Study on process of smelting antimony using bismuth refining dust as raw material.

A process is described for the extraction of Sb from As-containing Bi refining dust involving hydrochloric acid leaching, hydrolysis, conversion and reduction smelting. Optimum leaching conditions were a solid/liquid ratio of 1:3, reaction time of 4 h, reaction temperature of 80 degrees C and a hydrochloric acid dosage of 1.2 times theoretical. Sb leaching rates of up to 99.5% were achieved. Antimony oxychloride was obtained by hydrolysis using a hydrochloric acid solution with a dilution ratio of 10:1 and a temperature of 25 degrees C for 1 h. The antimony oxychloride was converted to antimony trioxide with 90.76% purity using 1.2 times the theoretical amount of aqueous ammonia at a solid/liquid ratio of 1:1.6 and a reaction temperature of 25 degrees C for 1 h. Optimum conditions for the reduction smelting of antimony trioxide were a temperature of 1 100 degrees C, reaction time of 45 min and dosages of anthracite coal reductant and sodium carbonate fluxing agent equivalent to 4.9 and 4.32 wt%, respectively. The product contained 99.04% Sb and the direct recovery of Sb was 93.2%.
A process is described for the extraction of Sb from As-containing Bi refining dust involving hydrochloric acid leaching, hydrolysis, conversion and reduction smelting. Optimum leaching conditions were a solid/liquid ratio of 1:3, reaction time of 4 h, reaction temperature of 80 degrees C and a hydrochloric acid dosage of 1.2 times theoretical. Sb leaching rates of up to 99.5% were achieved. Antimony oxychloride was obtained by hydrolysis using a hydrochloric acid solution with a dilution ratio of 10:1 and a temperature of 25 degrees C for 1 h. The antimony oxychloride was converted to antimony trioxide with 90.76% purity using 1.2 times the theoretical amount of aqueous ammonia at a solid/liquid ratio of 1:1.6 and a reaction temperature of 25 degrees C for 1 h. Optimum conditions for the reduction smelting of antimony trioxide were a temperature of 1 100 degrees C, reaction time of 45 min and dosages of anthracite coal reductant and sodium carbonate fluxing agent equivalent to 4.9 and 4.32 wt%, respectively. The product contained 99.04% Sb and the direct recovery of Sb was 93.2%.