JPH04104838A - Waste gas purifying catalytic body - Google Patents
Waste gas purifying catalytic bodyInfo
- Publication number
- JPH04104838A JPH04104838A JP2223162A JP22316290A JPH04104838A JP H04104838 A JPH04104838 A JP H04104838A JP 2223162 A JP2223162 A JP 2223162A JP 22316290 A JP22316290 A JP 22316290A JP H04104838 A JPH04104838 A JP H04104838A
- Authority
- JP
- Japan
- Prior art keywords
- catalyst
- exhaust gas
- ceramic
- gas purification
- oxidation catalyst
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 230000003197 catalytic effect Effects 0.000 title abstract description 20
- 239000002912 waste gas Substances 0.000 title abstract 2
- 239000003054 catalyst Substances 0.000 claims abstract description 132
- 239000000919 ceramic Substances 0.000 claims abstract description 43
- 238000007254 oxidation reaction Methods 0.000 claims abstract description 37
- 230000003647 oxidation Effects 0.000 claims abstract description 35
- 239000000843 powder Substances 0.000 claims abstract description 32
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims abstract description 27
- 239000011230 binding agent Substances 0.000 claims abstract description 19
- 229910000510 noble metal Inorganic materials 0.000 claims abstract description 17
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims abstract description 16
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 14
- 229910052697 platinum Inorganic materials 0.000 claims abstract description 13
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 claims abstract description 10
- 239000000203 mixture Substances 0.000 claims abstract description 10
- 239000000377 silicon dioxide Substances 0.000 claims abstract description 7
- 229910052763 palladium Inorganic materials 0.000 claims abstract description 5
- 238000000746 purification Methods 0.000 claims description 32
- 239000002131 composite material Substances 0.000 claims description 19
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 claims description 10
- 229910052703 rhodium Inorganic materials 0.000 claims description 8
- 239000010948 rhodium Substances 0.000 claims description 8
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 claims description 8
- 239000002245 particle Substances 0.000 claims description 6
- 229910000420 cerium oxide Inorganic materials 0.000 claims description 3
- QVQLCTNNEUAWMS-UHFFFAOYSA-N barium oxide Chemical compound [Ba]=O QVQLCTNNEUAWMS-UHFFFAOYSA-N 0.000 claims description 2
- 229910001864 baryta Inorganic materials 0.000 claims description 2
- BMMGVYCKOGBVEV-UHFFFAOYSA-N oxo(oxoceriooxy)cerium Chemical compound [Ce]=O.O=[Ce]=O BMMGVYCKOGBVEV-UHFFFAOYSA-N 0.000 claims description 2
- 239000002923 metal particle Substances 0.000 abstract description 8
- 150000001875 compounds Chemical class 0.000 abstract 1
- 239000007789 gas Substances 0.000 description 51
- 239000010410 layer Substances 0.000 description 27
- 239000000463 material Substances 0.000 description 10
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 8
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical class [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 7
- 238000006243 chemical reaction Methods 0.000 description 5
- 229910052878 cordierite Inorganic materials 0.000 description 5
- JSKIRARMQDRGJZ-UHFFFAOYSA-N dimagnesium dioxido-bis[(1-oxido-3-oxo-2,4,6,8,9-pentaoxa-1,3-disila-5,7-dialuminabicyclo[3.3.1]nonan-7-yl)oxy]silane Chemical compound [Mg++].[Mg++].[O-][Si]([O-])(O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2)O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2 JSKIRARMQDRGJZ-UHFFFAOYSA-N 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- CPLXHLVBOLITMK-UHFFFAOYSA-N Magnesium oxide Chemical compound [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 4
- 229910002092 carbon dioxide Inorganic materials 0.000 description 4
- 239000001569 carbon dioxide Substances 0.000 description 4
- 229910002091 carbon monoxide Inorganic materials 0.000 description 4
- 229910002090 carbon oxide Inorganic materials 0.000 description 4
- 230000006866 deterioration Effects 0.000 description 4
- 230000005012 migration Effects 0.000 description 4
- 238000013508 migration Methods 0.000 description 4
- 239000000779 smoke Substances 0.000 description 4
- 238000002485 combustion reaction Methods 0.000 description 3
- 229930195733 hydrocarbon Natural products 0.000 description 3
- 150000002430 hydrocarbons Chemical class 0.000 description 3
- 239000011268 mixed slurry Substances 0.000 description 3
- 239000010970 precious metal Substances 0.000 description 3
- 238000005245 sintering Methods 0.000 description 3
- 239000007787 solid Substances 0.000 description 3
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 239000000470 constituent Substances 0.000 description 2
- 238000010411 cooking Methods 0.000 description 2
- 238000007598 dipping method Methods 0.000 description 2
- 239000010419 fine particle Substances 0.000 description 2
- 238000010304 firing Methods 0.000 description 2
- 238000004817 gas chromatography Methods 0.000 description 2
- 230000007774 longterm Effects 0.000 description 2
- 239000000395 magnesium oxide Substances 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- QQONPFPTGQHPMA-UHFFFAOYSA-N propylene Natural products CC=C QQONPFPTGQHPMA-UHFFFAOYSA-N 0.000 description 2
- 125000004805 propylene group Chemical group [H]C([H])([H])C([H])([*:1])C([H])([H])[*:2] 0.000 description 2
- 238000005507 spraying Methods 0.000 description 2
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000011247 coating layer Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000003292 glue Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- VUZPPFZMUPKLLV-UHFFFAOYSA-N methane;hydrate Chemical compound C.O VUZPPFZMUPKLLV-UHFFFAOYSA-N 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 239000001294 propane Substances 0.000 description 1
- 229910000077 silane Inorganic materials 0.000 description 1
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は、石油やガスなどを燃料とする各種燃焼機器、
自動車、ガスオーブン、オーブンレンジなどの調理器か
ら排出される油煙や未燃焼の炭化水素、−酸化炭素を完
全燃焼させ、炭酸ガスと水に分解する優れた触媒性能を
有する排ガス浄化触媒体に関する。[Detailed Description of the Invention] Industrial Application Field The present invention relates to various combustion equipment using oil, gas, etc. as fuel,
The present invention relates to an exhaust gas purification catalyst having excellent catalytic performance that completely burns oil smoke, unburned hydrocarbons, and carbon oxides discharged from cooking appliances such as automobiles, gas ovens, and oven ranges, and decomposes them into carbon dioxide gas and water.
従来の技術
従来、燃焼機器などから排出される油煙や未燃焼の炭化
水素、−酸化炭素を空気共存下で炭酸ガスと水蕉気に酸
化分解させる排ガス浄化触媒体としては、シリカ、アル
ミナなどのセラミック粉末を成形、焼成して得られるセ
ラミックハニカム構造体表面に、アルミナなどの微粉末
をコーティングし、さらにその上に白金、ロジウム、パ
ラジウムなどの貴金属からなる触媒を担持したものがあ
る。Conventional technology Conventionally, silica, alumina, etc. have been used as exhaust gas purification catalysts that oxidize and decompose oil smoke, unburned hydrocarbons, and carbon oxides emitted from combustion equipment into carbon dioxide and water shavings in the coexistence of air. There is a ceramic honeycomb structure obtained by molding and firing ceramic powder, the surface of which is coated with fine powder such as alumina, and a catalyst made of a noble metal such as platinum, rhodium, or palladium is supported on the surface.
この排ガス浄化触媒体に用いられているセラミックハニ
カム構造体は耐久性の観点からアルミナ、シリカ、マグ
２シアを主成分とするコーディエライトが主流である。The ceramic honeycomb structure used in this exhaust gas purification catalyst body is mainly made of cordierite whose main components are alumina, silica, and mag-2-shear from the viewpoint of durability.
このコーディエライトは高密度であるので表面積が小さ
く触媒の担体として適していない、したがって表面積を
大きくするためにコーディエライトの表面に表面積の大
きなアルミナなどの微粒子をコーティングし、その上に
触媒を担持するのが一般的である。Since this cordierite has a high density, its surface area is small and it is not suitable as a catalyst carrier. Therefore, in order to increase the surface area, the cordierite surface is coated with fine particles such as alumina with a large surface area, and the catalyst is placed on top of it. It is common to carry
また最近では触媒として貴金属の代わりにペロブスカイ
ト型複合酸化物を用いたものもあるが、これもセラミッ
クハニカム構造体の表面にペロブスカイト型複合酸化物
の触媒を無機質バインダーとともに担持した構成となっ
ている。Recently, there are also products that use perovskite-type composite oxides instead of noble metals as catalysts, but these also have a structure in which a perovskite-type composite oxide catalyst is supported on the surface of a ceramic honeycomb structure along with an inorganic binder.
発明が解決しようとする課題
しかしながら、酸化触媒としてペロブスカイト型複合酸
化物を用いた触媒体は高温下での触媒性能と耐久性に優
れているが、低温下での触媒性能が悪く、かつ白金など
の貴金属触媒に比べ粒子径が大きいので触媒として機能
する活性点の数が少ない。したがって排ガスの処理量が
多い場合には、排ガス浄化触媒体の寸法を大きくして触
媒体に対する負荷を小さくするか、または排ガス浄化触
媒体の温度を高くしないと十分な触媒性能が得られない
という課題があった。Problems to be Solved by the Invention However, although catalyst bodies using perovskite-type composite oxides as oxidation catalysts have excellent catalytic performance and durability at high temperatures, they have poor catalytic performance at low temperatures, and they do not contain metals such as platinum. Because the particle size is larger than that of noble metal catalysts, the number of active sites that function as a catalyst is small. Therefore, if a large amount of exhaust gas is to be processed, sufficient catalytic performance cannot be obtained unless the size of the exhaust gas purification catalyst is increased to reduce the load on the catalyst, or the temperature of the exhaust gas purification catalyst is increased. There was an issue.
一方、酸化触媒として白金などの貴金属触媒を表面積の
大きなアルミナなどの微粒子によるコーティング層上に
担持してなる触媒体は低温下での触媒性能に優れている
が、高温下では貴金属触媒の粒子がシンタリングや触媒
体表面から内部へのマイグレーションをおこし、触媒性
能が著しく劣化するという課題があった。On the other hand, a catalyst body in which a noble metal catalyst such as platinum is supported as an oxidation catalyst on a coating layer of fine particles such as alumina with a large surface area has excellent catalytic performance at low temperatures, but at high temperatures the particles of the noble metal catalyst There was a problem that sintering and migration from the surface of the catalyst body to the inside occurred, resulting in a significant deterioration of catalyst performance.
また貴金属触媒はコストが高く、資源的にも限りがある
ためこれに代わる触媒が強く要望されでいる。Furthermore, since noble metal catalysts are expensive and have limited resources, there is a strong demand for alternative catalysts.
そこで、本発明は排ガス浄化触媒体を構成する材料の種
類、構成および構造を改善することにより、上記課題と
なっている触媒性能を向上させ、かつ生産性に優れ、低
コストを実現できる排ガス浄化触媒体を提供することを
目的としている。Therefore, the present invention improves the type, composition, and structure of the materials constituting the exhaust gas purification catalyst, thereby improving the catalytic performance of the above-mentioned problem, and achieving exhaust gas purification with excellent productivity and low cost. The purpose is to provide a catalyst body.
課題を解決するための手段
上記目的を達成するために本発明の排ガス浄化触媒体は
、排ガスが通過する通気口を備えたアルミナ、ノリ力を
三成分とするセラミック構造体の表面に、セラミック微
粉末と酸化触媒と無機質バインダーとの混合物からなる
触媒層を設けたものである。Means for Solving the Problems In order to achieve the above objects, the exhaust gas purification catalyst body of the present invention has a ceramic structure having three components: alumina and glue, which is equipped with a vent through which exhaust gas passes, and has a ceramic microstructure. A catalyst layer made of a mixture of powder, an oxidation catalyst, and an inorganic binder is provided.
作用
したがって本発明によれば、セラミック構造体の表面に
セラミック微粉末と酸化触媒と無機質バインダーとの混
合物からなる触媒層を設けることによって排ガス浄化触
媒体は、触媒として機能する温度まで加熱され、加熱さ
れた排ガス浄化触媒体を通過する排ガス中の油煙、未燃
焼ガスおよび一酸化炭素は触媒表面に酸素とともに接触
し、酸化反応により炭酸ガスと水蒸気に変換される。Therefore, according to the present invention, by providing a catalyst layer made of a mixture of ceramic fine powder, an oxidation catalyst, and an inorganic binder on the surface of a ceramic structure, the exhaust gas purification catalyst body is heated to a temperature at which it functions as a catalyst. The oil smoke, unburned gas, and carbon monoxide in the exhaust gas that passes through the exhaust gas purification catalyst body come into contact with the catalyst surface together with oxygen, and are converted into carbon dioxide gas and water vapor by an oxidation reaction.
本発明のガス浄化触媒体に用いられる酸化触媒ペロブス
カイト型複合酸化物の微粉末と白金などの貴金属粒子か
ら構成される。この構成Ｇこおいて、低温下では白金な
どの貴金属触媒が排ガスの浄化に機能し、高温下ではペ
ロブスカイト型複合酸化物が排ガスの浄化に機能する。The oxidation catalyst used in the gas purification catalyst of the present invention is composed of fine powder of perovskite-type composite oxide and noble metal particles such as platinum. In this configuration G, a noble metal catalyst such as platinum functions to purify exhaust gas at low temperatures, and a perovskite type composite oxide functions to purify exhaust gas at high temperatures.
ペロブスカイト型複合酸化物は耐熱性に優れているので
触媒としての性能劣化がなく、貴金属触媒はそのほとん
どがセラミック微粉末とペロブスカイト型複合酸化物と
無機質バインダーの空隙に固定されているので、前述の
ノンタリングやマイグレーションが防止される。Perovskite-type composite oxides have excellent heat resistance, so there is no deterioration in their performance as catalysts, and most of the precious metal catalysts are fixed in the voids between the ceramic fine powder, perovskite-type composite oxides, and inorganic binder, so the above-mentioned Nontalling and migration are prevented.
また、本発明における排ガス浄化触媒体の触媒層はセラ
ミック微粉末を存在させているので酸化触媒の分散性が
向上し、触媒として機能する活性点の数が多くなってお
り、触媒性能が増大する。In addition, since the catalyst layer of the exhaust gas purification catalyst body in the present invention contains fine ceramic powder, the dispersibility of the oxidation catalyst is improved, and the number of active sites that function as a catalyst is increased, resulting in an increase in catalytic performance. .
実施例
以下、本発明の実施例を添付図面にもとづいて説明する
。第１図において、１は排ガス浄化触媒体の骨格となる
排ガスが通過する通気口６を有するセラミ、り構造体で
あり、このセラミック構造体１の表面に触媒層２か形成
される。この触媒層２は第２図に示すように、セラミッ
ク微粉末３と酸化触媒４と無機質バインダー５より構成
され、酸化触媒４はペロブスカイト型複合酸化物の微粉
末４ａと白金、パラジウムおよつｔ゛ロジウム少なくと
も１種の貴金属粒子４ｈとから構成されている。Embodiments Hereinafter, embodiments of the present invention will be described based on the accompanying drawings. In FIG. 1, reference numeral 1 denotes a ceramic structure having a vent 6 through which exhaust gas passes, serving as the skeleton of an exhaust gas purification catalyst, and a catalyst layer 2 is formed on the surface of this ceramic structure 1. As shown in FIG. 2, this catalyst layer 2 is composed of a fine ceramic powder 3, an oxidation catalyst 4, and an inorganic binder 5. It is composed of rhodium and at least one noble metal particle 4h.
そして触媒層２は以下の方法によって造られる。The catalyst layer 2 is manufactured by the following method.
まず、セラミック微粉末３と酸化触媒４と無ｌ！質バイ
ンダー５を十分に混合し、水を加えて適当な粘度に調整
した混合スラリーを作製する０次にこの混合スリラーを
スプレー、浸漬などの方法によりセラミック構造体１の
表面に付着させ、乾燥する。そしてこれを焼成すること
により触媒層２を得ることができる。First, ceramic fine powder 3, oxidation catalyst 4, and nothing! A mixed slurry is prepared by thoroughly mixing the binder 5 and adjusting the viscosity to an appropriate level by adding water.Next, this mixed slurry is applied to the surface of the ceramic structure 1 by spraying, dipping, etc., and dried. . Then, by firing this, the catalyst layer 2 can be obtained.
このとき酸化触媒４は触媒層２０表面だけでなく触媒層
２の内部にも存在するが、触媒層２がセラミンク微粉末
３、酸化触媒４中のペロブスカイト型複合酸化物の微粉
末４ａによって多孔質となっているので排ガスは触媒層
２の内部へも拡散可能となる。すなわち触媒層２はその
内部に存在する酸化触媒４も触媒として機能させること
ができるような構造となっている。At this time, the oxidation catalyst 4 exists not only on the surface of the catalyst layer 20 but also inside the catalyst layer 2, but the catalyst layer 2 is made porous by the ceramic fine powder 3 and the perovskite type composite oxide fine powder 4a in the oxidation catalyst 4. Therefore, the exhaust gas can also diffuse into the interior of the catalyst layer 2. That is, the catalyst layer 2 has a structure such that the oxidation catalyst 4 present therein can also function as a catalyst.
セラミ、り微粉末３と酸化触媒４の量は少なくなると触
媒性能が悪くなり、また多くなり過ぎると触媒層２の密
着性が悪くなる。前述の触媒性能と密着性を両立させる
ためには触媒層２の膜厚として１０〜２００μｍの範囲
が適している。また無機質バインダー５はセラミック構
造体１と触媒層２およびセラミック微粉末３と酸化触媒
４を接着する目的で用いるものであり、触媒性能の点か
らはできるだけ少ない方がよい、無機質バインダー５の
固形分の含有量はセラミック微粉末３と酸化触媒４の含
有量に対し、５〜１０重量％の範囲が通している。If the amounts of the ceramic powder 3 and the oxidation catalyst 4 are too small, the catalytic performance will be poor, and if they are too large, the adhesion of the catalyst layer 2 will be poor. In order to achieve both the above-described catalyst performance and adhesion, the thickness of the catalyst layer 2 is preferably in the range of 10 to 200 μm. In addition, the inorganic binder 5 is used for the purpose of bonding the ceramic structure 1 and the catalyst layer 2 and the ceramic fine powder 3 and the oxidation catalyst 4, and the solid content of the inorganic binder 5 is preferably as small as possible from the viewpoint of catalyst performance. The content ranges from 5 to 10% by weight based on the contents of the ceramic fine powder 3 and the oxidation catalyst 4.
セラミック微粉末３の材料としては、耐熱性、コストの
点からアルミナ、酸化セリウム、ジルコニアおよびバリ
タの少なくとも１種からなるものがよい。The material for the ceramic fine powder 3 is preferably one made of at least one of alumina, cerium oxide, zirconia, and baryta in terms of heat resistance and cost.
酸化触媒４の材料は広範囲の温度で優れた触媒性能を実
現するために、耐熱性と高温での触媒性能に優れ、低コ
ストであるペロブスカイト型複合酸化物と、低温での触
媒性能に優れた白金、パラジウムおよびロジウムの少な
（とも１種からなる貴金属粒子の組み合せで構成した方
がよい。In order to achieve excellent catalytic performance over a wide range of temperatures, the material for oxidation catalyst 4 is a perovskite-type composite oxide that has excellent heat resistance and catalytic performance at high temperatures and is low cost, and a perovskite-type composite oxide that has excellent catalytic performance at low temperatures. It is preferable to use a combination of noble metal particles containing only one type of platinum, palladium, and rhodium.
無機質バインダー５の材料は耐熱性の点からコロイド粒
子からなるシリカ、アルミナ、ジルコニア等がその目的
に適している。From the viewpoint of heat resistance, silica, alumina, zirconia, etc. made of colloidal particles are suitable as the material for the inorganic binder 5 for this purpose.
なお、排ガスが通過する通気口６の大きさは排ガスの流
量、圧［員、温度、排ガス浄化触媒体の大きさなど使用
条件によって異なるものであり、限定されるものではな
い。The size of the vent 6 through which the exhaust gas passes varies depending on usage conditions such as the flow rate, pressure, temperature, and size of the exhaust gas purification catalyst, and is not limited.
次に、本実施例の構成における作用を説明する。Next, the operation of the configuration of this embodiment will be explained.
排ガス浄化触媒体は自動車、燃焼機器、調理器などから
排出される未燃焼ガスや一酸化炭素を含む排ガス気流中
に配置され、触媒として機能する温度に加熱される。加
熱された排ガス浄化触媒体を通過する排ガス中の油煙、
炭化水素、−酸化炭素等は排ガス中の酸素とともに酸化
触媒４の表面に接触し、酸化反応により炭酸ガスと水蒸
気に変換され、通気口６より排出される。The exhaust gas purification catalyst body is placed in an exhaust gas stream containing unburned gas and carbon monoxide discharged from automobiles, combustion equipment, cooking appliances, etc., and is heated to a temperature at which it functions as a catalyst. Oil smoke in exhaust gas that passes through a heated exhaust gas purification catalyst body,
Hydrocarbons, carbon oxides, etc. come into contact with the surface of the oxidation catalyst 4 together with oxygen in the exhaust gas, are converted into carbon dioxide gas and water vapor by an oxidation reaction, and are discharged from the vent 6.
排ガス浄化触媒体に用いられる酸化触媒４はペロブスカ
イト型複合酸化物の微粉末４ａと、白金、パラ７″ウム
およびロジウムの少なくとも１１ａの貴金属粒子４ｂと
から構成されている。この構成において、低温下では低
温での触媒性能に優れている白金などの貴金属粒子４ｂ
が排ガスの浄化に機能し、高温下ではペロブスカイト型
複合酸化物４ａが排ガスの浄化に機能するので低温から
高温まで広範囲の温度領域において優れた触媒性能を実
現できる。The oxidation catalyst 4 used in the exhaust gas purification catalyst body is composed of fine powder 4a of perovskite-type composite oxide and noble metal particles 4b of at least 11a of platinum, para7'' and rhodium. Then, noble metal particles such as platinum 4b, which have excellent catalytic performance at low temperatures.
The perovskite type composite oxide 4a functions to purify exhaust gas at high temperatures, so excellent catalytic performance can be achieved in a wide temperature range from low to high temperatures.
触媒層２に存在する酸化触媒４は触媒層２の外表面だけ
でなく、触媒層２の内部にも存在しており、触媒層２が
前述したように多孔質となっているため排ガスがその内
部へも拡散し、表面だけでなく内部に存在する酸化触媒
４も触媒として機能することができるとともに、セラミ
ノーり微粉末３を用いることにより酸化触媒４の分散性
を高くすることができる。その結果、本発明の排ガス浄
化触媒体は触媒として機能する表面積を大きく、かつ触
媒として機能する活性壱の数を多くすることができ、よ
り優れた触媒性能を実現することができるのである。The oxidation catalyst 4 present in the catalyst layer 2 exists not only on the outer surface of the catalyst layer 2 but also inside the catalyst layer 2, and as the catalyst layer 2 is porous as described above, exhaust gas is The oxidation catalyst 4 that diffuses into the interior and exists not only on the surface but also inside can function as a catalyst, and by using the ceraminol fine powder 3, the dispersibility of the oxidation catalyst 4 can be increased. As a result, the exhaust gas purification catalyst body of the present invention can have a large surface area that functions as a catalyst, and can increase the number of active catalysts that function as a catalyst, thereby achieving better catalytic performance.
ペロブスカイト型複合酸化物４ａは高温下でもその結晶
構造が安定しているので触媒としての機能が維持され、
白金、パラ、−ラム、ロジウムなどの貴金属粒子４ｂは
そのほとんどがセラミック微粉末３とペロブスカイト型
複合酸化物４ａと無機質バインダー５の空隙に固定され
ているので前述したシンタリングやマイグレーシランが
防止され、その結果、長期の使用において触媒性能の劣
化を防止できる。Since the perovskite-type composite oxide 4a has a stable crystal structure even at high temperatures, it maintains its function as a catalyst.
Most of the noble metal particles 4b such as platinum, para, rhum, and rhodium are fixed in the voids between the ceramic fine powder 3, the perovskite composite oxide 4a, and the inorganic binder 5, so that the above-mentioned sintering and migration silane are prevented. As a result, deterioration of catalyst performance can be prevented during long-term use.
次に本発明の具体的実験例について述べる。Next, specific experimental examples of the present invention will be described.
実験例１
第１図、第２図に示した構成および前述の製造方法を用
いて排ガス浄化触媒体を作製した。この排ガス浄化触媒
体の作製に適用した材料、組成、形状などの各仕様は以
下の通りである。Experimental Example 1 An exhaust gas purification catalyst body was manufactured using the configuration shown in FIGS. 1 and 2 and the manufacturing method described above. The specifications of the materials, composition, shape, etc. applied to the production of this exhaust gas purification catalyst body are as follows.
（１）ハニカム状のセラミック構造体１■材料
・アルミナ、シリカ、マグネシアを主成分とするコーデ
ィエライト
■通気口６の数
・２００個／１ｎｃｈ”
（２）触媒層２の構成材料および組成
■セラミック微粉末３
・Ｔ−アルミナ ７５重量％■酸化触媒４
・ペロブスカイト型複合酸化物４ａ
Ｌａ、。ｑ Ｃｅｅ、 （Ｃｏｏｓ １８．５重
量％・貴金属粒子４ｂ
パラジウム １．５重量％■無機質バイン
ダー５
・アルミナゾル（固形分） ５重量％このように作製
した排ガス浄化触媒体について、固定流通式で一酸化炭
素０．１％濃度（空気バランス）およびプロパン０．１
％濃度（空気バランス）の２種類のガスを用い、空間速
度１５０００ｈｒ−’の条件下でガスクロマトグラフィ
により変換率（浄化率）を評価したところ、−酸化炭素
は１５０°Ｃで９０％以上、プロパンは３５０°Ｃで９
０％以上の変換率が得られた。(1) Honeycomb-shaped ceramic structure 1 ■Material: Cordierite whose main components are alumina, silica, and magnesia ■Number of vents 6: 200 pieces/1 nch" (2) Constituent materials and composition of catalyst layer 2■ Ceramic fine powder 3 ・T-alumina 75% by weight ■Oxidation catalyst 4 ・Perovskite type composite oxide 4a La,. Alumina sol (solid content) 5% by weight Regarding the exhaust gas purification catalyst body prepared in this way, carbon monoxide concentration of 0.1% (air balance) and propane concentration of 0.1% were obtained using a fixed flow system.
When the conversion rate (purification rate) was evaluated by gas chromatography under the condition of space velocity 15,000 hr-' using two types of gases with a concentration of is 9 at 350°C
A conversion rate of more than 0% was obtained.
また、セラミック微粉末３のＴ−アルミナの代わりにジ
ルコニアとバリダの混合微粉末を用いたところ、上記と
ほぼ同様な結果を得た。Furthermore, when a mixed fine powder of zirconia and barida was used instead of T-alumina in the ceramic fine powder 3, almost the same results as above were obtained.
実験例２
第１図、第２図に示した構成および前記製造方法を用い
て排ガス浄化触媒体を作製した。この排ガス浄化触媒体
の作製に適用した材料、組成、形状などの各仕様は以下
の通りである。Experimental Example 2 An exhaust gas purification catalyst body was manufactured using the configuration shown in FIGS. 1 and 2 and the manufacturing method described above. The specifications of the materials, composition, shape, etc. applied to the production of this exhaust gas purification catalyst body are as follows.
（１）ハニカム状のセラミック構造体１■材料
・アルミナ、シリカ、マグネシアを主成分とするコーデ
ィエライト
■通気口６の数
２００個／１ｎｃｈ”
（２）触媒層２の構成材料および組成
■セラミック微粉末３
・酸化セリウム ５０重量％■酸化触媒４
・ペロブスカイト型複合酸化物４ａ
Ｌａｏ、 ＊ Ｓｒｏ、 ｔ Ｃｏｏ、 ｑ Ｍｎｏ、
ｌ Ｏｓ４４重量％
・貴金属粒子４ｂ
白金 １．０重量％■無機質バイ
ンダー５
・ジルコニアゾル（固形分） ５重量％このように作製
した排ガス浄化触媒体について、固定流通式で一酸化炭
素０．１％濃度（空気バランス）およびプロピレン０．
１％濃度（空気バランス）の２種類のガスを用い、空間
速度１５０００ｈｒ−’の条件下でガスクロマトグラフ
ィにより変換率（浄化率）を評価したところ、−酸化炭
素は１８０°Ｃで９０％以上、プロピレンは４００°Ｃ
で９０％以上の変換率が得られた。(1) Honeycomb-shaped ceramic structure 1 ■Material Cordierite whose main components are alumina, silica, and magnesia ■Number of vents 6: 200/1 nch" (2) Constituent materials and composition of catalyst layer 2 ■Ceramic Fine powder 3 - Cerium oxide 50% by weight ■ Oxidation catalyst 4 - Perovskite type composite oxide 4a Lao, * Sro, t Coo, q Mno,
l Os 44% by weight ・Precious metal particles 4b Platinum 1.0% by weight ■Inorganic binder 5 ・Zirconia sol (solid content) 5% by weight Regarding the exhaust gas purification catalyst body prepared in this way, carbon monoxide 0.1% in a fixed flow type. Concentration (air balance) and propylene 0.
When the conversion rate (purification rate) was evaluated by gas chromatography using two types of gases with a concentration of 1% (air balance) and a space velocity of 15,000 hr-', -carbon oxide was more than 90% at 180°C, Propylene is 400°C
A conversion rate of over 90% was obtained.
また、貴金属として白金の代わりにロジウムを用いたと
ころ、上記とほぼ同様な結果を得た。Furthermore, when rhodium was used instead of platinum as the noble metal, almost the same results as above were obtained.
このように上記実施例によれば、セラミック微粉末３と
ペロブスカイト型複合酸化物４ａおよび貴金属粒子４ｂ
からなる酸化触媒４を無機質バインダー５とともにセラ
ミック構造体ｌの表面に設けているため極めて高い変換
率が得られるという効果が得られた。Thus, according to the above embodiment, the ceramic fine powder 3, the perovskite type composite oxide 4a, and the noble metal particles 4b
Since the oxidation catalyst 4 consisting of the following was provided on the surface of the ceramic structure 1 together with the inorganic binder 5, an extremely high conversion rate was obtained.
発明の効果
ｌ実施例より明らかなように本発明の排ガス浄化触媒体
は、排ガス浄化触媒体を構成するセラミック構造体の表
面にセラミック微粉末と酸化触媒と無機質バインダーと
の混合物よりなる触媒層を形成したことにより、高温下
においても低温から高温まで酸化触媒が広範囲の温度領
域において排ガスの浄化に機能し、優れた触媒性能を発
揮することができる。Effects of the Invention As is clear from the examples, the exhaust gas purification catalyst of the present invention has a catalyst layer made of a mixture of fine ceramic powder, an oxidation catalyst, and an inorganic binder on the surface of the ceramic structure constituting the exhaust gas purification catalyst. Due to this formation, the oxidation catalyst functions to purify exhaust gas in a wide temperature range from low to high temperatures even at high temperatures, and can exhibit excellent catalytic performance.
また触媒層は排ガスがその内部へ拡散できるように多孔
質構造となっているので、触媒層表面だけでなく内部に
存在する酸化触媒も触媒として機能することができると
ともに、セラミック微粉末を用いることにより酸化触媒
の分散性を高くすることができるので触媒として機能す
る表面積を大きく、かつ触媒として機能する活性点の数
を多くすることができる。その結果、より優れた触媒性
能を実現することができる。In addition, since the catalyst layer has a porous structure so that exhaust gas can diffuse into the inside, not only the oxidation catalyst present on the surface of the catalyst layer but also the oxidation catalyst inside can function as a catalyst, and it is possible to use fine ceramic powder. Since the dispersibility of the oxidation catalyst can be increased, the surface area that functions as a catalyst can be increased, and the number of active sites that can function as a catalyst can be increased. As a result, better catalyst performance can be achieved.
さらに酸化触媒として用いるペロブスカイト型複合酸化
物は耐熱性に優れているので高温化で使用されても触媒
としての性能劣化を防止することができ、一方、白金、
パラジウム、ロジウムなどの貴金属粒子はそのほとんど
がセラミック微粉末とペロブスカイト型複合酸化物と無
機質バインダーの空隙に固定されているのでシンタリン
グやマイグレーションを防止することができる。その結
果、長期の使用において優れた触媒性能を維持できる。Furthermore, the perovskite-type composite oxide used as an oxidation catalyst has excellent heat resistance, so it can prevent performance deterioration as a catalyst even when used at high temperatures.On the other hand, platinum,
Most of the precious metal particles such as palladium and rhodium are fixed in the voids between the ceramic fine powder, the perovskite complex oxide, and the inorganic binder, so sintering and migration can be prevented. As a result, excellent catalytic performance can be maintained during long-term use.
なお、触媒層はセラミック微粉末と酸化触媒と無機質バ
インダーからなる混合スラリーをスプレーまたは浸漬な
どの方法によってセラミック構造体の表面に付着させる
ことにより形成されるので簡単な製造工程で生産できる
ものである。The catalyst layer is formed by attaching a mixed slurry consisting of fine ceramic powder, an oxidation catalyst, and an inorganic binder to the surface of the ceramic structure by spraying or dipping, so it can be produced through a simple manufacturing process. .
第１図は本発明の一実施例である排ガス浄化触媒体の要
部拡大断面図、第２図は触媒層の要部拡大断面図である
。
１・・・・・・セラミック構造体、２・・・・・・触媒
層、３・・・・・・セラミンク微粉末、４・・・・・・
酸化触媒、５・・・・・・無機質バインダー、６・・・
・・・通気口。FIG. 1 is an enlarged sectional view of a main part of an exhaust gas purification catalyst body according to an embodiment of the present invention, and FIG. 2 is an enlarged sectional view of a main part of a catalyst layer. 1...Ceramic structure, 2...Catalyst layer, 3...Ceramink fine powder, 4...
Oxidation catalyst, 5... Inorganic binder, 6...
···vent.
Claims (3)
カを主成分とするセラミック構造体の表面に、セラミッ
ク微粉末と酸化触媒と無機質バインダーとの混合物より
なる触媒層を形成した排ガス浄化触媒体。(1) Exhaust gas purification catalyst body in which a catalyst layer made of a mixture of fine ceramic powder, oxidation catalyst, and inorganic binder is formed on the surface of a ceramic structure mainly composed of alumina and silica, which is equipped with vents through which exhaust gas passes. .
ブスカイト型複合酸化物と、白金、パラジウムおよびロ
ジウムの少なくとも１種の貴金属粒子とからなる請求項
１記載の排ガス浄化触媒体。(2) The exhaust gas purification catalyst body according to claim 1, wherein the oxidation catalyst comprises a perovskite-type composite oxide represented by the basic structural formula ABO_3 and particles of at least one noble metal selected from platinum, palladium, and rhodium.
ルコニア、およびバリタの少なくとも１種からなる請求
項１記載の排ガス浄化触媒体。(3) The exhaust gas purification catalyst body according to claim 1, wherein the ceramic fine powder comprises at least one of alumina, cerium oxide, zirconia, and baryta.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2223162A JPH04104838A (en) | 1990-08-23 | 1990-08-23 | Waste gas purifying catalytic body |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2223162A JPH04104838A (en) | 1990-08-23 | 1990-08-23 | Waste gas purifying catalytic body |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04104838A true JPH04104838A (en) | 1992-04-07 |
Family
ID=16793769
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2223162A Pending JPH04104838A (en) | 1990-08-23 | 1990-08-23 | Waste gas purifying catalytic body |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04104838A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH1076159A (en) * | 1996-09-03 | 1998-03-24 | Hino Motors Ltd | Exhaust gas purification catalyst and its production |
| JPH10156181A (en) * | 1996-10-02 | 1998-06-16 | Hino Motors Ltd | Exhaust gas purification catalyst |
| JP2009195797A (en) * | 2008-02-20 | 2009-09-03 | Mitsubishi Motors Corp | Exhaust-cleaning device for internal combustion engine |
-
1990
- 1990-08-23 JP JP2223162A patent/JPH04104838A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH1076159A (en) * | 1996-09-03 | 1998-03-24 | Hino Motors Ltd | Exhaust gas purification catalyst and its production |
| JPH10156181A (en) * | 1996-10-02 | 1998-06-16 | Hino Motors Ltd | Exhaust gas purification catalyst |
| JP2009195797A (en) * | 2008-02-20 | 2009-09-03 | Mitsubishi Motors Corp | Exhaust-cleaning device for internal combustion engine |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6221804B1 (en) | Catalyst for purifying exhaust gas and manufacturing method thereof | |
| JP3953630B2 (en) | Automobile exhaust catalyst and its production method | |
| US5057482A (en) | Catalytic composite for purifying exhaust gases and a method for preparing the same | |
| JPH03161052A (en) | Exhaust gas cleaning catalyst and its preparation | |
| JP2002361083A (en) | Exhaust gas cleaning catalyst for internal combustion engine, method of producing the same and claening apparatus | |
| CN112808279A (en) | Catalyst for exhaust gas purification | |
| JPH11276907A (en) | Catalyst for purifying exhaust gas and its production | |
| JPH04104838A (en) | Waste gas purifying catalytic body | |
| JPH04145946A (en) | Catalyst for purification of exhaust gas | |
| JPH04122455A (en) | Exhaust gas purification catalyst body | |
| JPH03296438A (en) | Catalyst for waste gas purification | |
| JPH11244695A (en) | Oxidation catalyst | |
| JPH04110045A (en) | Catalyst body for purification of exhaust gas and its production | |
| JPH0435745A (en) | Catalytic body for purification of exhaust gas | |
| JPH02119939A (en) | Exhaust gas purification catalyst | |
| WO2023047185A1 (en) | Exhaust gas purification catalyst, and exhaust gas purification catalyst device for vehicles | |
| JPH05309272A (en) | Production of oxidation catalyst | |
| JPS6260937B2 (en) | ||
| JP2012086187A (en) | Catalyst material, and method for manufacturing the same | |
| JP2760439B2 (en) | Exhaust gas purification catalyst body and method for producing the same | |
| JPH02164456A (en) | Gas purifying material | |
| JPH05329366A (en) | Manufacture of oxidation catalyst | |
| JPH03157140A (en) | Catalyst for purifying exhaust gas and its production | |
| JPH0275348A (en) | Exhaust gas purifying catalyst | |
| JPH02164455A (en) | Exhaust gas purifying catalyst |