Luo Q.,Kunming University of Science and Technology |
Luo Q.,Laboratory Breeding Base of Complex Non Ferrous Metal Resources Clear Utilization in Yunnan Province |
Luo Q.,Key Laboratory of Non Ferrous Metals Vacuum Metallurgy of Yunnan Province |
Qu T.,Kunming University of Science and Technology |
And 14 more authors.
Zhenkong Kexue yu Jishu Xuebao/Journal of Vacuum Science and Technology | Year: 2012
We addressed the carbothermic reduction of the saprolite nickel laterite ore in vacuum. The microstructures and properties of the saprolite nickel laterite grains and the reduction products and the phase transformation involved were characterized with X-ray diffraction, scanning electron microscopy-energy dispersive spectroscopy. We found that roasting of saprolite nickel laterite at 973 K promoted decomposition and reduction of the minerals, possibly because of changes in its microstructures. The results show that the reduction mainly produced SiC, Fe-Si alloy, 2MgO·SiO2, Mg and the gaseous phased SiO. In the condensation area, SiO disproportionated into Si and SiO2; and Mg was slightly contaminated by O and Si. Moreover, addition of CaO and CaF2 considerably enhanced the carbothermic reduction and enrichment of ferronickel grains.
Li L.,Kunming University of Science and Technology |
Li L.,Laboratory Breeding Base of Complex Non Ferrous Metal Resources Clear Utilization in Yunnan Province |
Liu D.-C.,Kunming University of Science and Technology |
Liu D.-C.,Laboratory Breeding Base of Complex Non Ferrous Metal Resources Clear Utilization in Yunnan Province |
And 7 more authors.
Zhongnan Daxue Xuebao (Ziran Kexue Ban)/Journal of Central South University (Science and Technology) | Year: 2012
The volatilization behavior of metals from silver-contained lead-antimony multi-component alloys was investigated by vacuum distillation process for the enrichment of silver under the condition of medium vacuum. The effects of distillation temperature, distillation time on metals' removal rate were examined. Experimental results demonstrate that the removal rate of Bi and Pb is close to 100% at 950°C for more than 45 min when the system pressure is 5 to 25 Pa, and more than 96.3% As and 92.5% Sb are volatilized although the results are not very ideal. Ag and Cu are basically non-volatile under the same conditions. XRD analysis indicates that the residual copper, antimony, silver and arsenic are present in phases of Cu 2Sb, Cu 10Sb 3, Ag 3Sb and Cu 5As 2. This is the reason why antimony and arsenic can not be volatilized thoroughly. The vacuum distillation process provides a simple, clean and efficient way for the separation of silver and other metals which compose the lead anode slime with high antimony and low silver. And the silver enrichment is efficient by vacuum distillation.