In-Situ Electrospun TEOS-Modified Superhydrophobic PVDF-HFP Membrane (UPM4) for Enhanced Direct Contact Membrane Distillation

Abstract

Due to the progress of society and the growth of the population, the crisis related to the availability of freshwater resources has become increasingly prominent. In order to address this issue, membrane distillation (MD) has emerged as a widely employed technique for the recovery and utilization of fresh water. Nonetheless, the application of MD has been hindered by challenges such as membrane wetting and membrane fouling. To overcome these obstacles, this study presents a novel approach for the in situ creation of a UPM4 superhydrophobic poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) membrane containing TEOS through an electrospinning process, specifically designed for direct contact membrane distillation (DCMD). The influence of thickness, porosity, and liquid entry pressure (LEP) was thoroughly investigated. The hydrophobicity of the membrane was evaluated through contact angle measurements, which were conducted using optical contact angle goniometry. The composition of functional groups was analyzed using Fourier-transform infrared spectroscopy (FTIR). The morphology of the membrane was examined using scanning electron microscopy (SEM). Ultimately, all of the electrospun membranes exhibited a sufficient level of hydrophobicity to be effectively employed in DCMD.