Vapor-Phase Catalytic Oxidation of Mixed Volatile Organic Compounds.

摘要

An initial 3 year study was undertaken to develop efficient low-temperature catalysts for selective oxidation of chlorinated VOCs (chiefly methylene chloride and trichloroethylene) to benign products. An organized screening process for choosing and evaluation catalyst candidates (catalyst development methodology) was formulated. Principal catalyst selection criteria were: activity, selectivity, and stability. Thermodynamic limitations on chlorinated VOC destruction were checked at reaction temperatures and found to favor products consisting of CO2, HCl, Cl2, and H2O, with negligible chlorinated hydrocarbons remaining. Nine catalyst systems, containing one or more supported transition metal oxides (three primary, six secondary), were formulated and tested using this methodology with a monolithic reactor system. Analytical techniques for reactant and product stream determinations (largely carried out by gas chromatography mass spectrometry methods) showed improvement during the study with reactor mole balances on chlorine and carbon.