Selective leaching of copper and zinc from primary ores and secondary mineral residues using biogenic ammonia

With the number of easily accessible ores depleting, alternate primary and secondary sources are required to meet increasing demand economically important metals. Whilst highly abundant, these materials lower grade with respect traditional ores, thus selective sustainable metal extraction technologies needed reduce processing costs. Here, we investigated leaching potential biogenic ammonia produced by a ureolytic strain Lysinibacillus sphaericus on eight materials, comprised mining metallurgical residues, sludges automotive shredder residues (ASR). For majority moderate high yields (30–70%) very selectivity (>97% against iron) copper zinc were obtained 1 mol L−1 total ammonia. Optimal was achieved further refined for ASR in two-step indirect system Copper result local corrosion differences synthetic (NH4)2CO3 control could be accounted pH shifts from microbial metabolism, subsequently altering free NH3 coordination. These results provide findings future recovery materials.