关键词: 磷石膏;常压酸化法;硫酸钙晶须;晶型助长剂

Abstract: The phosphate gypsum was dissolved in sulfuric acid solution to remove the impurities and then the insoluble solid was dissolved in hydrochloric acid at normal pressure, the calcium in the phosphorus gypsum was enriched in the solution.The calcium sulfate whiskers were prepared by treating the solution.The effects of initial concentration of calcium sulfate, crystallization temperature, the types and amount of crystallization promoting agents on the content, structure and morphology of calcium sulfate whiskers were investigated.The results show that the whiskers are calcium sulfate dihydrate;Ethanol is the best crystallization promoting agent;The uniform whiskers with diameter of 25 μm, aspect ratio of about 80 is prepared when the amount of ethanol is 15 mL(Vethanol∶Vhydrochloric acid=1∶2).

Key words: phosphogypsum;atmospheric acidification method;calcium sulfate whisker;crystallization promoting agent