SURFACE MODIFICATION OF REVERSE OSMOSIS MEMBRANES (RO) TO ELIMINATE FOULING, CONCENTRATION POLARIZATION, AND REDUCE ATRAZINE IN WATER
Sharma, Siddharth A
Area of Honors:
Bachelor of Science
Harry R Allcock, Thesis Supervisor Ali Borhan, Honors Advisor
Reverse Osmosis Membranes Separations Water Purification Desalination
Reverse Osmosis membranes are an excellent method for desalination, wastewater reuse, and industrial water recovery, but have major flaws that still need to be addressed for them to be able to help solve the world water shortage crisis. Their high-energy usage during operation is caused due to fouling and concentration polarization (cp) that become more and more problematic over operating time. Earlier, the Kumar lab demonstrated that a easily scalable copper oxide (CuO) nanoparticle coated membrane, could mitigate concentration polarization and fouling via an chemical reaction that indces micromixing at the membrane surface (without stopping the process). These membranes catalyzed the degradation of hydrogen peroxide pulse-injected into the feed solution at low concentrations (2-7 mM). The reaction generated convection also managed to enhance solute back diffusion mass transfer coefficients, resulting in the near elimination of concentration polarization. Next, we decided to use catalase instead of CuO nanoparticles to accomplish similar results. Catalase being an enzyme could be a more ecofriendly and potentially more efficient alternative over metal oxide nanoparticles to accomplish the same results. Preliminary testing seem to show that while catalase is does not release as many free radicals, its reaction with hydrogen peroxide is more rigorous. We have also been able to show that catalase coated membranes are able to reduce fouling in oily water separations when exposed to hydrogen peroxide.