Reclamation of steel shots by acid leaching for powder metallurgy applications

Acid leaching is extensively employed for extractive metallurgy, but its use on reclamation of shot blasting media has not been extensively studied. The parameters of acid leaching process such as rate of stirring, the leached material grain size, the solid (material) to liquid (acid) ratio, type of acid, concentration of acid, leaching temperature, and leaching duration govern the effectiveness of this process. The goal of this article is to investigate the effectiveness of acid leaching to recover the iron from used shot blasting media. Influence of varying leaching durations on the recovery percentage of iron from the used shot blasting media is investigated, and it is found that acid leaching can remove impurities from used shot blasting media and it can successfully recover 73.6% of iron on the particle surface level and 44.3% of iron overall. Hence, it is a feasible process for recovery of iron from used shot blasting media.