(245b) Molecular Separation in Organic Solvents

Organic Solvent Nanofiltration (OSN) separates molecules present in solutions of organic solvents. In OSN, a pressure gradient is applied across a solvent stable nanoporous film, inducing transport of liquid across the film. Depending on relative permeation rates, molecular species in a feed liquid stream can be concentrated and separated. Typically OSN will use a small fraction of the energy of thermal methods such as evaporation and distillation, and can work at temperatures around ambient. Two challenges for application of OSN technology in the chemicals and pharmaceutical industry have been: (i) the lack of membranes with wide solvent resistance, and which retain their nanostructure with exposure to aggressive liquids such as dipolar aprotic solvents (DMF, DMSO, THF); and (ii) the need for membranes to have minimum extractable components, and so be utilisable in cGMP environments.

This presentation will describe the recent development of a new generation of superstable OSN membranes and modules, and applications to processes typically used in chemical manufacturing routes. The DuraMemTM series OSN membranes are made through post-formation processing including crosslinking of polymer membranes, which makes them stable in polar solvents such as acetone, DMF and THF. The membranes are available for lab testing as flat sheets, and as spiral wound cartridges for scale up. The cartridges are being successfully applied in cGMP manufacturing processes.

Applications of OSN membranes to concentrations, purification, recycling of organometallic catalysts, solvent exchanges, and metal (Pd) removal from post-reaction mixtures will be described. Purifications can comprise removing smaller reagents from larger products to avoid undesirable subsequent reactions, or removal of larger oligomeric or colour bodies from post reaction mixtures. The scale up of the manufacture of the DuraMemTM series will be described, together with the type of equipment used to progress from lab bench to kilo and process scale.