THE ELECTROLYSIS OF SOLUTIONS OF SULPHUR ACID SALTS OF COPPER AND ZINC IN THE PRESENCE OF INSOLUBLE LEAD BASED ANODES

Abstract

The process of electrical extraction electrolysis for the production of high-purity non-ferrous metals, in particular, the electrolysis of copper and zinc in hydrometallurgy has been investigated. Insoluble anodes based on lead play an important role. From acid solutions, metals with a positive standard reduction potential can be isolated. Copper is almost the only metal that is separated by cathode deposition. For the electrolysis of solutions sulphate salts of copper (II), a copper plate as a cathode is used. As a result, powder copper is produced by electro-extraction. Lead anodes doped with various s- p-elements were used as anodes. The electrolysis was carried out for 30 minutes in 3 stages each of the stages - 10 minutes, the total mass of copper - m = m1 + m2 + m3. For the electroextraction of copper, the lead anode containing 0,2% calcium is considered the best - m = 210 mg. The addition of the calcium s-element increases the anode resistance of lead. When using an anode of pure lead, m = 117 mg, and at a content of 1,7% Sb- m = 105 mg,

i.e. the total mass of copper decreases. With the alloy 4, containing 5% Sb- m = 199 mg, i.e. the copper mass increases, and with the alloy 6, containing 50% of the metal fraction and 50% of the oxide-sulphate fraction, m = 109 mg. However, m1 <m2 <m3, i.e. unlike other anodes, the mass of copper increases during electrolysis, and according to the data of our former experiments, the corrosion rate with both anodes increases dramatically.

In the multicomponent alloy 5, containing Pb, Sb and Bi, it is difficult to establish the effect of the elements on the anodic behavior of the electrodes (with lead), and between themselves. Therefore, in the technical electrolysis of copper (II), the use of anodes of alloys 4, 5, 6 is not recommended.

During the electrolysis of solutions of zinc sulphate salts, an aluminum plate was used as a cathode. For the electrical extraction of zinc, the pure lead anode is the best (m = 103 mg). However,zinc grows badly to the cathode and when washing the electrode, it partially goes into the solution. After filtration, the zinc residue is washed, dried, weighed and added to the bulk of zinc. Alloys 4 and 6 have not used as anodes.