Current issues relating to anti-solvent micronisation techniques and theirextension to industrial scales

Realisation of the potential of dense gas anti-solvent precipitation for co mmercially viable processing of fine chemicals is hindered by our inability to fully exploit the advantages afforded to dense gases. The feasibility o f producing dry uniformly sized micronised material using dense gas technol ogy has been well established on a bench scale. However, translating these advantages to an industrial scale remains a challenge for engineers. In thi s paper, issues specific to the process scale up of dense gas anti-solvent precipitation are discussed. Anti-solvent precipitation is essentially a mi xing process and any predictable increase in production rate is impossible without a thorough understanding of the dominant controlling factors. In th is paper the dominant process variables, issues such as safety, cleaning, r esidual solvent concerns, precipitate sizing and product handling are addre ssed. (C) 2001 Elsevier Science B.V. All rights reserved.