Wet process of low environmental impact recovers the lead content of an
electrode slime and/or of lead minerals in the valuable form of high
purity-lead carbonates that are convertible to highly pure lead oxide by
heat treatment in oven at relatively low temperature, perfectly suited
for making active electrode pastes of new batteries or other uses. The
process basically comprises the following steps: a) adding sulphuric acid
to a different acid leach suspension of the starting impure material for
converting all dissolved lead compounds to insoluble lead sulphate; b)
separating the solid phase constituted by lead sulphate and undissolved
impurities from the acid leach solution; c) selectively dissolving lead
sulphate contained in said separated solid phase in an aqueous solution
of a lead solubilizing compound comprising preferably sodium acetate; d)
separating the solution containing dissolved lead sulphate from the solid
phase residue including undissolved impurities; e) adding to the
separated solution of lead sulphate a carbonate of the same cation of
said dissolving compound for forming insoluble lead carbonate and/or and
lead oxycarbonate and a dissolved sulphate of the same cation; f)
separating the precipitated carbonate and/or oxycarbonate of lead from
the dissolving solution now containing also sulphate of the cation of
said solubilizing compound.