Development of Ethenylene-Bridged Organosilica Membranes for Desalination Applications

A promising new ethenylene-bridged organosilica membrane has been developed for pervaporative desalination of water. Due to the introduction of polarizable and rigid ethenylene bridges in the silica networks, the membrane exhibited an improved water affinity and superior hydrothermal stability. The ethenylene-bridged organosilica membrane delivered a high water flux of up to 14.2 kg m(-2) h(-1) with a high NaCl rejection of 99.6% for pervaporative desalination 70 degrees C. Moreover, the membrane was highly applicable and stable for desalination of saline water under a wide range of salt concentrations. The rapid permeation of water molecules through the membrane was attributed to the open pore structure and the water pore wall interactions, while the transport of hydrated salt ions was explained by the relatively broad pore size distribution of the ethenylene-bridged silica networks.