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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

Electrochemical degradation of p-nitrophenol with different processes

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Journal of Environmental Sciences 2010年第4期22卷 500-506页

作者： Ping Jiang,Jiti Zhou,Aili Zhang,Yijiang Zhong Key laboratory of Industrial Ecology Environmental Engineering(MOE),School of Environmental & Biological Science & Technology,Dalian University of Technology,Dalian116024,China. Key laboratory of Industrial Ecology Environmental Engineering (MOE) School of Environmental & Biological Science & Technology Dalian University of Technology Dalian116024 China

The electrochemical degradation ofp-nitrophenol （PNP） under different conditions was investigated. The electrochemical behavior of PNP and its reduction product p-aminophenol （PAP） on stainless steel cathode and Ti/Pt anode through cyclic voltammetry were observed. Electrochemical degradation process was performed in an undivided cell and 92% PNP was removed corresponding to a 22% total organic carbon removal. A divided cell was also used and it was found that PNP degradation was mainly attributed to cathodic reduction, while anodic oxidation was responsible for PNP removal due to the reaction with hydroxyl radicals and surface oxide generated on the anode. The sequential electrolytic processes, reduction-oxidation and oxidation-reduction, were compared in the divided cell. In the case of reduction-oxidation process, the total organic carbon removal reached 40%, but PNP removal was the same with the undivided cell. A black deposit was found in the effluent and identified by Fourier transform infrared spectroscopy as a polymer of PAP produced by the 1,4-addition reaction of quinoneimine. Intermediates left in the solution such as hydroquinone, p-benzoquinone and PAP were determined by high performance liquid chromatography. Whereas, the oxidation-reduction process proved unsatisfying.

关键词： degradation cathodic reduction anodic oxidation sequential electrolysis

pH-distribution of cerium species in aqueous systems

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Journal of Rare Earths 2012年第6期30卷 559-562页

作者： B.Bouchaud J.Balmain *** F.Pedraza University of La Rochelle Laboratory of Engineering Science for the Environment LaSIE FRE-CNRS3474Avenue Michel Crépeau 17042 La Rochelle cedex 01FRANCE

Cerium-based oxide coatings can be obtained through either chemical or electrochemical processes on various conductor and semiconductor substrates. In both cases the films develop through a precipitation mechanism, which strongly depends on the solution chemistry. In the particular case of the electrolytic approach, the elaboration parameters play a key role on the interfacial pH modification thereby leading to an indirect precipitation mechanism. Indeed, the nucleation and growth mechanisms of crystallites and the composition of the resulting layers have been shown to be also strongly affected by the deposition conditions as well as by the substrate composition, which could in turn modify the protectiveness provided by such coatings. Therefore a better fundamental understanding of the system is required, in particular of the distribution of cerium-containing species in aqueous solution. To this end, the present work intended to develop a diagram showing the distribution as well as the relative amount of Ce（Ⅲ）/Ce（Ⅳ） species in aqueous media as a fimction of the pH range. The resulting pH-distribution diagram turned out to be a useful tool to predict the relevant precipitation mechanisms and species involved during the growth of ceriuna-containing films and to draw correlations with the characteristics of the as-deposited films.

关键词： pH-distribution diagram electrodeposition cerium-based oxide films precipitation mechanisms rare earths

Electrochemical Study and Electrodeposition of Copper（I） in Ionic Liquid-reline

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Chemical Research in Chinese Universities 2013年第5期29卷 991-997页

作者： POPESCU Ana-Maria COJOCARU Anca DONATH Cristina CONSTANTIN Virgil laboratory of Molten Salts "Hie Murgulescu" Institute of Physical Chemistry of Romanian Academy Bucharest 060021 Romania Department of Applied Physical Chemistry and Electrochemistry University Politehnica of Bucharest Bucharest 010737 Romania

The authors made the electrochemical studies on the electrode processes during copper electrodeposition with ionic liquids-reline as an electrolytic medium. Reline is a commercial name for a eutectic mixture of choline chloride and urea（1：2, molar ratio）. This new proposed method of copper deposition is an ecological one because the ionic liquids are recyclable, non-volatile and non-toxic. Cyclic voltammetry investigations were conducted at 343 and 353 K in choline chloride-urea（Reline） deep eutectic solvent with single salt CuCl（generally in 0.05--0.38 mol/L concentration range）. Electrochemical impedance spectroscopy investigations were conducted in choline chloride- urea ionic liquid with CuCI（0.05 mol/L）. We investigated both cathodic and anodic processes of Cu＋ ions at different sweep rates in this new electrolytic system based on choline chloride. We have proposed by this an alternative to the classical copper electrodeposition. Coefficient of diffusion, Do, for the system Reline-CuCl is presented and the value of D0 is 1.22× 10^-8 cm2/s.

关键词： Ionic liquid Reline Electrodeposition Cu(I) Coefficient of diffusion

Magnetic field‐enhanced water splitting enabled by bifunctional molybdenum‐doped nickel sulfide on nickel foam

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Carbon Energy 2023年第10期5卷 50-63页

作者： Yuanyuan Zhang Mengxin Chen Ping Guo Yunchen Du Bo Song Xianjie Wang Zaixing Jiang Ping Xu MIIT Key laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbinChina School of Physics Harbin Institute of TechnologyHarbinChina

Herein,we report bifunctional molybdenum-doped nickel sulfide on nickel foam(Mo-NiS_(x)/NF)for magnetic field-enhanced overall water splitting under alkaline *** doping of Mo can lead to optimization of the electronic structure of NiS_(x),which accelerates the dissociation of H2O and the adsorption of OH−in the hydrogen evolution reaction(HER)and the oxygen evolution reaction(OER)processes,*** addition,the magnetically active Mo-NiS_(x)/NF can further enhance the HER and OER activity under an applied magnetic field due to the magnetoresistance effect and the ferromagnetic(FM)exchange-field penetration *** a result,Mo-NiS_(x)/NF requires low overpotentials of 307 mV at 50mA cm^(−2)(for OER)and 136 mV at 10mA cm^(−2)(for HER)under a magnetic field of 10000 ***,the electrolytic cell constructed by the bifunctional Mo-NiS_(x)/NFs as both the cathode and the anode shows a low cell voltage of 1.594 V at 10 mA cm^(−2)with optimal stability over 60 h under the magnetic *** enhancement of the HER and OER processes by an external magnetic field through rational design of electrocatalysts might be promising for overall water splitting applications.

关键词： electron density modulation FM exchange‐field penetration effect magnetic field magnetoresistance effect water splitting

Identification and assessment of environmental burdens of Chinese copper production from a life cycle perspective

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Frontiers of Environmental Science & Engineering 2014年第4期8卷 580-588页

作者： Xiaolong SONG Jianxin YANG Bin LU Bo LI Guangyuan ZENG State Key laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Shanghai Cooperative Centre for WEEE Recycling Shanghai Second Polytechnic University Shanghai 201209 China

The environmental burdens of Chinese copper production have been identified and quantified in the context of typical technologies, materials supplies and environmental emissions by a life cycle approach. Primary and secondary copper production using copper ores and scraps, respectively, were analyzed in detail. The flash and bath smelting approaches and the recycling of copper scraps were selected as representative copper production processes. A quantitative analysis was also conducted to assess the influence of material transport distance in copper production. Life cycle assessment （LCA） results showed that resources depletion and human health contribute significantly to environmental burdens in Chinese copper production. In addition, the secondary copper production has dramatically lower environmental burdens than the primary production. There is no obvious distinction in overall environmental burdens in primary copper production by flash or bath smelting approach. However, resources depletion is lower and the damage to human health is higher for flash smelting approach. Ecosystem quality damage is slight for both approaches. Environ- mental burdens from the mining stage contribute most in all life cycle stages in primary copper production. In secondary copper production, the electrolytic refining stage dominates. Based on the life cycle assessment results, some suggestions for improving environmental performance were proposed to meet the sustainable development of Chinese copper industry.

关键词： copper production environmental burden life cycle assessment refined copper

Electrolysis of Converter Matte in Molten CaCl<sub>2</sub>-NaCl

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Journal of Materials Science and Chemical Engineering 2018年第2期6卷 1-11页

作者： Dan Wang Changyuan Lu Xingli Zou Kai Zheng Zhongfu Zhou Xionggang Lu State Key laboratory of Advanced Special Steel & Shanghai Key laboratory of Advanced Ferrometallurgy School of Materials Science and Engineering Shanghai University Shanghai China Department of Physics Aberystwyth University Aberystwyth UK

The electrolytic production of nickel-copper alloy by electrochemical reduction of converter matte in molten salt has been investigated. The sintered solid porous pellets of Ni3S2, Cu2S and converter matte were electrolyzed at a voltage of 3.0 V in molten CaCl2-NaCl under the protection of argon gas at 700℃, respectively. The electro-reduction processes were investigated and the products were characterized. The results show that the molten salt electro-reduction process can be used to produce nickel, copper and nickel-copper alloy directly from Ni3S2, Cu2S and converter matte precursors in molten CaCl2-NaCl, respectively. CaS would be formed as the intermediate compound during the electro-reduction process, and then the formed CaS can be gradually decomposed and removed with the increase of the electrolysis time. The experimental results show that the molten salt electro-reduction process has the potential to be used for the reduction of sulfide minerals in molten CaCl2-NaCl.

关键词： Converter Matte Electro-Reduction Nickel-Copper Alloy Molten CaCl2-NaCl Solid-State Electrochemistry

Solid-Solid Interface:Construction and Electrochemistry

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Solid-Solid Interface:Construction and Electrochemistry

Preface: Special topic on electrocatalysis & energy science

中国化学会第29届学术年会

作者： Dongping Zhan Yiliang Zhu Dezhi Yang State Key laboratory of Physical Chemistry of Solid Surfaces Department of ChemistryCollege of Chemistry and Chemical Engineering Xiamen University

Electrochemistry explores the charge transfer reaction across the interfaces, such as solid/liquid interface, liquid/liquid interface and solid/solid interface. Most reported charge transfer behaviours across the "solid/solid" interface are involved liquid electrolyte. For example, in the lithium-ion batteries, the redox of cobalt-based active material is coupled by the heterogeneous intercalation/deintercalation of Li+ ions, which is existed in the electrolyte solution. In another words, the electron transfer occurs at the interface between the solid current collector and the solid active material while the ion transfer occurs at the interface between the solid active material and the liquid electrolyte solution. We employ SECM to construct the pure solid-solid interface and to study the electron transfer phenomena therein. That means there is no liquid electrolyte environment. When the electron transfer occurs at the solid/solid interface, the counterion transfer will occur in the crystal due to the crystalline defects. For example, the NaCl microcrystals doped with hybrid iron hydroxide-oxide were cultured between a pair of electrodes on a microchip. The multi-step electron transfer processes of iron from Fe（0） to Fe（VI） through Fe（II） and Fe（III） were observed. In this presentation, we would like show the electrochemistry of solid/solid interface in the absence of liquid electrolytic environment.

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来源： cnki会议评论

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Science China Chemistry 2020年第11期63卷 1515-1516页

作者： Changzheng Wu Gang Wu Guihua Yu Hefei National laboratory for Physical Science at the Microscale CAS Center for Excellence in NanoscienceiChEM(Collaborative Innovation Center of Chemistry for Energy Materials)University of Science and Technology of ChinaHefei 230026China Institute of Energy Hefei Comprehensive National Science CenterHefei 230026China Department of Chemical and Biological Engineering University at BuffaloThe State University of New YorkBuffaloNY 14260USA Materials Science and Engineering Mechanical EngineeringTexas Materials InstituteUniversity of Texas at AustinAustinTX 78712USA

Electrocatalysis is one type of *** catalysts at the electrode/electrolyte interfaces can facilitate electrochemical reactions with high rates and stability via selective pathways at potentials close to their thermodynamic limits(i.e.,minimum overpotentials).The first elaborated study for electrocatalysis can be dated back to the 1920s when Bowden and Rideal examined the electrolytic behaviors of a series of metal films for hydrogen ***,it is not until 1963 that Grubb used the word“electrocatalysis”for the first time to name the electrochemical processes in fuel cells.

关键词： electrocatalysis electrolyte electrolytic