- Category: Technology
29 Apr 2013
- Published on Monday, 29 April 2013 09:13
- Hits (1551)
A new catalytic substrate made of ceramic foam allows for cheap and efficient clean-up of exhaust gases from diesel vehicles.
Empa has developed the catalytic substrate which has an irregular structure, much like a sponge, which allows it to better filter the exhaust gases while using less material then the exhaust filters currently in used.
In a basic exhaust cleaning unit, a catalytically active layer – containing expensive noble metals such as platinum, rhodium or palladium – is deposited on the surface of a ceramic substrate. Exhaust gases flow through the catalyst and filtered of harmful substances.
The exhaust gases flow in a regular, non-turbulent manner and, as such, just touch the middle of the catalyst layer. The rest remains untouched and unused.
In the Empa developed substrate, known as FoamCat, the irregular structure of the foam causes the gas passing through to flow in a turbulent manner. This distributes the gas equally throughout the whole layer.
Although FoamCat has less surface area than other filters, the area is much more efficiently utilized, allowing it to achieve the same effect while using only one third of the expensive noble metals.
The foam catalyst is being proven in a diesel test vehicle on the Empa site. It has also been fitted on a vehicle belonging to the Industriellen Werke Basel, which has been driven around in a long-term test over the last 18 months.
With the Euro 6 exhaust-gas standards set to come into force in September 2014, emissions from diesel motors will need to sink significantly. Empa believes its FoamCat will be able to help meet these standards at minimal cost.
Though the foam catalyst is being manufactured purely on the laboratory scale, industrial contacts such as material technologies company Umicore and the Fiat Powertrain Technologies have already expressed interest in FoamCat’s commercialization.