On the Preparation of Potassium Carbonate and Magnesium Carbonate from Bittern (Part 3)

Abstract

Na₂CO, NaHCO₃and their mixture, which were added to the carnallite solution, converted MgCl₂into MgCO₃·3H₂O, and from this solution the Engel salt was deposited by carbonatation. The most suitable amount of the salts for the precipitation of the Engel salt was investigated. To get the product of good quality, the suitable amounts Na₂CO₃and NaHCO₃were 1.5-1.2 times equivalents of the content of MgCl₂in the carnallite, but their yields were 70%-50%. When NaHCO₃was used, the carbonatation process was not needed for the precipitation of Engel salt, but the yields ware very bad (below 50%). The mixture of Na₂CO₃and NaHCO₃could get the best results in the purity of the product and the yield of potassium.