Anti-fouling and anti-wetting membranes for membrane distillation

Membrane Distillation (MD) is a thermally driven membrane separation process and shows promising water recovery from diverse wastewater sources. While reverse osmosis (RO) continues to be the dominant desalination technology, opportunities exist for the development of alternate low-energy separation technologies, especially for high-salinity streams. The MD process has generated interest in the separations community as a potential alternative either as a standalone or hybrid technology with other separation technologies like RO. Development of advanced membrane materials beyond the state-of-the-art must be pursued in order to improve the energy efficiency of the process; therefore, the most notable efforts in creating improved MD membranes are reviewed in this paper. Specifically, developing anti-wetting and anti-fouling membranes are the primary areas of interest in terms of new material development. This paper reviews the recent development of MD membranes and highlights some of the challenges for practical implementation. Finally, we provide insights into some key knowledge gaps and recommend a rational approach to design MD membranes.