Excimer Photo-Oxidation (EXPO) of Dilute Gaseous Effluents

A novel low-temperature technology for treatment of dilute gaseous effluents contaminated with volatile organic compounds (VOCs) and other hazardous air pollutants (HAPs) is needed. Existing and emerging technologies are based on various combinations of thermal, photothermal and catalytic processes in oxidative or reductive environments. They suffer from emission of toxic substances, employment of inadequate UV light sources, presence of catalysts and disposal/liability problems. These drawbacks render these processes complex and expensive. This Phase I proposal offers a novel low-temperature technology designated Excimer Photo-Oxidation (EXPO) for treatment of dilute gaseous effluents contaminated with chlorocarbons and chlorofluorocarbons. The most innovative aspect of the EXPO technology is the employment of a unique, recently developed very powerful Excimer UV lamp (not laser). Excimer lamps combine selective and intensive UV radiation, which until now, only Excimer lasers could provide, with the relative simplicity and affordability of conventional UV lamps. This intense UV emission selectively initiates dissociation of targeted molecules, enhancing chemcial reactivity and leading to effective oxidation at or near ambient temperature. The end products are inorganic acids (HR, HCl) and environmentally benign products CO2, H2O. The primary objective of Phase I is to experimentally and computationally demonstrate feasibility. To achieve this goal, a four-task work plan is proposed. It consists of (1) design and contruction of two (2) photochemical reactors: (static with Excimer laser, flow with Excimer lamp); (2) experimental investigation; (3) chemical modeling; and (4) cost analysis. Successful completion of Phase I will determine the optimal operating conditions for a pilot-scale prototype, and will provide a technical foundation for a comprehensive Phase II R&D leading to a field demonstration followed by commercialization in Phase III.