Abstract: A new technology for producing potassium dihydrogen phosphate with calcium hydrophosphate and potassium hydrogen sulfate was introduced.Influences of amount-of-substance ratio of calcium hydrophosphate to potassium hydrogen sulfate,reaction temperature,volume ratio of liquid to solid,and reaction time were investigated by single factor experiments and optimal process conditions were obtained as follows:amount-of-substance ratio of calcium hydrophosphate to potassium hydrogen sulfate was 0.8 ∶1,reaction temperature was 70 ℃,volume ratio of liquid to solid was 4 ∶1,and reaction time was 120 min.Under the above conditions,experiment was taken to confirm that P₂O₅ recovery exceeded 89% and K₂O recovery exceeded 99%.Residuce was analyzed by XRD,and result verified that the composition of residuce was CaSO₄,without syngenite.Features of this method were characterized by simple operation,low cost,and high yield etc.   

Key words: potassium dihydrogen phosphate (MKP), potassium hydrogen sulfate, calcium hydrophosphate