The dissolution kinetics of gold and silver cyanidation of Cu-Au sulfide concentrate has been investigated at ambient temperature in consideration of effects of various parameters,such as particle size of ores,hydrody...The dissolution kinetics of gold and silver cyanidation of Cu-Au sulfide concentrate has been investigated at ambient temperature in consideration of effects of various parameters,such as particle size of ores,hydrodyna.mics of the process and initial cyanide concentration as well as oxygen partial pressure.The experimental data are mathematically treated with an approach based on the shrinking core model.A phenomenological expression describing the rate and rate constants for cyanidation of the concentrate is developed from the treatment.The dissolution of gold and silver is explained by an electrochemical mechanism in which the rate determining step is,the diffusion of cyanide and dissolved molecular oxygen through a porous layer formed during the minerals dis-solutions.展开更多
A cyanidation leaching process for a sulfide concentrate containing gold and silver with ammonia and other complexes was investigated,and its potential in decrease of cyanide consumption was examined.The equilibria be...A cyanidation leaching process for a sulfide concentrate containing gold and silver with ammonia and other complexes was investigated,and its potential in decrease of cyanide consumption was examined.The equilibria behaviors of copper and other metal ions in the CN-NH,-H_(2)0 system and the CN—NH,—EDTA-HjO system were analyzed by a microcomputer program.Experiments revealed that the leaching yield of gold in ammonia-cyanide solutions was raised from 86%to 99%from addition of EDTA in a certain concentration and its cooperative action with ammonia on the cyanidation of gold.Meanwhile,the leaching yield of silver was significantly increased from about 20%to 55%and the consumption of cyanide was decreased.展开更多
The optimum operating conditions for the electrodeposition of nickel from all-nickel chloride electrolytes were studied,based on measurements of conductivity,surface tension,viscosity of nickel chloride electrolytes a...The optimum operating conditions for the electrodeposition of nickel from all-nickel chloride electrolytes were studied,based on measurements of conductivity,surface tension,viscosity of nickel chloride electrolytes at different temperatures and concentrations of nickel chloride as well as the experiments of electrodeposition arranged using experimental design in the normal table.Through studying cathode polarization and examination of physical features of cathodic nickel,the effects of trace Fe,Co,Pb..TBP and N-235 in all-nickel chloride electrolyte on cathode potentials,cell voltages,current efficiency and energy consumption as well as the morphology and the internal stress of cathodic nickel in electrodeposition of nickel were examined.展开更多
文摘The dissolution kinetics of gold and silver cyanidation of Cu-Au sulfide concentrate has been investigated at ambient temperature in consideration of effects of various parameters,such as particle size of ores,hydrodyna.mics of the process and initial cyanide concentration as well as oxygen partial pressure.The experimental data are mathematically treated with an approach based on the shrinking core model.A phenomenological expression describing the rate and rate constants for cyanidation of the concentrate is developed from the treatment.The dissolution of gold and silver is explained by an electrochemical mechanism in which the rate determining step is,the diffusion of cyanide and dissolved molecular oxygen through a porous layer formed during the minerals dis-solutions.
文摘A cyanidation leaching process for a sulfide concentrate containing gold and silver with ammonia and other complexes was investigated,and its potential in decrease of cyanide consumption was examined.The equilibria behaviors of copper and other metal ions in the CN-NH,-H_(2)0 system and the CN—NH,—EDTA-HjO system were analyzed by a microcomputer program.Experiments revealed that the leaching yield of gold in ammonia-cyanide solutions was raised from 86%to 99%from addition of EDTA in a certain concentration and its cooperative action with ammonia on the cyanidation of gold.Meanwhile,the leaching yield of silver was significantly increased from about 20%to 55%and the consumption of cyanide was decreased.
文摘The optimum operating conditions for the electrodeposition of nickel from all-nickel chloride electrolytes were studied,based on measurements of conductivity,surface tension,viscosity of nickel chloride electrolytes at different temperatures and concentrations of nickel chloride as well as the experiments of electrodeposition arranged using experimental design in the normal table.Through studying cathode polarization and examination of physical features of cathodic nickel,the effects of trace Fe,Co,Pb..TBP and N-235 in all-nickel chloride electrolyte on cathode potentials,cell voltages,current efficiency and energy consumption as well as the morphology and the internal stress of cathodic nickel in electrodeposition of nickel were examined.
