glutaraldehyde-assisted cross-linking reaction. The prepared composite fibers can be degraded, which is environmentally friendly and meets the requirements of sustainable development. The potential application of such PLA composite fibers in wastewater treatment was intensively evaluated. The results show that at appropriate fabrication conditions (PDA concentration of 3 g·L–1 and a PEI molecular weight of 70,000 g·mol–1), the composite fibers exhibit the maximum adsorption capacities of 612 and 398.41 mg·g–1 for methyl orange (MO) and hexavalent chromium [Cr(VI)], respectively. Simultaneously, about 64.79% of Cr(VI) adsorbed on the composite fibers was reduced to Cr(III). The above results show that the PLA composite fibers have a good development prospect in the field of wastewater treatment.
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高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
·
2023
·
IF 6.8
Xiaofeng Jiang,Wenjun Long,Teng Xu,Jiayu Liu,Yuling Tang,Wenhua Zhang
Polyphenols, as an important category of natural organics, are ubiquitous in plants and structurally diverse. Batch experiments were conducted to investigate the role of natural polyphenol, such as gallic acid (GA) and tannic acid (TA), in the biochemical behavior of Cr(VI) in soil media. GA and TA can effectively convert Cr(VI) to Cr(III) under neutral conditions (pH 7.0). However, there are significant differences in the transport, leaching toxicity, and bioavailability of reduced Cr(III) between the two systems. UV–vis spectra, chromium (Cr) mass balance, speciation distribution, and X-ray photoelectron spectroscopy were used to explore the intrinsic mechanisms of Cr(VI) reduction and (im)mobilization in the presence of GA or TA. Results showed that the reduction of Cr(VI) by GA was accompanied by poor immobilization of reduced Cr(III), especially at high GA concentrations (4–10 g/L), which was associated with the formation of soluble Cr(III) complexes. After treatment with 4 g/L GA, 51.49 ± 3.04% of the Cr in GA system was mobilized as complexes into aqueous phase. In contrast, the reduction of Cr(VI) and the subsequent precipitation of reduced Cr(III) was dominant in the TA system. After treatment with 4 g/L TA, 97.24 ± 0.31% of the total Cr in the TA system was immobilized into soil phase and transformed into more stable fractions. Our findings provide new insights into how natural organics shape the fate and transport of Cr in soils, which also have substantial implications for the development of Cr sequestration technology.
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高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Qi Wang,Biao Xue,Meng Tan,Ningyi Li,Hao Zhou,Hao Du,Guoxiang Yang,Huaze Zhu,Qiang Li
Heterogeneous photocatalysis have attracted extensive attention in the field of environmental remediation. The low charge separation efficiency and poor light response of single semiconductor can be remarkably improved through forming heterojunction . The construction of ternary heterojunctions can further inhibit the recombination of photogenerated charge carriers by the separated redox active sites. A novel and highly efficient Ag 3 VO 4 -BiVO 4 /C 3 N 4 ternary heterojunction were successfully synthesized and characterized in terms of structure, chemical composition and photocatalytic properties. The photocatalytic activities of as-synthesized photocatalysts were evaluated by the photocatalytic reduction of Cr(VI) in the aqueous solution. The photocatalytic Cr(VI) reduction rate of ternary heterojunction is 19 times higher than that by single BiVO 4 . The lower pH, higher concentration of coexisted organics and stronger light intensity endowed photocatalysts with better photocatalytic performance. More Cr(VI) ions were remained in the solution with higher initial concentration of Cr(VI) under the same light irradiation. The Cr(VI) ions could also be totally removed by the ternary heterojunction even after five cycling tests showing good cycling stability. The internal electric field between Ag 3 VO 4 , BiVO 4 and graphitic carbon nitride (C 3 N 4 ) facilitated the separation of photogenerated electron/hole pairs. The suitable band alignments endow ternary heterojunction with isolated oxidation and reduction reactions due to the separated holes and electrons, meanwhile, suppressing charge carrier recombination. This research provides guidance for the rational design of multi-components heterojunction for photocatalytic environmental remediation.
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高影响因子
CHEMOSPHERE
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2023
·
IF 8.8
Lixin Li,Ying Lv,Chao Jia,Dawei Yin,Zilong Dong,Zhaoshun Zhan,Jiazhen Han,Jun Zhang
Traditional sludge disposal is currently restricted by the risk of secondary pollution. Sludge carbon material has gained widespread attention because of its low cost and environmentally sustainable properties. However, owing to the high ash content and low–energy density of sludge, sludge pyrolysis alone has certain limitations, and the performance of carbon materials needs to be improved. Herein, a sludge–cyanobacteria composite carbon (SCC) was easily synthesized, and the adsorption process of Cu(II) and Cr(VI) by SCC was examined. SCC-700-2-50% exhibited a high S BET (1047.54 m 2 /g) and developed pore structure rich in functional groups (such as –NH, –OH, and C–O). The combination of pore structure and functional groups improved the adsorption performance of SCC. The adsorption processes exhibited a synergistic effect in a binary system: the q m of Cu(II) and Cr(VI) were 386 mg/g and 341 mg/g, respectively, and the selectivity of Cu(II) adsorption by SCC was greater than Cr(VI). The adsorption process, examined by SEM-EDS, FTIR, and XPS analysis, indicated that Cu(II) as a cationic interface strengthens Cr(VI) adsorption through electrostatic interaction, and the anion Cr(VI) created a valid electrostatic shield against the electrostatic repulsion between H + and Cu(II), facilitating Cu(II) adsorption. SCC had great reusability: Cu(II) and Cr(VI) adsorption capacity were 90% and 84%, of the initial adsorption capacity, respectively, after six cycles. This study demonstrates the prospect of SCC as a valid adsorbent for multiple heavy metal contaminations removal.
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高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2023
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IF 5.2
Zhixiang Cui,Shengnan Tian,Xiaolong Liu,Qianting Wang,Sen Zeng,Junhui Si
The efficient elimination of toxic dye and Cr(VI) from wastewater by photocatalysis is still a challenge due to the unsatisfactory photocatalytic efficiency and difficult separation of the photocatalyst . Herein, the thermoplastic polyurethane (TPU) fiber membrane was prepared by electrospinning and then titanium dioxide (TiO 2 ) nanoparticles were loaded on the fiber membrane by ultrasonic-assisted method, followed by in-situ polymerizations of polyaniline (PANI) on the surface of the membrane. The synergistic effect of TiO 2 and PANI results in faster charge migration and more efficient separation of photogenerated charge carriers. Photocatalytic experiments revealed that TPU/TiO 2 /PANI fiber membranes were highly efficient for dye degradation and Cr(VI) reduction under visible light irradiation. 99.7 % of Congo red was degraded by TPU/TiO 2 /PANI membrane within 30 min, and the reaction rate reached 0.2 min −1 . The Cr(VI) reduction efficiency was up to 99.0 % within 25 min with a reaction rate of 0.128 min −1 . Additionally, the TPU/TiO 2 /PANI membrane exhibited a low loss in catalytic activity even after recycling 10 times, suggesting superior recycling stability compared to TPU/TiO 2 membrane. The result of the electron spin resonance (ESR) experiment showed that superoxide radicals (-O 2 - ) and hydroxyl radicals (-OH - ) were involved in the photocatalytic degradation process. The prepared TPU/TiO 2 /PANI fiber membrane combined with excellent photocatalytic capacity, good stability and easy recovery makes it a good candidate for removing dye and Cr(VI) from wastewater.
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高影响因子
APPLIED CLAY SCIENCE
·
2023
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IF 5.6
Fang Wang,Pingxiao Wu,Meiqing Chen,Jiayan Wu,Leiye Sun,Zhongbo Shang,Nengwu Zhu
Green rust (GR), as one of mixed-valent iron [Fe(II)-Fe(III)] minerals, has received a significant attention in recent years because it is an intrinsic and essential part of biogeochemical cycling of heavy metals and DOM . The transformation of GR is a key factor in altering the environmental behavior of heavy metals, and therefore, prediction of such transformation is critical for managing environmental quality. DOM and heavy metals are recognized to have a significant impact on iron oxide transformation. However, detailed information on these phenomena and mechanisms are still limited. In this study, Cr(VI) and oxalic acid (OA) widely distributed in the natural environment were selected representatives of heavy metals and DOM. The mechanism of their influence on GR transformation and their environmental significance were clarified. GR transformed to feroxyhyte under the impact of Cr(VI) and OA, and feroxyhyte did not transform to more crystalline iron oxides after 7 days. However, OA enhanced Fe dissolution and Cr(VI) reduction while weakening the immobilization of Cr on GR. SEM results demonstrated that OA addition resulted in the collapse of the feroxyhyte structure. SEM-EDS data indicated that Cr and OA were adsorbed on GR, suggesting that this can be an essential pathway for C and Cr sequestration during GR transformation. This study reveals Cr(VI) not only favors the formation of feroxyhyte, but also stabilizes the mineral to prevent transformation and meanwhile indicates the mechanisms of organic matter interactions with iron oxide and the environmental behavior of C and Cr during the iron oxide transformation processes.
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高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2023
·
IF 9.8
Huimin You,Changlin Cao,Xiaoli Sun,Baoquan Huang,Qingrong Qian,Qinghua Chen
Microplastics (MPs) are emerging contaminants with growing concerns due to their potential adverse effects on the environment. However, understanding the aging properties and adsorption behavior of MPs is still limited. In this study, we investigated the correlation between the adsorption capacity, aging stages, and aging properties of polyethylene MPs using a correlation equation. Our results revealed that the trends of O/C ratio and contact angle of polyethylene MPs with aging time were fitted to be linear under xenon lamp accelerated aging conditions. Conversely, the trends of other properties such as particle size, crystallinity , and molecular weight with time were fitted to conform to the Boltzmann equation. Moreover, the aging curve data for carbonyl index and molecular weight (M w ) perfectly matched, confirming M w play a crucial role in verifying the aging process. Additionally, the adsorption amount of polyethylene MPs increased sharply with the increase of aging ages, reaching up to 1.850 mg/g. The adsorption data fit well to the pseudo-second-order kinetics and Langmuir model, suggesting that the adsorption process is dominated by chemisorption . The low pH and low salt concentration is beneficial to the adsorption capacity of MPs onto Cr(VI). Further, a relationship equation was established to predict adsorption risk at different aging stages. These findings provide new insights into the impact of aging on pollutants transport and the fate of MPs, enabling the prediction of adsorption risk of MPs at different aging stages in water environments.
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高影响因子
NEW JOURNAL OF CHEMISTRY
·
2023
·Vol. 47
·期 29
·13952-13962
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IF 3.3
Dehong Bai,Ziyu Xue,Shaohui Li,Ran Meng,Dongxia Zhang,Xibin Zhou
Chromate (Cr(VI)) is a highly toxic heavy metal ion that not only endangers human health but also causes environmental pollution. To control and remove Cr(VI) from water more effectively, we report a simple, novel, and rapid detection technique for Cr(VI) in water based on an iron-manganese bimetal-metal organic framework (FexMny-MOF). Firstly, the synthesized FexMny-MOF has a large specific surface area and porosity; for the first time, an MOF with dual mimic enzyme properties is reported, which can catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) to the blue product in the presence or absence of H2O2. Interestingly, the mimic enzyme properties of FexMny-MOF are enhanced than those of Fe-MOF and Mn-MOF. The free energies of elementary reactions and adsorption energies (Eads) of H2O2 and O2 adsorbed on different materials were calculated by density functional theory (DFT) to verify the mechanism of action of FexMny-MOF. The Fe1Mn1-MOF mimics oxidase-like oxidation of TMB; 8-hydroxyquinoline (8-HQ) is used as the inhibitor of TMB oxidation, and the specific interaction between 8-HQ and Cr(VI) weakens the inhibition of 8-HQ on TMB oxidation to achieve the detection of Cr(VI). The established method has high sensitivity and selectivity with a detection limit of 51 nM and a linear range of 80–3500 nM. This method has been successfully applied to the determination of Cr(VI) in tap water and the Yellow River, showing its great potential in environmental monitoring.
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高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2023
·
IF 4.7
Wen Wang,Liqiang Qi,Song Han,Hejin Yuan
A new chitosan-trithiocyanuric composite (CS@TMT) was synthesized by graft copolymerization using chloroacetyl chloride as the cross-linking agent. Using response surface analysis, the optimal conditions for the synthesis of CS@TMT were determined as: chloroacetyl chloride concentration of 2.0 mol/L, trithiocyanuric acid (TMT) addition of 7.0 g, and reaction temperature of 70 °C. The successful preparation of CS@TMT was confirmed FTIR spectrum, 13C NMR spectrum, SEM mapping, EDS, XRD and XPS. At ambient temperature (25 °C, pH=6.0, Catalyst dosage=1.0 g/L), the maximum Cr(VI) and Pb(II) adsorption amount of CS@TMT were 194.76 and 101.39 mg/g, respectively, compared to CS (97.15 and 69.76 mg/g). The Cr(VI) and Pb(II) removal process of CS@TMT was better fitted by the pseudo-second-order kinetic model and Langmuir model, and the adsorption process was spontaneous, endothermic and disordered. Under the reduction mechanism, 69.32% of Cr(VI) was reduced to Cr(III) by -SH and –OH group on CS@TMT.
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高影响因子
危险品化学品经营许可证（带存储）