In this talk, I will present new results––both experimental and theoretical––on a new class of fully thermoset reverse osmosis (RO) membrane materials designed to operate at extreme temperatures and pressures. Conventional RO membranes comprise an ultra-thin, microporous cross-linked (thermoset) polyamide (PA) film formed over a mesoporous polysulfone (PSU) (thermoplastic) support membrane, which is cast over a macroporous nonwoven polyester fabric. The thermoplastic PSU supports experience permanent deformation and damage via plastic creep when exposed to high applied pressure (>50 bar) and/or feed solution temperature (>30 ºC). In contrast, the thermoset PA film minimally compacts under pressure, and recovers its original free volume when the applied pressure is relieved. Subsequently, we have developed a fully-thermoset composite RO membrane that resists compaction. We have employed advanced modeling methods along with traditional characterization and testing plus we developed a novel in operando technique – all for visualizing and quantifying the effects of compaction on both conventional and fully thermoset RO membranes. These new high-pressure/-temperature tolerant RO membranes can serve applications that have long been exclusively in the domain of thermal technologies. Once scaled, RO membrane-based solutions could be half the capital cost and half the energy demand of traditional thermal-distillation processes.
