Regeneration of manganese electrolyte during continuous electrolysis of manganese coatings

Abstract

Water pollution in the electrolytic manganese metal (EMM) industrial production process is a serious problem, and the manganese and ammonia nitrogen concentration in the rivers near EMM plants still exceeds the standards. An environment-friendly regeneration method of the manganese electrolyte (ME) that reduces the duration of the electrodeposition process and saves water resources for ME preparation in laboratories was proposed. Thus, electrolytic manganese metal powder (EMMP) was dissolved in ME and the addition of hydroxylamine sulphate altered significantly the dissolution effect of EMMP in ME. The provided ME regeneration scheme allows to extend duration of the Mn coating deposition process up to one week without changing ME, just only adding the electrolyte prepared by dissolving EMMP in an anolyte. EMMP losses did not exceed 5–7% from the mass of the electrodeposited Mn coatings on the cathode. Ammonium selenate was dissolved in ME by periodically dissolving 2% of the salt from the mass of the electrodeposited Mn coating on the cathode at an electrolyte temperature of 30–40°C.