Diesel particulate control

A method for reducing emissions of particulates from diesel engines, which comprises:

• operating a diesel engine with a fuel containing a fuel borne catalyst comprising a fuel soluble or dispersible cerium composition and a fuel soluble or dispersible platinum group metal composition;
• passing exhaust produced by combustion of the fuel and containing both cerium oxide and platinum group metal released from the fuel by combustion, through a diesel particulate filter having at least two stages comprised of
• (a) a catalyst section having a platinum group metal catalyst and/or base metal catalyst on contact surfaces within the catalyst section and
• (b) a filter section comprised of passages effective to remove particulates from a moving stream of combustion gases generated by combusting the fuel in the engine and holding them therein to permit their oxidation,
• wherein the improvement comprises utilizing levels of platinum group metal composition, cerium compositions, fuels and/or optional chemical enhancers to generate NO2 in the catalyst section in amounts sufficient to form cerium nitrates in the filter section whereby the cerium oxide is associated with and maintains dispersion of the platinum in the filter section, and the cerium nitrates will be available at the surface and within the soot particles to provide enhanced soot oxidation at a lower balance point than could be achieved without the provision of the platinum group metal and cerium fuel additive in the multi stage filter.