JP2010284599A - Honeycomb support for exhaust gas purification catalyst - Google Patents

Honeycomb support for exhaust gas purification catalyst Download PDF

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JP2010284599A
JP2010284599A JP2009140747A JP2009140747A JP2010284599A JP 2010284599 A JP2010284599 A JP 2010284599A JP 2009140747 A JP2009140747 A JP 2009140747A JP 2009140747 A JP2009140747 A JP 2009140747A JP 2010284599 A JP2010284599 A JP 2010284599A
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exhaust gas
cell density
honeycomb carrier
purification catalyst
density portion
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Masahiko Takeuchi
雅彦 竹内
Takeshi Yamauchi
剛 山内
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Toyota Motor Corp
Nippon Steel Chemical and Materials Co Ltd
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Nippon Steel Materials Co Ltd
Toyota Motor Corp
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Abstract

<P>PROBLEM TO BE SOLVED: To reduce exhaustion noise and exhaustion pressure loss while retaining the purification performance of a catalyst at a high level by improving the structure of the honeycomb support itself. <P>SOLUTION: A low-cell-density portion 12 lower in cell density than in the upstream is formed in the downstream in the flowing direction of exhaust gas. The passage for exhaust gas is expanded when exhaust gas flowing into the upstream flows into the low-cell-density portion 12, leading to a silencing effect due to expansion of the passage, like in common silencers, and the reduction of the pressure loss. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

本発明は、自動車の排ガス浄化用触媒などに用いられるハニカム担体に関し、詳しくは排気騒音を低減できるハニカム担体に関する。   The present invention relates to a honeycomb carrier used for an exhaust gas purification catalyst for automobiles, and more particularly to a honeycomb carrier capable of reducing exhaust noise.

排ガス浄化用触媒に用いられる担体基材として、触媒と排ガスとの接触面積を高めるためにハニカム担体が広く知られている。このハニカム担体は、多数のセル通路を有するハニカム形状のものであり、コージェライトなどの耐熱セラミック製あるいはメタル製などのものが知られている。そして近年の排ガス規制の強化に伴い、ハニカム担体はセル密度が益々高まっている。ここでセル密度とは、排ガス流れ方向に対して直角方向の断面における単位面積あたりのセル通路の数をいう。セル密度が高くなるほど、セル隔壁にコートされる触媒と排ガスとの接触面積が増大するので、浄化性能が向上する。   Honeycomb carriers are widely known as carrier substrates used in exhaust gas purification catalysts in order to increase the contact area between the catalyst and the exhaust gas. This honeycomb carrier has a honeycomb shape having a large number of cell passages, and those made of heat-resistant ceramics such as cordierite or metal are known. As the exhaust gas regulations are strengthened in recent years, the cell density of the honeycomb carrier has been increasing. Here, the cell density means the number of cell passages per unit area in a cross section perpendicular to the exhaust gas flow direction. As the cell density increases, the contact area between the catalyst coated on the cell partition walls and the exhaust gas increases, so the purification performance improves.

ところがセル密度が高くなるほど、排ガス浄化用触媒を通過する際の排ガスへの抵抗が増大するために、排気騒音が増大し、排気圧損も増大するという問題があった。しかし浄化性能を犠牲にしてまで排気騒音や圧損を低減することはできない。   However, as the cell density increases, the resistance to the exhaust gas when passing through the exhaust gas purification catalyst increases, so that there is a problem that exhaust noise increases and exhaust pressure loss also increases. However, exhaust noise and pressure loss cannot be reduced until sacrificing purification performance.

そこで特開平04ー269321号公報には、エキゾーストマニホールドと触媒コンバータとの間に膨張室を設けた排気ガス消音装置が提案されている。この発明によれば、膨張室で音響エネルギーが減衰した排ガスが触媒コンバータに流入するので、触媒コンバータからの放射音を低減することができる。   Japanese Laid-Open Patent Publication No. 04-269321 proposes an exhaust gas silencer in which an expansion chamber is provided between the exhaust manifold and the catalytic converter. According to the present invention, the exhaust gas whose acoustic energy is attenuated in the expansion chamber flows into the catalytic converter, so that the radiated sound from the catalytic converter can be reduced.

また特開2002ー129953号公報には、チェーンソーなど持ち運び可能な作業機器用に、触媒を内包した排気消音器が記載され、触媒の温度が所定温度以上となった場合にバイパス穴を開くことが記載されている。   Japanese Patent Laid-Open No. 2002-129953 describes an exhaust silencer containing a catalyst for a portable working device such as a chainsaw, which can open a bypass hole when the temperature of the catalyst exceeds a predetermined temperature. Are listed.

しかしながら従来の技術には、ハニカム担体自体の構造を改良することで、排気騒音を低減する技術は見あたらない。   However, in the prior art, there is no technique for reducing exhaust noise by improving the structure of the honeycomb carrier itself.

特開平04ー269321号公報JP 04-269321 A 特開2002ー129953号公報Japanese Patent Laid-Open No. 2002-129953

本発明は上記事情に鑑みてなされたものであり、ハニカム担体自体の構造を改良することで、排ガス浄化用触媒の浄化性能は高く維持しつつ、排気騒音及び排気圧損を低減することを解決すべき課題とする。   The present invention has been made in view of the above circumstances, and solves the problem of reducing exhaust noise and exhaust pressure loss while improving the purification performance of the exhaust gas purification catalyst by improving the structure of the honeycomb carrier itself. It should be a challenge.

上記課題を解決する本発明のハニカム担体の特徴は、複数のセル通路をもつストレートフロー構造をなし内燃機関からの排ガスを浄化する排ガス浄化用触媒に用いられる排ガス浄化触媒用ハニカム担体であって、排ガス流れ方向における下流側には、排ガス流れ方向に対して直角方向の断面における単位面積あたりのセル通路の数であるセル密度が上流側より低密度の低セル密度部をもつことにある。   A feature of the honeycomb carrier of the present invention that solves the above problems is a honeycomb carrier for an exhaust gas purification catalyst used for an exhaust gas purification catalyst that purifies exhaust gas from an internal combustion engine having a straight flow structure having a plurality of cell passages, On the downstream side in the exhaust gas flow direction, the cell density, which is the number of cell passages per unit area in a cross section perpendicular to the exhaust gas flow direction, has a low cell density portion having a lower density than the upstream side.

本発明のハニカム担体を用いた排ガス浄化用触媒によれば、排ガス流入側端面から流入した排ガスが高セル密度部から低セル密度部に流入することで、排ガス流路が拡張される。したがって一般的な消音器と同様に、流路の拡張による消音効果が発現される。   According to the exhaust gas purifying catalyst using the honeycomb carrier of the present invention, the exhaust gas flow path is expanded by the exhaust gas flowing from the exhaust gas inflow side end surface flowing from the high cell density portion to the low cell density portion. Therefore, as with a general silencer, a silencing effect due to expansion of the flow path is exhibited.

そしてハニカム担体内の平均セル密度が小さくなるので、ハニカム担体あたりの圧損上昇が抑制される。そのため排気系全体での消音のために必要になる圧損に余裕ができ、排気系全体での消音性能に対して低圧損で消音が実現できる。   Since the average cell density in the honeycomb carrier is reduced, an increase in pressure loss per honeycomb carrier is suppressed. Therefore, there can be enough pressure loss necessary for noise reduction in the entire exhaust system, and noise reduction can be realized with low pressure loss with respect to the noise reduction performance in the entire exhaust system.

また排ガス浄化性能に影響の大きな上流部では、高セル密度のままとすることができるので、排ガス浄化性能を損なうこともない。   Further, in the upstream portion, which has a large influence on the exhaust gas purification performance, the high cell density can be maintained, so that the exhaust gas purification performance is not impaired.

さらに本発明のハニカム担体を排ガス浄化用触媒に用いることで、自動車の排気管に備えられる消音器を小型化できる可能性も大きい。また排気管全体の圧損レベルを低減できるので、エンジン出力性能の向上も期待される。   Furthermore, by using the honeycomb carrier of the present invention as an exhaust gas purification catalyst, there is a great possibility that the silencer provided in the exhaust pipe of an automobile can be miniaturized. Moreover, since the pressure loss level of the entire exhaust pipe can be reduced, an improvement in engine output performance is also expected.

本発明の一実施例に係るハニカム担体の模式的な平面図である。1 is a schematic plan view of a honeycomb carrier according to an embodiment of the present invention. 本発明の一実施例に係るハニカム担体に用いた波板の部分斜視図である。It is a fragmentary perspective view of the corrugated sheet used for the honeycomb support | carrier which concerns on one Example of this invention. 本発明の第二の実施例に係るハニカム担体の模式的な説明図である。FIG. 6 is a schematic explanatory view of a honeycomb carrier according to a second embodiment of the present invention. 本発明の第二の実施例に係るハニカム担体に用い平波板の部分平面図である。It is a partial top view of a flat wave board used for the honeycomb support concerning the 2nd example of the present invention. 排気圧損と音圧レベルを相対的に示すグラフである。It is a graph which shows an exhaust pressure loss and a sound pressure level relatively. NOx浄化率と音圧レベルとを示すグラフである。Is a graph showing the the NO x purification rate and the sound pressure level.

本発明のハニカム担体は、排ガス流れ方向における下流側に、セル密度が上流側より低密度の低セル密度部をもつ。すなわち低セル密度部の上流側には、セル密度が低セル密度部より高い高セル密度部が形成されている。高セル密度部のセル密度は、自動車に用いられる一般的な三元触媒の場合と同様の 500〜 700セル/in2 程度とすることが好ましい。したがって低セル密度部のセル密度は、それより低ければよいが、 300〜 500セル/in2 とするのが好ましい。 The honeycomb carrier of the present invention has a low cell density portion whose cell density is lower than that of the upstream side on the downstream side in the exhaust gas flow direction. That is, a high cell density portion having a cell density higher than that of the low cell density portion is formed on the upstream side of the low cell density portion. The cell density of the high cell density portion is preferably about 500 to 700 cells / in 2 as in the case of a general three-way catalyst used in automobiles. Therefore, the cell density of the low cell density portion may be lower than that, but is preferably 300 to 500 cells / in 2 .

低セル密度部は、ハニカム担体の排ガス流出側端面から流入側端面へ向かって、ハニカム担体全長の20〜50%の長さ範囲に形成することが望ましい。この場合、高セル密度部は流入側端面から全長の50〜80%の範囲に形成されることになる。低セル密度部の形成範囲が、流出側端面から全長の20%に満たないと騒音低減効果が不足する。また低セル密度部が流出側端面から50%を超えて形成されると、排ガス浄化性能が低下するようになる。なお低セル密度部は、内周から外周まで形成してもよいし、外周部のみあるいは内周部のみに形成することもできる。   The low cell density portion is desirably formed in a length range of 20 to 50% of the total length of the honeycomb carrier from the exhaust gas outlet side end surface of the honeycomb carrier to the inflow side end surface. In this case, the high cell density portion is formed in the range of 50 to 80% of the entire length from the inflow side end face. If the formation range of the low cell density part is less than 20% of the total length from the outflow side end face, the noise reduction effect will be insufficient. Further, when the low cell density portion is formed to exceed 50% from the outflow side end face, the exhaust gas purification performance is lowered. The low cell density portion may be formed from the inner periphery to the outer periphery, or may be formed only on the outer periphery or only on the inner periphery.

本発明に係るハニカム担体は、コージェライト、アルミナ、SiC、SiNなどの耐熱性セラミックス、あるいは金属から製造することができる。低セル密度部を形成するには、以下のようにいくつかの方法がある。   The honeycomb carrier according to the present invention can be manufactured from heat-resistant ceramics such as cordierite, alumina, SiC, SiN, or metal. There are several methods for forming the low cell density portion as follows.

セラミックスから製造するには、まず従来のように粘土状スラリーを押出成形してセル通路を形成した後、下流側のセル隔壁を適宜除去して複数のセル通路を連結することで製造することができる。あるいは押出成形時にダイスを交換することで低セル密度部を形成することも可能である。   In order to manufacture from ceramics, it is possible to manufacture by first forming a cell passage by extruding a clay-like slurry as in the past, and then connecting a plurality of cell passages by appropriately removing downstream cell partition walls. it can. Alternatively, the low cell density portion can be formed by exchanging the dies during extrusion molding.

また金属製のメタルハニカム担体の場合には、低セル密度部をさらに容易に形成することができる。メタルハニカム担体を製造するには、箔状の平板と、平板をコルゲート加工してなる波板とを重ねて巻回することで製造されるのが一般的である。この際に、波高さが一端側より他端側が高い波板を用いれば、巻回後には他端側で全体断面積とセル通路の断面積が大きなメタルハニカム担体が形成され、セル数は両端で同一であるので、他端側にセル密度が上流側より低密度の低セル密度部が形成される。あるいは波ピッチが一端側より他端側が大きな波板を用いてもよい。   In the case of a metal metal honeycomb carrier, the low cell density portion can be formed more easily. In general, a metal honeycomb carrier is manufactured by stacking and winding a foil-like flat plate and a corrugated plate obtained by corrugating the flat plate. At this time, if a corrugated plate whose wave height is higher on the other end side than on one end side is used, a metal honeycomb carrier having a large overall cross-sectional area and a cell channel cross-sectional area is formed on the other end side after winding. Therefore, a low cell density portion having a cell density lower than that of the upstream side is formed on the other end side. Alternatively, a corrugated plate having a wave pitch larger on the other end side than on one end side may be used.

また、波板又は平板の一端部から他端部側へ延びるスリット又は切欠きを形成しておき、それを巻回してメタルハニカム担体を製造すれば、一端部側ではスリットによって複数のセル通路が連通し複数のセル通路どうしが結合される。これにより一端部側ではセル通路の数が他端部より少なくなり、一端部側に低セル密度部が形成される。   Moreover, if a slit or notch extending from one end of the corrugated plate or flat plate to the other end is formed and wound to produce a metal honeycomb carrier, a plurality of cell passages are formed by slits on one end. A plurality of cell passages are connected to each other. As a result, the number of cell passages on one end side is smaller than that on the other end, and a low cell density portion is formed on one end side.

以下、実施例及び比較例により本発明を具体的に説明する。   Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples.

図1に本実施例に係るハニカム担体を示す。このハニカム担体1はメタルハニカム担体であり、複数のセル通路10を有している。全体の径は排ガス上流側が小径で下流側が大径となっている。またセル通路10の径も、排ガス上流側がφ 112mmの小径で下流側がφ 135mmの大径となっている。セル通路10の数は上流側も下流側も同一であるので、上流側にセル密度が 600セル/in2 の高セル密度部11が形成され、下流側にセル密度が 400セル/in2 の低セル密度部12が形成されている。 FIG. 1 shows a honeycomb carrier according to this example. The honeycomb carrier 1 is a metal honeycomb carrier and has a plurality of cell passages 10. The overall diameter is small on the upstream side of the exhaust gas and large on the downstream side. Also, the diameter of the cell passage 10 is a small diameter of 112 mm on the exhaust gas upstream side and a large diameter of 135 mm on the downstream side. Since the number of cell passages 10 is the same on the upstream side and the downstream side, a high cell density portion 11 having a cell density of 600 cells / in 2 is formed on the upstream side, and a cell density of 400 cells / in 2 is formed on the downstream side. A low cell density portion 12 is formed.

ハニカム担体1の全長は 118mmであり、高セル密度部11は排ガス流入側端面から50mmの長さの範囲に形成されている。また低セル密度部12は、排ガス流出側端面から50mmの長さの範囲に形成されている。高セル密度部11と低セル密度部12の間には、長さ18mmの傾斜セル部13が形成されている。   The total length of the honeycomb carrier 1 is 118 mm, and the high cell density portion 11 is formed in a range of 50 mm from the end face on the exhaust gas inflow side. The low cell density portion 12 is formed in a range of a length of 50 mm from the end surface on the exhaust gas outflow side. Between the high cell density part 11 and the low cell density part 12, an inclined cell part 13 having a length of 18 mm is formed.

このハニカム担体1は、以下のようにして製造された。まず厚さ50μmのステンレス製金属箔からなる平板と、その平板をコルゲート加工することで形成された波板2を用意した。ここで波板2は、図2に示すように、一端側に波高さが低い一般波部20と、他端側に波高さが高い高波部21とが形成され、一般波部20と高波部21との間には波高さが徐々に変化する傾斜波部22が形成されている。   This honeycomb carrier 1 was manufactured as follows. First, a flat plate made of a stainless steel metal foil having a thickness of 50 μm and a corrugated plate 2 formed by corrugating the flat plate were prepared. Here, as shown in FIG. 2, the corrugated plate 2 is formed with a general wave portion 20 having a low wave height on one end side and a high wave portion 21 having a high wave height on the other end side. An inclined wave portion 22 in which the wave height gradually changes is formed between the two.

そして平板と波板2とを重ねてロール状に巻回し、その際に平板については外周で段差を設けながら巻回し、最後に平板と波板との接触部をスポット溶接によって接合して、本実施例のハニカム担体1を製造した。   Then, the flat plate and the corrugated plate 2 are overlapped and wound into a roll shape. At that time, the flat plate is wound while providing a step at the outer periphery, and finally the contact portion between the flat plate and the corrugated plate is joined by spot welding. The honeycomb carrier 1 of the example was manufactured.

図3に本実施例に係るハニカム担体を示す。このハニカム担体3はメタルハニカム担体であり、複数のセル通路30を有している。セル通路30の数は排ガス上流側で多く下流側で少なく、排ガス流入側端面から2/3の長さ範囲にセル密度が 600セル/in2 の高セル密度部31が形成され、排ガス流出側端面から1/3の長さ範囲にセル密度が 400セル/in2 の低セル密度部32が形成されている。 FIG. 3 shows a honeycomb carrier according to this example. The honeycomb carrier 3 is a metal honeycomb carrier and has a plurality of cell passages 30. The number of the cell passages 30 is large on the exhaust gas upstream side and small on the downstream side, and a high cell density portion 31 having a cell density of 600 cells / in 2 is formed in the length range of 2/3 from the end surface of the exhaust gas inflow side. A low cell density portion 32 having a cell density of 400 cells / in 2 is formed in a 1/3 length range from the end face.

このハニカム担体3は、以下のようにして製造された。図4に示すように、実施例1と同様の平板4の一端部に全幅寸法に対して約1/3の40mmの長さで、幅2mmのスリット40をピッチ12mmで形成した。この平板4と、全幅に一般波部20のみが形成されたこと以外は実施例1と同様の波板2とを用い、実施例1と同様にロール状に巻回し接合して本実施例のハニカム担体とした。排ガス流出側端面から1/3の長さ範囲では、スリット40によって複数のセル通路どうしが連通し結合された結果、その範囲にセル密度が 400セル/in2 の低セル密度部32が形成された。
[比較例1]
実施例1で用いた平板と実施例2で用いた波板とを重ねて巻回し、最後に平板と波板との接触部を接合して、本比較例のハニカム担体を製造した。セル密度は、全長均一で 600セル/in2 である。
The honeycomb carrier 3 was manufactured as follows. As shown in FIG. 4, slits 40 having a length of 40 mm, which is about 1/3 of the total width, were formed at one end of a flat plate 4 similar to that of Example 1 with a pitch of 12 mm. Using this flat plate 4 and the corrugated plate 2 similar to that of the first embodiment except that only the general wave portion 20 is formed in the entire width, it is wound in a roll shape and joined in the same manner as in the first embodiment. A honeycomb carrier was obtained. In the 1/3 length range from the exhaust gas outflow side end surface, a plurality of cell passages are connected and connected by the slit 40, and as a result, a low cell density portion 32 having a cell density of 400 cells / in 2 is formed in the range. It was.
[Comparative Example 1]
The flat plate used in Example 1 and the corrugated plate used in Example 2 were overlapped and wound, and finally the contact portion between the flat plate and the corrugated plate was joined to produce a honeycomb carrier of this comparative example. The cell density is 600 cells / in 2 with a uniform overall length.

<試験例・評価>
各実施例及び比較例1のハニカム担体に、以下のようにして触媒コート層をそれぞれ形成した。
<Test examples and evaluation>
A catalyst coat layer was formed on the honeycomb carrier of each Example and Comparative Example 1 as follows.

まずアルミナにPtが担持されたPt/Al2O3 触媒粉末と、ジルコニアにRhが担持されたRh/ZrO2触媒粉末と、セリアージルコニア複合酸化物粉末と、バインダとしてのアルミナゾルとを、イオン交換水と混合してスラリーを調製した。このスラリーに各ハニカム担体を浸漬し、引き上げて余分なスラリーを吹き払った後、乾燥、焼成して触媒コート層を形成した。触媒コート層は、それぞれのハニカム担体の1リットルあたり 240g形成され、Pt及びRhはそれぞれのハニカム担体の1リットルあたり1g及び 0.3g担持されている。 First, Pt / Al 2 O 3 catalyst powder in which Pt is supported on alumina, Rh / ZrO 2 catalyst powder in which Rh is supported on zirconia, ceria-zirconia composite oxide powder, and alumina sol as a binder are ionized. A slurry was prepared by mixing with exchange water. Each honeycomb carrier was immersed in this slurry and pulled up to blow off excess slurry, and then dried and fired to form a catalyst coat layer. The catalyst coat layer is formed in an amount of 240 g per liter of each honeycomb carrier, and Pt and Rh are supported on 1 g and 0.3 g per liter of each honeycomb carrier.

触媒コート層が形成された各ハニカム担体を 2.4Lのエンジンベンチの排気系にそれぞれ装着し、ハニカム担体前後の排ガス圧力差から圧損を測定した。また触媒コート層が形成された各ハニカム担体をモータ式ブロワーに接続し、騒音計によって音圧レベルを測定した。比較例1の測定値に対する相対値として結果を図5に示す。   Each honeycomb carrier on which the catalyst coat layer was formed was mounted on the exhaust system of a 2.4 L engine bench, and the pressure loss was measured from the exhaust gas pressure difference before and after the honeycomb carrier. Each honeycomb carrier on which the catalyst coat layer was formed was connected to a motor type blower, and the sound pressure level was measured with a noise meter. The results are shown in FIG. 5 as relative values with respect to the measured values of Comparative Example 1.

図5より、実施例1、2に係るハニカム担体によれば、比較例1に係る従来のハニカム担体に比べて圧損ばかりでなく騒音も低減されることが明らかである。   From FIG. 5, it is clear that according to the honeycomb carriers according to Examples 1 and 2, not only the pressure loss but also noise is reduced as compared with the conventional honeycomb carrier according to Comparative Example 1.

スリット40の形成長さを、全幅寸法に対して約21%(25mm)、50%(59mm)、約72%(85mm)の長さとしたこと以外は実施例2と同様の平板と、実施例2で用いた波板とを重ねてそれぞれ巻回し、最後に平板と波板との接触部を接合して、低セル密度部32の長さが異なること以外は同一の複数種のハニカム担体を製造した。これらのハニカム担体と、実施例2及び比較例1のハニカム担体に、上記試験例と同様にして触媒コート層を形成した。   A flat plate similar to that of Example 2 except that the length of the slit 40 is about 21% (25 mm), 50% (59 mm), and about 72% (85 mm) with respect to the entire width dimension. The corrugated sheets used in No. 2 are overlapped and wound respectively, and finally the contact portions between the flat plates and the corrugated sheets are joined, and the same plural types of honeycomb carriers are formed except that the length of the low cell density portion 32 is different. Manufactured. Catalyst coat layers were formed on these honeycomb carriers and the honeycomb carriers of Example 2 and Comparative Example 1 in the same manner as in the above test example.

得られたそれぞれの触媒を 2.4Lのエンジンベンチの排気系にそれぞれ装着し、上記試験例と同様にして音圧レベルを測定するとともに、定常走行時のNOx 浄化率をそれぞれ測定した。結果を図6に示す。 Each of the obtained catalysts was attached to the exhaust system of a 2.4 L engine bench, and the sound pressure level was measured in the same manner as in the above test example, and the NO x purification rate during steady running was also measured. The results are shown in FIG.

図6より、低セル密度部32を設けた各実施例によれば、比較例1に比べて音圧レベルが低下し騒音を低減できることが明らかである。更に、スリットの長さが全長の20%〜50%の範囲内であれば、NOx 浄化率を高く維持しつつ騒音を低減することができることもわかる。 From FIG. 6, it is clear that according to each example in which the low cell density portion 32 is provided, the sound pressure level is lowered and noise can be reduced as compared with Comparative Example 1. It can also be seen that if the slit length is in the range of 20% to 50% of the total length, noise can be reduced while maintaining a high NO x purification rate.

本発明のハニカム担体は、セル隔壁表面にウォッシュコート法によって触媒コート層を形成することで、酸化触媒、三元触媒、NOx 吸蔵還元触媒、リーンNOx 触媒などとして利用することができる。またコートする材料を変更することで、HC吸着材、NOx 吸着材、H2S 吸着材などとして用いることもできる。 The honeycomb carrier of the present invention can be used as an oxidation catalyst, a three-way catalyst, a NO x storage reduction catalyst, a lean NO x catalyst, and the like by forming a catalyst coat layer on the cell partition wall surface by a wash coat method. Moreover, it can also be used as an HC adsorbent, NO x adsorbent, H 2 S adsorbent, etc. by changing the coating material.

1、3:ハニカム担体 2:波板 4:平板
10、30:セル通路 11、31:高セル密度部
12、32:低セル密度部
1, 3: Honeycomb carrier 2: Corrugated plate 4: Flat plate
10, 30: Cell passage 11, 31: High cell density part
12, 32: Low cell density part

Claims (6)

複数のセル通路をもつストレートフロー構造をなし内燃機関からの排ガスを浄化する排ガス浄化用触媒に用いられる排ガス浄化触媒用ハニカム担体であって、
排ガス流れ方向における下流側には、排ガス流れ方向に対して直角方向の断面における単位面積あたりの該セル通路の数であるセル密度が上流側より低密度の低セル密度部をもつことを特徴とする排ガス浄化触媒用ハニカム担体。
A honeycomb carrier for exhaust gas purification catalyst used for an exhaust gas purification catalyst that has a straight flow structure having a plurality of cell passages and purifies exhaust gas from an internal combustion engine,
The downstream side in the exhaust gas flow direction has a low cell density portion where the cell density, which is the number of the cell passages per unit area in the cross section perpendicular to the exhaust gas flow direction, is lower than the upstream side. A honeycomb carrier for exhaust gas purification catalyst.
前記低セル密度部は、下流側における全体断面積と該セル通路の断面積を上流側の全体断面積と該セル通路の断面積より大きくすることで形成されている請求項1に記載の排ガス浄化触媒用ハニカム担体。   2. The exhaust gas according to claim 1, wherein the low cell density portion is formed by making an overall cross-sectional area on the downstream side and a cross-sectional area of the cell passage larger than an overall cross-sectional area on the upstream side and a cross-sectional area of the cell passage. Honeycomb carrier for purification catalyst. 前記低セル密度部は、下流側において複数の該セル通路どうしを結合して該セル通路の数を上流側より少なくすることで形成されている請求項1に記載の排ガス浄化触媒用ハニカム担体。   The honeycomb carrier for an exhaust gas purification catalyst according to claim 1, wherein the low cell density portion is formed by connecting a plurality of the cell passages on the downstream side so that the number of the cell passages is smaller than that on the upstream side. 前記低セル密度部のセル密度は 300〜 499セル/in2 であり、前記低セル密度部以外の上流側におけるセル密度は 500〜 700セル/in2 である請求項1〜3のいずれかに記載の排ガス浄化触媒用ハニカム担体。 The cell density of the low cell density portion is 300 to 499 cells / in 2 , and the cell density on the upstream side other than the low cell density portion is 500 to 700 cells / in 2. A honeycomb carrier for an exhaust gas purification catalyst as described. 前記低セル密度部は、排ガス流出側端面からハニカム担体全長の20〜50%の範囲に形成されている請求項1〜4のいずれかに記載の排ガス浄化触媒用ハニカム担体。   The honeycomb carrier for an exhaust gas purification catalyst according to any one of claims 1 to 4, wherein the low cell density portion is formed in a range of 20 to 50% of the total length of the honeycomb carrier from an end surface on the exhaust gas outflow side. 金属製平板と金属製波板との積層体からなる請求項1〜5のいずれかに記載の排ガス浄化触媒用ハニカム担体。   The honeycomb carrier for an exhaust gas purification catalyst according to any one of claims 1 to 5, comprising a laminate of a metal flat plate and a metal corrugated plate.
JP2009140747A 2009-06-12 2009-06-12 Honeycomb support for exhaust gas purification catalyst Pending JP2010284599A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101453410B1 (en) 2012-11-20 2014-10-21 현대머티리얼 주식회사 Flow distribution adaptive type large catalyst filter
CN107848519A (en) * 2015-07-16 2018-03-27 克诺尔商用车制动系统有限公司 Silencer
WO2021079556A1 (en) * 2019-10-25 2021-04-29 日本碍子株式会社 Muffler and honeycomb structure for muffler

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101453410B1 (en) 2012-11-20 2014-10-21 현대머티리얼 주식회사 Flow distribution adaptive type large catalyst filter
CN107848519A (en) * 2015-07-16 2018-03-27 克诺尔商用车制动系统有限公司 Silencer
CN107848519B (en) * 2015-07-16 2020-05-19 克诺尔商用车制动系统有限公司 Noise silencer
WO2021079556A1 (en) * 2019-10-25 2021-04-29 日本碍子株式会社 Muffler and honeycomb structure for muffler

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