Towards production of second generation P84 OSN membranes and modules for pharmaceutical applications

Abstract

This thesis describes the developments that led to the first polymeric OSN membrane and modules for applications in harsh solvent environments (e.g. DMF and THF), commonly used in the pharmaceutical industries. The chemical crosslinking of integrally skinned asymmetric P84 membranes has been shown to significantly enhance the chemical stability of the membrane thus allowing stable performance in these solvents that solubilise P84. The main issues relating to the production of the membrane and membrane modules addressed in this thesis are: (i) The impact of drying on membrane performance It was concluded that air-drying of water- and solvent-wetted membranes is not desirable for maintaining functional performance and that they must be impregnated with a preserving agent to maintain their properties (chapter 3). (ii) Development of highly solvent resistant adhesive systems for spiral wound module It was found that the key parameters influencing solvent stability are the available free volume in the epoxy adhesive and the functional groups present in the final adhesive network (chapter 4). (iii) Optimising the adhesive curing conditions for P84 OSN membrane modules A compromise need to be made in the curing conditions to achieve a highly solvent resistant adhesive whilst maintaining the membrane's performance, and a novel curing technique is also invented (chapter 5). Finally, chapter 6 describes how these solvent resistant P84 modules prepared using the knowledge gained from previous chapters can be applied to classic purification processes in the pharmaceutical industries. Overall, this thesis demonstrates a significant step forward in the knowledge and understanding of the formation and use of P84 based OSN membrane and membrane modules. This will open up more opportunities for applying this emerging separation technology in the pharmaceutical industry.