Separation of Bismuth From a Bismuth Glance Concentrate Through a Low-Temperature Smelting Process

The present study aims to characterize and separate bismuth from a bismuth glance concentrate through a low-temperature sulfur-fixing smelting process. It reports on the effects of the optimization of process parameters such as sodium carbonate (Na2CO3) and zinc oxide (ZnO) weight percentage in charging, smelting temperature, and smelting duration on the bismuth yield and resultant crude bismuth grade. A maximum bismuth recovery rate of 97.31% and a crude bismuth grade of 96.93% are obtained when a charge (containing 63.5 wt% Na2CO3, 22.5 wt% bismuth glance, and 5% in excess of the stoichiometric requirement of ZnO dosage) is smelted at 900°C for 150 min. Based on the results of the chemical content analysis of separated ZnS, more than 93% ZnS can be recovered, and the recovered ZnS grade can reach 60.2%.