Dr. Paul Simone from the University of Memphis will present “Moving towards on-line, real-time monitoring of haloacetic acids at concentrations relevant to drinking water utilities” to the department.
The chlorination of drinking water in the United States has been a major public health success story. However, the natural organic matter present in the source waters reacts with chlorine to produce disinfection by-products (DBPs). The two most prominent classes of DBPs are trihalomethanes (THMs) and haloacetic acids (HAAs). Both THMs and HAAs are regulated by the USEPA in drinking water because they are carcinogenic. The THMs are non-polar and volatile and readily analyzed using gas chromatography-based methods and analyzers. The HAAs are polar and anionic at the pH of drinking water making them significantly more difficult to analyze using gas automated techniques.
The path to development and commercialization of a fully-automated HAAs analyzer will be presented. The first reported post-column reaction chemistry developed for HAAs analysis used anion exchange chromatography to first separate the HAAs in time, followed by reaction with nicotinamide and base to form a fluorescent product (365 ex., 455 em.). The analyzer had method detection limits for each HAA species of 1 – 10 μg/L, with subsequent research adding internal standardization. However, improved method detection limits were needed to determine HAAs concentrations in the range of 1 – 5 μg/L at the point of entry in the drinking water treatment plant. To achieve this, a fully-automated preconcentration procedure with on-line internal standardization using sequential injection analysis (SIA) was developed. The SIA procedure is integrated as a module with post-column reaction ion chromatography (PCR-IC) for on-line, real-time analysis of HAAs in drinking water distribution systems at concentrations. The method detection limits for the individual HAAs species were all less than 0.9 µg/L, which is comparable to the standard USEPA method for HAAs. Side-by-side comparison studies to the standard USEPA method will be discussed.
Dr. Paul Simone is an assistant professor of chemistry at The University of Memphis, where he earned both his B.S. Ch. and Ph.D. He started his career as an tenure-track professor at The Citadel in Charleston, SC. Simone works at the nexus of research and business, developing new technologies at The University of Memphis to help drinking water utilities comply with ever stricter USEPA regulations of drinking water disinfection by-products. The new technologies are protected through patents and subsequently commercialized through Foundation Instruments, Inc. Foundation Instruments was co-founded with Gary L. Emmert and Wei Wu-Emmert, and is a high-tech, small business spun out from The University of Memphis.