Masters Thesis Defense – Chemistry | Mr. Billy Johnson

Mr. Billy Johnson – Master of Science in Chemistry Candidate

Advisor: Dr. Jordan Poler

“Synthesis and characterization of novel anion-exchange resin-coated single-walled carbon nanotubes for use in water purification”

Abstract:

Natural organic matter (NOM) is active in all water sources, and poses a potential health hazard. Modern water treatment methods rely on the use of chlorine as a disinfectant to remove microbial pathogens. However, certain NOM will react with chlorine to form disinfectant byproducts (DBPs), which are known carcinogens. These types of compounds are very difficult to remove by current treatment processes, so new materials must be developed to alleviate this growing problem. We have synthesized our “NanoResin” in water by covalently attaching poly(vinylbenzyl trimethylammonium chloride) to Single-Walled Carbon Nanotubes (SWCNTs), which acts as an anion exchange resin, for removal of these contaminants. Polymer was grown via Atom Transfer Radical Polymerization (ATRP), and attached to the SWCNTs using the same catalyst under the same reaction conditions. Functionalized SWCNTs were then characterized using Raman Spectroscopy, IR, and SEM showing the polymer was irreversibly attached to the nanotube and SEM showed a conformal polymer coating. NOM can be extracted from water sources by adsorption to these polymer chains on the functionalized SWCNTs. These materials can be recycled and then reused through addition of NaCl. This is a sustainable solution to a very difficult environmental problem. Our materials have more than 106 times the surface area compared to commercial resins, making them a more effective adsorbent material. Langmuir adsorption studies show a significantly higher adsorbent saturation capability. These materials display markedly greater sorption kinetics, working essentially on “contact” whereas other resins take upwards of one hour to reach equilibrium.

Monday, May 2, 2016 @ 12:00pm
Room 116 Burson