JPH0714481B2 - Exhaust gas purification catalyst - Google Patents
Exhaust gas purification catalystInfo
- Publication number
- JPH0714481B2 JPH0714481B2 JP62186145A JP18614587A JPH0714481B2 JP H0714481 B2 JPH0714481 B2 JP H0714481B2 JP 62186145 A JP62186145 A JP 62186145A JP 18614587 A JP18614587 A JP 18614587A JP H0714481 B2 JPH0714481 B2 JP H0714481B2
- Authority
- JP
- Japan
- Prior art keywords
- exhaust gas
- catalyst
- nox
- gas purification
- purification 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.)
- Expired - Lifetime
Links
- 239000003054 catalyst Substances 0.000 title claims description 19
- 238000000746 purification Methods 0.000 title claims 2
- 238000000354 decomposition reaction Methods 0.000 claims description 5
- 229910052763 palladium Inorganic materials 0.000 claims description 4
- 229910052697 platinum Inorganic materials 0.000 claims description 4
- 238000002485 combustion reaction Methods 0.000 claims description 2
- 239000013078 crystal Substances 0.000 claims description 2
- 239000003779 heat-resistant material Substances 0.000 claims description 2
- 239000011230 binding agent Substances 0.000 claims 1
- 239000002131 composite material Substances 0.000 claims 1
- 239000008188 pellet Substances 0.000 claims 1
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 43
- 239000007789 gas Substances 0.000 description 10
- 239000001301 oxygen Substances 0.000 description 10
- 229910052760 oxygen Inorganic materials 0.000 description 10
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 9
- KDLHZDBZIXYQEI-UHFFFAOYSA-N palladium Substances [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 7
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Substances [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 6
- 239000003638 chemical reducing agent Substances 0.000 description 5
- 239000010949 copper Substances 0.000 description 5
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 229930195733 hydrocarbon Natural products 0.000 description 3
- 150000002430 hydrocarbons Chemical class 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical compound [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 description 2
- QPLDLSVMHZLSFG-UHFFFAOYSA-N Copper oxide Chemical compound [Cu]=O QPLDLSVMHZLSFG-UHFFFAOYSA-N 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- 229910021529 ammonia Inorganic materials 0.000 description 2
- AYJRCSIUFZENHW-UHFFFAOYSA-L barium carbonate Chemical compound [Ba+2].[O-]C([O-])=O AYJRCSIUFZENHW-UHFFFAOYSA-L 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 229910052878 cordierite Inorganic materials 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 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 2
- 238000010304 firing Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- SIWVEOZUMHYXCS-UHFFFAOYSA-N oxo(oxoyttriooxy)yttrium Chemical compound O=[Y]O[Y]=O SIWVEOZUMHYXCS-UHFFFAOYSA-N 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910052688 Gadolinium Inorganic materials 0.000 description 1
- 206010021143 Hypoxia Diseases 0.000 description 1
- 229910001361 White metal Inorganic materials 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 235000019270 ammonium chloride Nutrition 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 229960004643 cupric oxide Drugs 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 239000004570 mortar (masonry) Substances 0.000 description 1
- 150000002926 oxygen Chemical class 0.000 description 1
- PIBWKRNGBLPSSY-UHFFFAOYSA-L palladium(II) chloride Chemical compound Cl[Pd]Cl PIBWKRNGBLPSSY-UHFFFAOYSA-L 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 210000002345 respiratory system Anatomy 0.000 description 1
- 230000002000 scavenging effect Effects 0.000 description 1
- 239000010969 white metal Substances 0.000 description 1
- 229910052727 yttrium Inorganic materials 0.000 description 1
Landscapes
- Exhaust Gas Treatment By Means Of Catalyst (AREA)
- Catalysts (AREA)
Description
【発明の詳細な説明】 産業上の利用分野 本発明は各種自動車、各種工業用炉の燃焼器から排出さ
れる窒素酸化物（NOx）を分解し、無害なN2に変換する
触媒に関するものである。TECHNICAL FIELD The present invention relates to a catalyst that decomposes nitrogen oxides (NOx) emitted from combustors of various automobiles and various industrial furnaces and converts them into harmless N 2. is there.
従来の技術 一般に各種自動車及び各種工業炉からの排出ガスには多
量のNO,NO2で代表される窒素酸化物（NOx）が含まれて
いる。これらのNOxは光化学スモッグの原因とされてい
る許りでなく、人体にとって呼吸気系に障害を起すとい
われている。特にNO2については排出規準が定められて
いる。これらNOxを無害なN2にまで還元するプロセスに
ついては、（１）排気ガス中に酸素の量が少ない場合は
CO各種炭化水素（HC）等の還元剤を用いてCOをCO2にNO
をN2にする、いわゆる三元触媒方式が自動車の排気ガス
対策として確立されている。（２）一方、排気ガス中に
多量の酸素が含まれている場合、アンモニアを還元剤と
して用いるプロセスが工業的に確立されている。しかし
ながら、最近、自動車において、燃費を高めるため、空
気リッチのいわゆるリーン燃焼についての要望が高くな
ってきているが、この領域では、従来の三元触媒はNOの
分解には効果がないという問題がある。この為、自動車
業界では従来から各種還元剤を用いずに直接分解する方
式について、強く望まれているが、実用レベルでは確立
されていない。2. Description of the Related Art Generally, exhaust gas from various automobiles and various industrial furnaces contains a large amount of nitrogen oxides (NOx) represented by NO and NO 2 . These NOx are not the cause of photochemical smog and are said to cause damage to the respiratory system for the human body. Especially for NO 2 , emission standards have been established. Regarding the process of reducing these NOx to harmless N 2 , (1) When the amount of oxygen in the exhaust gas is small,
CO CO to CO 2 using reducing agents such as various hydrocarbons (HC) NO
A so-called three-way catalyst system that changes N 2 to N 2 has been established as a vehicle exhaust gas countermeasure. (2) On the other hand, when the exhaust gas contains a large amount of oxygen, a process using ammonia as a reducing agent has been industrially established. However, recently, in automobiles, there is an increasing demand for so-called lean combustion in which air is rich in order to improve fuel economy, but in this area, there is a problem that conventional three-way catalysts are not effective in decomposing NO. is there. Therefore, in the automobile industry, a method of directly decomposing without using various reducing agents has been strongly desired, but it has not been established at a practical level.
発明が解決しようとする問題点 我々は排気ガス中に多量の酸素が含まれる場合の窒素酸
化物（NOx）を各種還元剤を用いずに直接N2とO2（一部N
2Ｏを含む）に分解する触媒を開発しようとするもので
ある。INVENTION Problems to be Solved point we direct the nitrogen oxides if they contain a large amount of oxygen in the exhaust gas (NOx) without the use of a variety of reducing agents N 2 and O 2 (part N
It is intended to develop a catalyst that decomposes into (including 2 O).
問題点を解決するための手段 この問題点を解決するために本発明は、結晶構造式Ba2B
1Cu3O7−δ（ＢはＹまたGd）で構成したペロブスカイト
型構造を有する複合酸化物にPtまたはPdの少なくともい
ずれか一方を0.1〜1.0％担持する構成としたNOx分解触
媒を内然機関を有する車の排ガス通路中に設置する構成
とした。Means for Solving the Problems In order to solve this problem, the present invention provides a crystalline structural formula Ba 2 B.
A NOx decomposing catalyst having 0.1% to 1.0% of Pt or Pd supported on a complex oxide having a perovskite structure composed of 1 Cu 3 O 7 −δ (B is Y or Gd) It is configured to be installed in the exhaust gas passage of a car having an engine.
作用 各種無機耐熱材料に担持した複合酸化物を構成する元素
の内、銅にはその表面にNOxが吸着しやすい。さらに今
回我々の開発したBa−Ｙ−Cu系の化合物は極低温では超
伝導物質として注目されているように電子がCu−Ｏ−Cu
を通して非常に流れやすく、又吸着したNOにも電子が流
れ込みやすい。即ち、我々の赤外吸収（IR）によるNO吸
着状態の分析結果ではNO の状態で吸着していた。NOは
よく知られているように反結合性軌道に１ケ電子が存在
し、NO となることにより結合力が弱まる。この結果、
ＮとＯの結合距離は長くなり、このＯδ−と電子が一部
抜けた後の格子酸素Ｏδ＋とが反応する。この結果NOx
はN2とO2（一部N2Ｏも含む）に分解する。格子酸素の抜
けた後には気相の酸素が入っている。この時一部添加し
た白金族は酸素捕捉力が強く、この酸素がBa−Ｙ−Cuの
化合物の酸素欠陥を埋める。このようにして触媒作用の
サイクルは完結する。Action Elements that make up complex oxides supported on various inorganic heat-resistant materials
Of these, NOx is easily adsorbed on the surface of copper. More now
The Ba-Y-Cu compound we have developed is extremely cold at extremely low temperatures.
As attracting attention as a conductive material, electrons are Cu-O-Cu
It is very easy to flow through, and electrons also flow to the adsorbed NO.
Easy to slip in. That is, the NO absorption due to our infrared absorption (IR)
NO in the analysis result of the wearing condition It was adsorbed in the state of. NO is
As is well known, there is one electron in the antibonding orbit.
And NO The binding force is weakened by becoming. As a result,
The bond distance between N and O becomes long, and this Oδ−And some electronic
Lattice oxygen O after escapeδ +And react. This result NOx
Is N2And O2(Part N2(Including O). Depletion of lattice oxygen
After injuring, there is gas phase oxygen. At this time, add some
The platinum group has a strong oxygen scavenging power, and this oxygen is the Ba-Y-Cu
Fill the oxygen deficiency of the compound. In this way
The cycle is complete.
実施例 以下実施例について述べる。Examples Examples will be described below.
実施例（１）酸化第２銅、酸化イットリウム、炭酸バリ
ウムをモル比にして3:1:2になるように調製した混合物
を乳鉢でよく混合した後800℃で５時間仮焼した。仮焼
後、サンプルをさらに粉砕、混合しプレスで成型し、92
0℃で10時間空気中で焼成した。焼成後Ｘ線回折による
測定の結果、超伝導で報告されているBa2YCu3O7−δの
結晶構造を有していた。このサンプルに塩化バラジウム
アンモニウム錯体溶液によりPdを0.2％担持した。この
サンプルを水、コロイダルアルミナと共にスラリー化
し、400cell/inch2のコーディライトハニカムに担持しN
Ox分解触媒とした。Example (1) A mixture prepared by mixing cupric oxide, yttrium oxide, and barium carbonate in a molar ratio of 3: 1: 2 was thoroughly mixed in a mortar and then calcined at 800 ° C. for 5 hours. After calcination, the sample is further crushed, mixed and molded by pressing,
Baking in air at 0 ° C. for 10 hours. As a result of measurement by X-ray diffraction after firing, it had the crystal structure of Ba 2 YCu 3 O 7 −δ reported in superconductivity. 0.2% of Pd was supported on this sample by the ammonium chloride complex solution. This sample was slurried with water and colloidal alumina, and loaded on a 400 cell / inch2 cordierite honeycomb.
It was used as an Ox decomposition catalyst.
上記触媒を自動車に適用した例を述べる。第１図は自動
車の構成図である。エンジン１より排出されたガスは、
酸化触媒２を通過することにより、未然の炭化水素（H
C）はCO2と水に、又COはCO2に変化する。この後、前
記、NOx分解触媒３を通過することによりNOxはN2とO
2（一部N2Ｏを含む）に分解する。その後、クリーンに
なったガスは排気口４より系外に放出される。この時NO
x分解触媒の温度は320℃でありNOxの低減率は50％であ
った。An example in which the above catalyst is applied to an automobile will be described. FIG. 1 is a block diagram of an automobile. The gas discharged from the engine 1 is
By passing through the oxidation catalyst 2, hydrocarbons (H
C) changes to CO 2 and water, and CO changes to CO 2 . After that, NOx is converted to N 2 and O by passing through the NOx decomposition catalyst 3.
Decomposes into 2 (including some N 2 O). After that, the cleaned gas is discharged to the outside of the system through the exhaust port 4. NO at this time
The temperature of the x decomposition catalyst was 320 ° C, and the NOx reduction rate was 50%.
実施例（２） 実施例（１）の酸化イットリウムのかわ
りに酸化ガドリウムを用い、モル比にしてBa:Gd:Cu:2:
1:3になるように調整し、実施例（１）と同様に焼成
後、塩化パラジウムアンミン錯体溶液よりPd0.2％担持
した。このサンプルを実施例（１）と同様にコーディエ
ライトハニカムに担持し、第１図の自動車に適用した。
この時のNOxの低減率は40％であった。なお上記実施例
（１）および（２）記載の白金属例としてパラジウムを
用いた例を示したが白金あるいは白金およびパラジウム
混合物を用いても同様の効果が得られた。Example (2) Gadtrium oxide was used in place of the yttrium oxide of Example (1), and the molar ratio was Ba: Gd: Cu: 2 :.
It was adjusted to be 1: 3, and after firing in the same manner as in Example (1), 0.2% of Pd was loaded from the palladium chloride ammine complex solution. This sample was loaded on a cordierite honeycomb in the same manner as in Example (1) and applied to the automobile shown in FIG.
The NOx reduction rate at this time was 40%. It should be noted that although an example using palladium was shown as an example of the white metal described in Examples (1) and (2) above, the same effect was obtained using platinum or a mixture of platinum and palladium.
発明の効果 本発明の効果は以下のとおりである。Effects of the Invention The effects of the present invention are as follows.
１） 従来のアンモニア、CO等のように還元剤を用いな
くともNOxを分解することが出来る。1) NOx can be decomposed without using a reducing agent like conventional ammonia and CO.
２） 酸素が10％前後、NOxがppmオーダという酸素大過
剰でもNOxを分離することが出来る。2) NOx can be separated even with a large excess of oxygen, where oxygen is around 10% and NOx is on the order of ppm.
３） 反応温度が300℃程度と非常にゆるやかな条件で
あり広い範囲に適用できる。3) The reaction temperature is about 300 ° C, which is a very mild condition and can be applied to a wide range.
４） 触媒粉末自体920℃という高温で処理してあり耐
熱性が高い。4) The catalyst powder itself has been treated at a high temperature of 920 ° C and has high heat resistance.
以上の効果の結果、各種燃焼器（家庭用燃焼器、工業用
炉等）から排出されるNOxの分解に効果的である。As a result of the above effects, it is effective in decomposing NOx discharged from various combustors (household combustors, industrial furnaces, etc.).
図は本発明の一実施例における排ガス浄化用触媒を用い
た自動車の構成図である。 １……エンジン、２……酸化触媒、３……NOx分解触
媒、４……排気孔。FIG. 1 is a configuration diagram of an automobile using an exhaust gas purifying catalyst according to an embodiment of the present invention. 1 ... Engine, 2 ... Oxidation catalyst, 3 ... NOx decomposition catalyst, 4 ... Exhaust hole.
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 昭64−30647（ＪＰ，Ａ) 特開 昭64−30642（ＪＰ，Ａ) 特開 昭64−30643（ＪＰ，Ａ) 特開 昭64−30648（ＪＰ，Ａ) 特開 昭64−30644（ＪＰ，Ａ) 特開 昭64−30649（ＪＰ，Ａ) 特開 昭64−30645（ＪＰ，Ａ) ─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP-A-64-30647 (JP, A) JP-A-64-30642 (JP, A) JP-A-64-30643 (JP, A) JP-A-64- 30648 (JP, A) JP 64-30644 (JP, A) JP 64-30649 (JP, A) JP 64-30645 (JP, A)
Claims (2)
d）で構成したペロブスカイト型構造を有する複合酸化
物にPtまたはPdの少なくともいずれか一方を0.1〜1.0％
担持する構成としたNOx分解触媒を内燃機関を有する車
の排ガス通路中に設置する排ガス浄化用触媒。1. A crystal structural formula Ba 2 B 1 Cu 3 O 7 −δ (B is Y or G
0.1 to 1.0% of at least one of Pt and Pd is added to the complex oxide having a perovskite structure formed in d).
An exhaust gas purification catalyst in which a NOx decomposition catalyst configured to be supported is installed in the exhaust gas passage of a vehicle having an internal combustion engine.
ム状に成形した触媒担体の表面に複合酸化物を無機バイ
ンダと共に担持する構成とした特許請求の範囲第１項記
載の排ガス浄化用触媒。2. The exhaust gas purifying catalyst according to claim 1, wherein the composite oxide is carried together with an inorganic binder on the surface of a catalyst carrier formed of an inorganic heat-resistant material in the form of pellets or a honeycomb.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62186145A JPH0714481B2 (en) | 1987-07-24 | 1987-07-24 | Exhaust gas purification catalyst |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62186145A JPH0714481B2 (en) | 1987-07-24 | 1987-07-24 | Exhaust gas purification catalyst |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6430641A JPS6430641A (en) | 1989-02-01 |
| JPH0714481B2 true JPH0714481B2 (en) | 1995-02-22 |
Family
ID=16183167
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62186145A Expired - Lifetime JPH0714481B2 (en) | 1987-07-24 | 1987-07-24 | Exhaust gas purification catalyst |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0714481B2 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01104345A (en) * | 1987-10-15 | 1989-04-21 | Res Dev Corp Of Japan | Oxygen-deficient perovskite catalyst |
| JPH0616851B2 (en) * | 1988-03-25 | 1994-03-09 | 新技術事業団 | Oxygen-defective perovskite catalyst |
| JP2558566B2 (en) * | 1991-11-13 | 1996-11-27 | 財団法人石油産業活性化センター | Catalyst for catalytic reduction of nitrogen oxides |
| JP3311012B2 (en) * | 1992-03-23 | 2002-08-05 | 株式会社豊田中央研究所 | Exhaust gas purification catalyst and exhaust gas purification method |
| KR100326747B1 (en) * | 1998-03-09 | 2002-03-13 | 하나와 요시카즈 | Device for Purifying Oxygen Rich Exhaust Gas |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62186152A (en) * | 1986-02-07 | 1987-08-14 | Matsushita Seiko Co Ltd | Control device of air conditioner |
| JPS62186147A (en) * | 1986-02-08 | 1987-08-14 | Takasago Thermal Eng Co Ltd | Air conditioner unit for clean room |
| JPS62186148A (en) * | 1986-02-10 | 1987-08-14 | Daikin Plant Kk | Room pressure control system |
| JPS62186151A (en) * | 1986-02-10 | 1987-08-14 | Suehiro Sangyo Kk | Method of intake of external air in underground room |
| JPS62186146A (en) * | 1986-02-10 | 1987-08-14 | Taisei Corp | Non-pollution windowless henhouse |
| JPS62186150A (en) * | 1986-02-13 | 1987-08-14 | Fujita Corp | Air cleaner in clean room |
| JPS62186149A (en) * | 1986-02-13 | 1987-08-14 | Fujita Corp | Air cleaner in clean room |
-
1987
- 1987-07-24 JP JP62186145A patent/JPH0714481B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6430641A (en) | 1989-02-01 |
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