The role of trivalent antimony was investigated in removing As, Sb, and Bi impurities from a copper electrolyte. Puri- fication experiments were carried out by adding a various concentrations of Sb（III） ions in a sy...The role of trivalent antimony was investigated in removing As, Sb, and Bi impurities from a copper electrolyte. Puri- fication experiments were carried out by adding a various concentrations of Sb（III） ions in a synthetic electrolyte containing 185 g/L sulfuric acid, 45 g/L Cu2＋, 10 g/L As, and 0.5 g/L Bi under stirring at 65℃ for 2 h. The electrolyte was filtered, and the structure, morphology and composition of the precipitate were analyzed by means of chemical analysis, scanning electron mi- croscopy （SEM）, X-ray diffraction （XRD）, transmission electron microscopy （TEM）, and IR spectroscopy. The precipitate is composed of irregular lumps which are agglomerated by fine dendritic and floccus particles, and it mainly consists of As, Sb, Bi, and O elements. Characteristic bands in the IR spectra of the precipitate are As-OX （X=As, Sb, Bi）, Sb-OY （Y=Sb, Bi）, O-As-O1 As-OH, Sb-OH, and O-H. The precipitate is a mixture of microcrystalline SbAsQ, （Sb,As）203, and amorphous phases. As, Sb, and Bi impurities are effectively removed from the copper electrolyte by Sb（III） ions attributing to these pre- cipitates.展开更多
The effects of additives on the stannous reduction of an acid sulfate bath were investigated using cyclic and linear sweep voltammetry, electrochemical impedance spectroscopy （EIS）, and microstructure analysis. In t...The effects of additives on the stannous reduction of an acid sulfate bath were investigated using cyclic and linear sweep voltammetry, electrochemical impedance spectroscopy （EIS）, and microstructure analysis. In the absence of additives, tin coatings are rough, and the tin electrodepositing is a single-step reduction process accompanied by hydrogen gas evolution. The addition of tartaric acid produces a slight reduction in the peak current of stannous reduction and has an appreciably positive effect on the stability of the acidic tin bath. Both benzylidene acetone and polyoxyethylene octylphenol ether hinder the stannous reduction and greatly suppress the hydrogen gas evolution. Formaldehyde slightly decreases the peak current density of stannous reduction and serves as an auxiliary brightener in the acid sulfate bath. The presence of mixed additives greatly suppresses the stannous reduction and hydrogen gas evolution and consequently produces a significantly smoother and denser tin coating. The （112） crystal face is found to be the dominant and preferred orientation of tin deposits.展开更多
An effective process for recycling lead from hazardous waste cathode ray tubes（CRTs） funnel glass through traditional lead smelting has been presented previously. The viscous behavior of the molten high lead slag, w...An effective process for recycling lead from hazardous waste cathode ray tubes（CRTs） funnel glass through traditional lead smelting has been presented previously. The viscous behavior of the molten high lead slag, which is affected by the addition of funnel glass, plays a critical role in determining the production efficiency. Therefore, the viscosities of the CaO–SiO_2–＂FeO＂–12wt%ZnO–3wt%Al_2O_3 slags were measured in the current study using the rotating spindle method. The slag viscosity decreases as the CaO/SiO_2 mass ratio is increased from 0.8 to 1.2 and also as the FeO content is increased from 8wt% to 20wt%. The breaking temperature of the slag is lowered substantially by the addition of FeO, whereas the influence of the CaO/SiO_2 mass ratio on the breaking temperature is complex. The structural analysis of quenched slags using Fourier transform infrared（FTIR） spectroscopy and Raman spectroscopy reveals that the silicate network structure is depolymerized with increasing CaO/SiO_2 mass ratio or increasing FeO content. The [FeO_6]-octahedra in the slag melt increase as the CaO/SiO_2 mass ratio or the FeO content increases. This increase can further decrease the degree of polymerization（DOP） of the slag. Furthermore, the activation energy for viscous flow decreases both with increasing CaO/SiO_2 mass ratio and increasing FeO content.展开更多
基金support by the National Natural Scientific Foundation of China(No. 50904023)the Natural Science Research Project of the Education Department of Henan Province (No.2010B450001)+1 种基金the Innovation Scientists and Technicians Troop Construction Projects of Henan Province(No. 104100510005)the Basic and Frontier Technologies Research Projects of Henan Province, China(No. 092300410064)
文摘The role of trivalent antimony was investigated in removing As, Sb, and Bi impurities from a copper electrolyte. Puri- fication experiments were carried out by adding a various concentrations of Sb（III） ions in a synthetic electrolyte containing 185 g/L sulfuric acid, 45 g/L Cu2＋, 10 g/L As, and 0.5 g/L Bi under stirring at 65℃ for 2 h. The electrolyte was filtered, and the structure, morphology and composition of the precipitate were analyzed by means of chemical analysis, scanning electron mi- croscopy （SEM）, X-ray diffraction （XRD）, transmission electron microscopy （TEM）, and IR spectroscopy. The precipitate is composed of irregular lumps which are agglomerated by fine dendritic and floccus particles, and it mainly consists of As, Sb, Bi, and O elements. Characteristic bands in the IR spectra of the precipitate are As-OX （X=As, Sb, Bi）, Sb-OY （Y=Sb, Bi）, O-As-O1 As-OH, Sb-OH, and O-H. The precipitate is a mixture of microcrystalline SbAsQ, （Sb,As）203, and amorphous phases. As, Sb, and Bi impurities are effectively removed from the copper electrolyte by Sb（III） ions attributing to these pre- cipitates.
基金supported by the National Natural Science Foundation of China(No.50904023)the Natural Science Research Project of the Education Department of Henan Province(No.2010B450001)+1 种基金the Innovation Scientists and Technicians Troop Construction Projects of Henan Province(No.104100510005)the Basic and Frontier Technologies Research Projects of Henan Province,China(No.092300410064)
文摘The effects of additives on the stannous reduction of an acid sulfate bath were investigated using cyclic and linear sweep voltammetry, electrochemical impedance spectroscopy （EIS）, and microstructure analysis. In the absence of additives, tin coatings are rough, and the tin electrodepositing is a single-step reduction process accompanied by hydrogen gas evolution. The addition of tartaric acid produces a slight reduction in the peak current of stannous reduction and has an appreciably positive effect on the stability of the acidic tin bath. Both benzylidene acetone and polyoxyethylene octylphenol ether hinder the stannous reduction and greatly suppress the hydrogen gas evolution. Formaldehyde slightly decreases the peak current density of stannous reduction and serves as an auxiliary brightener in the acid sulfate bath. The presence of mixed additives greatly suppresses the stannous reduction and hydrogen gas evolution and consequently produces a significantly smoother and denser tin coating. The （112） crystal face is found to be the dominant and preferred orientation of tin deposits.
基金financially supported by the National Natural Science Foundation of China (Nos. 51374066 and 51304047)the National Key Technologies R&D Program (No. 2014BAC03B07)the Industrial Research Projects in Liaoning Province, China (Nos. 2012223002 and 2014020037)
文摘An effective process for recycling lead from hazardous waste cathode ray tubes（CRTs） funnel glass through traditional lead smelting has been presented previously. The viscous behavior of the molten high lead slag, which is affected by the addition of funnel glass, plays a critical role in determining the production efficiency. Therefore, the viscosities of the CaO–SiO_2–＂FeO＂–12wt%ZnO–3wt%Al_2O_3 slags were measured in the current study using the rotating spindle method. The slag viscosity decreases as the CaO/SiO_2 mass ratio is increased from 0.8 to 1.2 and also as the FeO content is increased from 8wt% to 20wt%. The breaking temperature of the slag is lowered substantially by the addition of FeO, whereas the influence of the CaO/SiO_2 mass ratio on the breaking temperature is complex. The structural analysis of quenched slags using Fourier transform infrared（FTIR） spectroscopy and Raman spectroscopy reveals that the silicate network structure is depolymerized with increasing CaO/SiO_2 mass ratio or increasing FeO content. The [FeO_6]-octahedra in the slag melt increase as the CaO/SiO_2 mass ratio or the FeO content increases. This increase can further decrease the degree of polymerization（DOP） of the slag. Furthermore, the activation energy for viscous flow decreases both with increasing CaO/SiO_2 mass ratio and increasing FeO content.
