The presence of volatile species, such as alkali halides and lead oxides, in electric arc furnace dust presents challenges for both pyrometallurgical and hydrometallurgical zinc recovery processes. This study proposes a low-pressure pretreatment method to remove these volatile species from electric arc furnace dust. In this method, the volatile compounds evaporate in a heated compartment within a virtually closed system under reduced pressure, while condensation occurs in a cooler compartment at a lower temperature. Thermodynamic calculations indicate that it is feasible to separate volatile species from those with lower vapor pressures at temperatures as low as 900 °C. Experimental results confirmed the successful removal of lead, potassium, and sodium compounds at this temperature, achieving removal amounts of 97.8%, 99.2%, and 82.4%, respectively. The study also examined the effects of various oxidizing and reducing additives, alongside different carrier gases. Key process parameters, including temperature, time, and pressure, were investigated and discussed.

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