Effect of Manganese and Arsenic upon Current Efficiency in the Deposition of Zinc from Zinc Sulphate Solution

Throughout the entire experiment the electrolysis were conducted in an eight-hundred cubic centimeter beaker. An excellent circulation of the solution was assured by means of an electric stirrer, vigorous gas evolution from the anodes, and by means of a regulated feed-discharge system. By means of this balance, solution of the same impurity concentration as that of the electrolyte was fed in the cell just as fast as the discharge was syphoned out.

The Effect of Cobalt Upon Current Efficiency in the Electrolysis of Zinc Sulphate Solutions

The detrimental effect of the presence of cobalt upon the current efficiency, in the commercial production of zinc by electrolysis, has been recognized for some time. Most authorities differ upon the maximum amount of cobalt allowable. This is due to the fact that the presence of other impurities either increases or diminishes the detrimental effects of the cobalt. The following tests were made with the object in view of ascertaining the relation, if any, between the amount of cobalt present and the current efficiency during the electrolysis of an otherwise pure zinc sulfate solution. The results obtained from these observations indicate that there is little apparent relation between the cobalt concentration of a given solution of zinc sulfate and the current efficiency that may be obtained on the electrolysis of that solution. For certain cobalt concentrations, however, it was noted that the time factor played an important part.

The Electrodeposition of Manganese from Certain Aqueous Solutions

Careful examination of the literature available shows that the electrodeposition of manganese from various aqueous solutions has not been attempted to any great extent. The best method for the electrodeposition of pure manganese consists in the electrolysis of a solution con­taining manganous and ammonium sulphates.