DE102016110527A1 - Particle filter for an internal combustion engine - Google Patents

Abstract

The invention relates to a particulate filter for an internal combustion engine, comprising a filter body (2), wherein the filter body (2) has a filter inlet (3) and a filter outlet (4), and wherein the filter body (2) has at least one first channel (FIG. 5) with a first inlet (7) facing the filter inlet (3) and a second end (8) facing the filter outlet (4), and a second channel (6) with a third end facing the filter inlet (3) (9) and a filter outlet (4) facing formed fourth end (10), and wherein the second end (8) and the third end (9) are formed hindurchurchströmbar, wherein the channels (5, 6) in a flow-through channel section (13) and an orurchströmbaren channel portion (14) are articulated, and wherein a flow passage of a filter body (2) flowing through the exhaust gas from he Most channel (5) in the second channel (6) via a between the first channel (5) and the second channel (6) formed common channel wall (11), and wherein the channel wall (11) soot particles of the exhaust gas is formed separable. According to the invention, in order to increase a reaction temperature present in the particle filter (1) for burning off the soot particles, the first channel (5) and / or the second channel (6) has a heating element (15), wherein the heating element (15) in the channel section (14) can be flowed through. the channel (5; 6) is arranged.

Description

The invention relates to a particle filter for an internal combustion engine according to the preamble of patent claim 1.

Particulate filters for internal combustion engines, in particular for self-igniting internal combustion engines, are known. The particle filter is characterized in particular by the fact that a plurality of channels are arranged side by side, in particular parallel to one another, the channels being mutually closed. The exhaust gas flowing in via a filter inlet flows through the particle filter in its direction of extent in that it passes from a channel which is open at the filter inlet into a channel which is open at the filter outlet via a porous wall arranged between these two channels. Solid particles of the exhaust gas are deposited in and / or on the wall. Since these particles reduce a free flow cross-section of the particulate filter and because the potential for excessive temperature increases in the particulate filter increases as the load increases due to exothermic soot burnup, these particles are to be removed from the particulate filter by a so-called regeneration, in other words by conversion of the soot particles.

The patent EP 2 161 420 B1 a particulate filter for an internal combustion engine can be removed, which is uncoated in areas of the channels in which predominantly solid particles accumulate. Thus, a coated portion and an uncoated portion are formed in the channels, wherein the uncoated portion of a channel adjacent to the coated portion of another channel is formed.

From the publication EP 1 250 952 A1 is a particulate filter for a trained as a diesel engine combustion engine, which has a coating for soot oxidation, the reaction temperature is below 500 ° C. This is achieved by means of preferred particulate filter materials, in the form of alkaline earth metal compounds, an oxygen-storing substance and platinum, palladium or rhodium.

The patent US 7,691,339 B2 discloses a particulate filter for an internal combustion engine, which uses microwave energy to reduce soot particles accumulating in the particulate filter. In this case, a microwave generator is provided, which warms up received in the soot filter microwave-absorbing material.

The published patent DE 10 2006 032 886 A1 a particulate filter is removable, which has a functional material coating. The channels of the particle filter to be flowed through are coated on their wall surfaces with the functional material, wherein the functional material in an exothermic reaction, starting from a first modification, passes into a second modification and leads to an increase in a temperature present in the particle filter.

The object of the present invention is to provide an improved particulate filter for an internal combustion engine.

This object is achieved by a particulate filter for an internal combustion engine with the features of claim 1. Advantageous embodiments with expedient and non-trivial developments of the invention are specified in the respective subclaims.

A particulate filter according to the invention for an internal combustion engine has a filter body, wherein the filter body has a filter inlet which can be flowed through and a filter outlet which can be flowed through. The filter body comprises at least one first channel which can be flowed through, with a first end facing the filter inlet and a second end facing the filter outlet, and a second channel through which the filter inlet faces with a third end facing the filter inlet and a fourth end facing the filter outlet. The second end and the third end are formed such that they can not be flowed through or flow through them to a certain extent, so that the channels can be divided into a flow-through channel section and a passage section which can be flowed through or, to a certain extent, be difficultly flowed through.

As a result, first channels are formed with obstructed or obstructed flow inlet at the filter inlet and second channels with obstructed or obstructed flow outlet at the filter outlet. A flow passage from the exhaust gas flowing through the particulate filter, starting from the first channel into the second channel, via a common channel wall formed between the first channel and the second channel. The channel wall is formed soot particles of the exhaust gas depositable.

Below is an underflowable channel section is not necessarily a completely sealed and closed against any flow-through channel section to understand, but it is also a somewhat difficult to be flowed through channel section to understand -. As a so-called diffusion-open channel section, in particular oxygen molecules can penetrate this difficult to flow through the channel section.

To increase a reaction temperature present in the particle filter for burning off the soot particles, the first channel and / or the second channel has a heating element, wherein the heating element is arranged in the channel section of the channel which can not be flowed through.

The arrangement of the heating element in the flow-through channel section has several advantages. Thus, for example, a flow through the particle filter due to the heating element, which has a flow resistance, not affected. Another advantage is the use of, with regard to the flow, unused areas of the particulate filter: an increase in the reaction temperature for burning off the soot particles can be achieved while maintaining the original size of the particulate filter. In other words, that means that an intended installation space of the particulate filter is maintained and no constructive modification measures are to be made with regard to the installation space. If, for example, the channels of the particle filter are coated, this may have the consequence that, compared to uncoated channels, a channel cross-section of the channel is reduced due to the coating. However, in order for the uncoated particle filter to be able to achieve corresponding throughflow conditions of the particle filter having the coating, the channel cross section of the particle filter must be increased, as a result of which the required installation space of the particle filter having the coating likewise increases.

In one embodiment of the particle filter according to the invention, the heating element is formed from a functional material which reacts exothermically when oxygen is stored. This means in other words that the heating element is quasi self-igniting. The advantage lies in the fact that it requires only the heating element itself, without, for example, as known from the prior art, an aid in the form of an ignition device, such as. The microwave generator to provide. It is merely the operation of the internal combustion engine to be adjusted so that due to a corresponding temperature of the exhaust gas and / or a corresponding composition of the exhaust gas, the exothermic reaction of the functional material is initiated.

Preferably, the heating element can be excited by means of a change in a combustion air ratio of the exhaust gas for heat dissipation. For this purpose, by adding or reducing fuel or air, the combustion air ratio of the exhaust gas can be changed. In particular, a so-called substoichiometric composition corresponding to a combustion air ratio of less than 1 or a superstoichiometric composition corresponding to a combustion air ratio of greater than 1 is achievable by so-called rich operation of the internal combustion engine or lean operation of the internal combustion engine.

Preferably, the heating element with the aid of a change in the combustion air ratio of the exhaust gas from a combustion air ratio with a value less than 1, can be excited to a combustion air ratio with a value greater than 1 for heat dissipation. This change in the combustion air ratio can be achieved, for example, starting from a load operation of the internal combustion engine at a low stoichiometric operation, for example. At a value of the combustion air ratio of about 0.98 and a subsequent overrun operation of the internal combustion engine, in particular with a fuel cut.

Such an operation of the internal combustion engine can, for example, already be achieved by a downhill or a deceleration of a motor vehicle with the internal combustion engine. This is already at a short time, z. B. due to the downhill or a delay realizable overrun, especially with a fuel cut, a temperature increase due to the heat output of the heating element in the particle filter can be brought. In other words, the heating element can react to a brief lean operation of the internal combustion engine, for example. By fuel cut, with a sharp increase in temperature. The advantage is that an engine control for operating the internal combustion engine does not have to be adjusted or only slightly.

In a further embodiment of the particulate filter according to the invention, the heating element has an element cross section which corresponds to a cross section of the channel. Thus, the heating element, in addition to its temperature-increasing function, be used for one-sided sealing of the channel.

Preferably, the heating element is formed at least on the basis of cerium oxide and / or cerium-zirconium mixed oxides. These oxides have, with appropriate nature and concentration, a pronounced oxygen storage capacity, which can realize a high temperature increase due to the exothermic reaction.

If the heating element contains precious metals such as, for example, palladium and / or rhodium, this also gives them a direct oxygen storage capacity, at least in a certain temperature range.

In a further preferred embodiment of the particulate filter according to the invention, the heating element of the first channel is formed of a first material and the heating element of the second channel is formed of a second material different from the first material. The advantage is the formation of different high temperature increases in the particle filter.

The particle filters of the prior art have, in principle, a comparatively low reaction rate of the burning off of the soot particles. This can have the consequence that, for example due to a burning in all filter areas almost simultaneously incipient at all points of the particulate filter the same soot loading in areas of the particulate filter, which are starting from a filter inlet in the direction of a filter outlet of the particulate filter, very high temperature may possibly lead to damage of the particulate filter and / or any existing coating. In this case, the highest temperature can be in the vicinity of the filter outlet of the particle filter. It is likely that even with z. B. 800 ° C, the burn-up is relatively slow and so the released in the filter inlet heat of the burn is accumulated in the downstream areas, thus also in the area before the filter outlet, with the heat released there.

Thus, with this embodiment, the advantage is given to bring about a rise in temperature in the region of the filter inlet, which differs from the temperature increase in the region of the filter outlet. It is advantageous to form the heating element in the region of the filter inlet of a first material, which releases heat only when present in the particulate filter low and medium temperatures, for example, about 800 ° C, heat, for example palladium, and in the region of the filter outlet, the heating element form a second material, which releases heat even for even higher temperatures present in the particulate filter, for example, with a high proportion of standard storage materials of today's 3-way catalysts.

For example, particulate filters which are highly loaded, e.g. Particulate filters, which have a large amount of soot particles to heat them from the filter outlet. If the burn-up or the regeneration were initiated at the filter outlet, the heat released there would really be released and not imposed in the upstream areas as a "thermal burden". Under certain boundary conditions, in particular if flow velocities are not too high, the so-called Rußabbrandfront would run against the flow velocity in the direction of the filter inlet and in the formed there areas of the particulate filter into it. Therefore, it may be advantageous if the first material is designed for the reaction in a medium temperature range, and the second material is designed to react over a further temperature range.

A further increase of an efficient regeneration can be brought about with the aid of a further heating element, if this is arranged in the flow-through channel section.

In a further embodiment of the invention, the infiltrated channel section has a plug, wherein the heating element is designed to replace the plug completely or partially. Particulate filters according to the prior art have plugs which serve only the purpose of sealing the channel. They are solid and have a relatively long length. For example. For plug filters used or provided in the gasoline engine sector, plug lengths of approx. 7 mm are usual. A mass fraction of the plug is in the clogged filter inlet or filter outlet areas at about 60-70%. Therefore, a complete or partial replacement of these plugs by a heating element made of a material with a high proportion of a storage component with high oxidation heat, to a sharp increase in temperature at a change in the operation of the internal combustion engine from rich operation to lean operation, for example in conjunction with a fuel cut. A particularly efficient particle filter is thus realized.

Further advantages, features and details of the invention will become apparent from the following description of preferred embodiments and from the drawing. The features and feature combinations mentioned above in the description as well as the features and feature combinations mentioned below in the description of the figures and / or in the figures alone can be used not only in the respectively specified combination but also in other combinations or in isolation, without the scope of To leave invention. Identical or functionally identical elements are assigned identical reference numerals. Show it:

1 in a t-λ diagram, a curve of the combustion air ratio λ of exhaust gas and in a corresponding tT diagram temperatures in one Particle filter according to the prior art and in a particulate filter according to the invention temperature profiles at different positions of the particulate filter, determined by means of a simulation calculation,

2 in an xT-diagram temperature profiles at different times in the particulate filter according to the prior art and the particulate filter according to the invention,

3 in a schematic representation of a particulate filter according to the invention, and

4 an Ellingham diagram of the elements palladium and rhodium and their oxides.

A sudden increase in temperature in a particle filter according to the invention 1 is with an exothermic reaction of a material having a high oxygen storage content, at a change in operation of an internal combustion engine, not shown from a load to a push operation brought about. In this case, an internal combustion engine supplied air-fuel mixture is changed in their proportions. Preferably, starting from a so-called rich operation, which has a combustion air ratio λ of the air-fuel mixture with a value less than 1, to change into a lean operation, which has a combustion air ratio λ of the air-fuel mixture with a value greater than 1. As a result, exhaust gas of the internal combustion engine, which the particle filter 1 flows through, an increased oxygen content, which triggers the exothermic reaction. A simultaneous overrun fuel cut significantly increases the oxygen content, which also causes a significant increase in the temperature in the particulate filter 1 is achievable.

1 shows in the lower section in a t-λ diagram a curve L1 of a combustion air ratio λ over the time t before a known particle filter. A sudden change in the combustion air ratio λ from a value of approximately 0.95 here to a value significantly above 1 indicates a point in time at which the internal combustion engine switches over from operation to coasting with fuel cutoff.

In the upper and middle section of the 1 are calculated as a function of the operating change calculated temperature profiles T1, T2, and T3 for different positions along a flow axis of the particulate filter. In the upper section are the temperature curves of a particulate filter 1 according to the prior art and in the middle section of 1 are temperature profiles of a particulate filter according to the invention 1 shown. The temperature profile T0 corresponds to a so-called inlet temperature, ie the gas temperature before OPF.

The particle filter according to the invention 1 which schematically according to 3 is formed, has durchströmbare channel sections 13 and infiltratable channel sections 14 , The temperature curves T1 and T3 show a thermal behavior of the particulate filter 1 in a plane near a filter entrance 3 or near a filter outlet 4 of the particulate filter 1 that is, in planes that also have infiltrated channel sections 14 cut. Temperature curve T2 shows the thermal behavior of the particulate filter 1 near a mid-plane of the particulate filter 1 , which is located midway between the levels of the filter inlet 3 and the filter outlet 4 is trained.

The temperatures T1, T2, T3 in the particle filter 1 According to the prior art follow delayed, due to the heat capacity of the particulate filter 1 itself, the cooling inlet temperature T0. The temperatures T1, T2, T3 in the particle filter according to the invention 1 show other courses. The temperatures T1, T3 of the planes with infiltrated channel sections 14 immediately rise to the change from the (slightly) rich to the lean mixture only imperceptibly decelerates violently, in this example by about 75 ° C. Once an exothermic filling of an oxygen storage in the umurchströmbaren channel sections 14 is completed, follow these temperatures T1, T3 delayed in time the ever colder inlet temperature T0.

The calculations were made without consideration of a Rußabbrandes. Not shown measurements show that at about 700 ° C of the particulate filter 1 The Rußabbrand runs only slowly. At around 850 ° C regeneration of stored soot is clearly visible. For the load case shown here has the particle filter 1 hardly regenerated without soot. The particle filter according to the invention 1 comprising the flow-through channel sections 14 However, ignites the Rußabbrand so that it then expires itself or sustaining until extensive regeneration expires.

2 shows in an xT diagram temperature curves at different times t0, t1, t2, t3, t4 before and after a change from a (light) rich load operation of the internal combustion engine in the overrun with fuel cut in the direction of the flow axis of the particulate filter 1 , In the upper section of 2 are the temperature curves t0, t1, t2, t3, t4 in the particle filter 1 according to the prior art and in the lower section of 2 the temperature curves t0, t1, t2, t3, t4 in the particle filter according to the invention 1 shown.

The temperature curve t0 corresponds to a course before the operating changeover. The temperature profiles t1, t2, t3, t4 are temperature profiles after the changeover of operation, wherein the temperature profile t1 is 20.2 sec., The temperature profile t2 is 21.2 sec., The temperature profile t3 is 22.2 sec and the temperature profile t4 is 23.2 sec Temperature profile over the flow axis after change of operation corresponds.

The particle filter according to the invention 1 for the internal combustion engine, not shown in accordance with a schematic representation 3 educated. During operation of the internal combustion engine, which is embodied in the form of a direct-injection gasoline engine, exhaust gas containing soot particles is produced as a result of combustion of the air-fuel mixture.

The particle filter 1 has a filter body 2 with a flow-through filter inlet 3 and a flow-through filter outlet 4 on. In the filter body 2 is a multitude of channels that can be flowed through 5 . 6 educated. The channels 5 . 6 are along a longitudinal axis L extending, formed adjacent to each other, wherein a flow along the longitudinal axis L takes place.

The channels 5 . 6 alternate at the filter inlet 3 or on the filter outlet 4 locked end up. In the following, by means of a first channel 5 and a second channel 6 the variety of channels and the functioning of the particulate filter 1 described.

The first channel 5 owns the filter inlet 3 facing trained first end 7 and one the filter outlet 4 facing trained second end 8th , The second channel 6 indicates the filter inlet 3 facing trained third end 9 and one the filter outlet 4 facing trained fourth end 10 on. The second end 8th and the third end 9 are formed unblocked. A flow passage of the exhaust gas from the first channel 5 in the second channel 6 via one between the first channel 5 and the second channel 6 trained common canal wall 11 ,

The canal wall 11 is flow-permeable porous, with the soot particles of the channel wall 11 flowing exhaust gas at the channel wall 11 deposit or deposit. The exhaust gas flows through the particle filter 1 in the direction of the arrows.

The channels 5 . 6 are at their unbroken ends 8th . 9 with the help of a plug 12 locked. In other words, that means the channels 5 . 6 in each case a freely flow-through channel section 13 and an air flow passage section 14 exhibit.

The stopper 12 has an element cross-section QE, which is a cross-section Q of the channel 5 ; 6 equivalent. Since in the illustrated embodiment, the channels 5 . 6 have an identical cross section, the element cross section QE also corresponds to a cross section Q of the second channel 6 , In an embodiment not shown, the channels 5 . 6 different cross sections Q on. That means the plug 12 a cross-section Q of the corresponding channel 5 . 6 has adapted trained element cross-section QE.

The element cross-section QE of the plug 12 is in the illustrated embodiment over a length L of the plug 12 constant. Likewise, the element cross section QE could change over its length L. Thus, for example, in a non-illustrated embodiment, the plug 12 a frusto-conical shape with an over the length LE changing element cross-section QE, if the channel 5 ; 6 has a conical shape.

During operation of the internal combustion engine, the soot particles accumulate in the particle filter 1 , wherein an effective flow cross-section of the particulate filter 1 is reduced over time. The reduction of the effective flow cross-section leads to an increase of an exhaust backpressure of the internal combustion engine, which can lead to an increase of charge cycle losses. This in turn would have a constant increase in fuel consumption of the internal combustion engine or with the same fuel consumption, a reduction in the performance of the internal combustion engine result. Thus, depending on a so-called loading of the particulate filter 1 a regeneration of the particulate filter 1 carried out.

For regeneration of the particle filter 1 this has at least one heating element 15 on, which in the flow-through channel section 14 is arranged. The heating element 15 consists of a functional material, which reacts exothermically at an excess of air, in other words gives off heat and thus to a temperature increase in the particle filter 1 leads.

The heating element 15 is in the form of the plug 12 trained and replaced this. Likewise, the heating element could 15 also as part of the plug 12 be educated. It is formed from a material which is formed triggering an oxygen storage an exothermic reaction. In other words, this means that the heating element 15 due to its molecular structure self-releasing heat, provided that an oxygen storage is formed. This means that there is a reaction heat release.

The material is a solid which may be present in at least two modifications. In rich operation of the internal combustion engine, it is at least partially in a reduced modification, the first modification before and goes in a lean operation of the internal combustion engine in an oxidized modification, the second modification. This solid, also called functional material, is preferably a mixed oxide of cerium and zirconium oxides with optionally further substances, such as. Metals and / or earth metals, lanthanum, presodymium, ytterium, and alumina.

Also suitable are the "less precious" noble metals palladium and rhodium, which also have an oxygen storage capacity directly. At higher temperatures, for example, about 900 ° C, they do not oxidize, therefore do not store, and maintain their noble metallic state. It is irrelevant whether it is an exhaust gas with a rich composition corresponding to the rich operation or an exhaust gas with a lean composition corresponding to the lean operation of the internal combustion engine. Rhodium would gem. 4 Rhodium oxide can form up to about 880 ° C and thus can behave subdued up to this temperature.

According to its composition, the functional material for the exothermic reaction may be formed in different temperature ranges. For example. For example, a first material has a composition having a reducing / oxidizing ability in a low and medium temperature range up to about 700 ° C, for example, palladium. A second material has a composition having an exothermic reaction additional in a high temperature range, such as TWC (three-way-catalyst) standard storage materials. In other words, that means that the first material reacts in the particle filter 1 formed low and medium temperatures, and that the second material to the reaction on all in the particulate filter 1 existing temperatures is formed.

Needless to say, all plugs 12 by a heating element 15 be replaced, whereby the regeneration is improved.

Likewise is also a particle filter 1 with several heating elements 15 , which are formed from a single material and / or a material mix are targeted. The positioning of the heating element (s) 15 , inlet side or outlet side, can also be a function of a mounting situation of the particulate filter 1 , close to the engine or remote from the engine.

In a preferred embodiment, not shown, all plugs 12 of the particulate filter 1 by a respective heating element 15 replaced. Another, unspecified illustrated embodiment of the particulate filter according to the invention 1 indicates at the second end 8th the heating element 15 formed from the first material and at the third end 9 the heating element 15 formed of the second material.

Another not shown embodiment of the particulate filter according to the invention has at second ends and third ends, which are located farther from the central longitudinal axis, heating elements made of a first material. At the second ends and third ends, which are closer to the central longitudinal axis, it has heating elements made of a second material or no heating elements.

Also could be in the flow-through channel section 13 another heating element 15 be arranged. This could be formed from a further, different from the first material and the second material material. Ie. in other words, it is made of another material having an oxygen storage ability different from the first material and the second material.

LIST OF REFERENCE NUMBERS

1

particulate Filter

2

filter body

3

filter inlet

4

filter outlet

5

First channel

6

Second channel

7

First end

8th

Second end

9

Third end

10

Fourth end

11

channel wall

12

Plug

13

Flow-through channel section

14

Non-permeable channel section

15

heating element

L

longitudinal axis

LE

length

L1

course

Q

Channel cross section

QE

Element section

T

temperature

T0

inlet temperature

T1

first temperature profile

T2

second temperature profile

T3

third temperature profile

t

Time

t0

Temperature course before operating changeover

t1

Temperature course after change of operation

t2

Temperature course after change of operation

t3

Temperature course after change of operation

t4

Temperature course after change of operation

λ

Combustion air ratio

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 2161420 B1 [0003]
• EP 1250952 A1 [0004]
• US 7691339 B2 [0005]
• DE 102006032886 A1 [0006]

Claims (11)

Particulate filter for an internal combustion engine, with a filter body ( 2 ), wherein the filter body ( 2 ) a flow-through filter inlet ( 3 ) and a flow-through filter outlet ( 4 ), and wherein the filter body ( 2 ) at least one through-flowable first channel ( 5 ) with a filter inlet ( 3 ) facing first end ( 7 ) and a filter outlet ( 4 ) facing the second end ( 8th ), and a flow-through second channel ( 6 ) with a filter inlet ( 3 ) facing third end ( 9 ) and a filter outlet ( 4 ) facing fourth end ( 10 ), and wherein the second end ( 8th ) and the third end ( 9 ) are formed umströmströmbar, wherein the channels ( 5 . 6 ) in a flow-through channel section ( 13 ) and an air passage section ( 14 ) are articulated, and wherein a flow passage of the filter body ( 2 ) flowing exhaust gas from the first channel ( 5 ) into the second channel ( 6 ) over one between the first channel ( 5 ) and the second channel ( 6 ) formed common channel wall ( 11 ), and wherein the channel wall ( 11 ) Soot particles of the exhaust gas is formed separable, characterized in that to increase one in the particulate filter ( 1 ) present reaction temperature for burning off the soot particles of the first channel ( 5 ) and / or the second channel ( 6 ) a heating element ( 15 ), wherein the heating element ( 15 ) in the flow-through channel section ( 14 ) of the channel ( 5 ; 6 ) is arranged. Particulate filter according to claim 1, characterized in that the heating element ( 15 ) is formed of a functional material which reacts exothermically in an oxygen storage. Particulate filter according to claim 1 or 2, characterized in that the heating element ( 15 ) is excitable by means of a change of a combustion air ratio (λ) of the exhaust gas for heat dissipation. Particulate filter according to claim 3, characterized in that the heating element ( 15 ) by means of a change of a combustion air ratio (λ) of the exhaust gas from a combustion air ratio (λ) with a value less than 1 to a value greater than 1 can be excited for heat dissipation. Particulate filter according to one of the preceding claims, characterized in that the heating element ( 15 ) has an element cross section (QE) which corresponds to a cross section (Q) of the channel (Q) 5 . 6 ) corresponds. Particulate filter according to one of the preceding claims, characterized in that the heating element ( 15 ) is formed at least from cerium and zirconium oxides and / or their mixed oxides. Particulate filter according to one of the preceding claims, characterized in that the heating element ( 15 ) Has palladium and / or rhodium. Particulate filter according to one of the preceding claims, characterized in that the heating element ( 15 ) of the first channel ( 5 ) is formed of a first material and the heating element ( 15 ) of the second channel ( 6 ) is formed of a different from the first material second material. Particulate filter according to claim 8, characterized in that the first material for the reaction in the particulate filter ( 1 ) is formed, and the second material for reaction over all in the particulate filter ( 1 ) present temperatures is formed. Particulate filter according to one of the preceding claims, characterized in that a further heating element ( 15 ) is arranged in the flow-through channel section. Particulate filter according to one of the preceding claims, characterized in that the non-flowable passage section comprises a plug ( 12 ), wherein the heating element ( 15 ) the plug ( 12 ) is formed completely or partially replacing.

Images