Metals
·
2025
·Vol. 15
·期 5
·468
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IF 2.5
Shuo Tian,Jing Song,Hongqian Sun,Congcong Zhao,Zhiyu Zhang,Mingming Han,Tao Qi
Zirconium (Zr) and hafnium (Hf) are very important in nuclear and high-temperature applications, but their similar physical and chemical properties bring great challenges to separation. The current extraction methods have defects, such as low efficiency at high metal concentration. In this article, a zirconium (Zr)/hafnium (Hf) solvent extractive separation from sulfuric acid solutions using trioctylamine (TOA) as the extractant was researched at room temperature. The aqueous solution is prepared using zirconium sulfate (containing Hf), and the concentration of metal ions (Zr4+and Hf4+) was about 1.096 mol·L−1. The effects of the aqueous acidity, the concentration of TOA, the contacting time, and the organic to aqueous O/A ratio on the separation of Zr and Hf were investigated. It is observed that the Zr can be extracted in the organic phase selectively, and the optimal conditions were: TOA concentration of 40 vol%, organic to aqueous O/A ratio of 3, contacting time of 5 min. Under these conditions, the single-stage extraction rate of Zr is 61.23%, while the Hf is almost not extracted. The mechanism of Zr extraction by TOA was studied through the saturation capacity and slope methods. Based on the results, it is believed that the structure of the extracted complex may be [R3NH]2[Zr(SO4)3]. This study provides a new approach for the development of industrialized Zr-Hf separation.
研究领域:
化学工程
·
核工业
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DOI
高影响因子
MINERALS ENGINEERING
·
2022
·
IF 5.479
Xiaoge Wang,Binchuan Li,Jianshe Chen,Shuang Cui,Kuiren Liu,Xiaocai He,Qing Han
This study develops an efficient technique to purify the highly concentrated cyanide-containing industrial wastewater by recovering the valuable components. Firstly, sodium sulfide, sodium polysulfide and ferrous sulfate were respectively used as the precipitating agents to retrieve zinc, copper and iron from wastewater stepwise. In the meantime, cyanide presented as free cyanide and copper–cyanide complexes were transformed into thiocyanate by polysulfide . Afterwards, the solvent extraction of thiocyanate was systematically conducted with trioctylamine (TOA) as the extraction agent and sodium hydroxide solution as the stripping agent. The results showed that the contents of zinc, copper and iron in the solution after precipitation were less than 1 mg·L −1 . Focusing on the reaction between copper–cyanide complex and polysulfide , three stages were established for the first time. In the first stage, Cu(CN) 3 2− was gradually converted to CuCN 0 and thiocyanate was rapidly generated. In the second stage, in addition to the formation of thiocyanate, Cu(I) was oxidized by polysulfide and precipitated as CuS ultimately. With an apparent activation energy of 70.9 kJ∙mol −1 , kinetic analysis of the second stage suggested a significant effect of temperature on the copper–cyanide complex conversion rate. The apparent reaction orders of zero-valent sulfur and cyanide was 1.34 and 2.33, respectively. After the extraction and stripping process, the extraction efficiency of thiocyanate was nearly 100 % and the concentration of it can be enriched to 125 g·L −1 in the stripping solution. TOA and thiocyanic acid formed an extraction complex in a 1:1 ratio. This approach achieves the simultaneous recovery of valuable metallic ions (zinc, copper and iron) and cyanide conversion under the alkaline condition, which provides a new idea for the treatment of highly concentrated cyanide-containing wastewater with a complicated composition.
研究领域:
环境科学
·
化学工程
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DOI
高影响因子
Journal of Cleaner Production
·
2018
·
IF 5.651
Hengjun Gai,Caiyun Zhong,Lin Qiao,Shuo Chen,Meng Xiao,Hongbing Song
Wastewater containing 1-amino-2-naphthol-4-sulfonic acid (ANS) is mainly derived from the dye production process, causing serious environmental problems. In this work, extraction of ANS from wastewater was carried out using trioctylamine (TOA) under condition of methyl isobutyl ketone (MIBK) as a diluent. The effects of diluent type, concentration of TOA, temperature and pH on the distribution coefficient (D) were discussed in detail. The results showed that the value of D = 76 was obtained with TOA (1.41 mol kg −1 ) + MIBK at 25 °C and pH = 1.1. After that, the extraction mechanism was determined by analyzing the chemical bonds of the complex compound using UV–vis, FT-IR and 1 H NMR. The experimental results showed that the extractant could be regenerated by back extraction. Specially the distillation process was simulated using Aspen Plus and the results verified its feasibility in the process of extractant regeneration. The proposed extraction system is conductive to both environment and technology .
研究领域:
环境科学
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化学工程
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产品关联
DOI
高影响因子
International Journal of Minerals Metallurgy and Materials
·
2023
·Vol. 30
·期 5
·877-885
·
IF 4.8
Wang Junlian,Liu Lu,Xu Wen,Liu Hui,Xu Guodong,Huang Kun,Yu Fengshan,Huang Guoyong
Platinum group metals (PGMs), especially Pd, Pt, and Rh, have drawn great attention due to their unique features. Direct separation of Pd and Pt from highly acidic automobile catalyst leach liquors is disturbed by various factors. This work investigates the effect of various parameters including the acidity, extractant concentration, phase ratio A/O, and diluents on the Pd and Pt extraction and their stripping behaviors. The results show that the Pd and Pt are successfully separated from simulated leach liquor of spent automobile catalysts with monothio-Cyanex 272 and trioctylamine (TOA). Monothio-Cyanex 272 shows strong extractability and specific selectivity for Pd, and only one single stage is needed to recover more than 99.9% of Pd, leaving behind all the Pt, Rh, and base metals of Fe, Mg, Ce, Ni, Cu, and Co in the raffinate. The loaded Pd is efficiently stripped by acidic thiourea solutions. TOA shows strong extractability for Pt and Fe at acidity of 6 mol·L −1 HCl. More than 99.9% of Pt and all of the Fe are extracted into the organic phase after two stages of countercurrent extraction. Diluted HCl easily scrubs the loaded base metals (Fe, Cu, and Co). The loaded Pt is efficiently stripped by 1.0 mol·L −1 thiourea and 0.05–0.1 mol·L −1 NaOH solutions. Monothio-Cyanex 272 and TOA can realize the separation of Pd and Pt from highly acidic leach liquor of spent automobile catalysts.
研究领域:
冶金学
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化学工程
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环境科学
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DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Long Yao,Guixuan Shan,Abrar Laiba,Yu Zhao,Yujiao Zhang,Ru’an Chi,Bingwen Long,Wei Li,Jinli Zhang
Fluorine (F) is a valuable by-product in wet-process phosphoric acid (WPA) production, yet its recovery ratio remains below 60 % due to challenges in purification and utilization. Traditional stripping methods release toxic and corrosive fluorine vapors, endangering production safety. Herein, a novel strategy of Fluoride Species Conversion-Enhanced Selective Extraction (FSC-SE) was put forward for the efficient and environmentally friendly recovery of fluorine from wet process phosphoric acid (WPA). By converting HF and H 2 SiF 6 into HBF 4 through the addition of boric acid, the extraction efficiency of fluorine is significantly enhanced, reaching up to 99.8 % using trioctylamine (TOA) as the extractant. Theoretical calculations were carried out to provide a predictive framework for the extraction selectivity of TOA for different acidic species. Key operation parameters, including B:F molar ratio, TOA concentration, extraction time, and temperature, etc, are, optimized to further enhance the process performance. Subsequent water washing and back-extraction steps enabled effective P-F separation and extractant regeneration. Applied to industrial WPA, the single-stage fluorine extraction efficiency can reach 82.4 %, and the total fluorine recovery ratio can reach 80.4 %. FSC-SE provides a safe, efficient, and environmentally friendly method with strong industrial application potential, highlighting the value of the green separation process combining chemical conversion and solvent extraction in the phosphoric acid industry.
研究领域:
化学工程
·
湿法冶金
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绿色化学
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资源回收
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分离科学
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DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2019
·Vol. 93
·期 2
·391-401
·
IF 1.986
Yi Huilin,Wan Yanchun,Zhang Yang,Wang Yujun,Fei Weiyang,Luo Guangsheng
This study describes a novel and facile route for fabricating highly uniform γ-alumina microspheres with controllable size, morphology, and pore structure by integrating the sol–gel route for alkoxide with “temperature/pH-induced gelation” in a coaxial microchannel. Taking advantage of the controllability of the microfluidic devices and Al–O–Al chains formed by the sol–gel route of aluminum alkoxide, the uniformity of the microspheres was assured, and the mechanical strength of the microspheres was greatly improved to 18–27 N/mm 2 . The effects of the continuous phase composition and two-phase flow rate on the size, morphology, and pore structure of the obtained microspheres were investigated. When triocylamine (TOA) was added to the continuous phase and the two-phase flow rate ratio was larger than 188, the as-prepared microspheres had a smooth surface and good sphericity; otherwise, the microspheres had poor spheriticy and included many ravines on the surface, which can be explained by the mutual influence of long-lasting movements of molecular chains resulted from low gelation speed and inner circulation of the droplets. Under different continuous phase compositions, the average pore diameter, pore volume, and specific surface area ranged from 7 to 12 nm, 0.89 to 1.58 mL/g, and 293.7 to 387.7 m 2 /g, respectively.
研究领域:
材料科学
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化学工程
·
微流控技术
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产品关联
DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2024
·
IF 4.5
Huihui Xie,Han Xia,Zihan Qin,Zaichao Dong,Xin Wang,Liang Sun,Yang Liu,Yang Zhang
Polymer inclusion membranes (PIMs) exhibit great potential in the separation and recovery of valuable materials from wastewater and secondary resources. In this work the effect of alkyl chain configuration of the functional carriers on the physicochemical properties and permeability of PIMs was investigated. Three tertiary amine isomers with different alkyl chain configurations were selected as carriers: trioctylamine, triisooctylamine, and tris(2-ethylhexyl)amine. Operating conditions like carrier contents, feed solution pH, phenol concentration, and stripping solution properties were also investigated. The results obtained in this study indicate that tertiary amines with less branched alkyl chains perform better phenol transport efficiency. Furthermore, the transport efficiency decreased rapidly with increasing steric hindrance of the carriers. Trioctylamine-based PIM displayed optimal extraction efficiency of 92.8 % and stripping efficiency of 90.8 % due to its lower steric hindrance, higher hydrophilicity, and larger crystallinity. Phenol extraction and stripping efficiencies remained above 85.7 % and 80.8 % after 8 cycles, demonstrating excellent stability.
研究领域:
环境科学
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化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）