THE CEMENTATION OF LEAD FROM AMMONIACAL AMMONIUM-SULFATE SOLUTION

Due to increasingly stringent SO2 emissions legislation, there have be en numerous research efforts to find a hydrometallurgical replacement for lead-acid battery smelter recycling operations. One promising poss ibility is the use of ammoniacal ammonium sulphate (AAS) solution to d issolve the lead sulphate found in used battery pastes. This paper exa mines the possibility of recovering metallic Pb from AAS solution via cementation, using Ni powder as the reductant. The highest recovery ra tes were achieved with high (17 mol/l) ammonium hydroxide and moderate (2 mol/l) ammonium sulphate concentrations. Below 135 degrees C, reac tion kinetics are rate-controlling and above 135 degrees C, diffusion is rate-controlling. (C) 1998 Elsevier Science B.V.