Durable Diesel Filtration

Danish company NoTox A/S has supplied diesel particulate filters for nearly 10 years. Its NoTox Diesel Particulate Filter is manufactured in silicon carbide which, combined with the thermal design, produces a highly durable filter monolith.

The filters are mainly used in the retrofit of heavy duty vehicles, as well as many other applications. According to the company, while most diesel particulate filters are capable of removing soot from the exhaust of diesel vehicles, few have the durability of NoTox’s diesel particulate filters which are able to withstand the very demanding conditions prevailing during filtration of diesel exhaust.

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.
Its XD filters are most often used for filter systems with a passive regeneration strategy, where the filter may encounter very high soot loads before regeneration takes place.

NoTox’s MD filters are used for applications where active regeneration is employed. For this type of applications such as OEM use, 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 the company to produce porous structures with pore sizes from a fewer 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. The permeability of the NoTox material is therefore claimed to be much higher than most competing filter materials, enabling us to provide more robust filters, with the same pressure drop as competing technologies. The raw materials used for the manufacture of NoTox silicon carbide filters are commercial grades of silicon carbide together with organic binders and additives.
Automotive Industries spoke to NoTox Holding’s chief executive officer Lars Frederiksen and asked him what his plans for the company’s future were.

Frederiksen: We are like any supplier in the automotive industry – very focused on lowering costs and securing supply. We therefore need to have our production close to the markets, and are already exploring how to establish ourselves in both the Asian and North American markets.

AI: What are your plans to increase your manufacturing capabilities in Denmark?

Frederiksen: We have just announced the take-over of a production facility which is presently manufacturing brake components. With this facility we plan to establish a large OEM production. OE production will begin in 2007.

AI: Which industry does NoTox get the bulk of its revenues from?

Frederiksen: We are presently getting the bulk revenue from retrofit players, producing filter systems for the off-road and on-road market. The automotive sector represents a significant part of our growth strategy.

AI: What are some of the technological breakthroughs we can expect from NoTox in the near future?

Frederiksen: Particularly in relation to gaining additional benefits, we expect breakthroughs regarding our reduced demand for segmentation compared to other SiC filter technologies. This will result in a further diversification of the NoTox filter range, and offer some competitive advantages that we expect will consolidate and strengthen our technology base further.

AI: How popular is your technology globally?

Frederiksen: We have customers in nearly every region of the world, but our main customer base at present is still in Europe. We are now looking for partners in the US and in Asia.