K_2SO_4/KCl添加剂对脱硫石膏晶须结晶的影响

Effect of K_2SO_4/KCl Additive on the Crystallization of Desulfurization Gypsum Whisker

以提纯后的脱硫石膏为原料,分别以K2SO4和KCl为添加剂,采用水热法制备了脱硫石膏晶须,研究了添加剂用量对晶须显微结构、长径比和溶液组成的影响,并探讨了其作用机理。研究结果表明:添加剂用量对晶须形貌影响较大,但并不影响其物相组成;当K2SO4、KCl用量分别为3%和5%时,制备的晶须结晶良好,长径比分别达80和50。加入K2SO4后,脱硫石膏在反应溶液中的溶解度减小,而加入KCl,其溶解度增大。强电解质离子K+的加入,促使晶须延c轴生长,从而使其长径比增大。

The whiskers were prepared by hydrothermal method Using purified desulfurization gypsum as raw materials, K2SO4 or KC1 as additive. The effect of K^SO4 or KC1 on the microstrueture and aspect ratio of whiskers and solution composition were investigated, as well as its mechanism was discussed. The results indicated that the content of K2SO4 or KC1 has an important effect on the morphology of whiskers, but no effect on its phase. When the content of KzSO4 or KC1 is 3% or 5%, respectively, the aspect ratio of whiskers with excellent crystallization is about 80 and 50. As the K2SO4 added into solution, the solubility of desulfurization gypsum decreased, otherwise, the opposite result is observed when adding KC1. In the presence of K＋ in reaction solution, K＋ could promote the growth of whisker along c axis and increases its aspect ratio.