No description available.

No description available.

No description available.

No description available.

No description available.

No description available.

No description available.

"Tris-2-chlorethyl phosphate (TCEP) is a flame retardant and plasticizer that has been detected in drinking water sources and wastewater effluents in many countries. TCEP has been proven to be a recalcitrant compound that is also toxic and carcinogenic. The incomplete removal of TCEP in water and wastewater treatment plants necessitates that treatment processes be identified or developed that will completely remove TCEP from waters. Ozonation has been successfully used as an oxidant to degrade many problematic contaminants in water and wastewater. This research examined the effectiveness of ozone and ozone/hydrogen peroxide oxidation for removing TCEP from water. In laboratory experiments, batch reactions of TCEP solutions were conducted in purified water at different pH conditions and O3:H2O2:TCEP doses. The samples were tested at O3:TCEP molar ratios of 6:1, 15:1, and 30:1 and with O3:H2O2:TCEP molar ratios of 6:4.2:1, 15:10.5:1and to 30:21:1 respectively. Solution pHs of 4, 7, and 9 were investigated to cover the typical water and wastewater pH range. The Indigo Method was used to measure the starting ozone concentrations in sample water. TCEP concentrations were quantified by liquid-liquid extraction followed by gas chromatography (GC). Greater than 90% reduction of TCEP was achieved at equilibrium conditions with an O3:H2O2:TCEP molar ratio of 30:21:1 at all pH levels examined. Greater than 80% TCEP removal in diluted wastewater was observed at purified water to wastewater dilution of 4:1. The kinetics of oxidation of TCEP with ozone and ozone/hydrogen peroxide were explored in this research. It was found that the reaction rate constants of TCEP are lower than those of other contaminants typically found in water and wastewater. "

No description available.

Advanced electrochemical oxidation processes have emerged as a promising method for the destruction of persistent organic material in variable waste streams. Although the process has been successfully employed for wastewater treatment applications, high energy requirements, and the risk of formation of undesirable by-products may limit its application in the field of leachate treatment. This study focuses on the investigation of the feasibility of removing organics and ammonia by electrochemical oxidation coupled with ozone, Fenton or lime. Landfill leachate was treated by two different bench scale electrochemical oxidation reactors coupled with ozone oxidation, Fenton coagulation or lime precipitation. The electrochemical oxidation was conducted using a titanium anode coated with multi-metal oxides (MMO) at three-different current densities for different durations. Treatment performance was determined based on the removal of COD, ammonium-N, and turbidity. A three-level factorial design was established, and response surface methodology (RSM) was introduced to determine the optimum process parameters. The results suggest that the process can remove appreciable amounts of ammonium-N and COD in a very short time, demonstrating that the process is effective in rapidly degrading recalcitrant organics in leachate. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2019. / FAU Electronic Theses and Dissertations Collection