An anion-exchange-based chromatographic separation approach was developed to selectively recover zinc and copper from the high-chlorine raffinate generated in the process of germanium chlorination distillation using 7...An anion-exchange-based chromatographic separation approach was developed to selectively recover zinc and copper from the high-chlorine raffinate generated in the process of germanium chlorination distillation using 717 resins based on the coordination difference between Zn^(2+)/Cu^(2+)and Cl^(-).The theoretical calculation and spectroscopic analyses suggested that the coordination between Zn^(2+)and Cl^(-)is much stronger than that between Cu^(2+)and Cl^(-),and the Cl-concentration significantly affects Zn(Ⅱ)and Cu(Ⅱ)species.The factors involving Cl-concentration,resin dosage,shaking speed,and temperature were investigated to determine the optimal condition,and the maximum separation factor of Zn/Cu reached as high as 479.2.The results of the adsorption isotherms,adsorption kinetics,SEM,FTIR,and XPS analyses indicated that the process followed the monolayer uniform chemisorption.Through the continuous adsorption experiments,Zn(Ⅱ)and Cu(Ⅱ)in the high-chlorine raffinate were separately recovered,allowing the reuse of residual waste acid and germanium.展开更多
A novel process was developed to produce spherical copper powder for multilayer ceramic capacitors （MLCC）. Spherical ultrafine cuprous oxide （Cu20） powder was prepared by glucose reduction of Cu（OH）2. The Cu20 p...A novel process was developed to produce spherical copper powder for multilayer ceramic capacitors （MLCC）. Spherical ultrafine cuprous oxide （Cu20） powder was prepared by glucose reduction of Cu（OH）2. The Cu20 particles were coated by Mg（OH）2 and reduced to metallic copper particles. At last, the copper particles were densified by high-temperature heat treatment. The products were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, tap density, and thermogravimetry （TG）. It is found that the shape and size distribution of the copper powder are determined by the Cu20 powder and the copper particles do not agglomerate during high-temperature heat treatment because of the existence of Mg（OH）2 coating. After densification at high temperature, the particle tap density increases from 3.30 to 4.18 g/cm3 and the initial oxidation temperature rises from 125 to 150~C.展开更多
基金financially supported by the Postdoctoral Research Foundation of Central South University,China(No.140050037)。
文摘An anion-exchange-based chromatographic separation approach was developed to selectively recover zinc and copper from the high-chlorine raffinate generated in the process of germanium chlorination distillation using 717 resins based on the coordination difference between Zn^(2+)/Cu^(2+)and Cl^(-).The theoretical calculation and spectroscopic analyses suggested that the coordination between Zn^(2+)and Cl^(-)is much stronger than that between Cu^(2+)and Cl^(-),and the Cl-concentration significantly affects Zn(Ⅱ)and Cu(Ⅱ)species.The factors involving Cl-concentration,resin dosage,shaking speed,and temperature were investigated to determine the optimal condition,and the maximum separation factor of Zn/Cu reached as high as 479.2.The results of the adsorption isotherms,adsorption kinetics,SEM,FTIR,and XPS analyses indicated that the process followed the monolayer uniform chemisorption.Through the continuous adsorption experiments,Zn(Ⅱ)and Cu(Ⅱ)in the high-chlorine raffinate were separately recovered,allowing the reuse of residual waste acid and germanium.
文摘A novel process was developed to produce spherical copper powder for multilayer ceramic capacitors （MLCC）. Spherical ultrafine cuprous oxide （Cu20） powder was prepared by glucose reduction of Cu（OH）2. The Cu20 particles were coated by Mg（OH）2 and reduced to metallic copper particles. At last, the copper particles were densified by high-temperature heat treatment. The products were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, tap density, and thermogravimetry （TG）. It is found that the shape and size distribution of the copper powder are determined by the Cu20 powder and the copper particles do not agglomerate during high-temperature heat treatment because of the existence of Mg（OH）2 coating. After densification at high temperature, the particle tap density increases from 3.30 to 4.18 g/cm3 and the initial oxidation temperature rises from 125 to 150~C.
