常压酸化法制备硫酸钙晶须工艺研究

摘要

Decomposing phosphate rock with nitric acid,and phosphoric acid solution as the acid soluble medium to prepare calcium sulfate whiskers.The preparation conditions of calcium sulfate whiskers were mainly studied,and the influences of mass fraction of phosphoric acid,reaction temperature,mass fraction of sulfuric acid,and stirring speed on the aspect ratio of calcium sulfate whiskers were also investigated.The composition and morphology of calcium sulfate whiskers were characterized by differential thermal analysis and biological microscope analysis.The optimum technological conditions for preparation of calcium sulfate whiskers were confirmed by single element and orthogonal experiments:mass fraction of phosphoric acid was 35％,temperature was 95 ℃,stirring speed was 300 r/min,and mass fraction of sulfuric was 60％.The length-diameter ratio of the calcium sulfate whiskers reached 90 prepared under those conditions and the color was white.%用硝酸分解磷矿,以磷酸作为酸溶介质制备硫酸钙晶须.主要研究了硫酸钙晶须的制备工艺条件,考察了磷酸质量分数、反应温度、搅拌转速、硫酸质量分数对硫酸钙晶须长径比的影响.采用差热分析和生物显微镜分析了硫酸钙晶须的相组成和形貌.通过单因素实验和正交实验确定了制备硫酸钙晶须的最佳工艺条件:磷酸质量分数为35％、反应温度为95℃、搅拌转速为300 r/min、硫酸质量分数为60％.此条件下制得硫酸钙晶须长径比达到90,且颜色洁白.