A method for the production of potassium sulfate by reaction of potash magn ia with chlorine, potassium solution

摘要

Mfr. of potassium sulphate from kieserite and KCL via potassium magnesium sulphate by a six-stage process, as follows: (1) KCL aq. (330-360 g/l) in major proportion from feedstock KCL (60% K2O) and in minor proportion from KCL (60% K2O) recycled from stage 4, is reacted with potassium magnesium sulphate from stages 2 and 3 to yield potassium sulphate and mother liquor, the potassium sulphate being sepd. (2) 85-90% of mother liquor from 1 is reacted withf finely ground kieserite. (3) 15-10% of mother liquor from 1 and water is reacted with langbeinite from stage 5. - (4) Salt from the vacuum evaporation (stage 6) is reacted cold with mother liquor from 2 and 3, producing KCL (60% K2o) which is recycled to stage 1. (5) The mother liquor from 4 contg. 230-250 g/l MgCl2 is evpoarated at 120-145 degrees C. (25-30 wt.%) with prodn. of langbeinite (recycled to 3) and hot mother liquor which (6) is vacuum cooled, removing 5-10% H2O to yield evaporator salt recycled to 4 and mother liquor contg. 360-460 g/l MgCl2 which is discarded.