A novel process for efficient and selective recovery of potassium from phosphorus electrostatic precipitator dust using ionic liquids

As a waste product of phosphorus production, phosphorus electrostatic precipitator (ESP) dust contains approximately 14% potassium and is a potential resource for potassium recovery. In this study, we aimed to extract potassium from phosphorus ESP dust using a novel approach based on ionic liquid. To achieve this goal, we constructed the leaching-extraction-electrodeposition process based ionic liquid, which allowed for the efficient extraction of potassium. We determined the occurrence of potassium in ESP dust and found that under optimal conditions with electro-field enhancement, the recovery rate of potassium was 95.37%, the leaching process was found to fit the mixed control model well. We obtained a maximum extraction amount of 452.256 mg/L in the extraction section. Importantly, both the leaching and extraction processes exhibited high selectivity for potassium, indicating their potential for targeted potassium recovery from ESP dust. To verify the feasibility of the electrodeposition of potassium, we conducted additional experiments and found that our method was capable of recovering potassium via electrodeposition, further highlighting the potential of this approach. Overall, our study demonstrates a novel and environmentally friendly method for potassium recovery from phosphorus ESP dust, with high efficiency and selectivity, and contributes to the growing body of research on sustainable resource utilization. •New process for leaching-extraction-electrodeposition of potassium by ionic liquids.•An electric field to enhance leaching and selective while reducing leaching time.•The feasibility of electrodeposition of potassium in ionic liquids was verified.