针对之前团队提出的微尺度下流动体系介稳区宽度的测定方法提出了两点改进,测定了微尺度下磷酸二氢钾流动体系的介稳区宽度,探讨了介稳区宽度对微通道结晶过程的指导作用。研究结果表明,经过对搜索方式和调整进料温度的改进后,可提高测量的效率和准确性。磷酸二氢钾的介稳区宽度随体系流速和温度的增加而减小。当流速为0.026 m/s时,40 ℃和50 ℃磷酸二氢钾饱和溶液的介稳区宽度分别为1.8 ℃和0.4 ℃,介稳区宽度显著变窄。这一发现,对微通道反萃-结晶技术的操作调节具有重要的指导意义。此外,研究发现微通道中制备的硫酸钡和普鲁士蓝颗粒的粒径更小,这是由于介稳区宽度变小利于晶体成核而导致。

Two improvements to the previous team′s method for measuring the metastable zone width of the flow system at the microscale were proposed.The metastable zone width of the potassium dihydrogen phosphate flow system at the microscale was measured,and the guiding effect of the metastable zone width on the microchannel crystallization process was discussed.The research results showed that the efficiency and accuracy of measurement could be improved by improvements of search method and adjustment of feed temperature.The metastable zone width of potassium dihydrogen phosphate decreases with the increase of flow rate and temperature.When the flow rate was 0.026 m/s,the metastable zone width of saturated potassium di-hydrogen phosphate solution of 40 ℃ and 50 ℃ were 1.8 ℃ and 0.4 ℃,and the metastable zone width became significantly narrower.This finding had important guiding significance for the operation and adjustment of microchannel back-extraction-crystallization technology.In addition,the study showed that BaSO₄ and Prussian blue particles prepared in the microchannel had smaller particle sizes,which was due to the narrower metastable zone width that facilitates the nucleation of crystals.