Development of New Method for Producing Nanocrystals Using Nanomist as a Crystallization Field

Abstract

A new crystallization process for producing nano-order ultrafine crystals was developed by combining anti-solvent crystallization with electrospray which can generate nanomist acting as a crystallization field. Anti-solvent crystallization was performed in a batch crystallizer using glycine as a crystallized material and alcohol as an anti-solvent. The effects of the operating conditions on the mean diameter of produced glycine crystals were investigated. The experimental results clearly demonstrated that the crystal diameter tended to decrease with increasing applied voltage and decreasing flow rate. A minimum mean crystal size of 192 nm was attained in a batch crystallizer. Next, a unique counter collision crystallizer was introduced and the effects of the operating conditions on the mean crystal diameter were investigated. As a result, the higher voltage and the lower flow rate produced smaller crystals similar to the batch crystallizer. The counter collision crystallizer could successfully produce crystals with a minimum mean diameter of 295 nm.