Silicon Carbide filter technology

Danish company NoTox A/S is one of the most innovative participants at the IAA fair in Hanover this September. The company, which manufactures diesel particulate filters, is part of Scandinavian Brake Systems (SBS). NoTox’s Diesel Particulate Filter, is made using silicon carbide which the company claims, combined with a thermal design, offers the best durability.

It will be interesting to see whether NoTox will get a good reaction after Hanover which could pave the way for the company to play an important role in the Manufacturers of Emission Controls Association or MECA. MECA is a non-profit association headquartered in Washington DC. Formed in 1976, it provides the latest technical information on emission control technology for motor vehicles. MECA’s members include manufacturers of emission control equipment, automobiles, trucks and buses and off-road vehicles and stationary sources.

Some of the products MECA members manufacture include catalytic converters catalysts, substrates, mounting sleeves, and converter housings for all fuels, diesel particulate filters, oxygen, NOx, and temperature sensors, thermal management strategies, engine/fuel management technologies, crankcase emission control technologies, evaporative emission controls, enhanced combustion technologies, plasma/corona technologies and components for fuel cell technology. The stationary products include selective catalytic reduction (SCR) systems, non-selective catalytic reduction (NSCR) systems, diesel particulate filters and catalytic oxidation systems.

MECA’s mission is to provide information on emission controls and how to retrofit vehicles the necessary equipment to cut emissions. And NoTox is in the business of retrofitting diesel vehicles with filters to cut emissions.

In a demonstration in 1998, NoTox fitted a city bus with a filter system based on NoTox XD-90 filter substrate. The bus was in service until 2003, with the same filter substrate in place. The filter reached more than 700.000 km, without any deterioration of the filter.

The NoTox ceramic technology comprises a thorough understanding of the chemical and physical reactions involved in creating a highly porous structure of recrystallized silicon carbide. NoTox offers silicon carbide wall flow filters (WFF), primarily used for soot filtration in engine exhaust. The honeycomb design is also suitable as catalyst support, bed material for chemical reactors and other applications.

NoTox manufactures its filters in two different versions, each targeted at different applications. According to the company, the filtration efficiency is above 97% in all the filter versions. NoTox’s MD filters are often used for applications where active regeneration is employed. For this type of applications, where regeneration takes place under controlled conditions, a filter with less durability is required. This enables a filter design with more attention on reducing the pressure drop as much as possible.

NoTox was the first to patent the technology that extrudes and fires coarse grained silicon carbide. This enabled NoTox to produce porous structures with pore sizes from a few microns up to more than 100 microns. Such a porous structure, constituted of particles, bonded together in the contact points, has a 100% open porosity, and no dead-end pores. Automotive Industries spoke to Lars Tinggaard Johannesen, NoTox’s Sales Director and asked him what he feels about the company’s participation in the Hanover fair and the growth prospects for their valuable contribution to the industry.

AI: What are some of the technologies your company is exhibiting this year in Hanover?

We are attending the IAA fair in cooperation with one of our preferred catalytic partners, Ecocat, and our prime focus continues to be our Silicon Carbide filter technology which in performance and durability exceeds other competing technologies.

AI: What kind of response do you expect from displaying NoTox’ products at the IAA fair?

We are experiencing a growing responsiveness to our technology and we expect this interest to be elevated at the IAA. We have entered into crucial dialogue with a number of OEMs and we anticipate these discussions to result in the selection of our technology for both heavy duty vehicles as well as light vehicles.

AI: How successful have your displays been at previous fairs such as SAE World Expo in Detroit?

Our displays have been tremendously successful and exceeded our most optimistic expectations. This reception in the market place endorses our belief in the growth strategy we have set in motion for our product and technology.

AI: Are you planning to participate in future OE shows in 2007? If so, what reaction do you hope to get?

We will most definitely be present at the most important OE shows in 2007. The focus on emissions from all OEMs and Tier 1s is so strong that we expect a huge interest in our products. We also expect to strengthen the dialogue which we are engaged in with a number of significant OEMs.

AI: Any plans to become a member of MECA and how important would it be for your company to gain membership into such an association?

MECA is an important association for promoting an understanding of its member’s emission control technologies and we therefore consider it central to participate in their efforts.