【摘要】 反应结晶是抗生素生产中常用的一种结晶方法 ,但目前国内反应结晶技术水平落后 ,普遍存在产品粒度分布过宽问题。加晶种的控制结晶是一种改善结晶产品粒度分布的有效方法 ,已广泛用于蒸发结晶、冷却结晶、溶析结晶等结晶体系 ,而未见报道在反应结晶过程中应用。本文对在头孢拉定反应结晶过程中投加晶种改善产品粒度分布进行了研究 ,比较了在相同的育晶条件下 ,超声波法制备的晶种、筛分后的成品作为晶种和自然起晶方式对最终产品粒度分布的影响 ,结果表明 ,加入超声波法制备的晶种得到的最终产品中间粒度最大 ,变异系数 (CV值 )最小。更多还原

【Abstract】 Wide crystal size distribution is a long existing problem in reactive crystallization process. By using careful seeding procedure, the crystal size distribution can be improved and has been successfully used in different crystallization processes such as, evaporative ; cooling ; and solvent out crystallization, yet only few reports of seeding being applied in reactive crystallization process. This paper reported the results of improving the crystal size distribution of cephradine by using an ultrasonic seeding process and results were compared with other processes such as, seed prepared by sieving and by spontaneous nucleation, under the same conditions. Results showed that the medium size of crystal products seeded by ultrasonic reactive crystallization process is the biggest one and the coefficient of variation (CV) is the smallest.更多还原