Anti-solvent crystallization of L-alanine and effects of process parameters and ultrasound

Abstract

L-alanine is an important amino acid that constitutes proteins and provides biological advantages to the human body. This study examined conditions for the crystallization of L-alanine using liquid anti-solvents and ultrasound as an auxiliary tool. Effects of process variables on the distribution of particle size and external habit were investigated. Propanol was found to be the most appropriate anti-solvent. In addition, results of particle size analyzer and scanning electron microscope revealed that the particle size of L-alanine crystals increased with an increase in L-alanine concentration, injection rate, or crystallization temperature. Ultrasound also caused significant particle size reduction.