Tannic acid crosslinked chitosan membranes for pervaporation desalination

Pervaporation (PV) membranes for desalination show significant potential, attracting increasing attention. Herein, polyphenol (tannic acid) was used to crosslink chitosan to prepare composite membranes for pervaporation desalination. The effects of the coating method, the concentrations of chitosan (CS) and tannic acid (TA), the deposition time of CS and TA, and the thermal annealing time on the desalination performance of the pervaporation membranes were investigated to explore the relationship between membrane structure and pervaporation desalination performance. After optimizing the synthesis conditions, a high flux pervaporation desalination membrane (44 kg·m −2 ·h −1 at 50°C and 92 kg·m −2 ·h -1 at 70°C) with a NaCl rejection higher than 99.9 % was prepared by co-depositing chitosan and TA on a polysulfone support. This work demonstrates TA crosslinked CS composite membranes have promising research prospects and potential applications in pervaporation desalination.