A novel and clean technological route for the comprehensive utilization of low-grade ludwigite ore was proposed, inwhich magnesium was extracted by metallizing reduction?magnetic separation, sulfuric acid leaching an...A novel and clean technological route for the comprehensive utilization of low-grade ludwigite ore was proposed, inwhich magnesium was extracted by metallizing reduction?magnetic separation, sulfuric acid leaching and ethanol precipitationoperation. Meanwhile, iron-rich product, silicon-rich product and boron-rich product were obtained, respectively. In the process ofmetallizing reduction-magnetic separation, 94.6% of magnesium was enriched in the non-magnetic substance from the ore reducedat 1250 ℃ for 60 min with the ore size of 0.50-2.00 mm and coal size of 0.50-1.50 mm. When the non-magnetic substance wasleached at 90 ℃ for 15 min with the liquid-to-solid ratio of 7:1, 87.4% of magnesium was leached into the liquor separated fromsilicon gathering in leaching residue. The ethanol precipitation was conducted for 30 min with the ethanol-to-original liquid volumeratio of 1.5:1 at room temperature. 97.2% of magnesium was precipitated out with the initial concentration of 0.8 mol/L in the formof MgSO4·7H2O.展开更多
基金Project(20100042110004)supported by the Specialized Research Fund for the Doctoral Program of Higher Education of ChinaProjects(N090502004,N140206003)supported by Fundamental Research Funds for the Central University,China
文摘A novel and clean technological route for the comprehensive utilization of low-grade ludwigite ore was proposed, inwhich magnesium was extracted by metallizing reduction?magnetic separation, sulfuric acid leaching and ethanol precipitationoperation. Meanwhile, iron-rich product, silicon-rich product and boron-rich product were obtained, respectively. In the process ofmetallizing reduction-magnetic separation, 94.6% of magnesium was enriched in the non-magnetic substance from the ore reducedat 1250 ℃ for 60 min with the ore size of 0.50-2.00 mm and coal size of 0.50-1.50 mm. When the non-magnetic substance wasleached at 90 ℃ for 15 min with the liquid-to-solid ratio of 7:1, 87.4% of magnesium was leached into the liquor separated fromsilicon gathering in leaching residue. The ethanol precipitation was conducted for 30 min with the ethanol-to-original liquid volumeratio of 1.5:1 at room temperature. 97.2% of magnesium was precipitated out with the initial concentration of 0.8 mol/L in the formof MgSO4·7H2O.