大长径比硫酸钙晶须的制备及形貌研究

发布时间：2018-05-17 23:13

  本文选题：天然石膏 + 水热法　； 参考：《矿产保护与利用》2017年06期

【摘要】：以天然石膏为原料采用水热法制备半水硫酸钙晶须,SEM观察晶须形貌及分析长径比。考察了外加剂、原料粒度、水热温度、pH值、初始料浆浓度、水热时间对硫酸钙晶须形貌影响。结果表明:外加剂提高了天然石膏在水中的溶解度;原料粒度会影响天然石膏的溶解速率,粒度越小溶液越容易达到过饱和状态;水热温度在100℃时较难生成硫酸钙晶须;溶液pH值可改变溶液离子质量分数,随着pH值升高晶须平均直径逐渐减小,同时会导致外加剂失效;料浆浓度越高,晶须生长空间越小,溶液体系离子迁移速度降低。在原料粒度4μm、料浆浓度5%、CuCl_21.5%(相对于天然石膏质量)、水热温度120℃、pH=5.3、水热时间140 min的条件下,制备出平均直径1~2μm、长径比达160的半水硫酸钙晶须。
[Abstract]:Using natural gypsum as raw material, calcium sulfate semidihydrate whisker was prepared by hydrothermal method. SEM was used to observe the morphology of whisker and to analyze the aspect ratio. The effects of additives, particle size of raw materials, hydrothermal temperature and pH value, initial slurry concentration and hydrothermal time on the morphology of calcium sulfate whisker were investigated. The results show that the solubility of natural gypsum in water is improved by admixture, the dissolution rate of natural gypsum is affected by the particle size of raw material, the smaller the particle size is, the more easily the solution is supersaturated, the calcium sulfate whisker is difficult to be formed at the hydrothermal temperature of 100 鈩，

本文编号：1903297