Development of polyimide membrane for solvent resistant filtration

In this study, we mainly investigated the membrane permeability and ability for applications in harsh solvent environments, an excellent stable polyimide membrane was successfully developed by Taiwan Textile Research Institute (TTRI). The novel technologies combined molecular design, cross-linked and membrane processing, and these membranes can be safely used in various polar organic solvents such as NMP, DMAc, IPA, alcohol, etc. Therefore, the objective in urgent need for development in the field is to prepare a separation membrane with good solvent resistance and make it processed that can be used in ultrafiltration (UF), pervaporation (PV) or assisted pre-esterification in a biodiesel process. In our research, we focus on the development of PV of dehydration process. In PV testing, the feed of isopropanol (IPA) solution or ethanol (EtOH) solution concentration can increase from 70 to 99 wt% or from 70 to 90 wt%, and the permeation concentration of water is all higher than 95%. Based on the above, it has the superiority of polyimides over other polymers in separation property as distinguished materials for pervaporation.