Abstract
Oxy-combustion systems result in enriched CO
in exhaust gases; however, the utilization of the concentrated CO
stream from oxy-combustion is limited by remnant O
. CH
oxidation using Pd catalysts has been found to have high O
-removal efficiency. Here, the effect of excess CO
in the feed stream on O
removal with CH
oxidation is investigated by combining experimental and theoretical approaches. Experimental results reveal complete CH
oxidation without any side-products, and a monotonic increase in the rate of CO
generation with an increase in CO
concentration in the feed stream. Density-functional theory calculations show that high surface coverage of CO
on Pd leads to a reduction in the activation energy for the initial dissociation of CH
into CH
and H, and also the subsequent oxidation reactions. A CO
-rich environment in oxy-combustion systems is therefore beneficial for the reduction of oxygen in exhaust gases.
