Research Projects

Membrane distillation (MD) is a promising solution for water reclamation and zero liquid discharge (ZLD), particularly in industrial wastewaters and hypersaline brines. However, commercialization of MD has not yet been achieved due to the lack of a cost-efficient and high-performing membrane. Electrospun nanofibrous membranes (ENMs) have been introduced as a potential solution, but their surface roughness improvement is not enough for achieving sufficient anti-wetting and anti-fouling properties. The development of specific surface nanostructures with omniphobicity, particularly "re-entrant" micropillar structures or "double re-entrant" mushroom-like structures, is also required. Studies in material science and chemistry have shown that hierarchical nanograss and nanoflower structures can be grown on a copper-based substrate. However, no MD studies have attempted to grow double re-entrant nanostructures on nanofibers. The advantages of growing these nanostructures include less probability of detachment from the membrane and no need for fluorination, which poses potential environmental and health risks. A simple method combining electrospinning and in-situ growth for fabricating an omniphobic nanofibrous membrane with a bio-inspired nanoflower-on-nanoneedle double re-entrant structure will provide a new approach to designing hierarchical nanostructures on porous ENM surfaces. A systemic, long-term MD study using an in-house developed wetting detection system will illuminate how these nanostructures relate to MD performance. Adopting MD-Absorbent technology will achieve nearly zero liquid discharge (ZLD) and expand the versatility of MD membranes.