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Atmospheric reductive catalytic fractionation of lignocellulose integrated with one-pot catalytic conversion of carbohydrate yielding valuable lignin monomers and platform chemicals from corn straw 被引量:2
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作者 Meng-Ying Liu Zhe-Hui Zhang +7 位作者 Xue-Qi Wang Qian Sun Chen Zhang Yu Li Zhuohua Sun Katalin Barta Feng Peng Tong-Qi Yuan 《Green Energy & Environment》 SCIE EI CAS 2025年第1期161-172,共12页
Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent years.Herein,taking advantage of the“lignin f... Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent years.Herein,taking advantage of the“lignin first”strategy,corn straw is converted to valuable chemicals including lignin monomers,furfural and 5-methoxymethylfurfural via a two steps process.The key of this research lies in the development of a green and low-cost catalytic process utilizing magnetic Raney Ni catalyst and high boiling point ethylene glycol.The utilization of neat ethylene glycol as the sole slovent under atmospheric conditions obviates the need for additional additives,thereby facilitating the entire process to be conducted in glass flasks and rendering it highly convenient for scaling up.In the initial step,depolymerization of corn straw lignin resulted in a monomer yield of 18.1 wt%.Subsequently,in a dimethyl carbonate system,the carbohydrate component underwent complete conversion in a one-pot process,yielding furfural and 5-methoxymethylfurfural as the primary products with an impressive yield of 47.7%. 展开更多
关键词 Atmospheric reductive catalytic fractionation Corn straw Ethylene glycol Raney Ni 5-Methoxymethylfurfural
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Photoinduced Nickel-Catalyzed Reductive Heck Reaction
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作者 Liu Junjie Zhao Hongping +2 位作者 Hu Yuanyuan Wang Hengxin Yuan Weiming 《有机化学》 北大核心 2025年第5期1691-1697,共7页
An efficient visible-light induced nickel-catalyzed reductive Heck reaction of alkenes by using mild organic reductant Hantzsch ester(HEH)instead of traditional metal reductants or hydride reagents was developed.The r... An efficient visible-light induced nickel-catalyzed reductive Heck reaction of alkenes by using mild organic reductant Hantzsch ester(HEH)instead of traditional metal reductants or hydride reagents was developed.The reductive hydroarylation of acrylates with aryl halides was successfully achieved without requiring exogenous photoredox catalysts.This reaction is highlighted by the simple and mild conditions,good functional group tolerance,thus providing a complementary approach for alkenes reductive Heck reaction. 展开更多
关键词 NICKEL reductive Heck reaction visible light organic reductant alken
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Effects of reductive soil disinfestation on potential pathogens and antibiotic resistance genes in soil 被引量:2
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作者 Huijuan Duan Yue Yin +5 位作者 Yifei Wang Zhelun Liu Tiangui Cai Dong Zhu Chun Chen Guilan Duan 《Journal of Environmental Sciences》 2025年第4期373-384,共12页
Reductive soil disinfestation(RSD)is commonly employed for soil remediation in greenhouse cultivation.However,its influence on antibiotic resistance genes(ARGs)in soil remains uncertain.This study investigated the dyn... Reductive soil disinfestation(RSD)is commonly employed for soil remediation in greenhouse cultivation.However,its influence on antibiotic resistance genes(ARGs)in soil remains uncertain.This study investigated the dynamic changes in soil communities,potential bacterial pathogens,and ARG profiles under various organicmaterial treatments during RSD,including distillers’grains,potato peel,peanut vine,and peanut vine combined with charcoal.Results revealed that applying diverse organic materials in RSD significantly altered bacterial community composition and diminished the relative abundance of potential bacterial pathogens(P<0.05).The relative abundance of high-risk ARGs decreased by 10.7%-30.6%after RSD treatments,the main decreased ARG subtypeswere AAC(3)_Via,dfrA1,ErmB,lnuB,aadA.Actinobacteria was the primary host of ARGs and was suppressed by RSD.Soil physicochemical properties,such as total nitrogen,soil pH,total carbon,were crucial factors affecting ARG profiles.Our findings demonstrated that RSD treatment inhibited pathogenic bacteria and could be an option for reducing high-risk ARG proliferation in soil. 展开更多
关键词 reductive soil disinfestation(RSD) Antibiotic resistance genes(ARGs) Bacterial communities Farmland soil Potential pathogens
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Cr-Catalyzed Reductive Cross-Coupling of Trifluoromethyl Alkenes
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作者 Xu Wen Luo Meiming Zeng Xiaoming 《有机化学》 北大核心 2025年第9期3401-3411,共11页
A chromium(II)-catalyzed reduction cross coupling reaction was reported.This reaction utilizes inexpensive and readily available chromium dichloride as a catalyst and 4,4'-di-tert-butyl-bipyridine as a ligand to a... A chromium(II)-catalyzed reduction cross coupling reaction was reported.This reaction utilizes inexpensive and readily available chromium dichloride as a catalyst and 4,4'-di-tert-butyl-bipyridine as a ligand to achieve reduction cross coupling between trifluoromethyl olefins and alkyl bromides under mild conditions,effectively synthesizing difluoroalkene derivatives.This reaction exhibits good substrate universality and is compatible with multiple important functional groups,providing a concise synthetic pathway for constructing conjugated difluoroalkenes containing allyl difluoromethylene structural units.Preliminary mechanistic experiments indicate that alkyl bromides first undergo a reduction process to generate corresponding alkyl radicals,followed by addition to trifluoromethyl olefins.After binding with Cr(II),they undergo aβ-fluorine elimination process to generate difluoroalkenes. 展开更多
关键词 chromium catalysis gem-difluoroalkene reductive cross-coupling
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Ni-Catalyzed Reductive Alkylation of Polyfluoroarenes with Alkyl Halides
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作者 Xie Shentong Li Wenjing +2 位作者 Liu Yu Lu Xi Shi Renyi 《有机化学》 北大核心 2025年第6期2121-2127,共7页
Polyfluoroarenes represent an essential group of compounds in the fields of medical and material chemistry.It is still a challenge to synthesize alkylated polyfluoroarenes.Herein,a Ni-catalyzed reductive alkylation of... Polyfluoroarenes represent an essential group of compounds in the fields of medical and material chemistry.It is still a challenge to synthesize alkylated polyfluoroarenes.Herein,a Ni-catalyzed reductive alkylation of polyfluoroarenes with alkyl halides under mild conditions is reported.Polyfluoroarenes(3~6 F)can reacted smoothly with a diverse range of alkyl halides,such as primary,secondary,and tertiary alkyl iodides.The efficient formation of C(sp2)—C(sp3)can be achieved through the combination of Ni catalysis and(Bpin)2/K2CO3 as terminal reductant. 展开更多
关键词 nickel catalysis polyfluoroarenes alkyl halides reductive cross-coupling
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Generation of carbon dioxide anion radical by UV/small molecular monocarboxylic acid system for reductive dechlorination of chlorinated alkanes
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作者 Li-Zhi Huang Jingjing Lin +4 位作者 Weiguo Chen WeiWang Yitao Dai Ivan P.Pozdnyakov Bingbing Hu 《Journal of Environmental Sciences》 2025年第12期50-59,共10页
The persistence of chlorinated alkanes in aquatic environments poses significant health risks due to its biotoxicity and high volatility,which contributes to both water and air pollution.This study investigates the ef... The persistence of chlorinated alkanes in aquatic environments poses significant health risks due to its biotoxicity and high volatility,which contributes to both water and air pollution.This study investigates the efficacy of carbon dioxide radical anion(CO_(2)·^(-))mediated advanced reduction processes(ARPs)for the reductive dechlorination of chlorinated alkanes using small molecular monocarboxylic acids(SMAs)under UV irradiation.The study focused on formic acid(HCOOH),acetic acid(CH_3COOH),and propionic acid(CH_3CH_(2)COOH)to generate CO_(2)·^(-),revealing that UV/HCOOH system exhibits a notably high chloroform(CF)degradation efficiency of 97.8%in 90 min.Kinetic studies indicated a linear relationship between the HCOOH concentrations and the observed reaction rate constants(k_(obs)),demonstrating that CO_(2)·^(-)production is crucial for CF degradation.Electron paramagnetic resonance spectroscopy identified CO_(2)·^(-)and hydroxyl radicals(HO·)as the active species,with the former playing a predominant role in CF degradation.The study also explored the influence of carbon chain length in SMAs on CF degradation,finding that longer chains decrease the degradation efficiency,potentially due to reduced UV activation.A higher reaction rate constant(k_(obs))under acidic conditions,with a marked decrease in efficiency as the pH exceeds 3.7,where HCOO^(-)becomes predominant.This study enhances our understanding of CO_(2)·^(-)mediated ARPs and explores potential applications in environmental remediation,providing insights into the pathways and mechanisms of CF degradation.The UV/SMAs systems offer advantages for practical applications,such as milder reaction conditions and higher efficiency compared to traditional methods. 展开更多
关键词 CHLOROFORM reductive dechlorination Carbon dioxide radical anion Advanced reduction processes UV photolysis
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Thermodynamic properties and reaction mechanism of coal reductive decomposition phosphogypsum to prepare CaO and SO_(2)
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作者 Pengxing Yuan Meng Li +1 位作者 Shiyi Chen Wenguo Xiang 《Chinese Journal of Chemical Engineering》 2025年第3期135-144,共10页
The thermal effects,spontaneity and proceeding degree of 32 chemical reactions during coal reductive decomposition phosphogypsum(PG)to prepare CaO and SO_(2)are analyzed utilizing thermodynamic theory and method.The i... The thermal effects,spontaneity and proceeding degree of 32 chemical reactions during coal reductive decomposition phosphogypsum(PG)to prepare CaO and SO_(2)are analyzed utilizing thermodynamic theory and method.The ideal reaction temperature for PG decomposition and desulfurization is 1173-1273 K.The 10 key chemical reactions controlling coal reductive decomposition PG have been selected.The heat release of critical exothermic reactions can satisfy the autothermal operation of PG decomposition and desulfurization process.Meanwhile,the spontaneity of oxidation reactions has thermodynamically priority over reduction reactions.But the reaction mechanism shows that the oxidation of CaS by O_(2)is in parallel competition with the reduction of CaSO_(4)by CO and C.Furthermore,clarifying the regulatory mechanisms of PG decomposition temperature and reaction atmosphere(reducibility and oxidation)is beneficial for maximizing the production of CaO and SO_(2). 展开更多
关键词 PHOSPHOGYPSUM COAL THERMODYNAMIC reductive decompositio
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Na_(2)SO_(4)-assisted reductive roasting for enhanced Ni and Co recovery from limonitic laterite:Mechanism and pilot-scale rotary kiln validation
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作者 Jing Chen Yuqi Zhong +5 位作者 Boqi Wang Jun Luo Zhiwei Peng Yanhu Chen Guanghui Li Mingjun Rao 《International Journal of Minerals,Metallurgy and Materials》 2025年第10期2418-2428,共11页
The growing demand for Ni and Co in the new energy sector necessitates efficient extraction methods for limonitic laterite ores.This study demonstrated the effectiveness of sodium sulfate(Na_(2)SO_(4))as an additive f... The growing demand for Ni and Co in the new energy sector necessitates efficient extraction methods for limonitic laterite ores.This study demonstrated the effectiveness of sodium sulfate(Na_(2)SO_(4))as an additive for enhancing the co-enrichment of Ni and Co during solid-state reduction.Na_(2)SO_(4)promoted the formation of two distinct liquid phases,low-melting-point FeS-FeO-Fe and NaAlSiO_(4)-NaFeSiO_(4),facilitating the migration and aggregation of Ni-Co-Fe alloy particles,leading to a high-grade alloy powder with 11.98wt%Ni and 0.88wt%Co and recoveries of 94.03%and 80.16%,respectively.Ni-Co-Fe particle growth was mainly driven by the FeS-FeO-Fe eutectic melt,aligned with a liquid-phase sintering mechanism.Pilot-scale rotary kiln experiments validated the industrial feasibility of this approach,which offers a promising solution for the sustainable extraction of these critical metals. 展开更多
关键词 limonite laterite ore reductive roasting sodium sulfate Ni-Co-Fe alloy particle aggregation rotary kiln
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The Reductive Amination of Biomass-Based Aldehydes and Alcohols towards 2,5-bis(aminomethyl)furan:Progress,Challenges and Prospects
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作者 Li Ji Jiawei Mao +1 位作者 Ruixiang Li Jiaqi Xu 《Journal of Renewable Materials》 2025年第9期1683-1706,共24页
Primary diamines play an important role in the chemical industry,where they are widely used as raw materials for the manufacture of pharmaceuticals and polymers.Currently,primary diamines are mainly derived from petro... Primary diamines play an important role in the chemical industry,where they are widely used as raw materials for the manufacture of pharmaceuticals and polymers.Currently,primary diamines are mainly derived from petroleum,while harsh or toxic conditions are often needed.Biomass is abundant and renewable,which serves as a promising alternative raw material to produce primary diamines.This review primarily focuses on the synthesis of 2,5-bis(aminomethyl)furan(BAMF),a bio-based diamine with potential as a biomonomer for polyamides and polyureas.Specifically,this review emphasizes the synthesis of BAMF fromthree biomass-derived alcohols and aldehydes,namely 5-hydroxymethylfurfural(HMF),2,5-bis(hydroxymethyl)furan(BHMF),and 2,5-diformylfuran(DFF).These are the key substrates to get BAMF and could be readily obtained from carbohydrates.Even though great effort has been put into the synthesis of BAMF,it remains a tough problem to obtain BAMF with a high yield at a low cost due to the inevitable side reactions,such as unwanted hydrogenation reactions and condensation reactions.Many strategies have been proposed to solve this problem,such as the hydrogen-borrowing strategy and stepwise reductive amination strategy.Herein,we will summarize the key advancements in this area,and discuss the challenges that need to be responded in the future,hoping to provide an insight into the design and development of a more efficient system for the production of biomass-derived diamines. 展开更多
关键词 Primary diamine biomass upgrading reductive amination 2 5-bis(aminomethyl)furan
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Smart Global Poverty Reduction Cooperation
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作者 LU JIAJUN 《China Today》 2026年第1期39-41,共3页
Experts and officials shared their insights on poverty reduction cooperation and sustainable development during the 2025 International Seminar on Global Poverty Reduction Partnerships.
关键词 sustainable development international seminar OFFICIALS global poverty reduction cooperation experts poverty reduction
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Fe-loaded S,N co-doped carbon catalyst for oxygen reduction reaction with enhanced electrocatalytic activity and durability
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作者 Shengzhi He Chunwen Sun 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期315-321,共7页
Heteroatom-doped carbon is considered a promising alternative to commercial Pt/C as an efficient catalyst for the oxygen reduction reaction(ORR).This study presents the synthesis of iron-loaded,sulfur and nitrogen co-... Heteroatom-doped carbon is considered a promising alternative to commercial Pt/C as an efficient catalyst for the oxygen reduction reaction(ORR).This study presents the synthesis of iron-loaded,sulfur and nitrogen co-doped carbon(Fe/SNC)via in situ incorporation of 2-aminothiazole molecules into zeolitic imidazolate framework-8(ZIF-8)through coordination between metal ions and organic ligands.Sulfur and nitrogen doping in carbon supports effectively modulates the electronic structure of the catalyst,increases the Brunauer-Emmett-Teller surface area,and exposes more Fe-N_(x)active centers.Fe-loaded,S and N co-doped carbon with Fe/S molar ratio of 1:10(Fe/SNC-10)exhibits a half-wave potential of 0.902 V vs.RHE.After 5000 cycles of cyclic voltammetry,its half-wave potential decreases by only 20 mV vs.RHE,indicating excellent stability.Due to sulfur s lower electronegativity,the electronic structure of the Fe-N_(x)active center is modulated.Additionally,the larger atomic radius of sulfur introduces defects into the carbon support.As a result,Fe/SNC-10 demonstrates superior ORR activity and stability in alkaline solution compared with Fe-loaded N-doped carbon(Fe/NC).Furthermore,the zinc-air battery assembled with the Fe/SNC-10 catalyst shows enhanced performance relative to those assembled with Fe/NC and Pt/C catalysts.This work offers a novel design strategy for advanced energy storage and conversion applications. 展开更多
关键词 zinc-air batteries oxygen reduction reaction iron-loaded nitrogen-doped carbon sulfur-doping
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Optimizing the RuCo Ratio for More Efficient and Durable Oxygen Reduction in Acidic Media
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作者 WEI Mingrui ZHANG Shuai +1 位作者 HUANG Shuo WANG Chao 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期25-32,共8页
The development of Pt-free catalysts for the oxygen reduction reaction(ORR)is a great issue for meeting the cost challenges of proton exchange membrane fuel cells(PEMFCs)in commercial applications.In this work,a serie... The development of Pt-free catalysts for the oxygen reduction reaction(ORR)is a great issue for meeting the cost challenges of proton exchange membrane fuel cells(PEMFCs)in commercial applications.In this work,a series of RuCo/C catalysts were synthesized by NaBH4 reduction method under the premise that the total metal mass percentage was 20%.X-ray diffraction(XRD)patterns and scanning electron microscopy(SEM)confirmed the formation of single-phase nanoparticles with an average size of 33 nm.Cyclic voltammograms(CV)and linear sweep voltammograms(LSV)tests indicated that RuCo(2:1)/C catalyst had the optimal ORR properties.Additionally,the RuCo(2:1)/C catalyst remarkably sustained 98.1% of its activity even after 3000 cycles,surpassing the performance of Pt/C(84.8%).Analysis of the elemental state of the catalyst surface after cycling using X-ray photoelectron spectroscopy(XPS)revealed that the Ru^(0) percentage of RuCo(2:1)/C decreased by 2.2%(from 66.3% to 64.1%),while the Pt^(0) percentage of Pt/C decreased by 7.1%(from 53.3% to 46.2%).It is suggested that the synergy between Ru and Co holds the potential to pave the way for future low-cost and highly stable ORR catalysts,offering significant promise in the context of PEMFCs. 展开更多
关键词 ELECTROCATALYSIS oxygen reduction DURABILITY RuCo/C fuel cell
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Recent Advances in Regulation Strategy and Catalytic Mechanism of Bi-Based Catalysts for CO_(2) Reduction Reaction
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作者 Jianglong Liu Yunpeng Liu +5 位作者 Shunzheng Zhao Baotong Chen Guang Mo Zhongjun Chen Yuechang Wei Zhonghua Wu 《Nano-Micro Letters》 2026年第1期647-697,共51页
Using photoelectrocatalytic CO_(2) reduction reaction(CO_(2)RR)to produce valuable fuels is a fascinating way to alleviate environmental issues and energy crises.Bismuth-based(Bi-based)catalysts have attracted widespr... Using photoelectrocatalytic CO_(2) reduction reaction(CO_(2)RR)to produce valuable fuels is a fascinating way to alleviate environmental issues and energy crises.Bismuth-based(Bi-based)catalysts have attracted widespread attention for CO_(2)RR due to their high catalytic activity,selectivity,excellent stability,and low cost.However,they still need to be further improved to meet the needs of industrial applications.This review article comprehensively summarizes the recent advances in regulation strategies of Bi-based catalysts and can be divided into six categories:(1)defect engineering,(2)atomic doping engineering,(3)organic framework engineering,(4)inorganic heterojunction engineering,(5)crystal face engineering,and(6)alloying and polarization engineering.Meanwhile,the corresponding catalytic mechanisms of each regulation strategy will also be discussed in detail,aiming to enable researchers to understand the structure-property relationship of the improved Bibased catalysts fundamentally.Finally,the challenges and future opportunities of the Bi-based catalysts in the photoelectrocatalytic CO_(2)RR application field will also be featured from the perspectives of the(1)combination or synergy of multiple regulatory strategies,(2)revealing formation mechanism and realizing controllable synthesis,and(3)in situ multiscale investigation of activation pathways and uncovering the catalytic mechanisms.On the one hand,through the comparative analysis and mechanism explanation of the six major regulatory strategies,a multidimensional knowledge framework of the structure-activity relationship of Bi-based catalysts can be constructed for researchers,which not only deepens the atomic-level understanding of catalytic active sites,charge transport paths,and the adsorption behavior of intermediate products,but also provides theoretical guiding principles for the controllable design of new catalysts;on the other hand,the promising collaborative regulation strategies,controllable synthetic paths,and the in situ multiscale characterization techniques presented in this work provides a paradigm reference for shortening the research and development cycle of high-performance catalysts,conducive to facilitating the transition of photoelectrocatalytic CO_(2)RR technology from the laboratory routes to industrial application. 展开更多
关键词 Bismuth-based catalysts CO_(2)reduction reaction Regulation strategy Catalytic mechanism REVIEW
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Reductive leaching of manganese oxide ores using waste tea as reductant in sulfuric acid solution 被引量:18
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作者 唐清 钟宏 +2 位作者 王帅 李进中 刘广义 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期861-867,共7页
Manganese oxide ores from Gabon and Xiangxi were leached with waste tea as reductant in dilute sulfuric acid solution. The effects of waste tea dosage, concentration of sulfuric acid, liquid-to-solid ratio, leaching t... Manganese oxide ores from Gabon and Xiangxi were leached with waste tea as reductant in dilute sulfuric acid solution. The effects of waste tea dosage, concentration of sulfuric acid, liquid-to-solid ratio, leaching temperature and reaction time on leaching process were explored. The leaching efficiency of Gabonese manganese oxide ore reached almost 100% under the optimal condition which was determined as follows: manganese oxide ore to waste tea mass ratio of 10:1, sulfuric acid concentration of 2.5 molFL, liquid-to-solid ratio of 7.5:1, leaching temperature of 368 K, time of 8 h. The leaching efficiency of Xiangxi manganese oxide ore reached 99.8% under the optimal condition which was determined as follows: manganese oxide ore to waste tea mass ratio of 10:1, sulfuric acid concentration of 1.7 mol/L, liquid-to-solid ratio of 7.5:1, leaching temperature of 368 K, time of 8 h. The leaching process followed the internal diffusion controlled kinetic model, and the apparent activation energies of Gabonese manganese oxide ore and Xiangxi manganese oxide ore were calculated to be 38.2 kJ/mol and 20.4 kJ/mol, respectively. The morphological changes and mineralogical forms of the ore before and after the chemical treatment were discussed with the support of XRD analysis and SEM analysis. 展开更多
关键词 manganese oxide ore waste tea reductant LEACHING
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Reductive leaching of zinc and indium from industrial zinc ferrite particulates in sulphuric acid media 被引量:9
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作者 张帆 魏昶 +3 位作者 邓志敢 李存兄 李兴彬 李旻廷 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第9期2495-2501,共7页
Zinc ferrite is the principal constituent in zinc neutral-leach residue(NLR) which is commonly treated by hot-acid leaching in electrolytic zinc plants. Reductive leaching of zinc ferrite with sphalerite concentrate... Zinc ferrite is the principal constituent in zinc neutral-leach residue(NLR) which is commonly treated by hot-acid leaching in electrolytic zinc plants. Reductive leaching of zinc ferrite with sphalerite concentrate as a reducing agent was performed. It was found that leaching of zinc ferrite in the presence of sphalerit concentrate was a viable process that effectively extracted zinc and indium and converted Fe^3+ into Fe^2+ at the same time. Reflux leaching tests by two stages were performed to achieve extractions of 98.1% for zinc and 97.5% for indium, and a Fe^2+/Fe^3+ molar ratio of 9.6 in leach solution was also obtained. The leaching behaviors of other elements, such as iron, copper and tin were also studied. The results showed that iron and copper were completely leached, whereas tin presented lower extraction values. 展开更多
关键词 reductive leaching zinc ferrite ZINC INDIUM sphalerite concentrate
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Mechano-chemical sulfidization of zinc oxide by grinding with sulfur and reductive additives 被引量:8
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作者 柴立元 梁彦杰 +5 位作者 柯勇 闵小波 唐崇俭 张海静 谢先德 袁翠玉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第4期1129-1138,共10页
A novel process for sulfidation of ZnO by co-grinding with sulfur and reductive additives (P, Fe, A1, and Mg) was developed. The sulfidation extent of ZnO with the addition of P, Fe, A1 or Mg can reach 85.2%, 81.6%,... A novel process for sulfidation of ZnO by co-grinding with sulfur and reductive additives (P, Fe, A1, and Mg) was developed. The sulfidation extent of ZnO with the addition of P, Fe, A1 or Mg can reach 85.2%, 81.6%, 96.7% and 92.6% after grinding for 4, 6, 1 and 1 h, respectively. Based on the chemical phase composition analysis and morphological characteristics of sulfidized products by XRD, SEM and TEM, a possible reaction mechanism, mechanically induced self-propagating reaction (MSR), was proposed to explain the sulfidization reaction. In addition, the floatability of sulfidized products was investigated for the recovery of metal sulfide and ZnS can be concentrated with a high concentration ratio and concentrate grade. By using the sulfidizing process, it is expected that the recovery of zinc from the wastes or purification of heavy-metal-containing hazardous residues is technically feasible. 展开更多
关键词 mechano-chemical sulfidization zinc oxide reductive additives self-propagating reaction FLOTATION
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Reaction behavior of ferric oxide in system Fe_2O_3-SiO_2-Al_2O_3 during reductive sintering process 被引量:7
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作者 周秋生 李闯 +3 位作者 李小斌 彭志宏 刘桂华 齐天贵 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第3期842-848,共7页
Pure compounds and kaolin were employed to investigate the reaction behavior of ferric oxide in thetrinarysystem Fe2O3?SiO2?Al2O3 during reductive sintering process. The thermodynamic analyses and reductive sintering ... Pure compounds and kaolin were employed to investigate the reaction behavior of ferric oxide in thetrinarysystem Fe2O3?SiO2?Al2O3 during reductive sintering process. The thermodynamic analyses and reductive sintering experimental results show that ferrous oxide generated from the reduction of ferric oxide by carbon can react with silicon dioxide and aluminum oxide to form ferrous silicate and hercynite at 1173 K, respectively. In the trinary system Fe2O3?SiO2?Al2O3, ferrous oxide obtained from ferric oxide reduction preferentially reacts with aluminum oxide to form hercynite, and the reaction of ferrous oxide with silicon dioxide occurs only when there is surplus ferrous oxide after the exhaustion of aluminum oxide. When sintering temperature rises to 1473 K, hercynite further reacts with silicon dioxide to form mullite and ferrous oxide. Results presented in this work may throw a new light upon the separation of alumina and silica present in Al/Fe-bearing materials with low mass ratio of alumina to silica in alumina production. 展开更多
关键词 reductive sintering ferric oxide ferrous silicate HERCYNITE MULLITE KAOLIN
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Reductive acid leaching of cadmium from zinc neutral leaching residue using hydrazine sulfate 被引量:5
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作者 张纯 闵小波 +3 位作者 张建强 王密 周波生 沈忱 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第12期4175-4182,共8页
Zinc neutral leaching residue(ZNLR) from hydrometallurgical zinc smelting processing can be determined as hazardous intermediate containing considerable amounts of Cd and Zn which have great threats to the environme... Zinc neutral leaching residue(ZNLR) from hydrometallurgical zinc smelting processing can be determined as hazardous intermediate containing considerable amounts of Cd and Zn which have great threats to the environment. The ZNLR contained approximately 35.99% Zn, 15.93% Fe and 0.26% Cd, and Cd mainly existed as ferrites in the ZNLR in this research. Reductive acid leaching of ZNLR was investigated. The effects of hydrazine sulfate concentration, initial sulfuric acid concentration, temperature, duration and liquid-to-solid ratio on the extraction of Cd, Zn and Fe were examined. The extraction efficiencies of Cd, Zn and Fe reached 90.81%, 95.83% and 94.19%, respectively when the leaching parameters were fixed as follows: hydrazine sulfate concentration, 33.3 g/L; sulfuric acid concentration, 80 g/L; temperature, 95 °C; duration of leaching, 120 min; liquid-to-solid ratio, 10 m L/g and agitation, 400 r/min. XRD and SEM-EDS analyses of the leaching residue confirmed that lead sulfate(Pb SO4) and hydrazinium zinc sulfate((N2H5)2Zn(SO4)2) were the main phases remaining in the reductive leaching residue. 展开更多
关键词 reductive acid leaching zinc neutral leaching residue hydrazine sulfate CADMIUM
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Catalytic reductive dechlorination of p-chlorophenol in water using Ni/Fe nanoscale particles 被引量:18
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作者 ZHANG Wei-hua QUAN Xie ZHANG Zhuo-yong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第3期362-366,共5页
Nanoscale bimetallic Ni/Fe particles were synthesized from the reaction of sodium borohydride (NaBH4) with reduction of Ni^2+ and Fe^2+ in aqueous solution. The obtained Ni/Fe particles were characterized by TEM ... Nanoscale bimetallic Ni/Fe particles were synthesized from the reaction of sodium borohydride (NaBH4) with reduction of Ni^2+ and Fe^2+ in aqueous solution. The obtained Ni/Fe particles were characterized by TEM (transmission electron microscope), XRD (X-ray diffractometer), and N2-BET. The dechlorination activity of the Ni/Fe was investigated using p-chlorophenol (p-CP) as a probe agent. Results demonstrated that the nanoscale Ni/Fe could effectively dechlorinate p-CP at relatively low metal to solution ratio of 0.4 g/L (Ni 5 wt%). The target with initial concentration ofp-CP 0.625 mmol/L was dechlorinted completely in 60 rain under ambient temperature and pressure. Factors affecting dechlorination efficiency, including reaction temperature, pH, Ni loading percentage over Fe, and metal to solution ratio, were investigated. The possible mechanism of dechlorination ofp-CP was proposed and discussed. The pseudo-first- order reaction took place on the surface of the Ni/Fe bimetallic particles, and the activation energy of the dechlorination reaction was determined to be 21.2 kJ/mol at the temperature rang of 287-313 K. 展开更多
关键词 Ni/Fe bimetal nanoscale particles catalytic reduction p-CP DECHLORINATION
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Preparation,structural characterization of a novel egg-shell palladium sulfide catalyst and its application in selective reductive alkylation reaction 被引量:5
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作者 Qun Feng Zhang Jia Chun Wu +7 位作者 Chang Su Feng Feng Qiao Ling Ding Zhao Lian Yuan Hong Wang Lei Ma Chun Shan Lu Xiao Nian Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第10期1111-1114,共4页
A novel egg-shell Pd-S catalyst with palladium metal as the core and a membrane of palladium sulfide as the surface has been prepared by sulphidizing Pd/C with H2S. This catalyst is effective for the reductive alkylat... A novel egg-shell Pd-S catalyst with palladium metal as the core and a membrane of palladium sulfide as the surface has been prepared by sulphidizing Pd/C with H2S. This catalyst is effective for the reductive alkylation of p-amino diphenylamine (PADPA) and methylisobutyl ketone (MIBK) to afford N-(1,3-dimethylbutyl)-N^-phenyl-p-phenylenedianine (DBPPD) with conversion up to 99.42% and selectivity to 97.46%. Comparing with the other common palladium sulfide catalysts, the membrane of palladium sulfide on the surface and the core of palladium metal cause the Pd on the surface of the new catalyst in a lower sulfur coordination, which improves its activity. Our result indicates that this new egg-shell Pd-S/C is an efficient hydrogenation catalyst. 展开更多
关键词 HaS Palladium sulfide Egg-shell reductive alkylation
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