SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Qi Liu,Mingqing Zhang,Yijun Cao,Biao Peng,Joshua Bosco Barvor
In gold-processing plants, the final tailing containing metal cyanide species is typically treated using various oxidation methods to produce the main source of process water, which is subsequently recycled to the upstream units, such as flotation units. In some gold-processing plants, a considerable amount of metal cyanide species such as zinc cyanide remains in process water, despite the cyanide destruction process. Because residual zinc cyanide complexes can depress gold flotation, the amount of process water must be decreased such that it can be recycled to a flotation circuit. Previous studies report that the critical concentration of zinc cyanide, measured based on the total cyanide concentration during flotation depression, is 0.4 mmol/L. In the present study, the feasibility of using quaternary ammonium salts to precipitate zinc cyanide complexes to less than the critical concentration was studied. The results showed that 92.17% of 60 mg/L of cyanide and 88.86% of 50 mg/L of zinc (molar ratio Zn/CN = 1:3) can be removed using 0.4 g/L of octadecyl trimethyl ammonium bromide at a pH of 10. The concentration of the residual CN cyanide was less than the critical concentration. This indicates that the abovementioned process is effective when nonpolar organic contaminants and moderate amounts of salt (<50 mmol/L) are present. This work revealed that the precipitation process can be used as an advanced treatment method for process water subjected to oxidation treatment.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
SYNTHETIC COMMUNICATIONS
·
2023
·
IF 2.1
Yulu Fu,Tian Fu,Chao Duan,Jie Chi,Hongshe Wang
A highly efficient, one-pot, three-component Strecker reaction for the synthesis of α-aminonitriles from carbonyl compounds, amines, and potassium hexacyanoferrate (II) (K4[Fe(CN)6]) in the presence of a catalytic amount of humic acid catalyst in water at room temperature has been developed. Advantages of this methodology are use of inexpensive, commercially available, environmentally friendly and reusable organocatalyst, environmentally benign and inexpensive cyanide source, simple experimental and work-up procedure, high yields, room temperature reaction, water as a green solvent and scaled-up synthesis.
研究领域:
有机化学
·
绿色化学
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2024
·Vol. 15
·期 1
·1-12
·
IF 14.7
Liu Tao,Lan Cheng,Tang Min,Li Mengxin,Xu Yitao,Yang Hangrui,Deng Qingyue,Jiang Wenchuan,Zhao Zhiyu,Wu Yifan,Xie Heping
Seawater direct electrolysis (SDE) using renewable energy provides a sustainable pathway to harness abundant oceanic hydrogen resources. However, the side-reaction of the chlorine electro-oxidation reaction (ClOR) severely decreased direct electrolysis efficiency of seawater and gradually corrodes the anode. In this study, a redox-mediated strategy is introduced to suppress the ClOR, and a decoupled seawater direct electrolysis (DSDE) system incorporating a separate O 2 evolution reactor is established. Ferricyanide/ferrocyanide ([Fe(CN) 6 ] 3−/4− ) serves as an electron-mediator between the cell and the reactor, thereby enabling a more dynamically favorable half-reaction to supplant the traditional oxygen evolution reaction (OER). This alteration involves a straightforward, single-electron-transfer anodic reaction without gas precipitation and effectively eliminates the generation of chlorine-containing byproducts. By operating at low voltages (~1.37 V at 10 mA cm −2 and ~1.57 V at 100 mA cm −2 ) and maintaining stability even in a Cl − -saturated seawater electrolyte, this system has the potential of undergoing decoupled seawater electrolysis with zero chlorine emissions. Further improvements in the high-performance redox-mediators and catalysts can provide enhanced cost-effectiveness and sustainability of the DSDE system.
研究领域:
能源科学
·
环境科学
·
电化学
✓ 已验证
DOI
PubMed
高影响因子
INTERNATIONAL BIODETERIORATION & BIODEGRADATION
·
2025
·
IF 4.1
Qingyun Li,Shaohui Yan,Zhengfeng Jiang,Liang Xian,Jianjia Du,Haibo Liu,Youyan Liu
Cyanide and phenol are highly toxic chemicals that exert severe inhibitory effects on microorganisms, posing significant challenges for their removal by biological methods in coexistent systems. In this study, we successfully isolated a bacterial strain named JF101, identified as Alcaligenes faecalis , which was capable of degrading both cyanide and phenol. The interactions between cyanide and phenol during biodegradation were investigated. It was found that the presence of 100 mg/L cyanide significantly enhanced the degradation of phenol, leading to the complete degradation of 1000 mg/L phenol within 86 h. In contrast, only 21.9% of phenol was degraded in the absence of cyanide. Additionally, the presence of phenol had minimal impact on cyanide degradation; a concentration of 100 mg/L cyanide could be rapidly and completely degraded within 40 min even in the presence of up to 1000 mg/L phenol. Five empirical kinetic models of Haldane, Aiba, Edward, Yano, and Webb were employed to describe the degradation processes of phenol and cyanide in both single-substrate and dual-substrate systems. The putative degrading enzymes, degradation products, and pathways associated with the co-degradation of cyanide and phenol were systematically analyzed. The formamide and NH 4 + -N produced from the rapid degradation of cyanide served as nitrogen sources, facilitating the resumed growth of strain JF101 and enhancing phenol degradation.
研究领域:
环境微生物学
·
污染治理
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
·
2023
·
IF 11.1
Kang Li,Junjie Xie,Zhuonan Shi,Changli Min,Zichen Yin,Ruixin Ma,Shina Li
Rubidium and cesium are highly-priced and important rare alkali elements but they always co-exist with large amount of sodium and potassium in a complex system resulting very difficult and expensive to recover. Hexacyanoferrates (MHCFs) is one of the most efficient methods to separate Rb + and Cs + if we don't consider certain drawbacks such as too small particle size and too viscous liquids to be precipitated. In this study, a new kind of hexacyanoferrate, magnesium (II) hexacyanoferrate (RbCs–MgHCF) has been fabricated at room temperature and applied for the first time to recover Rb + and Cs + from high-salty solutions. Compared with traditional divalent transition elements, such as CuHCFs, ZnHCFs, NiHCFs, CoHCFs or FeHCFs, RbCs–MgHCF had excellent precipitation property and large particle size of about 300 nm. The structure, morphology and composition were characterized by Fourier transform infrared (FTIR), X-ray diffraction (XRD), Scanning electron microscopy (SEM), Inductively coupled plasma (ICP), and Energy dispersive spectroscopy (EDS). The effects of various factors (divalent metal cations, surfactant, Mg 2+ /(Rb + +Cs + ) mole ratio, pH value and titration rate) on the recovery of Rb + and Cs + were explored in 50 mL batch experiments. Scale-up experiment were conducted in 6 and 18 L. Results identified that deposition ratio for Cs + and Rb + were 99% and 95% among pH ranges of 4.0–11.0. The composition of RbCs–MgHCF was confirmed to be Rb 0.61 Cs 1.20 K 0.17 Mg 1.01 Fe(CN) 6 by ICP and EDS and the synthesis mechanism of RbCs–MgHCF is proposed.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Mining Metallurgy & Exploration
·
2024
·Vol. 41
·期 2
·1089-1097
·
IF 1.5
Junjie Xie,Kang Li,Zhuonan Shi,Changli Min,Shina Li,Zichen Yin,Ruixin Ma
Cesium and rubidium were effectively separated by zinc ferrocyanide coprecipitation method, and the effect of precipitant addition amount on the separation of cesium and rubidium was studied. Under the conditions of Zn/Cs molar ratio of 0.45 and Zn/Fe molar ratio of 1, the precipitation rate of cesium is 84.01% and the separation factor of Cs/Rb is 164.65. The thermogravimetric curves of the sediment were measured, and the effects of roasting temperature, roasting time, and leaching liquid/solid ratio on the extraction of cesium were studied. Almost all of the cesium was extracted under optimal conditions: roasting temperature of 600 °C, roasting time of 3 h, leaching temperature of 25 °C, leaching time of 0.5 h, and liquid/solid ratio of 5:1 mL/g. After the leaching process, the leach liquor with high concentration of cesium of 80.17 g/L was obtained. Finally, the leach liquor was further purified by solvent extraction, and the purity of the cesium chloride product reached 99.66%. Graphical Abstract
研究领域:
化学工程
·
环境科学
✓ 已验证
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
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 26
·19807-19817
·
IF 3.84
Yun Zheng,Xueli Gao,Xinyan Wang,Zhaokui Li,Yuhong Wang,Congjie Gao
In this study, a laboratory-scale electrodialysis (ED) system with an effective area of 88 cm2 was used to remove copper and cyanide in simulated and real gold mine effluents. The membrane fouling was characterized by FTIR, SEM-EDX, membrane resistance measurements and static contact angle. The effects of applied voltage, initial concentration, and flux rate on the removal rate of copper and cyanide were investigated. The highest copper (99.41%) and cyanide (99.83%) removal rates were achieved under the following conditions: applied voltage of 25 V, initial concentration of C2 (concentration of copper and cyanide were 47 mg L−1 and 242 mg L−1), and a flux rate of 4.17 mL s−1. In addition, the lowest concentration of copper (0.44 mg L−1), cyanide (0.48 mg L−1) and zinc (0.34 mg L−1) in the treated effluent were all below regulatory limits (copper, cyanide <0.5 mg L−1, zinc <2.0 mg L−1). The results showed the presence of CuCN, [Cu(CN)3]2−, Cu(OH)2, and Zn(OH)2 in the precipitate, and the fouling of anion-exchange membranes (AEMs) could be decreased significantly via pH adjustment. This research provides a new insight into the removal of copper and cyanide from gold mine effluent.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
AMB Express
·
2018
·Vol. 8
·期 1
·1-8
·
IF 1.719
Guo Yaping,Chang Hui,Wang Qiaoling,Shao Chenjia,Xu Jianmiao
Acrylonitrile (C3H3N) widely used in chemical raw materials has biological toxicity with –CN bond, so it is the key to removal of cyanide from acrylonitrile wastewater. In our previous research and investigation, a strain was identified as Arthrobacter nitroguajacolicus named ZJUTB06-99 and was proved to be capable of degrading acrylonitrile. In this paper, the strain ZJUTB06-99 was domesticated with acrylonitrile-containing medium and its decyanidation and denitrification in simulated acrylonitrile wastewater were studied. The intermediate product of acrylonitrile in degradation process was identified through gas chromatography–mass spectrometer, as well as the biodegradation pathway of acrylonitrile in wastewater was deduced tentatively. The kinetics equation of biodegradation of acrylonitrile was lnC = − 0.1784t + 5.3349, with the degradation half-life of acrylonitrile in wastewater by 3.885 h. The results of this study showed that the optimum levels of temperature, pH and bacteria concentration to attain the maximum biodegradation were obtained as 30 °C, 6 and 100 g/L, respectively. The disadvantages of the biodegradation with this strain and its possible enhanced method to degrade acrylonitrile in wastewater were also discussed.
研究领域:
环境科学
·
微生物学
✓ 已验证
DOI
高影响因子
TETRAHEDRON LETTERS
·
2014
·
IF 2.391
Lianfang Chen,Hongmei Nie,Guangbo Zhang,Fuwen Gong,Yuzhu Yang,Chengbin Gong,Qian Tang,Kun Xiao
This Letter aimed to develop an efficient method for the determination of cyanide ion (CN − ). A novel colorimetric chemosensor 4-[(1 E )-2-(4-hydroxyphenyl)ethenyl]-1-allylpyridinium bromide (HPEAPB) was synthesized. HPEAPB displayed good selectivity toward CN − over other competing anions in ethanol. A color change from yellow to red was immediately observed upon the addition of CN − and the limit of detection (LOD) was 3.4 × 10 −6 mol L −1 . The sensing mechanism was discussed by UV–vis, 1 H NMR titration, and a comparison study. Colorimetric test paper for CN − was prepared by attaching HPEAPB to a chromatography paper , which could be used to detect CN − in environmental samples as simply as a pH-indicator paper for pH value. The LOD of the test paper for CN − was 2.0 × 10 −4 mol L −1 . This detection method for CN − has potential applications in cyanide ion containing fields by combination of rapid and real-time advantages.
研究领域:
分析化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
·
2022
·Vol. 331
·期 6
·2655-2665
·
IF 1.754
Li Tingting,Wang Fang,Xia Liangshu
Uranium, as a highly toxic radioactive contaminant existing in mine wastewater and contaminated groundwater, has sparked widespread alarm in recent years. This work demonstrates the technological possibility of recovering uranium from aqueous solutions using potassium titanium ferrocyanide (KTiFC). The adsorption behavior, kinetics, isotherms, and thermodynamic investigations were systematically examined. The maximum capacities were achieved at pH3.8, and KTiFC was proven to be stable across a wide pH range. The adsorption process was best represented by a pseudo-second order rate equation and the Langmuir isotherm model, with 90% of the uranium eliminated in 60 min. The adsorption process was endothermic and spontaneous, adsorption efficiency of uranium is highly related to water temperature. The integrated analysis of EDS, ICP-OES, FTIR and XPS suggested that chemisorption combined with ion exchange between K and U can describe the adsorption mechanism of uranium sorption on KTiFC. This study points the way toward developing effective and low-cost materials with practical functionality for uranium extraction from polluted water.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2017
·
IF 3.359
Lang Yang,Feifei Jia,Shaoxian Song
The recovery of gold cyanide complex Au(CN) 2 − from gold cyanidation with graphene oxide (GO) and GO hydrogel have been studied to explore the possibility of the application of GO or GO hydrogel in gold cyanidation process for extracting gold. The study was performed on the adsorption of artificial Au(CN) 2 − aqueous solution on GO and GO hydrogel. The adsorption results, as well as the SEM-EDS, AFM and XPS, demonstrated that GO was a better adsorbent for the recovery of Au(CN) 2 − from aqueous solution than conventional activated carbon because of its higher adsorption capacity and adsorption rate. It has been also found that the adsorption of Au(CN) 2 − on GO followed the Langmuir isotherm and fitted well with both the pseudo-first-order and pseudo-second-order kinetics models. The recovery of Au(CN) 2 − with GO might be attributed to the interaction between Au(CN) 2 − and oxygenous function groups on GO surface. GO hydrogel exhibited excellent Au(CN) 2 − adsorption property and easy separation, which enabled it a potential adsorbent in gold cyanidation.
研究领域:
化学工程
·
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）