The influence of microwave calcination technological parameters on dechlorination of zinc-containing materials

Waelz-oxide is a zinc-containing material for the production of metallic zinc. Waelz-oxide should be pretreated to remove chlorides. Microwave heating and calcination of zinc-containing materials by an electromagnetic field of ultrahigh frequency is a promising method in metallurgy. In laboratory conditions, the microwave process of calcining zinc-containing materials (an analog of Waelz oxide) was investigated using the method of mathematical planning of experiments. The effect of power of microwave radiation, duration of the calcination process, and initial mass of the sample on the efficiency of chloride ion removal from the zinc-containing material has been studied. The optimum conditions are the following: power of microwave oven - 1400 W, processing time - 600 seconds and initial sample weight - 20 grams. Under the indicated process conditions, the residual content of chloride ion in the calcined product was 0.05 wt.%.