Applied research of hydrofluoric acid in puring wet-phosphoric acid

Using hydrofluoric acid and sodium carbonate as sediments,removal of metal impurities from WPA was studied.The effects of dosage of hydrofluoric acid and sodium carbornate,reaction time and temperature,stirring speed,static time on removal rate of aluminum,magnesium,iron from wet-phosphoric acid were also investigated.The results showed that,when reaction temperature was 40℃,stirring speed was 50 r/min,reaction time was 10 mins,dosage of hydrofluoric acid was 1.2 times,dosage of sodium carbonate was 0.2 times and static time was one day,the removal rate of aluminum,magnesium and iron were respectively 49.2%, 26.9% and 21.9%,and the recovery rate of phosphoric acid reached 90.7%.