| Abstract
| - The aerobic biodegradation and catalytic oxidation of vapor-phase 2-propanol (IPA) wereinvestigated. The catalytic oxidation of IPA was carried out over zinc, copper, and chromiumoxide catalysts prepared via a sol−gel technique in a fixed-bed reactor operated at atmosphericpressure and in the temperature range of 25−165 °C. The activity of the catalysts was measuredby means of the light-off temperature (defined as 50% conversion of IPA). The light-offtemperatures of zinc oxide, copper oxide, and chromium oxide are 90, 100, and 110 °C,respectively. The results indicate that, at relatively low temperature (40−100 °C), IPA waspartially oxidized, which resulted in acetone formation. The maximum acetone selectivity variedbetween 30 and 97% at ca. 100 °C, depending on the types of catalyst. For the biodegradationstudy, enriched solvent-tolerant bacterial cells were immobilized onto porous glass cylinderswithin a biofilter. Successful biofiltration of high solvent vapor concentrations of up to 34 g m-3was achieved. An average IPA elimination capacity of up to 280 g m-3 h-1 was demonstrated bythis biofiltration system. A slip feed experiment, using acetone, was investigated in order toassess the substrate specificity performance. The results show that the biofilter can deal withan alteration in feed composition and display no major reduction in the elimination performance.This paper shows that the concentration and compound distribution from the exit of a catalyticpartial oxidation process are consistent with the inlet conditions of a gas-phase biofilter containinga solvent-tolerant microbial consortium. This points the way toward a potential integrated biofiltration−catalytic combustion system for the overall enhanced pollution abatement performance.
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