醋酸钠介稳区的测定

Determination of metastable region for sodium acetate

溶液的介稳区是结晶的基础研究之一。利用静态法测定醋酸钠在水中不同温度下的溶解度,同时利用激光散射法测定醋酸钠在不同温度、搅拌速率、降温速率条件下的超溶解度,得到溶解度与超溶解度的曲线从而拟合出醋酸钠在水中溶解度和超溶解度的方程,确定介稳区范围。研究结果表明,醋酸钠的溶解度随着温度的升高而升高。在一定条件下,搅拌速率越大、温度越高、降温速率越快,介稳区宽度越窄。

Metastable region of solution is one of the basic researches of crystallization. The solubility of sodium acetate at different temperatures in water was determined by static method. The supersolubility of sodium acetate saturated solution at different temperatures, stir rate, and cooling rate was determined by laser scattering method. The curve of solubility and supersolubility was obtained and the empirical formula of solubility and supersolubility for sodium acetate in water was fitted, thus determining the metastable region. The results show that the solubility of sodium acetate increases with the increase of temperature. The larger the stir rate, the higher the temperature and the larger the cooling rate, the narrower the metastable region under certain condition.