ACS Sustainable Chemistry & Engineering
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2024
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IF 7.1
Yuanyuan Cai,Zuoren Nie,Xiaoli Xi,Yajiao Zhang,Lu Deng,Zhiyong Zhao,Yingliang Tian
Separation and recovery of molybdenum (Mo) with high concentrations from spent catalysts is a strategy for avoiding the environmental footprint by metal mining and the disposal of hazardous wastes, while alleviating resource shortage. In this paper, a method for constructing a binary (SiO2–Na2O)/ternary (SiO2–Na2O–B2O3) glass phase extraction (GPE) system to selectively extract the impurity metal ions from spent catalysts as well as simultaneously separate and recover Mo is presented. Based on experimental studies and classical molecular dynamics simulations, compared with the binary glass network, 99.4% of Al3+ and Ni2+ in spent catalysts were extracted in a more stable tetra-coordinated form at a lower melting temperature (1200 °C) by the ternary GPE system introducing B2O3, accompanied by Na2MoO4 precipitated as the recovery product. The recovery efficiency of Mo was 98.1%, realizing an efficient separation and short-process recovery. Moreover, the separation of Na2MoO4 melt and glassy liquid during the melting process was visually observed online. Therefore, this approach of constructing glass GPE systems for the one-step separation of metals during the melting process is expected to contribute to the sustainable supply of critical metals.
研究领域:
材料科学
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环境科学
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冶金工程
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
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2025
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IF 7.2
Jingyi Chen,Shuchen Sun,Xuwei Luo,Faxin Xiao,Jing chen,Ziyan Yang,Chengfu Sui,Kuopei Yu,Ganfeng Tu
With the increasing trend of heavy and poor-quality petroleum, hydrotreating of heavy oil has rapidly developed, generating large amounts of spent catalysts. Recovering valuable metals from these catalysts is crucial because of their environmental hazards and scarcity of critical metal. This study developed a recovery method using choline chloride-oxalic acid deep eutectic solvent (DES) to efficiently extract vanadium (V) and molybdenum (Mo) while selectively separating nickel (Ni). Under optimized conditions (ChCl:oxalic acid = 1:2, water-to-DES ratio = 0.3 (v/v), 80 °C, 1:20 g/mL, 3 h), the leaching efficiencies reached 97.8 % for V and 95.1 % for Mo, with only 1.8 % for Ni. Kinetic modeling revealed a two-stage leaching mechanism: surface chemical reaction control initially (0–30 min) transitioning to mixed reaction-diffusion control (30–180 min). The activation energies for V and Mo were 18.08 kJ/mol and 18.93 kJ/mol in the initial stage, and 20.63 kJ/mol and 11.16 kJ/mol in the later stage, respectively. The high efficiency of the DES system originates from the synergistic effects of protonation, reduction, and coordination capabilities. Selective separation of Ni was achieved by forming insoluble nickel oxalate dihydrate (NiC₂O₄·2H₂O), while the alumina carrier (Al₂O₃) remained intact. These mechanisms ensure high efficiency and strong selectivity of the multimetal leaching system. This work is the first to demonstrate a highly selective DES-based approach for simultaneous efficient extraction of V and Mo with effective separation of Ni from spent hydrotreating catalysts under mild conditions, providing significant environmental benefits and a sustainable recovery strategy.
研究领域:
环境科学
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
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2022
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IF 7.968
Bo Wang,Qiaowen Yang
Large amounts of spent selective catalytic reduction (SCR) catalysts were produced in industry after losing their activity. This study developed a clean and effective route of leaching and recovery of vanadium (V) from spent SCR catalyst. First, ascorbic acid (C 6 H 8 O 6 ) as the adjuvant can enhance vanadium leaching in H 2 SO 4 solution. The effect parameters of acid concentration, leaching temperature, leaching time and liquid-solid (L/S) ratio on the leaching efficiency of vanadium were investigated. Then, the enrichment of vanadium in the leachate to obtain the black cake was carried out through adjusting pH value. The effects of vanadium concentration and pH on the precipitation efficiency of vanadium were studied. Finally, after alkaline dissolution and oxidation of the black cake, ammonium chloride (NH 4 Cl) was selected and used as the precipitant to obtain the ammonium poly-vanadate (APV). The final product vanadium pentoxide (V 2 O 5 ) was obtained through roasting APV at 550 ℃ for 1.0 h. The black cake, APV and V 2 O 5 were analyzed by the characterization of XRD or XRF . This study may introduce a new perspective for the effective usage of vanadium from spent SCR catalyst.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
Metals
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2021
·Vol. 11
·期 6
·919
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IF 2.351
Feng Feng,Jiamei Liu,Mingxing Zhao,Lu Yu,Haixin Wang,Chunshan Lu,Qunfeng Zhang,Jia Zhao,Yanxia Sun,Jie Cen,Xiaonian Li
Gold as a precious metal resource has high recycling significance. However, the current extraction methods cannot achieve the both efficiency and environmental friendliness. In this paper, we propose a new gold leaching agent, which can leach gold under light condition by mixing iodoform (CHI3) with 1-butyl-3-methylimidazolium dicyanamide (BmimN(CN)2) ionic liquid. Under 25 °C and 13 W incandescent lamp irradiation, the leaching yield of gold can achieve 100 wt%, and the average leaching rate is 945 mg Au/(h·mol·CHI3) (18.9 times of that of the cyanidation method). Through the analysis of the results of radical inhibition experiment, UV-Vis and XPS, a possible leaching mechanism is proposed: the iodine radical generated by light oxidizes Au0to Au+, and then forms AuN(CN)2by coordinating with N(CN)2−. Subsequently, the ionic liquid and Au N(CN)2form a stable [Bmim]·[Au(N(CN)2)2] ion pair structure, further promoting the dissolution reaction. The leaching yield of gold can reach 81.9 wt% and 100 wt%, respectively, when applied to ore and waste electrical and electronic equipment (WEEE); the leaching yield of gold can also reach 100 wt% when applied to a waste catalyst by adding a Soxhlet extraction. The results show that this method is not only efficient, mild, and environmentally friendly, but also has strong adaptability and wide application prospects.Keywords:gold recovery;ionic liquid;free radical;waste catalyst;oxidation-complexation
研究领域:
化学
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环境科学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2023
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IF 15.1
Yuanyuan Cai,Zuoren Nie,Xiaoli Xi,Yue Lu,Yajiao Zhang,Guoyu Huang,Caijuan Shi,Lu Deng,Zhiyong Zhao,Yingliang Tian
Spent hydrofining/selective catalytic reduction catalysts generated during the production of ultra-low-sulfur/nitrogen fuel are considered to be hazardous wastes . Furthermore, the sustainable supply of critical metal resources such as molybdenum (Mo), tungsten (W), nickel (Ni) and vanadium (V), which are present in high concentrations in spent catalysts, is challenged by the climate emergency, ore depletion and inefficient technologies for separating metals. Here, glass phase extraction is proposed as a novel approach for simultaneously separating metals and obtaining recovered products from spent hydrofining catalysts in one step. By constructing a glass network structure that satisfied a stable coordination environment for the target metal ions , 99.82 % of the Mo 6+ was “melt-melt” separated with the glass phase as Na 2 MoO 4 , while the extraction efficiencies of Ni 2+ and Al 3+ were >99.16 %. The separation factors β Mo/Ni and β Mo/Al were as high as 65812.95 and 71944.85, respectively. The obtained results verify this method as a valuable synthetic route for refractory metal salts and transition metal ion-doped glass–ceramic materials, enhancing the prospect of achieving full-component resource recovery from hazardous wastes.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
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2021
·
IF 9.297
Ruobing Zhang,Yimin Zhang,Tao Liu,Qian Wan,Dalong Zheng
In recent years, the use of spent fluid catalytic cracking (SFCC) catalysts to prepare geopolymers has received attention from academic and industrial circles. However, SFCC catalysts have been classified as hazardous waste in China due to their vanadium and nickel content. In this paper, the immobilization rates of vanadium and nickel in geopolymers prepared with SFCC catalysts were studied through a toxicity characteristic leaching procedure (TCLP). The immobilization mechanism of nickel and vanadium during geopolymerization was investigated by XPS, SEM, XRD , and compressive strength measurements. The nickel and vanadium TCLP concentrations of the SFCC catalyst-based geopolymer are 0.032 mg/L and 10.63 mg/L, respectively. Nickel in the SFCC catalyst is partly dissolved and adsorbed by the negatively charged tetrahedral aluminum in the geopolymer. However, because vanadates formed under alkaline conditions are negatively charged and readily soluble in water, vanadium in the SFCC catalyst is neither immobilized by the charge balance nor effectively immobilized by physical encapsulation. Therefore, the use of SFCC catalysts to prepare geopolymers will lead to vanadium contamination in the environment. In order to clarify the maximum vanadium content in SFCC catalysts for preparing geopolymers without environmental risk, SFCC catalysts with different vanadium levels were prepared by leaching. It was concluded that when the vanadium content in the SFCC catalyst is lower than 1861.4 mg/kg, the vanadium content in the leachate is lower than 2 mg/L and the geopolymer can be considered a non-hazardous material.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
高影响因子
Recycling
·
2025
·Vol. 10
·期 1
·10
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IF 4.6
Xin Hong,Jingyi Chen,Jing Wei,Wenjie Wu,Ziyan Yang,Jing Chen,Shuchen Sun,Faxin Xiao,Ganfeng Tu
As environmental awareness grows, hydrodesulfurization (HDS) catalysts have become crucial in petroleum refining, yet their use results in oil-laden waste, poses environmental risks, and complicates subsequent treatment. Efficient oil removal is thus critical for processing spent catalysts. This study systematically compares three de-oiling methods, extraction, chemical thermal washing, and pyrolysis, to identify the optimal de-oiling method. In the experiments, extraction achieves a 94.12% oil removal rate at a liquid-to-solid ratio of 10 mL/g, a temperature of 45 °C, and a time of 60 min, maintaining around 90% efficiency after five cycles of solvent recovery. Chemical thermal washing achieves an oil removal rate of 96.26% after 4 h at 90 °C, with 0.15 wt.% SDS, 3.0 wt.% NaOH, and a liquid-to-solid ratio of 10 mL/g. The heavy oil emulsion is then decomposed with 4% CuO and 5% H2O2. The pyrolysis method removes 96.19% of oil at 600 °C in 60 min. While the extraction and chemical thermal washing methods are effective, they produce wastewater, raising environmental concerns. In contrast, the pyrolysis method is more environmentally friendly. SEM, EDS, and FT-IR analyses show that after oil removal, the metal structures on the alumina support of the spent HDS catalyst are clearly exposed, facilitating the subsequent recovery of valuable metals.
研究领域:
化学工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2024
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IF 12.2
Maolin Tian,Hongtao Liu,Jian Cui,Yaqing Weng,Xueli Wang,Erkang Feng,Wenjie Zhang,Caifang Cao,Jiawei Wen,Guoyong Huang,Shengming Xu
The removal of crude oil from spent hydrodesulfurization catalysts constitutes the preliminary stage in the recovery process of valuable metals. However, the traditional roasting method for the removal exhibits massive limitations. In view of this, the present study used an ultrasound-assisted surfactant cleaning method to remove crude oil from spent hydrodesulfurization catalysts, which demonstrated effectiveness. Furthermore, the study investigated the mechanism governing the process with calculation and experiments, so as to provide a comprehensive understanding of the cleaning method’s efficacy. The surfactant selection was predicated on the performance in the IFT test, with SDBS and TX-100 finally being chosen. Subsequent calculations and analysis were then conducted to elucidate their frontier molecular orbitals , electrostatic potential , and polarity. It has been found that both SDBS and TX-100 possess the smallest LUMO-HOMO energy gap (ΔE), registering at 4.91 eV and 4.80 eV, respectively, and presenting the highest interfacial reactivity. The hydrophilic structure in the surfactant regulates the wettability of the oil-water interface, and the long-chain alkanes have excellent non-polar properties that promote the dissolution of crude oil. The ultrasonic-assisted process further improves the interface properties and enhances the oil removal effect. Surprisingly, the crude oil residue was reduced to 0.25% under optimal conditions. The final phase entailed the techno-economic evaluation of the entire process, revealing that, in comparison to the roasting method, this process saves $0.38 per kilogram of spent HDS catalyst, with the advantages of operational simplicity and emission-free. Generally, this study shed new light on the realization of efficient oil removal, with the salience of green, sustainable, and economical.
研究领域:
化学工程
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环境科学
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催化材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
HYDROMETALLURGY
·
2023
·
IF 4.7
Shaoping Feng,Kun Huang
Dialkylsulfide is considered as the most promising extractant for separating Pd(II) and Pt(IV) in industrial processes. However, the slow kinetics for Pd(II) extraction limits its extensive application. The development of new extractants with faster kinetics, high extraction efficiency, and exceptional Pd(II) separation selectivity has been a persisting goal over the past few decades. In this study, a new functionalized extractant, 1-methyl-2-(nonylthio)-1H-imidazole (MNI) containing both N and S atoms, was synthesized and employed to separate Pd(II) from mixed hydrochloric acid solutions with different initial Pd(II)/Pt(IV) concentration ratios. Experimental results revealed that MNI not only has a high selectivity for Pd(II) over Pt(IV) but also has faster kinetics for Pd(II) extraction than diisopentylsulfide (S201) under similar extraction conditions. In contrast to traditional dialkylsulfide extractants, MNI coordinates with Pd(II) ions via the N(5) atom in its imidazole ring to form Pd(MNI) 2 Cl 2 complexes, instead of using the S atom as with dialkylsulfide. The extraction mechanism involving the coordination between Pd(II) and MNI was demonstrated using the slope analysis method and ultraviolet (UV), Fourier-transform infrared (FT-IR), 1 H NMR, and 13 C NMR spectroscopic methods. The fast extraction kinetics between MNI and Pd(II) was possibly attributed to the high charge density of the N(5) atom in the imidazole ring, whereas the outstanding separation selectivity for Pd(II) was due to the strong affinity of the N(5) atom. The facile synthesis, high saturation capacity, excellent Pd(II) selectivity, and remarkable reusability endow MNI with potential applications in Pd(II) recovery from leach solutions of waste automotive catalysts and other secondary resources.
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
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Haoran Yu,Shuo Liu,Ali Yaraş,Linchao Hu,Wenyi Zhang,Mingguo Peng,Hasan Arslanoğlu,Qingqing Huang,Bolormaa Oyuntsetseg,Bingying Gao,Linqiang Mao
Spent hydrodesulfurization (HDS) catalyst contains considerable amounts of Mo, Ni and V, is an important secondary resource for these valuable metals. Direct acid solution leaching method exhibits poor separation effect from catalyst carrier for Mo due to greater stability of MoS 2 . This study explored Mo leaching efficiencies from spent HDS catalyst by Fenton-like oxidation systems (H 2 O 2 and K 2 S 2 O 8 ), which were frequently employed in the wastewater treatment. To further improve Mo leaching efficiency, nano zero-valent iron (nZVFe) was used to activate H 2 O 2 /K 2 S 2 O 8 and produce more free radicals (·OH and ·SO 4 - ). Approximate 96.0 % and 93.3 % of Mo were leached from spent HDS catalyst in nZVFe + H 2 O 2 + H 2 SO 4 and nZVFe + K 2 S 2 O 8 + H 2 SO 4 systems under optimal experimental conditions, increased by 16.2 % and 8.2 % than normal H 2 O 2 (79.8 %) and K 2 S 2 O 8 (85.1 %) system without nZVFe. The leaching process of Mo in both nZVFe + H 2 O 2 + H 2 SO 4 and nZVFe + K 2 S 2 O 8 + H 2 SO 4 systems conformed to the shrinkage core model. Kinetic analysis and molecular calculation demonstrated the leaching process of Mo in nZVFe + H 2 O 2 + H 2 SO 4 system was driven by chemical reaction and solid film diffusion, and the leaching and oxidation reactions of MoS 2 occurred simultaneously. However, the leaching process of Mo in nZVFe + K 2 S 2 O 8 + H 2 SO 4 system was driven only by chemical reaction, solid MoS 2 was firstly dissolved into Mo 4+ by H + , and then oxidized into Mo 6+ by ·SO 4 - . The economic and environmental impacts evaluation indicated that the separation of Mo from spent HDS catalysts by nZVFe + H 2 O 2 + H 2 SO 4 was assigned as a better choice than normal H 2 O 2 and K 2 S 2 O 8 system without nZVFe due to higher leaching efficiency and lower cost.
研究领域:
化学工程
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环境科学
✓ 已验证
DOI
高影响因子
Journal of Cleaner Production
·
2025
·
IF 10
Qianyuan Zhang,Qihui Wang,Chunli Li,Pinggui Tang,Yongjun Feng
Addressing the challenges of simultaneously extracting Pd and Ag components from spent acetylene hydrogenation catalysts, severe structural damage to the Al 2 O 3 supports, and high wastewater discharge, here, we propose a “hydrochloric acid–ammonium chloride–ammonia” (HCl–NH 4 Cl–NH 3 ) complexation system that enables efficient extraction of PdAg leaching alongside recovery of the Al 2 O 3 supports. The leaching rates of Pd and Ag exhibit an increasing trend with rising concentrations of HCl, NH 4 Cl, and NH 3 , the increase of reaction temperature, and the extension of reaction time. Nevertheless, excessively high HCl concentration, overly elevated reaction temperature, and unduly prolonged reaction time caused some damage to the structure of the alumina support and reduce its mechanical strength. Under optimized conditions (0.2 M HCl, 1.0 M NH 4 Cl, 120 °C, 6 h, 5 wt% ammonia), the PdAg components were efficiently leached while effectively preserving the crystal phase and pore structure of the Al 2 O 3 beads. The leaching rates of Pd and Ag reached 95.6 % and 94.4 %, respectively; and the recovered Al 2 O 3 beads have a pore diameter of 30.8 nm, a specific pore volume of 0.244 mL g −1 , a specific surface area of 29.2 m 2 /g, and a crushing strength of 53.2 N, corresponding to retention rates of 95.2 %, 96.0 %, 100.2 %, and 98.6 %, respectively. The HCl–NH 4 Cl–NH 3 complexation system, combined with cyclic washing, shows advantages of low cost, mild extraction conditions, and reduced wastewater discharge, which keeps to the principles of green development.
研究领域:
环境化学
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资源循环利用
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工业催化
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材料回收
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绿色化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2025
·
IF 7.3
Jiawei Wen,Lin Li,Changjin Liu,Hongtao Liu,Dongyue Zhao,Guoyong Huang,Shengming Xu
Converting spent aluminum-based catalysts into novel CO2 methanation catalysts represents a promising strategy for simultaneous waste valorization and greenhouse gas mitigation. However, achieving a high-value utilization of spent catalysts and efficient low-temperature CO2 methanation remains a significant challenge. This study reports the synthesis of high-performance carbon sequestration Ni-M/Al2O3 catalysts (M = Mn, Mo, Co, V) with high CO2 conversion and CH4 selectivity, derived from regenerated γ-phase alumina (γ-Al2O3) support obtained from spent catalysts. The associated active metals were recovered through selective leaching and subsequently incorporated via wet impregnation. Catalytic performance was evaluated in a fixed-bed reactor under atmospheric pressure, with the 20 wt % Ni-1 wt % V catalyst demonstrating optimal activity at 300 °C, achieving 92.95% CO2 conversion and CH4 yield peak. Mechanistic investigations revealed that V doping induces HCO* co-intermediates formation and shifts the reaction pathway from reverse water–gas shift to formate route, thereby reducing the rate-determining step barrier and facilitating methanation. This study establishes an effective green and sustainable approach for spent catalyst valorization while providing fundamental insights into V-promoted low-temperature CO2 methanation, offering significant implications for carbon reduction and energy transition technologies.
研究领域:
催化化学
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环境科学
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化学工程
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材料科学
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碳捕集与利用（CCU）
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绿色化学
✓ 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）