WATER RESEARCH
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2025
·
IF 12.4
Xian Zhao,Jia-Yi Wang,Yu-Qian Wang,Chen-Hao Cui,Xin Yan,Wei Dai,An-Ran Zhang,Zhen-Ying Zhang,Ding-Ding Tang,Yan Zhou,Qiong Qin,Ji-Wei Pang,Lu-Yan Zhang,Nan-Qi Ren,Jie Ding,Shan-Shan Yang
s Green rust (GR), a reductive iron-based mineral pivotal in soil and groundwater remediation, remains unexplored for wastewater treatment. This study reveals that high-pH-Fe(II) coagulation enables in-situ generation of stabilized GR, thereby enhancing the coagulation efficiency (> 90 % removal for diverse dyes). The formation mechanism includes three sequential stages: Initially, alkaline conditions facilitate abundant Fe(OH) 2 ; Subsequently, partial oxidation of Fe(II) by oxidants produces anoxic zones, where Fe(II)/Fe(III) co-precipitation initiates GR crystallization; Simultaneously, multivalent anions intercalate into GR interlayers, further enhancing GR stability through strong electrostatic interactions. GR-enhanced-Fe(II) coagulation demonstrates dual dyes removal mechanisms: direct reductive degradation of electrophilic moieties (e.g., azo bond) and adsorption-coprecipitation of macromolecules. Based on the mechanism insights, it is found that GR-enhanced-Fe(II) coagulation achieves unparalleled removal of both anionic and cationic dyes (nearly 100 % decolorization for 50 mg/L dye solutions) under anoxic conditions. HPLC-MS and DFT confirm GR-driven reductive cleavage of Reactive Red 2 into low-molecular-weight byproducts. Pilot and full-scale trials at a dyeing wastewater treatment plant concluded that GR-enhanced-Fe(II) coagulation achieves 53.5 % COD removal, outperforming conventional Fe(II) processes (46.5 %) under actual hydraulic and pollutant load fluctuations. This work expands coagulation theory and offers a cost-effective strategy for wastewater treatment, adaptable to diverse effluents while retaining operational simplicity.
研究领域:
环境科学
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水处理技术
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材料科学
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DOI
PubMed
高影响因子
Sustainability
·
2021
·Vol. 14
·期 1
·21
·
IF 3.251
Shuangshuang Zhang,Wenhui Zhang,Yazhen Wan
To remedy the widespread chromium (Cr) pollution in the environment, this study mainly used the ultrasonic-assisted co-precipitation and precipitation methods to prepare FeS-modified Fe-Al-layered double hydroxide (FeS/LDH) composite material. The experimental results showed that FeS/LDH has higher removal efficiency of Cr in aqueous solution and stronger anti-interference ability than unmodified LDH. Under the same reaction conditions, the removal efficiency of total Cr(Cr(T)) using LDH was 34.85%, and the removal efficiency of Cr(VI) was 46.76%. For FeS/LDH, the removal efficiency of Cr(T) and Cr(VI) reached 99.57% and 100%, respectively. The restoration of Cr(T) and Cr(VI) by FeS/LDH satisfied the Langmuir adsorption isotherm. The maximum adsorption capacity of Cr(T) and Cr(VI) achieved 102.9 mg/g and 147.7 mg/g. The efficient removal of Cr by FeS/LDH was mainly based on the triple synergistic effect of anion exchange between Cr(VI) and interlayer anions, redox of Cr(VI) with Fe2+and S2−, and co-precipitation of Fe3+and Cr3+.Keywords:chromium;FeS/LDH;double reduction;anti-interference;co-precipitation
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
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2022
·
IF 5.477
Tianhao Han,Weiwei Chen,Yawen Cai,Zhimin Lv,Yifeng Zhang,Xiaoli Tan
Background Due to the randomly distributed nature of uranium contamination, remediation strategies often concentrate on in-situ immobilization. Limestone can limit the migration of uranium through its spontaneous replacement reaction with phosphate, and achieve uranium immobilization. Methods In this study, the immobilization of uranium in the deposition process of hydroxyapatite was investigated. The effect of carbonate concentration on the reaction process was studied by adding Na 2 CO 3 . Significant findings The deposition process is accompanied by the immobilization of uranium by co-precipitation. The immobilization (92.6%) of uranium (0.52 mmol/L) is due to the formation of calcium uranyl phosphate, increasing carbonate concentration has a significant inhibitory effect on uranium immobilization, and the 50 Mm carbonate can reduce the uranium immobilization efficiency by nearly 20%. XRD, FTIR, Raman, XPS, EA and fluorescence spectroscopy proved that co-precipitation, complexation, and encapsulation were the main mechanisms of uranium immobilization. Through determining the ratios of type-A and type-B substitutions, it reveals the immobilization of uranium weakens due to the competition of carbonate and phosphate. Our study provides the deposition of uranium in the geosphere should be taken into account for remediation and radioactive pollution disposal.
研究领域:
环境科学
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放射性污染治理
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产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2022
·
IF 10.753
Xingwen Lu,Wang Xu,Qinghuai Zeng,Weizhen Liu,Fei Wang
Struvite precipitation is a promising strategy for the simultaneous recovery of nitrogen and phosphorus from waste streams. However, waste streams typically contain high amounts of metal contaminants, including Ni, which can be easily sequestered by struvite, but the behavior of Ni during struvite precipitation remains unclear. Thus, this study investigates the influence of Ni concentrations on struvite precipitation. The quantitative X-ray diffraction (QXRD) results revealed that the purity of struvite decreased from 96.6 to 41.1% with the Ni concentrations increased from 0.1–100 mg·L −1 . At lower Ni concentrations of 0.1–1 mg·L −1 , scanning electron microscopy (SEM) showed a roughened surface of struvite crystal, and this was combined with X-ray absorption near edge structure (XANES) data that indicated a stack of Ni-OH and Ni-PO 4 on struvite surface. At Ni concentrations of 10–25 mg·L −1 , Ni primarily crystalized as Ni-struvite (NiNH 4 PO 4 ·6H 2 O), as detected by QXRD. At higher Ni concentrations of 25–100 mg·L −1 , the co-precipitation of amorphous Ni phosphate(s) (e.g., Ni 3 (PO 4 ) 2 ) and Ni hydroxide (e.g., Ni(OH) 2 ) was identified by XANES. Specifically, the X-ray photoelectron spectroscopy (XPS) analysis detected the formation of amorphous Mg hydroxide(s) and phosphate(s) at Ni of 25–100 mg·L −1 . The overall results revealed that Ni formed Ni-OH and Ni-PO 4 on struvite surface at 0.1–1 mg·L −1 , whereas Ni precipitated as separated phases (e.g. Ni-struvite, Ni hydroxide and phosphate) at 10–100 mg·L −1 . The existence of Ni disturbed the crystal growth of struvite and promoted the formation of Ni-struvite, amorphous products during struvite formation.
研究领域:
环境科学
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化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2022
·
IF 6.633
Min Xu,Xiaoli Ma,Yahui Chen,Luzeng Hu,Bo Wang,Muqing Qiu
Nanoscale zero-valent iron/biochar (nZVI/biochar) has been widely utilized in environmental remediation due to its excellent removal efficiency, easy synthesis, low-cost and environmental friendliness. Herein, the removal and interaction mechanism of Cr(VI) removal on nZVI/biochar was investigated by macroscopic and microscopic techniques. Compared to nZVI (25.84 mg/g), the high removal capacity (63.29 mg/g at pH 4.5), excellent reusability and chemical stability of nZVI/biochar were due to various oxygen-bearing functional groups and synergetic interaction. According to analysis of X-ray photoelectron spectroscopy (XPS), X-ray absorption near-edge fine (XANES) and extended X-ray absorption fine structure (EXAFS) spectra, the interaction mechanism of Cr(VI) on nZVI/biochar followed adsorption (complexation, electrostatic interaction), reduction and co-precipitation process with increasing reaction time. These findings are crucial for the application of nZVI/biochar for removal of heavy metals in actual environmental cleanup.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ChemistrySelect
·
2025
·Vol. 10
·期 8
·e202406007
·
IF 2
Chenxi Li,Kang Li,Shina Li,Ruixin Ma
Graphical In this study, copper hexacyanoferrate (CsRb–CuHCF) was used as a precipitant. Results demonstrated that CsRb–CuHCF can efficiently separate Rb + and Cs + from the high-salty solutions. The enrichment factor was up to 384 before and after precipitation. The precipitant reacts first with Cs + and then gradually with Rb + and can be used for the separation of Cs + and Rb + from each other. Cesium (Cs) and rubidium (Rb) are important rare alkali metal elements that are scarce and dispersed in nature. They often coexist with high amounts of Na + and K + . In this study, copper hexacyanoferrate (CuHCF) was used as a co-precipitant to enrich Cs + and Rb + in a high-salt solution. The effect of parameters, such as type and dose of divalent metal ions, solution pH, material dropping speed, reaction time, and temperature, was investigated for the recovery rate of Cs + and Rb + . Results showed that the recovery rates of Cs + and Rb + were 99.78% and 88.84% at the optimal Cu 2+ /(Cs + +Rb + ) molar ratio of 0.5, respectively. The reaction could be completed within 10 min in pH 3–8. The detailed characterization of the Cs + and Rb + containing co-precipitants, CsRb–CuHCF, confirm a general formula of Cs 1.09 Rb 0.81 K 0.16 Cu 0.97 Fe(CN) 6 . The (Cs + +Rb + )/(Na + +K + ) increased significantly from 0.074 to 28.47 before and after precipitation, which realized the effective enrichment of Cs + and Rb + . Studies of the precipitation reaction mechanism showed that the precipitant reacted first with Cs + and then with Rb + . This process offers a promising avenue for the enrichment and separation of Cs + and Rb + from high-salty solutions.
研究领域:
化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
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IF 4.9
Longfei Xia,RiSheng Li,Menglin Yao,Xu Deng,Wen Sun,Miaomiao Du
In this study, micron Zero-valent Iron (mZVI), an affordable and well-dispersible reducing agent, was investigated for its potential application in removing Sb(V) from wastewater. Since Sb(V) primarily exists as Sb(OH) 6 - in aqueous solutions, the lower the pH, the more effective mZVI is in removing Sb(V). At a pH level of 3, mZVI (1.0 g/L) was able to remove more than 99 % of Sb(V) (20 mg/L) from the wastewater. The study also compared the influence of cations and anions on mZVI and found that anions had a greater impact on the material's performance. The paper further examined the impact of different heavy metal ions on mZVI and determined that the adsorption capacity of mZVI towards these ions follows the order of their reducing ability. Summarizing the removal mechanism of Sb(V) by mZVI, it was found that both adsorption and redox reactions played crucial roles and Sb(V) is ultimately removed from water through coprecipitation by combining with Fe-O on the mZVI surface. Theoretically, the maximum adsorption capacity of the mZVI material used in this study could reach 21.60 mg/g for Sb(V). This makes mZVI a promising environmental adsorption material and a potential solution for treating water pollution caused by antimony mining.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2016
·
IF 2.188
Siyuan CHEN,Jintai FAN,Liangjie PAN,Benxue JIANG,Xiaojian MAO,Rihong LI,Xinqiang YUAN,Xiongwei JIANG,Long ZHANG
Yb:Lu 3 Al 5 O 12 (Yb:LuAG) nano powders were synthesized with the co-precipitation method from cation (Lu 3+ , Yb 3+ , Al 3+ ) solution of different concentrations using NH 4 HCO 3 as the precipitant. The influence of cation concentration on the morphology and purity of the calcined powders was studied. Contrary to the conventional suggestion that recommends thin solution to obtain loosely agglomerated nano powders, results showed that thin cation (Lu+Yb+Al) concentration ≤0.08 mol/L led to formation of Al 2 O 3 and LuAP impurities in the obtained nano powders. By means of Tg/(DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM), the cause was revealed to be re-dissolution of Lu at high pH value that resulted from the decomposition of NH 4 HCO 3 . (Lu+Yb+Al) concentration of ∼0.24 mol/L was recommended to achieve pure Yb:LuAG nano powders. Transparent Yb:LuAG ceramics were fabricated with the prepared Yb:LuAG nano powders. The transmittance around 800 nm was 77.5%.
研究领域:
材料科学
·
光学材料
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2015
·Vol. 8
·期 8
·5363-5375
·
IF 2.651
Liangjie Pan,Benxue Jiang,Jintai Fan,Qiuhong Yang,Chunlin Zhou,Pande Zhang,Xiaojian Mao,Long Zhang
The synthesis of pure and well dispersed lutetium aluminum garnet (LuAG) powder is crucial and important for the preparation of LuAG transparent ceramics. In this paper, high purity and well dispersed LuAG powders have been synthesized via co-precipitation method with lutetium nitrate and aluminum nitrate as raw materials. Ammonium hydrogen carbonate (AHC) was used as the precipitant. The influence of aging time, pH value, and dripping speed on the prepared LuAG powders were investigated. It showed that long aging duration (>15 h) with high terminal pH value (>7.80) resulted in segregation of rhombus Lu precipitate and Al precipitate. By decreasing the initial pH value or accelerating the dripping speed, rhombus Lu precipitate was eliminated and pure LuAG nano powders were synthesized. High quality LuAG transparent ceramics with transmission >75% at 1064 nm were fabricated using these well dispersed nano LuAG powders.Keywords:co-precipitation method;single phase;pH values;LuAG powder;transparent ceramics
研究领域:
材料科学
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无机化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
·
2023
·
IF 7.8
Zibin Pan,Qingqiang Gao,Zuliang Chen
The elimination of arsenic (As) from arsenic-contaminated mine groundwater has become a worldwide problem because it causes environmental degradation and poses serious risks to human health. In this study, biosynthesized Fe/Cu nanoparticles (Fe/Cu NPs) were used for the simultaneous elimination of As(Ⅲ) and As(Ⅴ) from aqueous solution, resulting in their maximum amounts removed at 8.5 and 17.5 mg/g, respectively. SEM, FTIR, and XPS characterizations indicate that the Fe component on the Fe/Cu NPs acted as an adsorption and catalyst, while the Cu component mainly developed into a co-precipitation reaction with the As species, also facilitating the Fe catalytic processed. Meanwhile, adsorption isotherms , kinetics, and DFT calculations reveal that the removal of As(Ⅲ) was primarily physical/chemical adsorption and oxidation , while the elimination of As(Ⅴ) was co-precipitation and chemisorption. The most stable adsorption site, receiving 0.252 and 0.306 electrons from As(Ⅲ) and As(Ⅴ), respectively, was the unsaturated complexes of iron on the Fe/Cu NPs. Finally, the measurements and XPS results of Fe/Cu NPs in the treatment of groundwater show that the reduced capacity to remove As was attributed to a complex reaction system that disrupted the function of the Cu component, including co-precipitation and made the catalytic process possible. This explains there are differences in the reaction processes of biosynthetic Cu/Fe NPs in aqueous solution and groundwater.
研究领域:
环境科学
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纳米技术
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水处理
✓ 已验证
产品关联
DOI
高影响因子
BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY
·
2021
·Vol. 107
·期 1
·167-174
·
IF 2.151
Zhong Kai,Zhang Chaolan,Ren Siwei,Huang He,Rong Qun,Zhou Yongxin
Layered double hydroxides (LDHs) are promising soil contamination amendment agents for its efficient absorbing abilities. However, the application of LDHs in remediation of heavy metal contaminated soil are to be developed. In this study, we synthesized MgAlFe-LDHs by introducing Fe 3+ into interlayer of the MgAl-LDHs using co-precipitation method. X-ray diffraction (XRD), Fourier transform infrared spectrometer (FT-IR) and scanning electron microscope (SEM) were employed to characterized the micro structure of MgAlFe-LDHs. And then pot incubation and pilot experiments were conducted to investigate the heavy metal removal efficiencies of MgAlFe-LDHs and its potential being applicated in As contaminated soil amendment from a deserted arsenic plant site. Incubation experiments showed that the MgAlFe-LDHs had a higher removal efficiency on arsenic contaminated soil compared to other agents. And the results of pilot experiments indicated that the MgAlFe-LDHs can immobilize up to 90% of the As in soil with 5% (w/w) addition. Based on the results above, MgAlFe-LDHs are promising materials amending the heavy metal contaminated soil with practical application value.
研究领域:
环境科学
·
土壤学
✓ 已验证
DOI
PubMed
高影响因子
Catalysts
·
2019
·Vol. 9
·期 6
·519
·
IF 3.444
Jiaming Shao,Fawei Lin,Yan Li,Hairong Tang,Zhihua Wang,Peixi Liu,Guanyi Chen
NO oxidation was conducted over MnOx-CeO2catalysts, which were synthesized by the co-precipitation method. The calcination temperature and third metal doping were the main considerations. MnCe catalysts calcined at 350 °C and 450 °C attained the highest NO conversion efficiency, compared to 550 °C. XRD results suggested that the higher the calcination temperature, the higher the crystallization degree, which led to a negative effect on catalytic activity. Subsequently, Sn, Fe, Co, Cr, and Cu were separately doped into MnCe composites, but no improvement was observed for these trimetallic catalysts in NO conversion. Nevertheless, MnCeSn, MnCeFe, and MnCeCo still exhibited a desirable NO conversion efficiency, so they were tested under SO2addition together with MnCe catalyst. Among them, MnCeFe exhibited the highest NO conversion after whole poisoning testing. XPS results indicated that Fe could protect Mn and Ce metal oxides from being reduced during SO2poisoning process. Furthermore, in in-situ DRIFTS measurement, part of nitrate species maintained undestroyed on the MnCeFe catalyst surface after SO2poisoning. These characteristics reinforced that Fe dropping would achieve better performance under SO2atmosphere.Keywords:MnOx-CeO2;co-precipitation;NO oxidation;SO2resistance;metal addition
研究领域:
环境科学
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催化化学
✓ 已验证
DOI
高影响因子