More stories related to SAE DETROIT – Specialty Chemical manufacturer Rhodia SA already has its diesel particulate filtration system installed on 1 million vehicles in Europe, but it says it will introduce a virtually maintenance-free version next year in an effort to enhance its acceptance locally and for potential future use in North America. (See related story: Rhodia Improves Eolys System, Hopes to Spur U.S. Market)

The current system uses a fuel-borne liquid catalyst that helps burn off particulate matter in diesel exhaust that is captured in a special filter. Particulate matter is the subject of growing health and environmental concerns and is beginning to be tightly regulated in environmental legislation in Europe and the U.S.

Rhodia's proprietary liquid catalyst, named Eolys, is injected into a vehicle's diesel fuel in minute amounts (currently about 10 parts per million) and is stored in a small container underneath the regular fuel tank. The current system is designed to last 75,000 miles (120,000 km) and requires a fairly expensive service visit (the equivalent of several hundred dollars) to the dealership to clean the particulate filter and replenish the Eolys mixture.

Rhodia particulate control system is already on 1 million cars in Europe.

The next-generation system, slated to be introduced in 2006, will be able to go 155,000 miles (240,000 km) before service is necessary, says Chris York, general manager - North America Rhodia Fine Inorganics and Silicones at an offsite presentation during the SAE World Congress here.

Given the longer service life of vehicles, particularly those with diesel powerplants, it would be wrong to characterize the new system as lasting “the life of the vehicle” but most original owners won't have to worry about maintaining the system, York says.

Rhodia is accomplishing this feat by using a more concentrated, reactive version of the liquid catalyst that takes up less volume, and by optimizing the system so that it requires smaller injection dose volumes of only 7 ppm.

Working with another company, Inergy Automotive Systems, Rhodia also has developed a new storage system for the catalyst that saves space and is easy to refill: The container - along with the system's special injector pump - is integrated into the fuel tank's plastic filler neck, as is a special fitting that allows easy refilling.

Rhodia officials also showed off a heavy-duty version of the particulate filtering system, aimed mostly at diesel engines used for urban buses. The company says it already has equipped commercial bus fleets for two cities in France with the system.