The Role of Tempiating Agents in the Membrane Distillation Performance of Superhydrophobic PVDF Membranes

摘要

Membrane distillation has emerged in the past few years as an attractive alternative to current desalination systems, particularly where waste or low value heat is available. However, degradation of performance can arise due to progressive pore wetting in the membrane, compromising product quality and flux. Superhydrophobic modification of the membrane surface has been shown to reduce liquid penetration into the membrane pores. Recently, superhydrophobic (>150° contact angle) polyvinylidene fluoride (PVDF) membranes were successfully fabricated by combining low surface energy of fluorinated silanes with a nanostructured surface created by TiO2 nanoparticles. During this process, the tempiating agent was believed to play an active role in influencing the TiO2 nanostructure. The objective of this study is therefore to establish the relationship between tempiating agent properties, nano-architecture and wettability of the membrane modifications for membrane distillation applications.