Water Resources Research Act Program

Details for Project ID 2014PR164B

Feasibility of sintered recycled glass functionalized with micro- and nanosized TiO2 particles for the degradation of trihalomethane precursors from surface waters

Institute: Puerto Rico
Year Established: 2014 Start Date: 2014-03-01 End Date: 2015-02-28
Total Federal Funds: $17,304 Total Non-Federal Funds: $34,069

Principal Investigators: Pedro Tarafa, OMarcelo Suarez

Abstract: Trihalomethanes (THM’s) are a group of organic chemicals, often present in drinking water and formed when chlorine, a chemical disinfectant, reacts with natural organic matter (NOM) in raw water. THM’s are environmental pollutants and are of concern because they are potential carcinogens. The THM’s formation is dependent on several variables: the concentration and nature of the NOM in the raw water, chlorine contact time, the residual chlorine concentration in the water and the pH and temperature of the water. Many water treatment plants in Puerto Rico are facing non-compliance problems with the standard levels of THM’s in drinking waters (Joel Lugo, PRASA Executive Director-West Region, personal communication). Among the THM’s control strategies are changes in chlorination practices such as lowering chlorine dose or changing the point of application. However, the residual chlorine concentration for preventing water re-contamination, may promote THM’s formation within the distribution network. Another strategy is to remove THM precursors (i.e. NOM) before chlorine is added to the water. This approach seems to be more attractive because by lowering NOM, the overall disinfectant demand is also reduced, thereby reducing the possibility of the formation of more THM’s. Consequently, our long term goal is to develop and implement a low cost pre-oxidation alternative made of sintered recycled glass functionalized with anhydrous titanium (IV) oxide powder (TiO2) for the degradation of NOM in raw waters for the control of THM’s. TiO2 will serve as catalyst in which a photo-catalytic reaction will undergo to oxidize the organic matter. To accomplish such goal, the present research proposal is divided in three main parts: (1) structural evaluation of the glass/TiO2 composite in order to determine porosity and percolation rates; (2) mechanical analysis to determine compression characteristics of the composite; and (3) to evaluate the efficacy of the composite in degrading NOM under the influence of UV light for the photo-catalytic reaction. The conception and realization of this project will yield in essential data and information to set the foundations for a novel process in the degradation of THM’s precursors, and, as a consequence, minimize THM’s formation in drinking water.