Symposium SM13: Advances in Membrane and Water Treatment Materials for Sustainable Environmental Remediation
Niraj Ashutosh Vidwans, Texas A&M University
Strategies for the Scale-up of the Photocatalysis Process for Disinfecting Large Quantities of Water
Written by Arun Kumar
Current water disinfection methods are limited by the release of harmful by-products, waste produce, and incomplete pathogen deactivation. In this regard, the photocatalytic disinfection method using titanium oxide (TiO2) can be a better alternative for the process says Niraj Vidwans from Texas A&M University. TiO2 can efficiently generate reactive oxygen species when exposed to ultraviolet-A light that can in turn showcase excellent antimicrobial activity and contaminant removal from the water. TiO2 aeroxide P25 nanoparticles are a standard catalyst for the photocatalytic process, but they are often hard to remove from the water after disinfection. So the research group prefers the use of porous TiO2 nanowires for the photocatalysis process. Initial experimentation shows that ultraviolet light-A combined with the nanowires were able to disinfect E. coli bacteria by four orders exhibiting good catalytic activity. Several flow pattern changes and chemical composition changes in the TiO2 nanowires make them compatible for disinfection applications in different water sources. Following the optimization strategies, a bench-scale up setup was used to measure the efficiency of their process in a flow photocatalytic bioreactor. The team also demonstrates that the photocatalyst can be recovered and reused for photoreaction. Vidwans envisions developing a protocol to expand the flow reactor into a continuous-mode flow reactor for photocatalytic disinfection. The high specific surface area obtained when TiO2 is made in nanocrystalline form (nanoparticles and nanowires) aids in engineering efficient water remediation processes.