Date of Award
Master of Science in Chemical Engineering - (M.S.)
Chemical Engineering, Chemistry and Environmental Science
Joseph W. Bozzelli
A laboratory study has been performed on the wastewater treatment (destruction of organic species in water) using a novel process called Integrated Adsorption-Oxidation (IAO) where activated carbon is being utilized as a catalyst-adsorbent, and ozone as oxidant. The results of ozonation alone on the pollutants in water are also reported to provide a comparison with the adsorption-oxidation scheme in semi-batch reactions. All experiments were conducted at room temperature in a semi-batch reactor using five (water soluble) representative chemicals as pollutants: Aniline, Acetamide, Pyridine, N,N-dimethyl formamide and O-cresol. We also studied two volatile compounds: Trichloroethylene and Chloroform. Phenol was studied in a continuous flow reactor.
Results indicate that this new integrated adsorption-oxidation technique provides substantially improved performance over either ozonation or adsorption operating as separate treatment processes. The presence of carbon appears to serve a catalytic effect, where the ozone and active radical species produced in the reaction process now act to regenerate charcoal during the process. This changes a separation technology to a destruction technology.
A detailed analysis of the reaction process supplies important information for understanding the reaction mechanism, and in developing a kinetic model for the future.
Improvements in destruction rate constants for this combined adsorption/oxidation process compared to rate constants for reaction with ozone alone are: Compound Ratio Aniline 1.21 Pyridine 1.13 N,N-dimethyl Formamide 1.59 O-cresol 1.17 Acetamide 1.68 Trichloroethylene 1.14 Chloroform 1.11
Ratio = kIAO / kozone alone
Ho, Kin, "Charcoal catalyzed ozone decomposition of organic pollutants in water" (1991). Theses. 1849.