C a t a l y s t s p o s i t i o n e d b e f o r eTu r b o C h a r g e r i n d i e s e l e n g i n e s

Turbulence and higher temperaturesincrease efficiencyThe sales share of modern turbo-diesel-cars has reached a level of almost 50percent across the whole of Europe andthis figure is still rising. The low exhaustgas temperatures in diesel engines,however, make it difficult to achievean even more effective conversion ofpollutants as required for EU IV levelsin 2005.

The solution to this technical challengelies with the Pre-Turbo-Catalyst fromEMITEC.

Gesellschaft für Emissionstechnologie mbH

Hauptstraße 128D-53797 LohmarTelephone +49 2246 109 - 0Telefax +49 2246 109-109

USA:

3250 University Drive, Suite 100Auburn Hills, Michigan 48326-2390Telephone +1 248 276-6430Telefax +1 248 276-6431

Japan:

Sumitomo Seimei Shin-OsakaHigashiguchi Bldg. 8F,1-19-4, Higashi-Nakajima,Higashi-Yodogawa-kuOsaka 533-0033Telephone +81 6 6325-0931/0941/0981Telefax +81 6 6325-0996

Sigma Bldg. 1F,3-7-12, Shibaura, Minato-ku, Tokyo 108-0023Telephone +81 3 5476-5901Telefax +81 3 5476-5906

India:

Emitec Emission Controls Pvt. Ltd.Office #503, 5th Floor413-B, EDEN HALLGokhale Road,Shivaji NagarPune 411 016Telephone +91 20 5671635Telefax +91 20 5671635

China:

Emitec Gesellschaft für Emissionstechnologie mbHBeijing Representative Office: Beijing Office No. 3Mai Zi Dian Xi Road, Chao Yang District, Beijing P.R. ChinaBeijing Towercrest Plaza, Room 919Post code: 100016Telephone +86 10 64674354Telefax +86 10 64674261

South Korea:

Korean Emitec Representative Office:Korea Techcon Co. Ltd.Yeosan Building, Room 501668-4 Yeoksam-dongKangnam-Ku135-010 SeoulTelephone +82 2 5019091Telefax +82 2 5019093

Temperatures in the European Emission Test Cycle for a vehicle with diesel engine at the catalystpositions ‘underfloor’ (UF), ‘close-coupled catalyst’ (CCC) and ‘pre-turbo-charger’ (PTC).

Because of the high efficiency of the pre-turbo catalyst, any additional catalystsafter the turbo charger can be designedsignificantly smaller.

This lowers system and coating costs.

Optimum set-up of a catalyst systempost turbo-charger

Since, to a large extent, HC and CO havealready been oxidized before the turbo-charger due to the addition of a PTC, anysubsequent catalysts can be design opti-mized to perform new functions. Veryoften the formation of NO2 is a significantstep, for example in the oxidation of sootparticles or even in the reduction ofnitrogen oxide using selective catalyticreduction (SCR technology). Here too,the use of the PTC leads to significantreductions in the overall catalyst volume.

The PTC-System

PTC-catalysts can be used in variouspositions in front of the turbo-charger:

- in the cylinder head ports:PTC-C(ylinderhead)

- in the manifold:PTC-M(anifold)

- directly in front of the turbine:PTC-T(urbine)

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200 cpsi - turbulent200 cpsi - laminar

PTC: The Pre-Turbo-Charger-Catalyst-System from Emitec

Small and effective

In front of the exhaust gas turbinetemperatures are approximately 100 °Chigher than behind the turbo-chargerdue to the "heat sink” effect. Via thispositioning a small-volume Metalit ofonly 20 to 120 cm3 (depending on enginesize) meets the HC and CO conversionrates as reliably as a considerably largerpost-turbo-charger catalyst.

Turbulence increases efficiency

For the first time in the history ofautomobile emission technology,turbulence is being used to increaseefficiency. The turbulence means thatthe pollutant molecules will – withincreased probability – reach the activecentres of the catalytic coatingcontaining precious metals.

Turbulence is beingused to increaseefficiency

Pre-turbine positionmeans higher

temperatures andgreater efficiency

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For further information contact EMITEC.

Operative range CCCand UF-catalysts

Operative rangePTC