摘要
研究了灰黄霉素在超临界 CO2 中的溶解沉析过程 ,测定了其溶解度。结果表明在实验范围内灰黄霉素在超临界 CO2 中处于反常冷凝区 ;通过超临界流体沉析过程 ,可获粒度 <5μm的灰黄霉素颗粒 ;反常冷凝区与正常冷凝区内操作的沉析过程 ,具有相反的温度影响与相同的压力影响。
Solution and deposition of griseofulvin in supercritical CO_2 were researched and published. The solubility of griseofulvin in supercritical CO_2 was determined by flow method and correlated by PR EOS. The results show that the solubility of griseofulvin reduces with rising temperature under fixed pressure within the operation region. Thus, there must be some supersaturation in preexpansion section because the fluid should be heated to a higher temperature before it enters the nozzle to keep the fluid in singlephase area during the throttling. This effect is never discussed in literatures. Deposition of griseofulvin in supercritical CO_2 was also researched in an apparatus that was designed and set up by ourselves. Effects of nozzle L/D rate, and preexpansion temperature and pressure were investigated and the results show that fine griseofulvin particles of less than 5μm can be formed by that process. Smaller particles can be obtained at higher L/D rate, higher preexpansion temperature and under lower pressure. This is the result of the solubility of griseofulvin in supercritical CO_2 in the converse condensation region. Thus, higher temperature will cause high supersaturation rate and enlarge the nucleation rate. It means the particle size will be reduced. The experiment results show that the temperature effect of RESS in the converse condensation region is converse to those in the normal region and the pressure effects under two conditions are similar.
出处
《华东理工大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2000年第3期225-227,共3页
Journal of East China University of Science and Technology
