Recovery of cupric sulphate from spent etching solns. - by precipitating cupric oxide and dissolving in sulphuric acid

摘要

Cupric sulphte is recovered from spent etching solns. (in mfr. of printed circuits) by a process comprising: (a) oxidation of Cu+ ions (if present) to Cu2+ with H2O2; (b) precipitation of CuO with an alkali hydroxide soln.; (c) sepn. of CuO by filtration; and (d) reaction between CuO and H2SO4 to produce CuSO4. High purity solns. (after simple purification, if necessary) are obtained; they can be re-used in the prodn. of electric lead plates by the subtractive or additive technique, or in other chemical or electrochemical copper-deposition processes.