对羟基苯甘氨酸硫酸盐在水-丙酮中溶解度的测定与关联

利用灵敏的激光监视装置,采用恒温溶解法测定了对羟基苯甘氨酸硫酸盐在水-丙酮二元混合溶剂中的溶解度.实验温度范围约为303～323 K,水-丙酮混合溶剂中水的变化范围为0%～100%.在纯丙酮和低含水量的混合溶剂中,对羟基苯甘氨酸硫酸盐溶解度很低.混合溶剂含水9.09%以下时,溶解度随水含量增加略有降低.随着溶剂中水量的进一步增加,溶解度随之增大.在研究的温度范围内,溶质在纯水中的溶解度约为纯丙酮中的50～70倍.同一溶剂中,溶解度随温度升高而增大.用从Clausius-Clapeyron方程推导的理论模型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,平均相对误差1.73%.实验结果可应用于对羟基苯甘氨酸的提纯和优先结晶法拆分工艺.

Measurement and Correlation of Solubility of dl-p-Hydroxyphenylglycine Sulfate in Acetone-Water Solvents

By the help of the sensitive laser monitoring observation technique, the solubility of dl-p- hydroxyphenylglycine sulfate (dl-p-HPGS) in binary acetone-water solvent mixtures was measured by isothermal method in the temperature range between 303 K and 323 K. In the study, the water content in binary solvents used was 0%~100%. It is found that the solubility of dl-p-HPGS is very small in pure acetone and in the solvent with low water content. When the water content is less than 9.09%, the solubility decreases slightly with the increase of the water content, and then it will increase with the increase of the ratio of the water content further. Among the temperature range investigated, the dl-p-HPGS solubility measured in pure water is about 50 to 70 times larger than that in pure acetone. The solubility model derived from Clausius-Clapeyron equation was used to correlate the temperature and the solubility of dl-p-HPGS. The solubility calculated by the model is in good agreement with the experimental results, and the overall average relative error is 1.73%. The solubility measured in this study can be used for the dl-p-hydroxyphenylglycine purification or its optical resolution by preferential crystallization procedure.