A diesel oxidation catalyst (DOC) catalytic converter for at least the conversion of carbon monoxide and hydrocarbons, removal of a fraction of particulate matter, and decrease of sulfur trioxide emissions within exhaust gases from an engine and consequently of sulfuric acid, is disclosed. The DOC may include any suitable configuration including at least a substrate and a washcoat, where the substrate has a plurality of channels, suitable porosity, offers a three-dimensional support for the washcoat, and is made of any suitable material. The washcoat may be deposited on the substrate by any suitable method, and may include a mixture of at least one or more carrier material oxides and one or more catalysts. Suitable materials for the carrier material oxides may include titanium dioxide, tin dioxide, and zirconium dioxide, among others, excluding aluminum oxide (Al2O3), which may serve for a decrease of sulfur trioxide emissions and consequently of sulfuric acid mist. Suitable catalysts within the washcoat may include platinum, palladium, rhodium, and iridium, among others.