Design of superhydrophobic nanofiber membrane with robust pore structure for membrane distillation
Membrane distillation(MD)technology shows excellent advantages and potential in seawater desalination and high saline wastewater treatment,and electrospun nanofiber membranes have attracted extensive attention from researchers due to their high water flux and low mass transfer resistance.However,its loose and porous pore structure is susceptible to deformation of membrane pores caused by the shear force of water flow,which leads to wetting of membrane pores.In this study,we prepared superhydrophobic nanofiber membranes with a robust pore structure by impregnating and coating polyvinylidene fluoride(PVDF)nanofiber membranes with a mixture of polydimethylsiloxane(PDMS)and TiO2 nanoparticles(TiNPs)after hot pressing.The membrane has a contact angle of up to 160.3° and excellent membrane distillation performance,as well as high water flux of 39.3 kg/(m2·h)and durability up to 102 h in MD with a retention rate of more than 99.99%,which provides some guidance for the design of MD membranes in the future.