Abstract: Using the industrial wet-process phosphoric acid and potassium chloride as raw materials，the preparation of potassium dihydrogen phosphate by solvent extraction process was studied.The triotylamine-isoamyl alcohol was employed as the organic extracting agent.The influences of the ratio of organic and aqueous phases，reaction time，reaction temperature，and recycle numbers on the preparation of potassium dihydrogen phosphate were investigated.The results showed that the optimal operation parameters were as follows：the ratio of triotylamine to isoamyl alcohol was 1∶1，the reaction temperature was 20 ℃ and the reaction time was 60 min.The potassium dihydrogen phosphate product′s yield was above 95% and the purity was above 98% under the optimum conditions.This method is of high product purity，low extraction temperature，and simple operation etc..

Key words:  , phosphoric acid；KCl；solvent extraction；potassium dihydrogen phosphate