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The main purpose of this study is to characterize and separate bismuth from a bismuth glance concentrate through a low-temperature sulfur-fixing smelting process.This paper reports on a study conducted on optimization of process parameters, such as Na2CO3 and zinc oxide weight percentage in charging, smelting temperature, smelting duration on the bismuth yield, resultant crude bismuth grade, and sulfur fixing rate.A maximum bismuth recovery of 97.31%, crude bismuth grade of 96.93%, and 98.23% sulfur fixing rate are obtained when a charge (containing 63.50 wt% of Na2CO3 and 22.50 wt% of bismuth glance, and 5% of the stoichiometric requirement of zinc oxide dosage) is smelted at 1000 K for 150 minutes.This smelting operation is free from atmospheric pollution because zinc oxide is used as the sulfur fixing agent, which can capture sulfur fi-om bismuth sulfide and forms more thermodynamic-stable compound zinc sulfide.The solid residue is subjected to mineral dressing operation to obtain suspension, which is filtered to ultimately produce a cake, representing the solid particles of zinc sulfide.Based on the results of the chemical content analysis of as-resultant zinc sulfide, more than 93% zinc sulfide can be recovered, and the recovered zinc sulfide grade can reach 60.20 %.This can be sold as zinc sulfide concentrate or roasted to regenerate into zinc oxide.