The North American version of the new 2013 Honda Accord (see 2 October AEI) features a new exhaust catalyst design that reduces the use of rhodium by 50%. The automaker plans to adopt the catalyst technology across its vehicle lines.
The exhaust catalyst substrate used in the outgoing generation of Accord (2012 model) contains no platinum. The new system, codeveloped by Honda and a supplier, uses its palladium loading to accelerate the process of absorption and desorption of oxygen, which reduces the need for rhodium for purifying the emissions.
Two catalytic converters are employed on the Accord’s 2.4-L direct-injected I4 (shown). The upstream close-coupled converter mounts directly to the cylinder head via an integrated exhaust manifold. A second converter is positioned slightly downstream, beneath the passenger compartment floor. Both units use a thin-wall design that increases internal reaction area and improves efficiency.
With the global trend of tighter emissions regulations, the demand for precious metals used for automotive catalysts—primarily platinum, rhodium, and palladium—is expected to continue to increase.
Honda claims the adoption of this new catalyst will reduce the use of precious metals by 22% (including a 50% reduction in rhodium) compared to the current model Accord. Moreover, the new catalyst’s design and materials content results in 37% lower cost per unit, while complying with California’s stringent SULEV standards as well as U.S. Tier 2 Bin 5 regulations.
A PZEV (partial zero-emissions)-certified Accord also will be available in California, Connecticut, Maine, Maryland, Massachusetts, New Jersey, New York, Oregon, Pennsylvania, Rhode Island, Vermont, and Washington.