关键词: 湿法磷酸, 氧化-沉淀, 净化

Abstract: In order to make decoloration and to remove iron and aluminum ions for wet-process phosphoric acid,the method of oxidation and deposition was used to purify wet-process phosphoric acid.Firstly,a certain amount of hydrogen peroxide was added for decoloration of wet-process phosphoric acid,and then a certain amount of precipitator potassium oxalate and precipitation assistant sodium carbonate were added for removing iron and aluminum ions.With single factor experiments,the best technological conditions of purifying wet-process phosphoric acid were obtained as follows:decolored rate could reach above 95%,and the purification rates of iron and aluminum could reach 47.51% and 9.30% respectively when the temperature was 45 ℃,amount of hydrogen peroxide was 1%(volume fraction),dosage of potassium oxalate was 0.5%(mass fraction),dosage of sodium carbonate was 0.3%(mass fraction),and the time was 12 h.

Key words: wet-process phosphoric acid, oxidation and precipitation, purification