Induction Time of L-Isoleucine Crystallization with the Presence of Electric Field

Nucleation signifies the start of phase transition where nuclei of crystalline forms in the solution prior to crystal growth. There is an increasing demand in investigating reliable method to measure the nucleation rate in order to control the process an it has been reported that electric field has been successfully used to control the nucleation consequently the crystallization process. Hence, it becomes the objective of this paper to examine the effect of electric field on the induction time crystallization of L-isoleucine. The experiment was conducted in a 200 mL jacketed reactor where constant stirring was provided by retreat curve impeller and the temperature was regulated using two refrigerated baths. The induction time in this work was found to be lower than system without the application of electric field due to the hydrophobicity of L-isoleucine molecule and competition to form hydrogen bond with water when electrolysis occurs. The interfacial tension calculated shows no significant change with concentration while nucleation rate increases as the supersaturation increases. The critical radius calculated also proves to be smaller and decreases when supersaturation increases. The result also suggests the presence of new crystalline phase for the crystals produced at 48 g/L and supersaturation ratio of 1.08 and 1.14.