Feasible synthesis of anti-fouling amphiphobic composite membrane by surface modification with SiO2 nanoparticles for effective membrane distillation

Membrane distillation (MD) technology has shown unique advantages in treating saline organic wastewaters, however, improving membrane materials of anti-wetting/fouling properties is still agap for the large-scale application. In this study, a non-fluorinated composite membrane showing both good amphiphobic properties and high flux was synthesized by feasible electrostatic attraction. Characterizations indicated that SiO2nano- particles were successfully loaded on the PVDF membrane (SiO2/PVDF) surface to form a multi-level rough amphiphobic structure, with contact angles of water and ethylene glycol as 139 degrees and 128 degrees, respectively. In MD tests, the SiO2/PVDF membrane exhibited a stable flux of 15 LMH with 3.5 wt% NaCl and 19.5 LMH with 50 mg/ L kerosene. Notably, after a 24-hour continuous test, the flux remained above 9 LMH for NaCl and 11 LMH for kerosene, with salt rejection rates exceeding 98 %, indicating excellent anti-fouling characteristics. This study is expected to provide a feasible membrane modification for MD process in treating high saline organic wastewater.