JPS6339633A - Catalyst for cleaning exhaust gas - Google Patents
Catalyst for cleaning exhaust gasInfo
- Publication number
- JPS6339633A JPS6339633A JP61180137A JP18013786A JPS6339633A JP S6339633 A JPS6339633 A JP S6339633A JP 61180137 A JP61180137 A JP 61180137A JP 18013786 A JP18013786 A JP 18013786A JP S6339633 A JPS6339633 A JP S6339633A
- Authority
- JP
- Japan
- Prior art keywords
- layer
- alumina
- catalyst
- alumina layer
- piece
- 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
- 239000003054 catalyst Substances 0.000 title claims abstract description 49
- 238000004140 cleaning Methods 0.000 title 1
- 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 70
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Substances [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims abstract description 34
- 229910052746 lanthanum Inorganic materials 0.000 claims abstract description 18
- FZLIPJUXYLNCLC-UHFFFAOYSA-N lanthanum atom Chemical compound [La] FZLIPJUXYLNCLC-UHFFFAOYSA-N 0.000 claims abstract description 18
- 229910052697 platinum Inorganic materials 0.000 claims abstract description 15
- 229910052684 Cerium Inorganic materials 0.000 claims abstract description 9
- GWXLDORMOJMVQZ-UHFFFAOYSA-N cerium Chemical compound [Ce] GWXLDORMOJMVQZ-UHFFFAOYSA-N 0.000 claims abstract description 9
- 229910052763 palladium Inorganic materials 0.000 claims abstract description 8
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 4
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 4
- 239000010948 rhodium Substances 0.000 claims description 36
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 claims description 20
- 229910052703 rhodium Inorganic materials 0.000 claims description 15
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 claims description 15
- 239000007789 gas Substances 0.000 claims description 11
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 claims description 8
- 239000000463 material Substances 0.000 claims description 6
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims description 4
- 229910002091 carbon monoxide Inorganic materials 0.000 claims description 4
- 229930195733 hydrocarbon Natural products 0.000 claims description 2
- 150000002430 hydrocarbons Chemical class 0.000 claims description 2
- 239000010410 layer Substances 0.000 abstract description 88
- CETPSERCERDGAM-UHFFFAOYSA-N ceric oxide Chemical compound O=[Ce]=O CETPSERCERDGAM-UHFFFAOYSA-N 0.000 abstract description 14
- 229910000422 cerium(IV) oxide Inorganic materials 0.000 abstract description 14
- 229910001404 rare earth metal oxide Inorganic materials 0.000 abstract description 13
- 239000010970 precious metal Substances 0.000 abstract description 12
- 230000000694 effects Effects 0.000 abstract description 7
- 229910052751 metal Inorganic materials 0.000 abstract description 7
- 239000002184 metal Substances 0.000 abstract description 7
- 238000007254 oxidation reaction Methods 0.000 abstract description 7
- 230000006866 deterioration Effects 0.000 abstract description 5
- MRELNEQAGSRDBK-UHFFFAOYSA-N lanthanum oxide Inorganic materials [O-2].[O-2].[O-2].[La+3].[La+3] MRELNEQAGSRDBK-UHFFFAOYSA-N 0.000 abstract description 5
- 230000003647 oxidation Effects 0.000 abstract description 5
- 238000009792 diffusion process Methods 0.000 abstract description 2
- 230000003993 interaction Effects 0.000 abstract description 2
- 239000002344 surface layer Substances 0.000 abstract description 2
- 150000002739 metals Chemical class 0.000 abstract 2
- 238000006243 chemical reaction Methods 0.000 abstract 1
- 238000010276 construction Methods 0.000 abstract 1
- KTUFCUMIWABKDW-UHFFFAOYSA-N oxo(oxolanthaniooxy)lanthanum Chemical compound O=[La]O[La]=O KTUFCUMIWABKDW-UHFFFAOYSA-N 0.000 abstract 1
- 239000002002 slurry Substances 0.000 description 10
- 239000002253 acid Substances 0.000 description 8
- 239000000567 combustion gas Substances 0.000 description 7
- 230000000052 comparative effect Effects 0.000 description 7
- 229910000510 noble metal Inorganic materials 0.000 description 7
- 238000000746 purification Methods 0.000 description 7
- SONJTKJMTWTJCT-UHFFFAOYSA-K rhodium(iii) chloride Chemical compound [Cl-].[Cl-].[Cl-].[Rh+3] SONJTKJMTWTJCT-UHFFFAOYSA-K 0.000 description 7
- 238000000034 method Methods 0.000 description 5
- 239000011259 mixed solution Substances 0.000 description 5
- 239000000243 solution Substances 0.000 description 5
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 4
- 230000002378 acidificating effect Effects 0.000 description 4
- 229910000420 cerium oxide Inorganic materials 0.000 description 4
- 238000001816 cooling Methods 0.000 description 4
- 229910017604 nitric acid Inorganic materials 0.000 description 4
- BMMGVYCKOGBVEV-UHFFFAOYSA-N oxo(oxoceriooxy)cerium Chemical compound [Ce]=O.O=[Ce]=O BMMGVYCKOGBVEV-UHFFFAOYSA-N 0.000 description 4
- PIBWKRNGBLPSSY-UHFFFAOYSA-L palladium(II) chloride Chemical compound Cl[Pd]Cl PIBWKRNGBLPSSY-UHFFFAOYSA-L 0.000 description 4
- 229910052573 porcelain Inorganic materials 0.000 description 4
- 238000005245 sintering Methods 0.000 description 4
- QYHYQHPUNPVNDV-UHFFFAOYSA-N aluminane Chemical compound C1CC[AlH]CC1 QYHYQHPUNPVNDV-UHFFFAOYSA-N 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 239000007864 aqueous solution Substances 0.000 description 2
- 239000002131 composite material Substances 0.000 description 2
- 230000009849 deactivation Effects 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 231100000572 poisoning Toxicity 0.000 description 2
- 230000000607 poisoning effect Effects 0.000 description 2
- 229910001018 Cast iron Inorganic materials 0.000 description 1
- 229910002226 La2O2 Inorganic materials 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 239000003245 coal Substances 0.000 description 1
- 239000011247 coating layer Substances 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- WHOPEPSOPUIRQQ-UHFFFAOYSA-N oxoaluminum Chemical compound O1[Al]O[Al]1 WHOPEPSOPUIRQQ-UHFFFAOYSA-N 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000005211 surface analysis Methods 0.000 description 1
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
この発明は、排ガス温度による触媒の熱劣化を防止し、
さらに効率よく排ガス中の炭化水素（ＩＩｃ）、一酸化
炭素（ＣＯ）、窒素酸化物（ＮＯＸ ）を浄化する排ガ
ス浄化用触媒に関する。[Detailed Description of the Invention] (Industrial Application Field) This invention prevents thermal deterioration of a catalyst due to exhaust gas temperature,
Furthermore, the present invention relates to an exhaust gas purification catalyst that efficiently purifies hydrocarbons (IIc), carbon monoxide (CO), and nitrogen oxides (NOX) in exhaust gas.
（従来の技術）
従来、排ガス浄化用触媒としては、あらかじめセリウム
を含有させた活性アルミナ粉末をモノリス担体基材の表
面に付着させた後、白金（Ｐ ｔ）、ロジウム（Ｒｈ）
、パラジウム（Ｐｄ）等を貴金属をそれぞれ単独あるい
は、組み合わせて担持した触媒（特開昭５２−１１６７
７９号、特開昭５４−１５９３９１号公報）、被毒劣化
しやすい成分を内層とする触媒（特開昭５９−１２７６
４９号公報）、貴金属の担持されていない金属酸化物層
を間又は外部に設けることで貴金属の相互移動を防ぐ触
媒（特開昭５７−１０５２４０号公報）、貴金属の濃度
を変えた触媒（特開昭６０−３１８２８号公報）等が提
供されている。(Prior art) Conventionally, as a catalyst for exhaust gas purification, activated alumina powder containing cerium is attached to the surface of a monolithic carrier base material, and then platinum (Pt), rhodium (Rh)
Catalysts supporting noble metals such as palladium (Pd) individually or in combination (Japanese Patent Application Laid-Open No. 52-1167
No. 79, JP-A-54-159391), a catalyst with an inner layer containing components that are susceptible to poisoning and deterioration (JP-A-59-1276)
49 Publication), a catalyst that prevents the mutual movement of precious metals by providing a metal oxide layer between or outside of which no precious metal is supported (Japanese Unexamined Patent Publication No. 57-105240), a catalyst with a different concentration of precious metal (Japanese Unexamined Patent Publication No. 105240/1982), Publication No. 31828/1983), etc. are provided.
（発明が解決しようとする問題点）
しかしながら、このような従来の排ガス浄化用触媒にあ
っては、ＨＣ，ＧＯ，ＮＯＸを同時に効率よく浄化する
三元触媒の貴金属種として不可欠であるロジウム（Ｒｈ
）の大部分が、高温な排ガスと直接接触する構造となっ
ていたため、高温な排ガスにより、Ｒｈが熱劣化（酸化
、シンタリング）ＬＲｈ本来の触媒活性を速く失い失活
するという問題点があった。(Problems to be Solved by the Invention) However, in such conventional exhaust gas purification catalysts, rhodium (Rh
) had a structure in which they were in direct contact with high-temperature exhaust gas, which caused the problem of thermal deterioration (oxidation, sintering) of Rh, causing rapid loss of LRh's original catalytic activity and deactivation. Ta.
（問題点を解決するだめの手段）
発明者は、上記従来の問題点である三元触媒の貴金属種
として不可欠のロジウム（Ｒｈ）の早期失活を防止ずべ
く種々研究の結果、無機質担体基材の表面に設けるアル
ミナ層につき貴金属を担持する希土類酸化物（Ｌａｚｙ
、、、 Ｃｅ０ｚ）を含むアルミナ層を組成的に多層構
造にし、Ｒｈを内側の内層アルミナ層により多く、或い
はすべて担持させ、貴金属、希土類酸化物の相互作用よ
り熱劣化（酸化、シンタリング）を防止し、また構造的
に酸化反応を表層で主に行わせることにより酸素（０□
）の内層への拡散を少なくすることによりＲｈの酸化を
防止し、触媒の活性を長期間保持し得ることを知見しこ
の発明を達成するに至った。(Means to Solve the Problem) The inventor has conducted various researches to prevent the early deactivation of rhodium (Rh), which is essential as a precious metal species in three-way catalysts, which is the problem with the conventional three-way catalyst. The alumina layer provided on the surface of the material contains rare earth oxides (Lazy
The alumina layer containing (Ce0z) is made into a multilayer composition composition, and Rh is carried in a large amount or all in the inner alumina layer to prevent thermal deterioration (oxidation, sintering) from the interaction of noble metals and rare earth oxides. By preventing the oxidation reaction from occurring mainly in the surface layer, oxygen (0□
The inventors have found that by reducing the diffusion of Rh into the inner layer, the oxidation of Rh can be prevented and the activity of the catalyst can be maintained for a long period of time, and this invention has been achieved.
即ちこの発明の排ガス浄化用触媒は、無機質担体基材の
表面に多層構造でアルミナ層を備え、これ等のアルミナ
層の内、内側のアルミナ層はランタンを含浸させた活性
アルミナとアルミゾルから構成され、主としてロジウム
を担持し、表面側のアルミナ層はセリウムを含浸させた
活性アルミナとアルミナゾルから構成され、主として白
金とパラジウムのうち少なくとも１種を担持したことを
特徴とする。That is, the exhaust gas purifying catalyst of the present invention has an alumina layer in a multilayer structure on the surface of an inorganic carrier base material, and among these alumina layers, the inner alumina layer is composed of activated alumina impregnated with lanthanum and aluminum sol. The alumina layer on the surface side is composed of activated alumina impregnated with cerium and alumina sol, and mainly supports at least one of platinum and palladium.
この発明の排ガス浄化用触媒は、貴金属を担持するアル
ミナ層が多層化されており、かつ貴金属分布に濃度差が
あり、内側の内層アルミナ層には希土類酸化物としてＬ
ａ、Ｏ，が含まれ、貴金属種としては主にＲｈが含まれ
ている。また表面側の外層アルミナ層には希土類酸化物
としてＣｅＯ□が含まれ、貴金属種としては主にＰｔ、
Ｐｄが含まれている。第１図はこの発明の触媒の構造
を示すため一例触媒の断面の一部分を拡大して示す図で
、１はモノリス担体基材、２はランタンを含むアルミナ
層で、主としてＲｈが担持されており、３はセリウムを
含むアルミナ層で、主としてｐｔおよび／またはＰｄが
担持されている。The exhaust gas purification catalyst of this invention has multiple alumina layers supporting precious metals, and there are differences in the concentration of precious metals, and the inner alumina layer contains L as a rare earth oxide.
a, O, and mainly Rh as the noble metal species. In addition, the outer alumina layer on the surface side contains CeO□ as a rare earth oxide, and the noble metal species are mainly Pt,
Contains Pd. FIG. 1 is an enlarged view of a part of the cross section of an example catalyst to show the structure of the catalyst of the present invention, in which 1 is a monolith carrier base material, 2 is an alumina layer containing lanthanum, and Rh is mainly supported. , 3 is an alumina layer containing cerium, and mainly supports pt and/or Pd.
次にこの発明の多層構造触媒の調製方法を説明する。触
媒の調製は種々の方法で行うことができるが、第１の望
ましい方法は、ＲｈがＬａに選択吸着しやすいことを知
見したことに基づく調製法である。すなわち、内層にラ
ンタンを含むアルミナ層を形成し、その後外層にセリア
を含むアルミナ層を形成し、多層構造のアルミナ層を持
つ担体を準備する。しかるのち、白金、パラジウムのう
ち少なくとも１種およびロジウムの混合溶液に１回浸漬
しただけで、内層にＲｈを多く担持させることを特徴と
する。Next, a method for preparing the multilayer structure catalyst of the present invention will be explained. Although the catalyst can be prepared by various methods, the first preferred method is a preparation method based on the finding that Rh tends to be selectively adsorbed onto La. That is, an alumina layer containing lanthanum is formed as an inner layer, and then an alumina layer containing ceria is formed as an outer layer, thereby preparing a carrier having a multilayer structure of alumina layers. The inner layer is then immersed in a mixed solution of at least one of platinum, palladium, and rhodium once, thereby allowing the inner layer to support a large amount of Rh.
第２の望ましい方法は、まず内層にＬａを含むアルミナ
層を形成し、塩化ロジウム溶液中に浸清し、内層のラン
タンを含むアルミナ層にＲｈを担持し第１Ｎを形成する
。A second preferred method is to first form an alumina layer containing La as an inner layer, immerse it in a rhodium chloride solution, and support Rh on the inner alumina layer containing lanthanum to form the first N layer.
次に、Ｃｅを含むアルミナ層を上記第１層上にコーティ
ングし外層を形成し、塩化白金酸、塩化パラジウムのう
ち少なくとも１種の溶液に浸漬し外層のセリウムを含む
、アルミナ層にＰｔ、 Ｐｄのうち少なくとも１種を担
持させることを特徴とする。Next, an alumina layer containing Ce is coated on the first layer to form an outer layer, and is immersed in a solution of at least one of chloroplatinic acid and palladium chloride to coat the alumina layer containing cerium with Pt and Pd. It is characterized by supporting at least one of these.
（作用）
アルミナ層にランタンとロジウムを共有させると、高温
な排ガス中においてペロブスカイト型複合酸化物ＬａＲ
ｈ０３が形成され、安定化され、Ｒｈの酸化が防止され
、Ｒｈの活性が維持される。また、触媒担体であるアル
ミナのα転位は貴金属シンタリングの一因となるが８０
０℃以上でペロブスカイト型複合酸化物ＬａＡｊ！０３
または、Ｌａ２Ｏ２・ＩＩＡ ｊ２ ｚ０３を形成しア
ルミナ層を安定化させアルミナのα転位を約１４００℃
まで上昇させるため貴金属のシンタリングが防げる。(Function) When lanthanum and rhodium are shared in the alumina layer, perovskite-type composite oxide LaR is formed in high-temperature exhaust gas.
h03 is formed and stabilized, preventing Rh oxidation and maintaining Rh activity. In addition, α-rearrangement of alumina, which is a catalyst support, causes noble metal sintering, but 80
Perovskite-type composite oxide LaAj! at 0°C or higher! 03
Alternatively, La2O2・IIA j2 z03 is formed to stabilize the alumina layer and the α dislocation of alumina is heated to about 1400℃.
This prevents sintering of precious metals.
以上のような作用をもつＡｌ２Ｏ２・ＬａｚＯ＋ ・
Ｒｈ層をさらに多層構造の内層に位置させることにより
、ＲｈへのＣＯ被毒等を防止し、合わせて三元触媒とし
て不可欠であるＲｈの耐久性を、さらに向上することが
できる。ちなみに、外層はＡ 、ｇ ｚｏ：＋ ・Ｃ
ｅＯｚ・Ｐ ｔ （Ｐｄ）が主成分であり、セリアの０
２ストレージ効果を最大に利用しＰｔ（Ｐｄ）の酸化反
応を促進させるものである。この結果として三元触媒の
性能が向上する。Al2O2, LazO+, which has the above-mentioned effects
By further locating the Rh layer in the inner layer of the multilayer structure, it is possible to prevent CO poisoning of Rh and further improve the durability of Rh, which is essential as a three-way catalyst. By the way, the outer layer is A, g zo: + ・C
eOz・P t (Pd) is the main component, and the 0 of ceria
This method utilizes the 2 storage effect to the maximum to promote the oxidation reaction of Pt (Pd). As a result, the performance of the three-way catalyst is improved.
（実施例）
以下、この発明を実施例、比較例および試験例で説明す
る。(Examples) The present invention will be described below with reference to Examples, Comparative Examples, and Test Examples.
尖籐■土
ランタンを、金属換算で３重量％含む活性アルミナ１１
６７ｇ、硝酸酸性アルミナゾル２４７８ ｇ 、酸化ラ
ンタン３５５ｇを磁製ボールミルに投入し、毎分８０回
転で８時間粉砕した後、得られたスラリーを０．９ β
のモノリス担体上にコーティングし、ランタンを含むア
ルミナ層（内層）を形成した。コート量は８０ｇ／Ｊで
あった。Activated alumina 11 containing 3% by weight of earth lanthanum (metal equivalent)
67 g of nitric acid acidic alumina sol, 2478 g of lanthanum oxide, and 355 g of lanthanum oxide were placed in a porcelain ball mill and ground at 80 revolutions per minute for 8 hours, and the resulting slurry was 0.9 β
was coated on a monolithic support to form an alumina layer (inner layer) containing lanthanum. The coating amount was 80 g/J.
次に、セリアを金属換算で３重量％含む活性アルミナ１
０４３ ｇ 、硝酸酸性アルミナゾル２２６４ ｇ 、
酸化セリウム６９３ｇを磁製ボールミルに投入し、毎分
８０回転で８時間粉砕した後、得られたスラリーを上記
アルミナＮ（内層）を形成した担体上にコーティングし
、セリアを含むアルミナ層（中層）を形成した。コート
量は８５ｇ／Ｍであった。Next, activated alumina 1 containing 3% by weight of ceria in terms of metal
043 g, nitric acid acidic alumina sol 2264 g,
After putting 693 g of cerium oxide into a porcelain ball mill and pulverizing it at 80 revolutions per minute for 8 hours, the resulting slurry was coated on the carrier on which the alumina N (inner layer) was formed, and an alumina layer (middle layer) containing ceria was formed. was formed. The coating amount was 85 g/M.
さらに、セリアを金属換算で３重量％含む活性アルミナ
９６０ｇ、硝酸酸性アルミナゾル２３９２ ｇ 。Furthermore, 960 g of activated alumina containing 3% by weight of ceria in terms of metal, and 2392 g of nitric acid acidic alumina sol.
酸化セリウム６４８ｇを磁製ボールミルに投入し、毎分
８０回転で８時間粉砕した後、得られたスラリーを上記
アルミナ層（内層、中層）を形成した担体上にコーティ
ングしセリアを含むアルミナ層（外層）を形成した。コ
ートｉは１００ｇ／Ａであった。しかるのち、６５０℃
で２時間電気炉で焼成し、第１層にＬａを、第２層、第
３層にＣｅを含む多層構造のアルミナ層を持つ担体を得
た。ついで、この担体を塩化白金酸と塩化ロジウムの混
合水溶液に浸漬し、白金、ロジウムの担持量が白金１．
０１ｇ／個、ロジウム０．１０ｇ／個となるようにした
後、燃焼ガス気流中６００″Ｃで２時間焼成し、実施例
１の触媒Ａを得た。この触媒Ａは、希土類酸化物を含む
アルミナコート層２２５ｇ／個であり、Ｌａ、０３１９
．１ｇ／個、Ｃｅ０ｚ６７．９ ｇ ／個を含んでいた
。After putting 648 g of cerium oxide into a porcelain ball mill and grinding at 80 revolutions per minute for 8 hours, the resulting slurry was coated on the carrier on which the alumina layer (inner layer, middle layer) was formed. ) was formed. Coat i was 100 g/A. After that, 650℃
The resultant was fired in an electric furnace for 2 hours to obtain a support having a multilayered alumina layer including La in the first layer and Ce in the second and third layers. Next, this carrier was immersed in a mixed aqueous solution of chloroplatinic acid and rhodium chloride, and the amount of supported platinum and rhodium was 1.5% of platinum.
01 g/piece and rhodium 0.10 g/piece, and then calcined in a combustion gas stream at 600''C for 2 hours to obtain catalyst A of Example 1. This catalyst A contains a rare earth oxide. Alumina coat layer 225g/piece, La, 0319
．． It contained 1 g/piece and 67.9 g/piece of Ce0z.
Ｘ線マイクロアナライザー（ＸＭＡ）にて、線分析およ
び面分析した結果、Ｌａを含むアルミナ層（内層）には
主にＲｈが、Ｃｅを含むアルミナＮ（中、外層）には主
にｐｔが、担持されていた。As a result of line analysis and surface analysis using an X-ray microanalyzer (XMA), the alumina layer (inner layer) containing La mainly contains Rh, and the alumina N (middle and outer layer) containing Ce mainly contains pt. It was being carried.
大施斑主
実施例１と同様に０．９１のモノリス担体上にランタン
を含むアルミナＮ（内層）を形成しく８０ｇ／β）、次
に６５０℃で１時間電気炉で焼成し冷却後塩化ロジウム
溶液に浸漬し、ロジウムの担持量が０．１０ｇ／個とな
るようにした後燃焼ガス気流中６００℃で１時間焼成し
た。次に、実施例１の中層用のものと同様にセリアを含
むアルミナスラリーを調製し、このスラリーを上記のＲ
ｈを担持したランタンを含むアルミナ層の上に、コーテ
ィングし外層を形成した（１６０ ｇ ／ ｉｔ ）。As in Example 1, alumina N (inner layer) containing lanthanum was formed on a monolithic support of 0.91 g/β), then fired in an electric furnace at 650°C for 1 hour, and after cooling, rhodium chloride was added. After being immersed in a solution so that the amount of rhodium supported was 0.10 g/piece, it was fired at 600° C. for 1 hour in a combustion gas stream. Next, an alumina slurry containing ceria was prepared in the same manner as that for the middle layer in Example 1, and this slurry was mixed with the above R
An outer layer was formed by coating on top of the alumina layer containing lanthanum loaded with h (160 g/it).
６５０℃で、１時間電気炉で焼成し、冷却した後、塩化
白金酸溶液に浸漬し、白金の担持量が１．ＯＬ ｇ ／
個となるようにした後燃焼ガス気流中、６００℃で１時
間焼成し、実施例２の触媒Ｂを得た。この触媒Ｂは、希
土類酸化物を含むアルミナコート層２２５ｇ／個であり
、ＬａｚＯｓ １９．１ ｇ ／個、Ｃｅ０ｚ６７．９
ｇ ／個を含んでいた。After firing in an electric furnace at 650°C for 1 hour and cooling, immersion in a chloroplatinic acid solution was performed until the amount of platinum supported was 1. OL g/
After this, the catalyst was fired at 600° C. for 1 hour in a combustion gas stream to obtain catalyst B of Example 2. This catalyst B has an alumina coat layer of 225 g/piece containing a rare earth oxide, LazOs 19.1 g/piece, and CeOz 67.9 g/piece.
g/piece.
工較炭上
実施例１の内層用ランタンを含むアルミナのスラリーと
、中層用セリアを含むスラリーを１＝２の割合で混合し
、ランタンとセリアを含むスラリーを調製した。これを
０．９１のモノリス担体上に３回コーティングし、６５
０℃の電気炉で２時間焼成しランタン、セリアの濃度分
布が、均一なアルミナ層をもつ担体とした。ついでこの
担体を塩化白金酸と塩化ロジウムの混合水溶液に浸漬し
、白金、ロジウムの担持量が白金１．０１ ｇ ／個、
ロジウム０．１０ ｇ ／個となるようにした後、燃焼
ガス気流中６００℃で２時間焼成し、比較例１の触媒Ｃ
を得た。この触媒Ｃは、希土類酸化物を含むアルミナコ
ート層２２５ｇ／個であり、ＬａｚＯ＋１９．１ ｇ
／個、Ｃｅ０ｚ６７．９ ｇ ／個を含んでいた。On engineered coal, the alumina slurry containing lanthanum for the inner layer of Example 1 and the slurry containing ceria for the middle layer were mixed at a ratio of 1=2 to prepare a slurry containing lanthanum and ceria. This was coated three times on a 0.91 monolithic support, and 65
It was fired in an electric furnace at 0° C. for 2 hours to obtain a carrier having an alumina layer with a uniform concentration distribution of lanthanum and ceria. Next, this carrier was immersed in a mixed aqueous solution of chloroplatinic acid and rhodium chloride, and the amount of platinum and rhodium supported was 1.01 g of platinum/piece.
After adjusting the rhodium content to 0.10 g/piece, it was calcined in a combustion gas stream at 600°C for 2 hours to obtain the catalyst C of Comparative Example 1.
I got it. This catalyst C has 225 g/piece of alumina coat layer containing rare earth oxide, and LazO+19.1 g
/piece, and 67.9 g/piece of Ce0z.
此笠斑１
セリウムを、金属換算で３重量％含む活性アルミナ１０
１５ ｇ、硝酸酸性アルミナゾル２３０７ ｇ、酸化セ
リウム６７８ｇを磁製ボールミルに投入し、毎分８０回
転で、８時間粉砕した後、得られたスラリーを０．９１
のモノリス担体上に３回コーティングし、セリアを含む
アルミナ層を形成した。しかるのち、６５０℃で２時間
電気炉で、焼成を行いセリアを含むアルミナ層を持つ担
体とした。ついで、この担体を塩化白金酸と塩化ロジウ
ムの混合溶液に浸漬し、白金、ロジウムの担持量が白金
１．０１ ｇ ／個、ロジウム０．１０ｇ／個になるよ
うにした後、燃焼ガス気流中６００°Ｃで２時間焼成し
、比較例２の触媒りを得た。この触媒りは、希土類酸化
物を含むアルミナコート層２２５ｇ／個であり、Ｃ１３
０２８７，Ｏｇ ／個を含んでいた。Konokasama 1 Activated alumina containing 3% by weight of cerium in terms of metal 10
15 g of nitric acid acidic alumina sol, 2307 g of cerium oxide, and 678 g of cerium oxide were placed in a porcelain ball mill and milled at 80 revolutions per minute for 8 hours.
was coated three times on a monolithic support to form an alumina layer containing ceria. Thereafter, it was fired in an electric furnace at 650° C. for 2 hours to obtain a carrier having an alumina layer containing ceria. Next, this carrier was immersed in a mixed solution of chloroplatinic acid and rhodium chloride so that the amount of platinum and rhodium supported was 1.01 g/piece of platinum and 0.10 g/piece of rhodium, and then soaked in a combustion gas stream. The catalyst was calcined at 600°C for 2 hours to obtain a catalyst of Comparative Example 2. This catalyst has an alumina coating layer of 225 g/piece containing rare earth oxide, and has a C13
It contained 0287,0g/piece.
去籐炭主
実施例１と同様に０．９１のモノリス担体上にランタン
を含むアルミナ層（内層）を形成した。コート量は８０
ｇ／ｌであった。次に６５０°Ｃで１時間電気炉で焼成
した。冷却後、塩化ロジウム溶液に浸漬し、ロジウムの
担持量が０．１ｇ／個になるようにした後、燃焼ガス気
流中６００℃で１時間焼成した。次に実施例１と同様に
中層、外層用のセリアを含むアルミナスラリーを調製し
、このスラリーを上記Ｒｈを担持したランタンを含むア
ルミナ層（内層）の上にコーティングし、中層、外層を
形成した。コーｔＶは中層１．外層合わせて１６０ｇ／
ｌであった。しかるのち６５０℃で１時間電気炉で焼成
した。冷却後、塩化白金酸と塩化パラジウムの混合溶液
に浸漬し、白金の担持量が０．５０ｇ／個、パラジウム
の担持量が０．５０ ｇ ／個となるようにした後、燃
焼ガス気流中６００°Ｃで１時間焼成し、実施例３の触
媒Ｅを得た。この触媒Ｅは希土類酸化物を含むアルミナ
コート層が２２５ｇ／個であり、ＬａｚＯ：＋ １９．
１ ｇ ／個、Ｃｅ０ｚ６７．９ ｇ ／個を含んでい
た。An alumina layer (inner layer) containing lanthanum was formed on a 0.91 monolithic support in the same manner as in Example 1, in which the cast iron was removed. Coat amount is 80
g/l. Next, it was fired in an electric furnace at 650°C for 1 hour. After cooling, it was immersed in a rhodium chloride solution so that the amount of rhodium supported was 0.1 g/piece, and then fired at 600° C. for 1 hour in a combustion gas stream. Next, an alumina slurry containing ceria for the middle and outer layers was prepared in the same manner as in Example 1, and this slurry was coated on the alumina layer (inner layer) containing lanthanum carrying Rh to form the middle and outer layers. . Coat tV is middle layer 1. Total outer layer 160g/
It was l. Thereafter, it was fired in an electric furnace at 650°C for 1 hour. After cooling, it was immersed in a mixed solution of chloroplatinic acid and palladium chloride so that the amount of platinum supported was 0.50 g/piece and the amount of palladium supported was 0.50 g/piece, and then 600 g/piece was immersed in a mixed solution of chloroplatinic acid and palladium chloride. The catalyst was calcined at °C for 1 hour to obtain catalyst E of Example 3. This catalyst E has 225 g/piece of alumina coat layer containing a rare earth oxide, and LazO: + 19.
It contained 1 g/piece and 67.9 g/piece of Ce0z.
止笠玉ユ
比較例２と同様にセリアを含むアルミナ層を設けた担体
を用意した。この担体を塩化白金酸と塩化パラジウムと
塩化ロジウムの混合溶液に浸漬し、白金の担持量が０．
５０ｇ／個、パラジウムの担持量が０．５０ ｇ ／個
、ロジウムの担持量が０．１０ ｇ ／個となるように
した後、燃焼ガス気流中６００″Ｃで１時間焼成し、比
較例３の触媒Ｆを得た。この触媒Ｆは希土類酸化物を含
むアルミナコート層２２５ｇ／個であり、Ｃｅ０Ｊ７．
０ ｇ ／個を含んでいた。A carrier provided with an alumina layer containing ceria was prepared in the same manner as Comparative Example 2. This carrier was immersed in a mixed solution of chloroplatinic acid, palladium chloride, and rhodium chloride, and the amount of platinum supported was 0.
After adjusting the amount of supported palladium to be 0.50 g/piece and the amount of supported rhodium to be 0.10 g/piece, they were fired at 600''C in a combustion gas stream for 1 hour, and Comparative Example 3 A catalyst F was obtained.This catalyst F had an alumina coat layer of 225 g/piece containing a rare earth oxide, and had a CeOJ7.
It contained 0 g/piece.
拭狂皿
実施例１．２および３で得た触媒Ａ、 ＢおよびＥ１
比較例１，２および３で得た触媒Ｃ，ＤおよびＦの各々
を下記条件でエンジン耐久を行い、１０モードエミツシ
ヨンの浄化率を測定し、浄化率をｂ工； として第１表
に示す。Catalysts A, B and E1 obtained in Wiping dish Examples 1.2 and 3
Each of the catalysts C, D and F obtained in Comparative Examples 1, 2 and 3 was subjected to engine durability under the following conditions, the purification rate of 10 mode emission was measured, and the purification rate is shown in Table 1 as show.
耐久試験条件
触媒 モノリス型貴金属触媒触媒出口温度
約７５０℃
空間速度 約７万Ｈｒ−’
耐久時間 １００時間
エンジン 排気量 ２２００ｃｃ車両評価条件
日量自動車（株）製 １８００ｃｃ
１０モードベースエミツシヨン
ＩＣ１，５〜１．８ ｇ ／ ｋｍ
ＣＯ５，０〜６．０ｇ／ｋｍ
ＮＯ０，９〜１．０ ｇ／ｋａ＋
第１表より明らかなように、実施例の触媒は、比較例に
比べ、より良い性能であることが判る。Durability test conditions Catalyst Monolithic precious metal catalyst Catalyst outlet temperature
Approximately 750°C Space velocity Approximately 70,000 Hr-' Endurance time 100 hours Engine displacement 2200cc Vehicle evaluation conditions Nichijo Jidosha Co., Ltd. 1800cc 10 mode base emission IC 1.5 to 1.8 g/km CO5.0 to 6 .0 g/km NO0.9 to 1.0 g/ka+ As is clear from Table 1, it can be seen that the catalyst of the example has better performance than the comparative example.
（発明の効果）
以上説明してきたように、この発明によれば、触媒を組
成的に多層構造にて、その内層をランタンを含むアルミ
ナ層で形成し、貴金属種として主にＲｈを担持し、外層
は、セリウムを含むアルミナ層で形成し、貴金属種とし
て主にＰ ｔ （Ｐｄ）を担持する構造としたため、得
られた触媒は、著しく浄化率が向上し、耐久性が改善で
き、低貴金属化できるという効果が得られる。(Effects of the Invention) As explained above, according to the present invention, the catalyst has a multi-layered structure, the inner layer of which is formed of an alumina layer containing lanthanum, and Rh is mainly supported as a noble metal species, The outer layer is formed of an alumina layer containing cerium, and has a structure that supports mainly Pt (Pd) as a noble metal species, so the resulting catalyst has a significantly improved purification rate, improved durability, and a low precious metal content. This has the effect of being able to be converted into
第１図は、この発明の触媒の構造を示すための一例触媒
の拡大部分断面図である。
１・・・モノリス担体基材
２・・・ランタンを含むアルミナ層で、主としてＲｈが
担 持されている。
３・・・セリウムを含むアルミナ層で、主としてＰｔ（
Ｐｄ） が担持されている。
第１図FIG. 1 is an enlarged partial sectional view of an example catalyst for showing the structure of the catalyst of the present invention. 1... Monolith carrier base material 2... An alumina layer containing lanthanum, which mainly supports Rh. 3...Alumina layer containing cerium, mainly Pt (
Pd) is supported. Figure 1
Claims (1)
え、これ等のアルミナ層の内、内側のアルミナ層はラン
タンを含浸させた活性アルミナとアルミゾルから構成さ
れ、主としてロジウムを担持し、表面側のアルミナ層は
セリウムを含浸させた活性アルミナとアルミゾルから構
成され、主として白金とパラジウムのうち少なくとも１
種を担持したことを特徴とする排ガス中の炭化水素、一
酸化炭素および窒素酸化物を浄化する排ガス浄化用触媒
。1. The surface of the inorganic carrier base material is equipped with an alumina layer with a multilayer structure. Among these alumina layers, the inner alumina layer is composed of activated alumina and aluminum sol impregnated with lanthanum, and mainly supports rhodium, and the surface The side alumina layer is composed of activated alumina impregnated with cerium and aluminum sol, and is mainly composed of at least one of platinum and palladium.
An exhaust gas purifying catalyst for purifying hydrocarbons, carbon monoxide, and nitrogen oxides in exhaust gas, characterized by supporting a species.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61180137A JPS6339633A (en) | 1986-08-01 | 1986-08-01 | Catalyst for cleaning exhaust gas |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61180137A JPS6339633A (en) | 1986-08-01 | 1986-08-01 | Catalyst for cleaning exhaust gas |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6339633A true JPS6339633A (en) | 1988-02-20 |
Family
ID=16078055
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61180137A Pending JPS6339633A (en) | 1986-08-01 | 1986-08-01 | Catalyst for cleaning exhaust gas |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6339633A (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4980333A (en) * | 1986-06-27 | 1990-12-25 | Mobil Oil Corporation | Perovskite-related layered oxides containing interspathic polymeric oxide |
| JPH04265155A (en) * | 1991-02-18 | 1992-09-21 | Cataler Kogyo Kk | Catalyst for purification of exhaust gas |
| US5628975A (en) * | 1989-02-06 | 1997-05-13 | Nippon Shokubai Kagaku Kogyo Co., Ltd. | Method for purifying exhaust gas from a diesel engine |
| WO1998045026A1 (en) * | 1997-04-07 | 1998-10-15 | Engelhard Corporation | Layered catalyst composite |
| WO2003011438A1 (en) * | 2001-07-30 | 2003-02-13 | Valtion Teknillinen Tutkimuskeskus | Method for catalytic reduction of nitrogen oxides and catalyst for use therein |
| JP2010167381A (en) * | 2009-01-23 | 2010-08-05 | Toyota Motor Corp | Exhaust gas cleaning catalyst |
| WO2010142635A3 (en) * | 2009-06-08 | 2011-03-24 | Süd-Chemie AG | Method for producing a three-way catalyst comprising rhodium and platinum supported on separate oxide supports, said method having only one coating step and calcining step |
| WO2017203863A1 (en) * | 2016-05-25 | 2017-11-30 | エヌ・イーケムキャット株式会社 | Gasoline engine exhaust gas purification three-way catalyst |
-
1986
- 1986-08-01 JP JP61180137A patent/JPS6339633A/en active Pending
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4980333A (en) * | 1986-06-27 | 1990-12-25 | Mobil Oil Corporation | Perovskite-related layered oxides containing interspathic polymeric oxide |
| US5628975A (en) * | 1989-02-06 | 1997-05-13 | Nippon Shokubai Kagaku Kogyo Co., Ltd. | Method for purifying exhaust gas from a diesel engine |
| JPH04265155A (en) * | 1991-02-18 | 1992-09-21 | Cataler Kogyo Kk | Catalyst for purification of exhaust gas |
| WO1998045026A1 (en) * | 1997-04-07 | 1998-10-15 | Engelhard Corporation | Layered catalyst composite |
| WO2003011438A1 (en) * | 2001-07-30 | 2003-02-13 | Valtion Teknillinen Tutkimuskeskus | Method for catalytic reduction of nitrogen oxides and catalyst for use therein |
| JP2010167381A (en) * | 2009-01-23 | 2010-08-05 | Toyota Motor Corp | Exhaust gas cleaning catalyst |
| WO2010142635A3 (en) * | 2009-06-08 | 2011-03-24 | Süd-Chemie AG | Method for producing a three-way catalyst comprising rhodium and platinum supported on separate oxide supports, said method having only one coating step and calcining step |
| CN102497926A (en) * | 2009-06-08 | 2012-06-13 | 南方化学股份公司 | Method for producing a three-way catalyst comprising rhodium and platinum supported on separate oxide supports, said method having only one coating step and calcining step |
| WO2017203863A1 (en) * | 2016-05-25 | 2017-11-30 | エヌ・イーケムキャット株式会社 | Gasoline engine exhaust gas purification three-way catalyst |
| JPWO2017203863A1 (en) * | 2016-05-25 | 2019-04-25 | エヌ・イーケムキャット株式会社 | Three-way catalyst for purification of gasoline engine exhaust gas |
| US10765998B2 (en) | 2016-05-25 | 2020-09-08 | N.E. Chemcat Corporation | Three-way catalyst for purifying gasoline engine exhaust gas |
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