【摘要】 分别采用恒温溶解法和变温溶解法测定了对羟基苯甘氨酸在水-丙酮-硫酸混合溶剂中的溶解度曲线和超溶解度曲线,利用激光监视装置检测测定系统中晶体的消失和产生,实验温度范围约为303~323K。随着混合溶剂中水的增加,溶解度略有增加;酸度增加,溶解度有较大幅度的增加。用经验方程二次多项式关联溶解度与温度的关系,计算的溶解度和实验值符合良好。测得的超溶解度曲线与溶解度曲线基本平行,介稳区宽度以最大过冷度表示约为1.5~2.4K,温度升高时介稳区宽度略有减少。溶剂中水含量或硫酸含量增加将使介稳区宽度变小;降低搅拌速度使介稳区明显变宽。实验结果可应用于优先结晶法拆分对羟基苯甘氨酸。更多还原

【Abstract】 Using isothermal method and the ploythermal method the solubility curve and supersolubility curve of dl-p-hydroxyphenylglycine in water-acetone-sulfuric acid mixed solvents were measured respectively at 303K to 325K. The disapperance and apperance point of crystal in the measured system was detected by a laser monitoring observation technique. It is found that the solubility increases slightly with water concentration and increases significantly with sulfuric acid concentration in mixed solvents. The measured solubility curve and supersolubility curve are almost parallel. The metastable zone width represented by maximum undercooling is about 1.2K to 2.4K, and it will slightly decrease with increasing saturation temperature. Increasing sulfuric acid concentration or water concentration in solvents reduces metastable zone width. Decreasing stirring rate can enhance the zone width significantly. The experimental results can be applied to the optical resolution of dl-p-hydroxyphenylglycine by preferential crystallization procedure.更多还原