Manganese recovery from electric arc furnace dust bioleachate: Evaluation of different precipitation agents.

This study optimized a one-step precipitation process for manganese recovery from a complex medium-bioleachate obtained from electric arc furnace dust (EAFD). The effects of pH variations and different precipitation agents, including acetone, ethanol, oxalic acid, and ammonium hydroxide, were investigated for manganese recovery. While acetone and ethanol facilitated precipitation, they did not lead to the formation of a specific manganese precipitate. The presence of other metals in the precipitate further reduced the purity of manganese precipitation. Oxalic acid proved ineffective in forming manganese precipitate from the citrate-based bioleachate. However, ammonium hydroxide demonstrated superior performance at pH 9.3 due to its lower affinity for manganese than other metals. Ammonium hydroxide precipitated 60% of manganese with 62% purity in a single step. Species diagrams simulated by MEDUSA software predicted MnHPO4 formation in the precipitate. Advanced analytical techniques (ICP, XRF, FTIR, FE-SEM, and EDX-mapping) were employed for comprehensive precipitate analysis.