High Sulfur Bauxite Dissolution Behavior And Anti-flotation Desulfurization

There are abundant resources of sulfur-containing bauxite in our country. The resource of sulfur-containing bauxite is 0.15 billion ton, accounting for 11.0% of total bauxite resources in China. With rapid increase of alumina production high quality bauxite becomes more and more scarce. But there is still some sulfur-containing bauxite unused. It will reduce the burden of bauxite resource if we are able to utilize this kind of bauxite efficiently.This paper studied the digestion of sulfur containing bauxite and the effect of sulfur on the Bayer process. Flotation method was used to remove sulfur from bauxite so that bauxite concentrate with low sulfur content was obtained which can be treated by Bayer process.Guangxi bauxite containing low amount of sulfur was mixed with Guangxi bauxite with high sulfur content and was then digested. By means of X-ray diffraction analysis, atom adsorption analysis and chemical analysis, effect of sulfur on alumina digestion efficiency,concentration of iron and concentration of S^2- in aluminate solution were researched. The result showed: Sulfur content had no effect on alumina digestion yield; high amount of sulfur would lead to more sulfur entering solution. With the increase of sulfur in bauxite, iron and S^2- concentration in aluminate solution rise significantly.Flotation research had been carried out on Henan bauxite based on reviewing relevant literature of reverse flotation of bauxite.Reverse floatation was conducted in which butly xanthate and amyl xanthate was used as collector, Na₂CO₃ as pH regulator, (NaPO₃)₆ as dispersant, Na₂S and CuSO₄ as activator. The final result showed the recovery of flotation concentrate was 97.46% with sulfur content of 0.27%. The recovery of sulfur reached 72.65% in the tailing bauxite with sulfur content of 27.44%. The flotation concentrate had good digestion properties.