METHOD FOR THE PRODUCTION OF POTASSIUM SULFATE FROM POTASSIUM-CONTAINING DOUBLE SALTS OF MAGNESIUM SULFATE

摘要

Essentially pure schoenite is leached to produce potassium sulfate and a sulfate leach liquor. The sulfate leach liquor is then brought into contact with a crystal crop predominating in potassium-containing double salts of magnesium sulfate. The quantity of double salt mixed with the leach liquor is limited to that which nearly saturates the liquor with respect to sodium chloride. There results a slurry of essentially pure schoenite in schoenite-conversion end liquor. The schoenite is recycled to the leaching step, and the conversion end liquor is recycled to a solar pond system wherein the potassium values remaining in the conversion end liquor are recovered.