OBSERVATIONS ON THE USE OF A HYDROGEN ANODE IN THE PRODUCTION OF ELECTROLYTIC MAGNESIUM

摘要

Most electrolytic magnesium metal production utilizes a magnesium oxide feed material. One process route requires hydrochloric acid for feed dissolution, which in turn requires cleaning, drying, compression and combustion with hydrogen of the chlorine gas produced in the electrowinning process. An alternative route utilizes the chlorine in the anhydrous reduction of MgO to MgCl2. Either operation constitutes a significant part of the capital investment and operating cost of an electrolytic magnesium facility. This work explores the concept of producing hydrogen chloride gas on the anode in molten salt electrowinning of magnesium metal, which in addition to offering capital savings can also lower the cell voltage by one (1) Volt compared to chlorine gas evolution. Experimental results and some observations on reduction to industrial practise are presented.