Induction of crystal nucleation by the unidirectional movement of the heterogeneous interface in a supersaturated solution

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K04816
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 27010:Transport phenomena and unit operations-related
• Research Institution: Osaka City University
• Principal Investigator: Igarashi Koichi 大阪市立大学, 大学院工学研究科, 准教授 (70315977)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 結晶核発生 / 不均一界面 / 結晶多形

Outline of Final Research Achievements

The movement of plastic pieces on the nucleation of L-alanine crystals. The plastic pieces such as polypropylene were inserted into the supersaturated solution of L-alanine, and the probability of nucleation was evaluated. When the moving speed of the plastic pieces was set to 0.5, 2.0, 5.0 mm/s, the maximum nucleation induction effect was obtained at 2.0 mm/s.
Next, we attempted to induce nucleation using polypropylenes with different polymorphisms (α-PP, β-PP). The α-PP induced the nucleation of L-alanine, but β-PP had only a small inducing effect. Finally, the polypropylene with different α / β ratios was applied to the solution, there was a clear correlation between the β crystal ratio and the probability of nucleation.

Free Research Field

晶析工学

Academic Significance and Societal Importance of the Research Achievements

晶析操作は、医薬品、食品、化学製品の生産に広く用いられている分離精製操作のひとつであるが、粒径や粒径分布、結晶多形、形状、純度などの様々な結晶特性を制御する必要があり、「目的の機能を有する材料を創製する操作」としての役割も重要である。特に核発生過程は重要で、核発生の頻度やタイミングが粒径や分布に直接的な影響を及ぼす。結晶核発生メカニズムを解明することは学術的および社会的に有益である。