Effect of an economical oxidation catalyst formulation on regulated and unregulated pollutants from natural gas fueled heavy duty transit buses

Document Type

Journal Article

Publication Date


Subject Area

mode - bus, place - north america, policy - environment, technology - alternative fuels


Natural gas transit bus; Unregulated emissions; Oxidation catalyst; Regulated emissions


The paper discusses the performance of heavy-duty natural gas transit buses retrofitted with economic oxidation formulation oxidation catalysts in reducing regulated and unregulated emissions. The regulated emissions exhibited a 99% reduction in emissions of carbon monoxide, a 62% reduction in emissions of hydrocarbons with the presence of the oxidation catalyst, and a 96% decrease in carbonyl compound emissions. The catalyst formulation effectively targeted the lower chain volatile hydrocarbon fraction in the exhaust, which generally requires high light-off temperatures. Overall, the catalyst produced a 93% reduction in emissions of volatile organic compounds and was effective in reducing PAH emissions by 46%.


Permission to publish the abstract has been given by Elsevier, copyright remains with them.


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