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Electrochemical Activation of CO_2 for the Synthesis of Ethyl Carbanilate under Mild Conditions

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Chemical Research in Chinese Universities 2007年第6期23卷 708-711页

作者： NIU Dong-fang XU Cheng-tian LUO Yi-wen ZHANG Li LU Jia-xing Shanghai Key laboratory of Green Chemistry and Chemical processes Department of Chemistry East China Normal University Shanghai 200062 P. R. China

A novel electrochemical procedure for the synthesis of ethyl carbanilate from aniline and carbon dioxide was developed via the selective cathodic reduction of carbon dioxide in CO2-saturated DMF solution containing 0. 1 mol/L TEABr at room temperature, followed by the addition of Eft as an alkylating agent. The synthesis was carried outun der mild[p（CO2） = 1.0×10^5 Pa, t =20 ℃ ] and safe conditions. Influences of the nature of the electrodes, the current densities, the passed charges during electrolysis, temperatures, and supporting electrolytes on the yield of ethyl carbanilate were studied to optimize the electrolytic conditions. The selectivity of ethyl carbanilate is 100%.

关键词： Carbon dioxide Electrochemistry Aniline Synthesis Ethyl carbanilate Mild condition

Co-electrolysis toward value-added chemicals

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Science China Materials 2022年第1期65卷 1-9页

作者： Lisong Chen Jianlin Shi Shanghai Key laboratory of Green Chemistry and Chemical processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China State Key laboratory of High Performance Ceramics and Superfine Microstructures Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China

Current major electrocatalytic reactions,such as hydrogen evolution reaction,carbon dioxide reduction reaction,and nitrogen reduction reaction,focus on single-target chemical production,which suffers from strong competitive reactions at the same electrodes and/or high energy barrier reactions at the counterpart *** co-electrolysis of more than one kind,typically two kinds,of chemical precursors in one electrolytic system is therefore a highly attractive strategy for both energy input reduction and concurrent production of double value-added *** progress has been achieved in this area recently,and a timely review on this specific topic will be highly *** this review,the reported co-electrolysis systems are classified into four categories:(1)agent sacrificing at one electrode promoting electrochemical precursor conversion at the other;(2)parallel electrochemical precursor conversions,i.e.,electrosyntheses,simultaneously at both sides;(3)electrochemical conversions of two precursors at both sides into one/the same product;(4)double/multiple electrochemical conversions at one *** current challenges and future opportunities of co-electrolysis toward high value-added products are discussed at the end.

关键词： co-electrolysis value-added chemicals electrocatalysts

Effect of hafnium and molybdenum addition on inclusion characteristics in Co-based dual-phase high-entropy alloys

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1639-1650页

作者： Yong Wang Wei Wang Joo Hyun Park Wangzhong Mu Key laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education&Hubei Provincial Key laboratory for New processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan 430081China Department of Materials Science and Engineering KTH Royal Institute of TechnologySE-10044StockholmSweden Department of Chemical Engineering Northeast Electric Power UniversityJilin 132012China Department of Materials Science and Chemical Engineering Hanyang UniversityAnsan 15588Korea Engineering Materials Division of Materials ScienceDepartment of Engineering Science and MathematicsLuleå University of Technology97187 LuleåSweden

Specific grades of high-entropy alloys(HEAs)can provide opportunities for optimizing properties toward high-temperature *** this work,the Co-based HEA with a chemical composition of Co_(47.5)Cr_(30)Fe_(7.5)Mn_(7.5)Ni_(7.5)(at%)was *** refractory metallic elements hafnium(Hf)and molybdenum(Mo)were added in small amounts(1.5at%)because of their well-known positive effects on high-temperature *** characteristics were comprehensively explored by using a two-dimensional cross-sectional method and extracted by using a three-dimensional electrolytic extraction *** results revealed that the addition of Hf can reduce Al_(2)O_(3)inclusions and lead to the formation of more stable Hf-rich inclusions as the main *** addition cannot influence the inclusion type but could influence the inclusion characteristics by affecting the physical parameters of the HEA *** calculated coagulation coefficient and collision rate of Al_(2)O_(3)inclusions were higher than those of HfO_(2)inclusions,but the inclusion amount played a larger role in the agglomeration behavior of HfO_(2)and Al_(2)O_(3)*** impurity level and active elements in HEAs were the crucial factors affecting inclusion formation.

关键词： high-entropy alloy non-metallic inclusion agglomeration thermodynamics alloying

Microwave diagnostics of pulsed atmospheric discharge with electrolytic electrode and long-lived luminous formation in its afterglow

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High Voltage 2024年第1期9卷 127-136页

作者： Shixin Zhao Xingbao Lyu Aleksandr Astafiev Chengxun Yuan Lin Miao Jingfeng Yao Ying Wang Anatoly Kudryavtsev Aleksandr Chirtsov Gennadii Shabanov Zhongxiang Zhou School of Physics Harbin Institute of TechnologyHarbinChina Physics Department Saint Petersburg Electrotechnical University“LETI”St.PetersburgRussia Heilongjiang Provincial Key laboratory of plasma Physics and Application Technology HarbinChina Physics Department St.Petersburg State UniversitySt.PetersburgRussia Konstantinov Petersburg Nuclear Physics Institute National Research Centre“Kurchatov Institute”GatchinaRussia

The Gatchina discharge phenomenon holds significant promise as a laboratory model for simulating ball ***,crucial aspects concerning the plasma components of the resulting afterglow remain ***,the measurement of the electron density,a critical parameter,has not been fully achieved thus *** this study,microwave diagnostics and video recording were employed during a pulsed Gatchina discharge,along with synchronous measurement of discharge current and *** antennas were positioned at different heights to enable separate diagnosis of the discharge and the ensuing long-lived *** findings revealed that during the active phase of the Gatchina discharge,the plasma density was substantial enough to cause reflection of an electromagnetic wave with a frequency of 20 GHz from this highly conductive *** the afterglow,the signal experienced only a moderate weakening of 10–20 percent,facilitating the determination of the time dependence of average electron density during the afterglow's passage between the two *** measurements verified the unusually slow plasma decay in the afterglow of the Gatchina discharge,suggesting the potential significance of chemi-ionisation processes involving long-lived(metastable)particles.

关键词： holds luminous electrolytic

面向高附加值化学品制备的共电解催化（英文）

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Science China Materials 2021年

作者：陈立松施剑林 Shanghai Key laboratory of Green Chemistry and Chemical processes School of Chemistry and Molecular Engineering East China Normal University State Key laboratory of High Performance Ceramics and Superfine Microstructures Shanghai Institute of Ceramics Chinese Academy of Sciences

当前常见的电催化反应大多以制备某一种化学品为目标,如水分解析氢、二氧化碳还原制备碳基化学品、氮气还原制氨等,然而这些电催化反应均面临着严重的竞争反应且需要克服对电极反应较大的能垒.在同一电解池中共电解两种或多种化学原料...

当前常见的电催化反应大多以制备某一种化学品为目标,如水分解析氢、二氧化碳还原制备碳基化学品、氮气还原制氨等,然而这些电催化反应均面临着严重的竞争反应且需要克服对电极反应较大的能垒.在同一电解池中共电解两种或多种化学原料有望减弱竞争反应并降低对电极反应能垒,从而达到在较低能耗下制备高附加值化学品的目的.虽然共电解催化体系已经有了一定的发展,但目前尚未见到该主题相关的综述.本综述将共电解催化体系分为:(1)牺牲剂促进的电化学转化;(2)两电极上同时分别进行的电化学转化;(3)两电极共同作用将两种原料转化为一种/类产物;(4)在一个电极上将多种原料转化为一种产物.最后提出共电解催化体系未来发展面临的诸多机遇和挑战.

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Thermodynamic properties of bioleaching liquid mixtures with and without mesophilic bacteria at different temperatures

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Rare Metals 2007年第6期26卷 528-535页

作者： LIU Meilin RUAN Renman WEN Jiankang WANG Dianzuo National Engineering laboratory of Biohydrometallurgy General Research Institute for Non-Ferrous Metals Beijing 100088 China

In this work, low-grade copper sulfide mine has been treated by the bioleaching process using native cultures of Acidithiobacillus ferrooxidans. The bioleaching experiments were carded out in shake flasks at pH 2.0, 180 ***^-1 and 30℃ for mesophilic bacteria The conductivity of copper bioleaching liquid was determined by the electric conductivity method at temperatures ranging from 298 K to 313 K. The ionic activity coefficients were estimated using Debye-Hucker and Osager-Falkenlagen equations. Meanwhile, the effects of temperature and concentrtion on the mean ionic activity coefficients were discussed. The relative partial molar free energies, enthalpies and entropies of copper teaching solution at above experimental temperatures were calculated. The behaviors of change of relative partial molar quantities were discussed on the basis of electrolytic solution theory. Simultaneously, the thermodynamic characters of bioleaching solution with and without mesophilic bacteria were compared. The existence of mesophilic bacteria changed the Fe^3＋/Fe^2＋ ratio, which resulted in the difference of ionic interaction. The experimental data show that the determination of the thermodynamic properties during the bioleaching processes should be important.

关键词： activity coefficient thermodynamic properties bioleaching solution mesophilic bacteria

Ultra-stable metal nano-catalyst synthesis strategy:a perspective

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Rare Metals 2020年第2期39卷 113-130页

作者： Xiao-Qing Cao Jun Zhou Song Li Gao-Wu Qin Key laboratory for Anisotropy and Texture of Materials School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China

Supported metal nanoparticles(NPs)as an important heterogeneous catalyst have been widely applied in various industrial *** the catalytic reaction,size of the particles plays an important role in determining their catalytic ***,the small particles exhibit superior catalytic activity in comparison with the larger particles because of an increase in lowcoordinated metal atoms on the particle surface that work as active sites,such as edges and corner ***,these small NPs are typically unstable and tend to migrate and coalescence to reduce their surface free energy during the real catalytic processes,particularly in high-temperature ***,a means to fabricate stable small metal NP catalysts with excellent sinter-resistant performance is necessary for maintaining their high catalytic *** this study,we have summarized recent advances in stabilizing metal NPs from two aspects including thermodynamic and kinetic *** former mainly involve preparing uniform NPs(with an identical size and homogeneous distribution)in order to restrain Ostwald ripening to achieve stability,while the latter primarily involves fixing metal NPs in some special confinement materials(e.g.,zeolites,mesoporous silica and mesoporous carbons),encapsulating NPs using an oxide-coating film(e.g.,forming core-shell structures),or constructing strong metal-support interactions to improve *** the end of this review,we highlight our recent work on the preparation of high-stability metal catalysts via a unique interfacial plasma electrolytic oxidation technology,that is,metal NPs are well embedded in a porous MgO layer that has both high thermal stability and excellent catalytic activity.

关键词： Nano-catalysts Thermal stability Sinterresistant Synthesis strategy

100 W-class green hydrogen production from ammonia at a dual-layer electrode containing a Pt-Ir catalyst for an alkaline electrolytic process

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Journal of Energy Chemistry 2024年第6期93卷 352-360,I0009页

作者： Donghyun Yoon Sunki Chung Minjun Choi Eunhyeok Yang Jaeyoung Lee School of Earth Sciences and Environmental Engineering Gwangju Institute of Science and Technology(GIST)Gwangju 61005Republic of Korea International Future Research Center of Chemical Energy Storage and Conversion processes GISTGwangju 61005Republic of Korea Ertl Center for Electrochemistry and Catalysis GISTGwangju 61005Republic of Korea TKG Huchems Co.Ltd 963Sangam-roYeosu-siJeollanam-do 59614Republic of Korea

Ammonia allows storage and transport of hydrogen over long distances and is an attractive potential hydrogen *** decomposition has recently been used for the conversion of ammonia to hydrogen and is regarded as a future technology for production of CO_(2)-free pure ***,a heterostructural Pt-Ir dual-layer electrode is developed and shown to achieve successful long-term operation in an ammonia electrolyzer with an anion exchange membrane(AEM).This electrolyzer consisted of eight membra ne electrode assemblies(MEAs)with a total geometric area of 200 cm~2 on the anode side,which resulted in a hydrogen production rate of 25 L h~(-1).We observed the degradation in MEA performance attributed to changes in the anode catalyst layer during hydrogen production via ammonia ***,we demonstrated the relationship between the ammonia oxidation reaction(AOR)and the oxygen evolution reaction(OER).

关键词： Ammonia oxidation Dual-layer catalyst Green hydrogen electrolytic process Oxygen evolution reaction

Recovery of rare earth elements from rare earth molten salt electrolytic slag via fluorine fixation by MgCl_(2)roasting

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Journal of Rare Earths 2024年第10期42卷 1979-1987页

作者： Minghui Zhang Bingxuan He Yinliang Liu Luewei Xu Yong Liang Faculty of Metallurgical Engineering Jiangxi University of Science and TechnologyGanzhou341000China Key laboratory of Ionic Rare Earth Resources and Environment Ministry of Natural ResourcesGanzhou3410ooChina Jiangxi Provincial Key laboratory of Green and Low Carbon Metallurgy for Strategic Nonferrous Metals Ganzhou3410ooChina

Rare earth fluoride molten-salt electrolytic slag(REFES)is a precious rare earth element(REE)secondary resource,and conside rable amounts of REEs exist in REFES as REF_(3);they are difficult to dissolve in acid or water and impede efficient REE *** REFES recovery,the REF_(3)species in REFES are usually transformed into acid-soluble rare earth compounds by NaOH roasting or sulfating roasting and then extracted by acid leaching,Moreover,the fluorides in REFES are released as HF gas in the roasting process or enter the liquid phase during the water washing process;both of these processes cause fluorine *** the fluorine into the solid slag provides a way to avoid fluorine *** this study,a novel method was proposed to extract REEs from REFES via MgCl_(2)roasting followed by HCl *** calculations and the rmogravimetry-differential thermal analyses(TG-DTA)were conducted to investigate the reactions occurring in the roasting process,First,MgCl_(2)reacts with the REF_3and RE_(2)O_(3)to form RECl_(3)and REOCl,***,the RECI_(3)absorbs water and forms RE(OH)_(3).Third,MgCl_(2)·6H_(2)O is gradually dehydrated to MgCl_(2)·2H_(2)O and reacts with REF_(3)and RE(OH)_(3),and REOCl,MgF_(2)and MgO are *** HCl leaching,the REOCl in the roasting products is leached by HCl acid,while fluoride re mains in the solid slag as MgF_*** optimum experimental conditions are as follows:mass ratio of MgCl_(2)to REFES of 30%,roasting temperature of 700℃,roasting time of 2 h,hydrochloride acid concentration of 4 mol/L,leaching time of 2 h,leaching temperature of 90℃and leaching L/S ratio of 20:*** efficiencies for total leaching of the REEs,La,Ce,Pr,and Nd are 99.13%,99.20%,98.42%,99.38%,and 99.08%,***,the concentration of fluoride in the leaching solution is 2.191×10^(-6)mol/*** method has a short process flow with low reagent costs,and the problem of fluoride pollution from REFES recovery is solved;

关键词： Rare earths Molten-salt electrolytic slag Fluorine Recovery Leaching