JP2618316B2 - Catalyst for catalytic reduction of nitrogen oxides - Google Patents
Catalyst for catalytic reduction of nitrogen oxidesInfo
- Publication number
- JP2618316B2 JP2618316B2 JP4288376A JP28837692A JP2618316B2 JP 2618316 B2 JP2618316 B2 JP 2618316B2 JP 4288376 A JP4288376 A JP 4288376A JP 28837692 A JP28837692 A JP 28837692A JP 2618316 B2 JP2618316 B2 JP 2618316B2
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- Japan
- Prior art keywords
- alumina
- weight
- catalyst
- oxide
- ion
- Prior art date
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Description
【０００１】[0001]
【産業上の利用分野】本発明は、炭化水素を還元剤とし
て使用する窒素酸化物接触還元用触媒に関し、詳しく
は、工場、自動車等から排出される排ガスの中に含まれ
る有害な窒素酸化物を還元除去するのに好適である窒素
酸化物接触還元用触媒に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catalyst for catalytic reduction of nitrogen oxides using a hydrocarbon as a reducing agent, and more particularly to harmful nitrogen oxides contained in exhaust gas discharged from factories, automobiles and the like. The present invention relates to a catalyst for catalytic reduction of nitrogen oxides, which is suitable for reducing and removing nitrogen oxides.
【０００２】[0002]
【従来の技術】従来、排ガス中に含まれる窒素酸化物
は、窒素酸化物を酸化した後、アルカリに吸収させる方
法や、アンモニア、水素、一酸化炭素、炭化水素等の還
元剤を用いて、窒素に変換する方法等によつて除去され
ている。しかしながら、前者の方法によれば、生成する
アルカリ廃液を処理して、公害の発生を防止する方策が
必要である。他方、後者の方法によれば、還元剤として
アンモニアを用いるときは、これが排ガス中のイオウ酸
化物と反応して塩類を生成し、その結果、触媒の還元活
性が低下する問題がある。また、水素、一酸化炭素、炭
化水素等を還元剤として用いる場合でも、これらが低濃
度に存在する窒素酸化物よりも高濃度に存在する酸素と
反応するため、窒素酸化物を低減するためには多量の還
元剤を必要とするという問題がある。2. Description of the Related Art Conventionally, nitrogen oxides contained in exhaust gas are obtained by oxidizing the nitrogen oxides and then absorbing them into an alkali, or by using a reducing agent such as ammonia, hydrogen, carbon monoxide, or a hydrocarbon. It has been removed by a method of converting to nitrogen. However, according to the former method, it is necessary to take measures for treating the generated alkaline waste liquid to prevent the occurrence of pollution. On the other hand, according to the latter method, when ammonia is used as the reducing agent, it reacts with the sulfur oxide in the exhaust gas to form salts, and as a result, there is a problem that the reduction activity of the catalyst is reduced. In addition, even when hydrogen, carbon monoxide, hydrocarbons, and the like are used as a reducing agent, since they react with oxygen present at a higher concentration than nitrogen oxide present at a lower concentration, it is necessary to reduce nitrogen oxides. Has the problem that a large amount of reducing agent is required.
【０００３】このため、最近では、還元剤の不存在下に
窒素酸化物を触媒にて直接分解する方法も提案されてい
るが、しかし、従来知られているそのような触媒は、窒
素酸化物分解活性が低いために実用に供し難いという問
題がある。また、炭化水素や含酸素化合物を還元剤とし
て用いる新たな窒素酸化物接触還元用触媒として、Ｈ型
ゼオライトやＣｕイオン交換ＺＳＭ−５等が提案されて
いる。特に、Ｈ型ＺＳＭ−５（ＳｉＯ2 ／Ａｌ2 Ｏ3 モ
ル比＝３０〜４０）が最適であるとされている。しかし
ながら、このようなＨ型ＺＳＭ−５でも、未だ十分な還
元活性を有するものとはいい難く、特に、ガス中に水分
が含まれるとき、ゼオライト構造体中のアルミニウムが
脱アルミニウムして、性能が急激に低下するので、一層
高い還元活性を有し、更に、ガスが水分を含有する場合
にも、すぐれた耐久性を有する窒素酸化物接触還元用触
媒が要望されている。[0003] For this reason, a method of directly decomposing nitrogen oxides with a catalyst in the absence of a reducing agent has recently been proposed. There is a problem that it is difficult to put to practical use due to low decomposition activity. Further, as a new catalyst for catalytic reduction of nitrogen oxides using a hydrocarbon or an oxygen-containing compound as a reducing agent, H-type zeolite, Cu ion exchange ZSM-5, and the like have been proposed. In particular, H type ZSM-5 (SiO 2 / Al 2 O 3 molar ratio = 30 to 40) are to be optimal. However, even with such H-type ZSM-5, it is still difficult to say that the H-type ZSM-5 has a sufficient reducing activity. In particular, when moisture is contained in the gas, the aluminum in the zeolite structure is dealuminated and the performance is reduced. There is a demand for a catalyst for catalytic reduction of nitrogen oxides which has a higher reduction activity because of a rapid decrease and has excellent durability even when the gas contains moisture.
【０００４】[0004]
【発明が解決しようとする課題】本発明は、上述したよ
うな事情に鑑みてなされたものであつて、その目的とす
るところは、炭化水素を還元剤として用いる場合に、酸
素の共存下においても、そして、特に、酸素及び水分の
共存下においても、窒素酸化物が炭化水素と選択的に反
応するため、多量の還元剤を用いることなく、排ガス中
の窒素酸化物を効率よく還元することができ、しかも、
水分の存在下においても、耐久性にすぐれる窒素酸化物
接触還元用触媒を提供するにある。DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and has as its object to use a hydrocarbon as a reducing agent in the coexistence of oxygen. And, particularly, in the coexistence of oxygen and moisture, since nitrogen oxides selectively react with hydrocarbons, it is necessary to efficiently reduce nitrogen oxides in exhaust gas without using a large amount of a reducing agent. Can be done, and
An object of the present invention is to provide a catalyst for catalytic reduction of nitrogen oxides having excellent durability even in the presence of moisture.
【０００５】[0005]
【課題を解決するための手段】本発明による炭化水素を
還元剤として用いる窒素酸化物接触還元用触媒は、酸化
セリウム、酸化ランタン、酸化ネオジム、酸化ゲルマニ
ウム及び酸化ガリウムよりなる群から選ばれる少なくと
も１種の金属酸化物１００重量部に対して、白金、イリ
ジウム、ロジウム及びルテニウムよりなる群から選ばれ
る少なくとも１種0.１〜１００重量部からなる触媒がア
ルミナ、シリカ、シリカ−アルミナ、チタニア、ジルコ
ニア又はＨ型ゼオライトからなる担体に担持率５〜５０
重量％にて担体に担持されていることを特徴とする。According to the present invention, the catalyst for catalytic reduction of nitrogen oxides using a hydrocarbon as a reducing agent is at least one selected from the group consisting of cerium oxide, lanthanum oxide, neodymium oxide, germanium oxide and gallium oxide. A catalyst consisting of at least 0.1 to 100 parts by weight of at least one selected from the group consisting of platinum, iridium, rhodium and ruthenium is used per 100 parts by weight of the metal oxide.
Lumina, silica, silica-alumina, titania, zircon
Loading rate of carrier on near or H type zeolite 5-50
It is characterized in that it is supported on a carrier in a weight%.
【０００６】本発明による炭化水素を還元剤として用い
る窒素酸化物接触還元用触媒は、活性成分が、(a) 白
金、イリジウム、ロジウム及びルテニウムよりなる群
（以下、(a) 群元素ということがある。）から選ばれる
少なくとも１種と、(b) 酸化セリウム（ＣｅＯ2 ）、酸
化ランタン（Ｌａ2 Ｏ3 ）、酸化ネオジム（Ｎｄ2 Ｏ
3 ）、酸化ゲルマニウム（ＧｅＯ2 ）及び酸化ガリウム
（Ｇａ2 Ｏ3 ）よりなる群から選ばれる少なくとも１種
の金属酸化物とからなり、本発明によれば、更に、この
ような活性成分は、アルミナ、シリカ、シリカ−アルミ
ナ、チタニア、ジルコニア又はＨ型ゼオライトからなる
担体に担持されている。In the catalyst for catalytic reduction of nitrogen oxides using a hydrocarbon as a reducing agent according to the present invention, the active component is (a) a group consisting of platinum, iridium, rhodium and ruthenium (hereinafter referred to as the (a) group element). And (b) cerium oxide (CeO 2 ), lanthanum oxide (La 2 O 3 ), and neodymium oxide (Nd 2 O).
3 ), at least one metal oxide selected from the group consisting of germanium oxide (GeO 2 ) and gallium oxide (Ga 2 O 3 ). According to the present invention, such an active ingredient further comprises: Alumina, silica, silica-aluminum
Consists of na, titania, zirconia or H-type zeolite
Carried on a carrier .
【０００７】一般に、触媒の活性成分を担体に担持させ
る方法は、従来より種々知られており、本発明による触
媒は、その担持させる方法によつて何ら限定されるもの
ではなく、例えば、含浸法、沈着法、イオン交換法、又
はこれらの組み合わせ等によることができる。しかし、
本発明による触媒は、これらのなかでも、酸化セリウ
ム、酸化ランタン、酸化ネオジム、酸化ゲルマニウム及
び酸化ガリウムから選ばれる金属酸化物を含浸法や沈着
法によつて担体に担持させた後、イオン交換法によつて
白金、イリジウム、ロジウム及びルテニウムよりなる群
から選ばれる少なくとも１種を高分散担持させることに
よつて得るのが好ましい。更に、このようにして得られ
た触媒をこの後、水素等によつて還元処理することが好
ましい。In general, various methods for supporting an active component of a catalyst on a carrier have been conventionally known, and the catalyst according to the present invention is not limited at all by the method of supporting the catalyst. , Deposition, ion exchange, or a combination thereof. But,
The catalyst according to the present invention comprises, among these, a metal oxide selected from cerium oxide, lanthanum oxide, neodymium oxide, germanium oxide and gallium oxide supported on a carrier by impregnation or deposition, followed by ion exchange. Therefore, it is preferable to obtain by carrying at least one kind selected from the group consisting of platinum, iridium, rhodium and ruthenium in a highly dispersed state. Further, it is preferable that the catalyst thus obtained is thereafter subjected to a reduction treatment with hydrogen or the like.
【０００８】かかる方法によれば、高い活性と選択性を
有する窒素酸化物接触還元用触媒を得ることができる。
即ち、かかる方法によれば、予め形成された金属酸化物
のイオン交換基と白金錯体イオン、イリジウムイオン、
ロジウムイオン及びルテニウムイオンよりなる群から選
ばれる少なくとも１種のイオンがイオン交換し、これら
の酸化物上に高分散担持された白金等の(a) 群元素とこ
れら酸化物との相乗作用によつて、高い活性と選択性を
有する窒素酸化物接触還元用触媒を得ることができると
みられる。According to this method, a catalyst for catalytic reduction of nitrogen oxides having high activity and selectivity can be obtained.
That is, according to such a method, an ion exchange group of a metal oxide formed in advance and a platinum complex ion, an iridium ion,
At least one ion selected from the group consisting of rhodium ions and ruthenium ions is ion-exchanged, and a synergistic effect of these oxides with the (a) group element such as platinum, which is highly dispersed and supported on these oxides, is obtained. Thus, it is expected that a catalyst for catalytic reduction of nitrogen oxides having high activity and selectivity can be obtained.
【０００９】本発明による触媒において、白金等の(a)
群元素と前記金属酸化物との比率は、前記金属酸化物１
００重量部に対して、白金等の(a) 群元素が0.１〜１０
０重量部の範囲であり、好ましくは５〜５０重量部の範
囲である。このような比率を有する触媒によれば、いず
れかの成分が炭化水素の吸着活性化のサイトとして、又
は窒素酸化物の活性化サイトとして機能して、反応が選
択的に進行するので、炭化水素を還元剤として用いる窒
素酸化物の接触還元反応において、高い活性と選択性と
を有するものとみられる。In the catalyst according to the present invention, (a)
The ratio between the group element and the metal oxide is the same as that of the metal oxide 1
(A) group element such as platinum is 0.1 to 10 parts by weight with respect to 00 parts by weight.
It is in the range of 0 parts by weight, preferably in the range of 5 to 50 parts by weight. According to the catalyst having such a ratio, any one of the components functions as a site for activating adsorption of hydrocarbons or an activation site for nitrogen oxides, and the reaction proceeds selectively, so that hydrocarbons In a catalytic reduction reaction of nitrogen oxides using as a reducing agent, it is considered to have high activity and selectivity.
【００１０】更に、本発明によれば、かかる活性成分
は、５〜５０重量％の範囲の担持率にて担体に担持され
る。ここに、担持率とは、担体及び触媒の合計重量に対
する触媒の重量％をいう。本発明において、触媒活性成
分の担持率が５重量％よりも少ないときは、十分な触媒
活性を得ることができず、他方、担持率が５０重量％を
越えても、それに見合う触媒活性の増大を得ることがで
きない。Further, according to the present invention, the active ingredient is loaded on a carrier at a loading of 5 to 50% by weight.
You. Here, the loading ratio means the weight% of the catalyst with respect to the total weight of the carrier and the catalyst. In the present invention, when the loading of the catalytically active component is less than 5% by weight, sufficient catalytic activity cannot be obtained. On the other hand, even when the loading exceeds 50% by weight, a corresponding increase in the catalytic activity occurs. Can not get.
【００１１】本発明による触媒は、従来、知られている
成形方法によつて、ハニカム状、球状等の種々の形状に
成形することができる。この成形の際に、成形助剤、成
形体補強体、無機繊維、有機バインダー等を適宜配合し
てもよい。また、予め成形された基材上にウオツシユコ
ート法等によつて被覆担持させることもできる。更に、
従来、知られているその他の触媒の調製法によることも
できる。The catalyst according to the present invention can be formed into various shapes such as a honeycomb shape and a spherical shape by a conventionally known forming method. At the time of this molding, a molding aid, a molded body reinforcement, an inorganic fiber, an organic binder, and the like may be appropriately compounded. Further, it can be coated and supported on a preformed base material by a washcoat method or the like. Furthermore,
Conventionally known methods for preparing other catalysts can also be used.
【００１２】本発明による触媒を用いる窒素酸化物の接
触還元において、炭化水素からなる還元剤としては、例
えば、気体状のものとして、メタン、エタン、プロパ
ン、プロピレン、ブチレン等の炭化水素ガス、液体状の
ものとして、ペンタン、ヘキサン、オクタン、ヘプタ
ン、ベンゼン、トルエン、キシレン等の単一成分系の炭
化水素、ガソリン、灯油、軽油、重油等の鉱油系炭化水
素等を用いることができる。特に、本発明によれば、上
記したなかでも、アセチレン、メチルアセチレン、１−
ブチン等の低級アルキン、エチレン、プロピレン、イソ
ブチレン、１−ブテン、２−ブテン等の低級アルケン、
ブタジエン、イソプレン等の低級ジエン、プロパン、ブ
タン等の低級アルカン等が還元剤として好ましく用いら
れる。これら炭化水素は、単独で用いてもよく、又は必
要に応じて二種以上併用してもよい。In the catalytic reduction of nitrogen oxides using the catalyst according to the present invention, examples of the reducing agent comprising a hydrocarbon include gaseous ones such as hydrocarbon gas such as methane, ethane, propane, propylene and butylene; Examples of the shape include single-component hydrocarbons such as pentane, hexane, octane, heptane, benzene, toluene, and xylene, and mineral oil-based hydrocarbons such as gasoline, kerosene, light oil, and heavy oil. In particular, according to the present invention, among the above, acetylene, methylacetylene, 1-
Lower alkyne such as butyne, ethylene, propylene, isobutylene, 1-butene, lower alkene such as 2-butene,
Lower diene such as butadiene and isoprene and lower alkane such as propane and butane are preferably used as the reducing agent. These hydrocarbons may be used alone or in combination of two or more as needed.
【００１３】上記還元剤としての炭化水素は、用いる具
体的な炭化水素によつて異なるが、通常、窒素酸化物に
対するモル比にて、0.１〜２程度の範囲にて用いられ
る。炭化水素の使用量が窒素酸化物に対するモル比に
て、0.１未満であるときは、窒素酸化物に対して十分な
還元活性を得ることができず、他方、モル比が２を越え
るときは、未反応の炭化水素の排出量が多くなるため
に、窒素酸化物の接触還元処理の後に、これを回収する
ための後処理が必要となる。The hydrocarbon as the reducing agent varies depending on the specific hydrocarbon used, but is usually used in a molar ratio to nitrogen oxide of about 0.1 to about 2. When the amount of the hydrocarbon used is less than 0.1 in terms of the molar ratio to the nitrogen oxides, sufficient reduction activity for the nitrogen oxides cannot be obtained. On the other hand, when the molar ratio exceeds 2, Since a large amount of unreacted hydrocarbons is emitted, a post-treatment for recovering the nitrogen oxides after the catalytic reduction treatment of the nitrogen oxides is required.
【００１４】尚、排ガス中に存在する燃料等の未燃焼物
乃至不完全燃焼生成物、即ち、炭化水素類やパテイキユ
レート類等も還元剤として有効であり、これらも本発明
における炭化水素に含まれる。このことから、見方を変
えれば、本発明による触媒は、排ガス中の炭化水素類や
パテイキユレート類等の減少或いは除去触媒としても有
用であるということができる。[0014] Unburned or incomplete combustion products such as fuel present in the exhaust gas, ie, hydrocarbons and patitiurates are also effective as reducing agents, and these are also included in the hydrocarbons of the present invention. . From this point of view, it can be said that the catalyst according to the present invention is also useful as a catalyst for reducing or removing hydrocarbons and pateylates in exhaust gas.
【００１５】上記還元剤が窒素酸化物に対して選択的還
元反応を示す温度は、アルキン＜アルケン＜芳香族系炭
化水素＜アルカンの順に高くなる。また、同系の炭化水
素においては、炭素数が大きくなるに従つて、その温度
は低くなる。本発明による触媒が窒素酸化物に対して還
元活性を示す最適な温度は、使用する還元剤や触媒種に
より異なるが、通常、１００〜８００℃である。この温
度領域においては、空間速度（ＳＶ）５００〜１０００
００程度で排ガスを流通させることが好ましい。本発明
において特に好適な温度領域は２００〜４００℃であ
る。The temperature at which the reducing agent shows a selective reduction reaction with respect to nitrogen oxides increases in the order of alkyne <alkene <aromatic hydrocarbon <alkane. In addition, in hydrocarbons of the same system, the temperature decreases as the number of carbon atoms increases. The optimum temperature at which the catalyst according to the present invention exhibits a reducing activity on nitrogen oxides varies depending on the reducing agent and the type of catalyst used, but is usually from 100 to 800 ° C. In this temperature range, space velocity (SV) 500 to 1000
It is preferable that the exhaust gas is circulated at about 00. In the present invention, a particularly preferable temperature range is 200 to 400 ° C.
【００１６】[0016]
【実施例】以下に実施例を挙げて本発明を説明するが、
本発明はこれら実施例により何ら限定されるものではな
い。 （１）触媒の調製 実施例１ 硝酸セリウム（Ｃｅ（ＮＯ3)3 ・ ６Ｈ2 Ｏ）２8.５ｇを
イオン交換水１００mlに溶解させた。これに予め１２０
℃にて２４時間乾燥させた径３mmのγ−アルミナのペレ
ツト（住友化学製ＮＫ−３２４）１００ml（６０ｇ）を
投入し、３０分間放置して、上記硝酸セリウム溶液をγ
−アルミナの細孔内に十分に含浸させた。次いで、γ−
アルミナのペレツトを上記溶液から取出し、ペレツトの
表面に付着した過剰の上記溶液を除去した後、γ−アル
ミナのペレツトを６重量％のアンモニア水２００mlに投
入し、１時間放置して、γ−アルミナの細孔内で硝酸セ
リウムを中和加水分解させた。EXAMPLES The present invention will be described below with reference to examples.
The present invention is not limited by these examples. (1) Preparation Example of Catalyst 1 cerium nitrate (Ce (NO 3) 3 · 6H 2 O) and 28.5g was dissolved in deionized water 100 ml. 120
100 ml (60 g) of 3 mm diameter γ-alumina pellets (NK-324, manufactured by Sumitomo Chemical Co., Ltd.) dried at 24 ° C. for 24 hours and left for 30 minutes to remove the cerium nitrate solution from γ
-Fully impregnated into the pores of the alumina. Then, γ-
After removing the alumina pellet from the above solution and removing the excess solution adhering to the surface of the pellet, the pellet of γ-alumina was poured into 200 ml of 6% by weight aqueous ammonia, and left for 1 hour. Cerium nitrate was neutralized and hydrolyzed in the pores.
【００１７】次いで、このようにして得られたセリウム
イオンを担持させたγ−アルミナをイオン交換水で十分
に洗浄した後、５００℃で３時間焼成して、酸化セリウ
ムを担持率１０重量％にて担持させたγ−アルミナのペ
レツトを得た。この酸化セリウムを担持させたγ−アル
ミナのペレツトをイオン交換水２５０ml中に投入した。
このときのpHは7.１であつた。これに１／１０Ｎの硝酸
を加えて、pHを5.５とした。Next, the thus obtained γ-alumina supporting cerium ions is sufficiently washed with ion-exchanged water and calcined at 500 ° C. for 3 hours to reduce the cerium oxide loading to 10% by weight. Thus, a pellet of γ-alumina supported was obtained. The pellet of γ-alumina supporting cerium oxide was put into 250 ml of ion-exchanged water.
At this time, the pH was 7.1. 1 / 10N nitric acid was added thereto to adjust the pH to 5.5.
【００１８】別に、塩化テトラアンミン白金（II）
（〔Ｐｔ（ＮＨ3)4 〕Ｃｌ2 ・ Ｈ2 Ｏ）1.０８ｇをイオ
ン交換水５０mlに溶解させて、〔Ｐｔ（ＮＨ3)4 〕2+イ
オン交換水溶液を調製し、これを上記酸化セリウムを担
持させたγ−アルミナのペレツトを含む水溶液に十分な
攪拌下に加えて、〔Ｐｔ（ＮＨ3)4 〕2+とアルミナ又は
酸化セリウムにおける水素イオンとを交換させた。この
間、pHの低下に伴つて、２重量％のアンモニア水を加
え、pHを5.５に維持した。このようにして、所定の塩化
テトラアンミン白金（II）水溶液を加えた後、７０℃に
て２時間攪拌した。Separately, tetraammineplatinum (II) chloride
1.08 g of [[Pt (NH 3 ) 4 ] Cl 2 .H 2 O) was dissolved in 50 ml of ion-exchanged water to prepare an aqueous solution of [Pt (NH 3 ) 4 ] 2+ ion-exchange, which was then oxidized. [Pt (NH 3 ) 4 ] 2+ was exchanged with an aqueous solution containing a pellet of γ-alumina supporting cerium under sufficient stirring to exchange hydrogen ions in alumina or cerium oxide. During this period, 2% by weight of aqueous ammonia was added to keep the pH at 5.5 as the pH dropped. After adding a predetermined aqueous solution of tetraammineplatinum (II) chloride in this manner, the mixture was stirred at 70 ° C. for 2 hours.
【００１９】次いで、このようにしてイオン交換させた
酸化セリウム担持γ−アルミナペレツトを濾過し、pH5.
５の硝酸水溶液にて水洗し、１２０℃で１８時間乾燥さ
せた後、５００℃で４時間焼成し、更に、窒素／水素
（４／１）混合気流中、４００℃で１時間還元処理し
た。このようにして得られた触媒は、γ−アルミナに酸
化セリウム１０重量％、白金１重量％が担持されてなる
ものであつた。以下、この触媒をＡ−１という。Next, the cerium oxide-supported γ-alumina pellet thus ion-exchanged was filtered to obtain a pH 5.
5 was dried at 120 ° C. for 18 hours, calcined at 500 ° C. for 4 hours, and further reduced in a nitrogen / hydrogen (4/1) mixed gas stream at 400 ° C. for 1 hour. The catalyst thus obtained was obtained by supporting 10% by weight of cerium oxide and 1% by weight of platinum on γ-alumina. Hereinafter, this catalyst is referred to as A-1.
【００２０】実施例２ 硝酸セリウム（Ｃｅ（ＮＯ3)3 ・ ６Ｈ2 Ｏ）５7.０ｇを
イオン交換水１００mlに溶解させた。これに予め１２０
℃にて２４時間乾燥させた径３mmのγ−アルミナのペレ
ツト（住友化学製Ｎ４−３２４）１００ml（６０ｇ）を
投入し、３０分間放置して、上記硝酸セリウム溶液をγ
−アルミナの細孔内に十分に含浸させた。次いで、γ−
アルミナのペレツトを上記溶液から取出し、ペレツトの
表面に付着した過剰の上記溶液を除去した後、γ−アル
ミナのペレツトを６重量％のアンモニア水３００mlに投
入し、１時間放置して、γ−アルミナの細孔内で硝酸セ
リウムを中和加水分解させた。Example 2 57.0 g of cerium nitrate (Ce (NO 3 ) 3 .6H 2 O) was dissolved in 100 ml of ion-exchanged water. 120
100 ml (60 g) of a 3 mm diameter γ-alumina pellet (Sumitomo Chemical's N4-324) dried at 24 ° C. for 24 hours and left for 30 minutes to remove the cerium nitrate solution from γ
-Fully impregnated into the pores of the alumina. Then, γ-
After removing the alumina pellet from the above solution and removing the excess solution adhering to the surface of the pellet, the γ-alumina pellet was poured into 300 ml of 6% by weight ammonia water, and left for 1 hour. Cerium nitrate was neutralized and hydrolyzed in the pores.
【００２１】次いで、このようにして得られたセリウム
イオンを担持させたγ−アルミナをイオン交換水で十分
に洗浄した後、５００℃で３時間焼成して、酸化セリウ
ムを担持率２０重量％にて担持させたγ−アルミナのペ
レツトを得た。この酸化セリウムを担持させたγ−アル
ミナのペレツトをイオン交換水２５０ml中に投入した。
このときのpHは7.１であつた。これに１／１０Ｎの硝酸
を加えて、pHを5.５とした。Next, the thus obtained γ-alumina supporting cerium ions is sufficiently washed with ion-exchanged water and calcined at 500 ° C. for 3 hours to reduce the cerium oxide loading to 20% by weight. Thus, a pellet of γ-alumina supported was obtained. The pellet of γ-alumina supporting cerium oxide was put into 250 ml of ion-exchanged water.
At this time, the pH was 7.1. 1 / 10N nitric acid was added thereto to adjust the pH to 5.5.
【００２２】別に、塩化テトラアンミン白金（II）
（〔Ｐｔ（ＮＨ3)4 〕Ｃｌ2 ・ Ｈ2 Ｏ）1.０８ｇをイオ
ン交換水５０mlに溶解させて、〔Ｐｔ（ＮＨ3)4 〕2+イ
オン交換水溶液を調製し、これを上記酸化セリウムを担
持させたγ−アルミナのペレツトを含む水溶液に十分な
攪拌下に加えて、〔Ｐｔ（ＮＨ3)4 〕2+とアルミナ又は
酸化セリウムにおける水素イオンとを交換させた。この
間、pHの低下に伴つて、２重量％のアンモニア水を加
え、pHを5.５に維持した。このようにして、所定の塩化
テトラアンミン白金（II）水溶液を加えた後、７０℃に
て２時間攪拌した。この後、実施例１と同様にして、γ
−アルミナに酸化セリウム２０重量％、白金１重量％を
担持させた触媒をＡ−２を得た。Separately, tetraammineplatinum chloride (II)
1.08 g of [[Pt (NH 3 ) 4 ] Cl 2 .H 2 O) was dissolved in 50 ml of ion-exchanged water to prepare an aqueous solution of [Pt (NH 3 ) 4 ] 2+ ion-exchange, which was then oxidized. [Pt (NH 3 ) 4 ] 2+ was exchanged with an aqueous solution containing a pellet of γ-alumina supporting cerium under sufficient stirring to exchange hydrogen ions in alumina or cerium oxide. During this period, 2% by weight of aqueous ammonia was added to keep the pH at 5.5 as the pH dropped. After adding a predetermined aqueous solution of tetraammineplatinum (II) chloride in this manner, the mixture was stirred at 70 ° C. for 2 hours. Thereafter, in the same manner as in Example 1, γ
-A-2 was obtained as a catalyst in which cerium oxide (20% by weight) and platinum (1% by weight) were supported on alumina.
【００２３】実施例３ 硝酸セリウム（Ｃｅ（ＮＯ3)3 ・ ６Ｈ2 Ｏ）８5.５ｇを
イオン交換水１００mlに溶解させた。以下、実施例１と
同様にして、酸化セリウムを担持率３０重量％にて担持
させたγ−アルミナのペレツトを得た。この酸化セリウ
ムを担持させたγ−アルミナのペレツトをイオン交換水
２５０ml中に投入した。このときのpHは7.１であつた。
これに１／１０Ｎの硝酸を加えて、pHを5.５とした。Example 3 85.5 g of cerium nitrate (Ce (NO 3 ) 3 .6H 2 O) was dissolved in 100 ml of ion-exchanged water. Thereafter, in the same manner as in Example 1, a pellet of γ-alumina loaded with cerium oxide at a loading rate of 30% by weight was obtained. The pellet of γ-alumina supporting cerium oxide was put into 250 ml of ion-exchanged water. At this time, the pH was 7.1.
1 / 10N nitric acid was added thereto to adjust the pH to 5.5.
【００２４】別に、塩化テトラアンミン白金（II）
（〔Ｐｔ（ＮＨ3)4 〕Ｃｌ2 ・ Ｈ2 Ｏ）1.０８ｇをイオ
ン交換水５０mlに溶解させて、〔Ｐｔ（ＮＨ3)4 〕2+イ
オン交換水溶液を調製し、これを上記酸化セリウムを担
持させたγ−アルミナのペレツトを含む水溶液に十分な
攪拌下に加えて、〔Ｐｔ（ＮＨ3)4 〕2+とアルミナ又は
酸化セリウムにおける水素イオンとを交換させた。この
間、pHの低下に伴つて、２重量％のアンモニア水を加
え、pHを5.５に維持した。このようにして、所定の塩化
テトラアンミン白金（II）水溶液を加えた後、７０℃に
て２時間攪拌した。この後、実施例１と同様にして、γ
−アルミナに酸化セリウム３０重量％、白金１重量％を
担持させた触媒をＡ−３を得た。Separately, tetraammineplatinum chloride (II)
1.08 g of [[Pt (NH 3 ) 4 ] Cl 2 .H 2 O) was dissolved in 50 ml of ion-exchanged water to prepare an aqueous solution of [Pt (NH 3 ) 4 ] 2+ ion-exchange, which was then oxidized. [Pt (NH 3 ) 4 ] 2+ was exchanged with an aqueous solution containing a pellet of γ-alumina supporting cerium under sufficient stirring to exchange hydrogen ions in alumina or cerium oxide. During this period, 2% by weight of aqueous ammonia was added to keep the pH at 5.5 as the pH dropped. After adding a predetermined aqueous solution of tetraammineplatinum (II) chloride in this manner, the mixture was stirred at 70 ° C. for 2 hours. Thereafter, in the same manner as in Example 1, γ
-A-3 was obtained as a catalyst in which 30% by weight of cerium oxide and 1% by weight of platinum were supported on alumina.
【００２５】実施例４ 実施例３と同様にして、酸化セリウムを担持率３０重量
％にて担持させたγ−アルミナのペレツトを得た。別
に、塩化テトラアンミン白金（II）（〔Ｐｔ（Ｎ
Ｈ3)4 〕Ｃｌ2 ・ Ｈ2 Ｏ）2.１６ｇをイオン交換水１０
０mlに溶解させて、〔Ｐｔ（ＮＨ3)4 〕2+イオン交換水
溶液を調製し、これを上記酸化セリウムを担持させたγ
−アルミナのペレツトを含む水溶液に十分な攪拌下に加
えて、〔Ｐｔ（ＮＨ3)4 〕2+とアルミナ又は酸化セリウ
ムにおける水素イオンとを交換させた。この間、pHの低
下に伴つて、２重量％のアンモニア水を加え、pHを5.５
に維持した。このようにして、所定の塩化テトラアンミ
ン白金（II）水溶液を加えた後、７０℃にて２時間攪拌
した。この後、実施例１と同様にして、γ−アルミナに
酸化セリウム３０重量％、白金２重量％を担持させた触
媒をＡ−４を得た。Example 4 In the same manner as in Example 3, a pellet of γ-alumina loaded with cerium oxide at a loading of 30% by weight was obtained. Separately, tetraammineplatinum (II) chloride ([Pt (N
H 3 ) 4 ] Cl 2 .H 2 O) 2.16 g in deionized water 10
0 ml to prepare an aqueous solution of [Pt (NH 3 ) 4 ] 2+ ion exchange, which was loaded with γ on which cerium oxide was supported.
[Pt (NH 3 ) 4 ] 2+ was exchanged for hydrogen ions in alumina or cerium oxide by adding to an aqueous solution containing an alumina pellet with sufficient stirring. During this period, 2% by weight of aqueous ammonia was added to keep the pH at 5.5 as the pH dropped.
Maintained. After adding a predetermined aqueous solution of tetraammineplatinum (II) chloride in this manner, the mixture was stirred at 70 ° C. for 2 hours. Then, in the same manner as in Example 1, A-4 was obtained as a catalyst in which γ-alumina supported 30% by weight of cerium oxide and 2% by weight of platinum.
【００２６】実施例５ 実施例３と同様にして、酸化セリウムを担持率３０重量
％にて担持させたγ−アルミナのペレツトを得た。別
に、塩化テトラアンミン白金（II）（〔Ｐｔ（Ｎ
Ｈ3)4 〕Ｃｌ2 ・ Ｈ2 Ｏ）4.３２ｇをイオン交換水２０
０mlに溶解させて、〔Ｐｔ（ＮＨ3)4 〕2+イオン交換水
溶液を調製し、これを上記酸化セリウムを担持させたγ
−アルミナのペレツトを含む水溶液に十分な攪拌下に加
えて、〔Ｐｔ（ＮＨ3)4 〕2+とアルミナ又は酸化セリウ
ムにおける水素イオンとを交換させた。この間、pHの低
下に伴つて、２重量％のアンモニア水を加え、pHを5.５
に維持した。このようにして、所定の塩化テトラアンミ
ン白金（II）水溶液を加えた後、７０℃にて２時間攪拌
した。この後、実施例１と同様にして、γ−アルミナに
酸化セリウム３０重量％、白金４重量％を担持させた触
媒をＡ−５を得た。Example 5 In the same manner as in Example 3, a pellet of γ-alumina loaded with cerium oxide at a loading rate of 30% by weight was obtained. Separately, tetraammineplatinum (II) chloride ([Pt (N
H 3) 4] Cl 2 · H 2 O) 4.32g of deionized water 20
0 ml to prepare an aqueous solution of [Pt (NH 3 ) 4 ] 2+ ion exchange, which was loaded with γ on which cerium oxide was supported.
[Pt (NH 3 ) 4 ] 2+ was exchanged for hydrogen ions in alumina or cerium oxide by adding to an aqueous solution containing an alumina pellet with sufficient stirring. During this period, 2% by weight of aqueous ammonia was added to keep the pH at 5.5 as the pH dropped.
Maintained. After adding a predetermined aqueous solution of tetraammineplatinum (II) chloride in this manner, the mixture was stirred at 70 ° C. for 2 hours. Thereafter, in the same manner as in Example 1, A-5 was obtained as a catalyst having γ-alumina carrying 30% by weight of cerium oxide and 4% by weight of platinum.
【００２７】実施例６ 硝酸セリウム（Ｃｅ（ＮＯ3)3 ・ ６Ｈ2 Ｏ）８5.５ｇと
塩化白金酸（Ｈ2 ＰｔＣｌ6 ・ ６Ｈ2 Ｏ）1.５９ｇとを
イオン交換水に溶解させた。以下、実施例１と同様にし
て、γ−アルミナの細孔内でセリウム及び白金イオンを
中和加水分解させた。このようにして、セリウム及び白
金を担持させたγ−アルミナのペレツトをイオン交換水
にて十分に水洗した後、１２０℃で１８時間乾燥させ、
更に、５００℃で４時間焼成し、次に、窒素／水素（４
／１）混合気流中、４００℃で１時間還元処理した。か
くして、γ−アルミナに酸化セリウム３０重量％、白金
１重量％を担持させた触媒をＡ−６を得た。Example 6 85.5 g of cerium nitrate (Ce (NO 3 ) 3 .6H 2 O) and 1.59 g of chloroplatinic acid (H 2 PtCl 6 .6H 2 O) were dissolved in ion-exchanged water. Thereafter, in the same manner as in Example 1, cerium and platinum ions were neutralized and hydrolyzed in the pores of γ-alumina. Thus, the pellet of γ-alumina supporting cerium and platinum was sufficiently washed with ion-exchanged water, and then dried at 120 ° C. for 18 hours.
Further, calcination is performed at 500 ° C. for 4 hours, and then nitrogen / hydrogen (4
/ 1) Reduction treatment was performed at 400 ° C. for 1 hour in a mixed gas stream. Thus, A-6 was obtained as a catalyst in which γ-alumina supported 30% by weight of cerium oxide and 1% by weight of platinum.
【００２８】実施例７ 硝酸ランタン（Ｌａ（ＮＯ3)3 ・ ６Ｈ2 Ｏ）４7.８ｇを
イオン交換水１００mlに溶解させた。以下、実施例１と
同様にして、担持率３０重量％にて酸化ランタンを担持
させたγ−アルミナのペレツトを得た。これをイオン交
換水２５０ml中に投入した。このときのpHは7.３であつ
た。これに１／１０Ｎの硝酸を加えて、pHを5.５とし
た。以下、実施例４と同様にして、γ−アルミナに酸化
ランタン３０重量％、白金２重量％を担持させた触媒を
Ａ−７を得た。Example 7 47.8 g of lanthanum nitrate (La (NO 3 ) 3 .6H 2 O) was dissolved in 100 ml of ion-exchanged water. Thereafter, in the same manner as in Example 1, a γ-alumina pellet carrying lanthanum oxide at a loading ratio of 30% by weight was obtained. This was put into 250 ml of ion-exchanged water. The pH at this time was 7.3. 1 / 10N nitric acid was added thereto to adjust the pH to 5.5. Thereafter, in the same manner as in Example 4, a catalyst in which γ-alumina supported 30% by weight of lanthanum oxide and 2% by weight of platinum was obtained A-7.
【００２９】実施例８ 硝酸ネオジム（Ｎｄ（ＮＯ3)3 ・ ６Ｈ2 Ｏ）４6.９ｇを
イオン交換水１００mlに溶解させた。以下、実施例１と
同様にして、担持率３０重量％にて酸化ネオジムを担持
させたγ−アルミナのペレツトを得た。これをイオン交
換水２５０ml中に投入した。このときのpHは7.５であつ
た。これに１／１０Ｎの硝酸を加えて、pHを5.５とし
た。以下、実施例４と同様にして、γ−アルミナに酸化
ネオジム３０重量％、白金２重量％を担持させた触媒を
Ａ−８を得た。Example 8 46.9 g of neodymium nitrate (Nd (NO 3 ) 3 .6H 2 O) was dissolved in 100 ml of ion-exchanged water. Thereafter, in the same manner as in Example 1, a pellet of γ-alumina carrying neodymium oxide at a carrying ratio of 30% by weight was obtained. This was put into 250 ml of ion-exchanged water. The pH at this time was 7.5. 1 / 10N nitric acid was added thereto to adjust the pH to 5.5. Thereafter, in the same manner as in Example 4, A-8 was obtained as a catalyst in which 30% by weight of neodymium oxide and 2% by weight of platinum were supported on γ-alumina.
【００３０】実施例９ 実施例２と同様にして、酸化セリウムを担持率２０重量
％にて担持させたγ−アルミナのペレツトを得た。この
酸化セリウムを担持させたγ−アルミナのペレツトをイ
オン交換水２５０ml中に投入した。このときのpHは7.１
であつた。これに１／１０Ｎの硝酸を加えて、pHを3.０
とした。Example 9 In the same manner as in Example 2, a pellet of γ-alumina loaded with cerium oxide at a loading rate of 20% by weight was obtained. The pellet of γ-alumina supporting cerium oxide was put into 250 ml of ion-exchanged water. The pH at this time is 7.1
It was. To this, 1 / 10N nitric acid was added to adjust the pH to 3.0.
And
【００３１】別に、塩化ルテニウム（ＲｕＣｌ3 ）2.４
６ｇを0.１Ｎ塩酸に溶解させて、Ｒｕ3+イオン交換水溶
液を調製し、これを上記酸化セリウムを担持させたγ−
アルミナのペレツトを含む水溶液に十分な攪拌下に加え
て、Ｒｕ3+とアルミナ又は酸化セリウムにおける水素イ
オンとを交換させた。この間、pHの低下に伴つて、２重
量％のアンモニア水を加え、pHを3.０に維持した。この
ようにして、所定の塩化ルテニウムの塩酸水溶液を加え
た後、７０℃にて２時間攪拌した。この後、実施例１と
同様にして、γ−アルミナに酸化セリウム２０重量％、
ルテニウム２重量％を担持させた触媒をＡ−９を得た。Separately, ruthenium chloride (RuCl 3 ) 2.4
6 g was dissolved in 0.1N hydrochloric acid to prepare a Ru 3+ ion exchange aqueous solution, and this was mixed with the γ-
Ru 3+ was exchanged with hydrogen ions in alumina or cerium oxide by adding the aqueous solution containing the alumina pellet to the solution with sufficient stirring. During this period, 2% by weight of aqueous ammonia was added to keep the pH at 3.0 as the pH dropped. After adding a predetermined aqueous solution of ruthenium chloride in hydrochloric acid as described above, the mixture was stirred at 70 ° C. for 2 hours. Thereafter, in the same manner as in Example 1, γ-alumina contained 20% by weight of cerium oxide,
A-9 was obtained as a catalyst supporting 2% by weight of ruthenium.
【００３２】実施例１０ 硝酸ガリウム（Ｇａ（ＮＯ3)3 ・ ｎＨ2 Ｏ、Ｇａとして
１8.９重量％）５9.６ｇをイオン交換水１００mlに溶解
させた。これに予め１２０℃にて２４時間乾燥させた径
３mmのγ−アルミナのペレツト（住友化学製ＮＫ−３２
４）１００ml（６０ｇ）を投入し、３０分間放置して、
上記硝酸ガリウム溶液をγ−アルミナの細孔内に十分に
含浸させた。次いで、γ−アルミナのペレツトを上記溶
液から取出し、ペレツトの表面に付着した過剰の上記溶
液を除去した後、γ−アルミナのペレツトを６重量％の
アンモニア水２００mlに投入し、１時間放置して、γ−
アルミナの細孔内で硝酸ガリウムを中和加水分解させ
た。Example 10 59.6 g of gallium nitrate (Ga (NO 3 ) 3 .nH 2 O, 18.9% by weight as Ga) was dissolved in 100 ml of ion-exchanged water. A pellet of γ-alumina having a diameter of 3 mm previously dried at 120 ° C. for 24 hours (NK-32 manufactured by Sumitomo Chemical Co., Ltd.)
4) Add 100ml (60g), leave for 30 minutes,
The gallium nitrate solution was sufficiently impregnated into the pores of γ-alumina. Next, the pellet of γ-alumina was taken out of the above solution, and after removing the excess solution adhering to the surface of the pellet, the pellet of γ-alumina was poured into 200 ml of 6% by weight aqueous ammonia, and left for 1 hour. , Γ-
Gallium nitrate was neutralized and hydrolyzed in the pores of alumina.
【００３３】次いで、このようにして得られたガリウム
イオンを担持させたγ−アルミナをイオン交換水で十分
に洗浄した後、５００℃で３時間焼成して、酸化ガリウ
ムを担持率１０重量％にて担持させたγ−アルミナのペ
レツトを得た。この酸化ガリウムを担持させたγ−アル
ミナのペレツトをイオン交換水２５０ml中に投入した。
このときのpHは7.１であつた。これに１／１０Ｎの硝酸
を加えて、pHを5.５とした。Next, the gamma-alumina thus loaded with gallium ions is sufficiently washed with ion-exchanged water and calcined at 500 ° C. for 3 hours to reduce the gallium oxide loading to 10% by weight. Thus, a pellet of γ-alumina supported was obtained. The pellet of gamma-alumina supporting gallium oxide was put into 250 ml of ion-exchanged water.
At this time, the pH was 7.1. 1 / 10N nitric acid was added thereto to adjust the pH to 5.5.
【００３４】別に、塩化テトラアンミン白金（II）
（〔Ｐｔ（ＮＨ3)4 〕Ｃｌ2 ・ Ｈ2 Ｏ）1.０８ｇをイオ
ン交換水５０mlに溶解させて、〔Ｐｔ（ＮＨ3)4 〕2+イ
オン交換水溶液を調製し、これを上記酸化ガリウムを担
持させたγ−アルミナのペレツトを含む水溶液に十分な
攪拌下に加えて、〔Ｐｔ（ＮＨ3)4 〕2+とアルミナ又は
酸化ガリウムにおける水素イオンとを交換させた。この
間、pHの低下に伴つて、２重量％のアンモニア水を加
え、pHを5.５に維持した。このようにして、所定の塩化
テトラアンミン白金（II）水溶液を加えた後、７０℃に
て２時間攪拌した。Separately, tetraammineplatinum (II) chloride
1.08 g of [[Pt (NH 3 ) 4 ] Cl 2 .H 2 O) was dissolved in 50 ml of ion-exchanged water to prepare an aqueous solution of [Pt (NH 3 ) 4 ] 2+ ion-exchange, which was then oxidized. [Pt (NH 3 ) 4 ] 2+ was exchanged with an aqueous solution containing a pellet of γ-alumina supporting gallium under sufficient stirring to exchange hydrogen ions in alumina or gallium oxide. During this period, 2% by weight of aqueous ammonia was added to keep the pH at 5.5 as the pH dropped. After adding a predetermined aqueous solution of tetraammineplatinum (II) chloride in this manner, the mixture was stirred at 70 ° C. for 2 hours.
【００３５】次いで、このようにしてイオン交換させた
酸化ガリウム担持γ−アルミナペレツトを濾過し、pH5.
５の硝酸水溶液にて水洗し、１２０℃で１８時間乾燥さ
せた後、５００℃で４時間焼成し、更に、窒素／水素
（４／１）混合気流中、４００℃で１時間還元処理し
た。このようにして得られた触媒は、γ−アルミナに酸
化ガリウム１０重量％、白金１重量％が担持されてなる
ものであつた。以下、この触媒をＡ−１０という。Then, the gallium oxide-supported γ-alumina pellet thus ion-exchanged was filtered to obtain a pH 5.
5 was dried at 120 ° C. for 18 hours, calcined at 500 ° C. for 4 hours, and further reduced in a nitrogen / hydrogen (4/1) mixed gas stream at 400 ° C. for 1 hour. The catalyst thus obtained was obtained by supporting 10% by weight of gallium oxide and 1% by weight of platinum on γ-alumina. Hereinafter, this catalyst is referred to as A-10.
【００３６】実施例１１ 四塩化ゲルマニウム（ＧｅＣｌ4 ）５0.０ｇをエタノー
ル１０５mlに溶解させた。これに予め１２０℃にて２４
時間乾燥させた径３mmのγ−アルミナのペレツト（住友
化学製ＮＫ−３２４）１００ml（６０ｇ）を投入し、３
０分間乾燥デシケータ中に放置して、上記四塩化ゲルマ
ニウム溶液をγ−アルミナの細孔内に十分に含浸させ
た。Example 11 50.0 g of germanium tetrachloride (GeCl 4 ) was dissolved in 105 ml of ethanol. 24 hours at 120 ° C
100 ml (60 g) of a 3 mm diameter γ-alumina pellet (NK-324, manufactured by Sumitomo Chemical Co., Ltd.) dried for 3 hours was added.
It was left in a desiccator for 0 minutes to sufficiently impregnate the germanium tetrachloride solution into the pores of γ-alumina.
【００３７】以下、実施例１と同様にして、酸化ゲルマ
ニウムを担持率２０重量％にて担持させたγ−アルミナ
のペレツトを得た。この酸化ゲルマニウムを担持させた
γ−アルミナのペレツトをイオン交換水２５０ml中に投
入した。このときのpHは7.１であつた。これに１／１０
Ｎの硝酸を加えて、pHを5.５とした。Thereafter, in the same manner as in Example 1, a pellet of γ-alumina supporting germanium oxide at a supporting ratio of 20% by weight was obtained. The pellet of γ-alumina supporting germanium oxide was put into 250 ml of ion-exchanged water. At this time, the pH was 7.1. 1/10 to this
The pH was adjusted to 5.5 by adding N nitric acid.
【００３８】別に、塩化テトラアンミン白金（II）
（〔Ｐｔ（ＮＨ3)4 〕Ｃｌ2 ・ Ｈ2 Ｏ）1.０８ｇをイオ
ン交換水５０mlに溶解させて、〔Ｐｔ（ＮＨ3)4 〕2+イ
オン交換水溶液を調製し、これを上記酸化ゲルマニウム
を担持させたγ−アルミナのペレツトを含む水溶液に十
分な攪拌下に加えて、〔Ｐｔ（ＮＨ3)4 〕2+とアルミナ
又は酸化ゲルマニウムにおける水素イオンとを交換させ
た。この間、pHの低下に伴つて、２重量％のアンモニア
水を加え、pHを5.５に維持した。このようにして、所定
の塩化テトラアンミン白金（II）水溶液を加えた後、７
０℃にて２時間攪拌した。この後、実施例１と同様にし
て、γ−アルミナに酸化ゲルマニウム２０重量％、白金
１重量％を担持させた触媒をＡ−１１を得た。Separately, tetraammineplatinum (II) chloride
1.08 g of [[Pt (NH 3 ) 4 ] Cl 2 .H 2 O) was dissolved in 50 ml of ion-exchanged water to prepare an aqueous solution of [Pt (NH 3 ) 4 ] 2+ ion-exchange, which was then oxidized. [Pt (NH 3 ) 4 ] 2+ was exchanged for hydrogen ions in alumina or germanium oxide by adding to an aqueous solution containing a pellet of γ-alumina supporting germanium with sufficient stirring. During this period, 2% by weight of aqueous ammonia was added to keep the pH at 5.5 as the pH dropped. After adding a predetermined tetraammineplatinum (II) chloride aqueous solution in this manner, 7
Stirred at 0 ° C. for 2 hours. Thereafter, in the same manner as in Example 1, A-11 was obtained as a catalyst in which γ-alumina supported 20% by weight of germanium oxide and 1% by weight of platinum.
【００３９】実施例１２ 硝酸ランタン（Ｌａ（ＮＯ3)3 ・ ６Ｈ2 Ｏ）４7.８ｇを
イオン交換水１００mlに溶解させた。以下、実施例１と
同様にして、担持率３０重量％にて酸化ランタンを担持
させたγ−アルミナのペレツトを得た。この酸化ランタ
ンを担持させたγ−アルミナを８００℃にて５時間焼成
した。これをイオン交換水２５０ml中に投入した。この
ときのpHは7.５であつた。この後、実施例７と同様にし
て、γ−アルミナに酸化ランタン３０重量％、白金２重
量％を担持させた触媒をＡ−１２を得た。Example 12 47.8 g of lanthanum nitrate (La (NO 3 ) 3 .6H 2 O) was dissolved in 100 ml of ion-exchanged water. Thereafter, in the same manner as in Example 1, a γ-alumina pellet carrying lanthanum oxide at a loading ratio of 30% by weight was obtained. The γ-alumina supporting lanthanum oxide was calcined at 800 ° C. for 5 hours. This was put into 250 ml of ion-exchanged water. The pH at this time was 7.5. Thereafter, in the same manner as in Example 7, A-12 was obtained as a catalyst in which γ-alumina supported 30% by weight of lanthanum oxide and 2% by weight of platinum.
【００４０】実施例１３ 実施例１２と同様にして、酸化ランタンを担持させたγ
−アルミナのペレツト９８ｇを得た。塩化ロジウム（Ｒ
ｈＣｌ3 ・ ｎＨ2 Ｏ、Ｒｈとして３7.２４重量％）5.３
７ｇをイオン交換水５０mlに溶解させて、Ｒｈ3+イオン
交換水溶液を調製し、これを上記酸化ランタンを担持さ
せたγ−アルミナのペレツトを含む水溶液中に十分な攪
拌下に加えて、Ｒｈ3+イオンとアルミナ又は酸化ランタ
ンにおける水素イオンとをイオン交換させた。この間、
pHの低下に伴つて、２重量％のアンモニア水を加え、pH
を5.５に維持した。このようにして、所定の塩化ロジウ
ム水溶液を加えた後、７０℃にて２時間攪拌した。この
後、実施例１と同様にして、γ−アルミナに酸化ランタ
ン３０重量％、ロジウム２重量％を担持させた触媒をＡ
−１３を得た。Example 13 In the same manner as in Example 12, γ with lanthanum oxide
98 g of an alumina pellet were obtained. Rhodium chloride (R
hCl 3 .nH 2 O, 37.24% by weight as Rh) 5.3
7g was dissolved in ion-exchanged water 50 ml, and Rh 3+ ion exchange solution was prepared, which in addition to sufficient stirring in an aqueous solution containing Peretsuto of γ- alumina having supported thereon the oxide of lanthanum, Rh 3 + Ions were exchanged with hydrogen ions in alumina or lanthanum oxide. During this time,
With the decrease in pH, add 2% by weight of aqueous ammonia and adjust the pH.
Was maintained at 5.5. After adding the predetermined aqueous solution of rhodium chloride in this way, the mixture was stirred at 70 ° C. for 2 hours. Then, in the same manner as in Example 1, a catalyst in which γ-alumina supported 30% by weight of lanthanum oxide and 2% by weight of rhodium was used as A
-13 was obtained.
【００４１】実施例１４ 硝酸ガリウム（Ｇａ（ＮＯ3)3 ・ ｎＨ2 Ｏ、Ｇａとして
１8.９重量％）１1.８１ｇをイオン交換水１００mlに溶
解させた。Ｈ−モルデナイト（日本化学製ＨＭ−２３）
の径３mmのペレツト１００ml（７０ｇ）を含む温度７０
℃、pH2.５に調節したスラリー中に上記硝酸ガリウムの
水溶液を十分な攪拌下に加えて、イオン交換させた。こ
の間、pHの低下に伴つて、２重量％のアンモニア水を加
え、pHを2.５に維持した。このようにして、所定の硝酸
ガリウム水溶液を加えた後、２時間攪拌した。Example 14 11.81 g of gallium nitrate (Ga (NO 3 ) 3 .nH 2 O, 18.9% by weight as Ga) was dissolved in 100 ml of ion-exchanged water. H-mordenite (HM-23 manufactured by Nippon Chemical)
Containing 100 ml (70 g) of a 3 mm diameter pellet
The aqueous solution of gallium nitrate was added to the slurry adjusted to pH 2.5 and pH 2.5 under sufficient stirring to effect ion exchange. During this period, 2% by weight of aqueous ammonia was added to keep the pH at 2.5 as the pH dropped. After adding a predetermined gallium nitrate aqueous solution in this way, the mixture was stirred for 2 hours.
【００４２】次いで、このようにしてイオン交換させた
ガリウムイオン交換モルデナイトを濾過し、イオン交換
水にて洗浄し、１２０℃で１８時間乾燥させた後、７０
０℃にて５時間焼成した。このようにして、Ｇａイオン
５重量％を担持させたモルデナイトのペレツトを得た。
別に、塩化イリジウム（ＩｒＣｌ4 、塩化イリジウムと
して９8.９重量％）5.３２ｇを８０℃のイオン交換水１
００ml中に投入し、溶解させた。これに上記のモルデナ
イトのペレツトを投入し、３０分間放置して、モルデナ
イトの細孔内に十分に含浸させ、次いで、ペレツトを上
記溶液から取出し、ペレツトの表面に付着した過剰の水
溶液を除去した後、１０重量％のヒドラジン冷えにて還
元処理し、１２０℃で１８時間乾燥させた。これを５０
０℃にて３時間焼成して、イリジウム２重量％を担持さ
せたＧａイオン交換モルデナイト触媒Ａ−１４を得た。Next, the gallium ion-exchanged mordenite thus ion-exchanged was filtered, washed with ion-exchanged water, dried at 120 ° C. for 18 hours, and then dried.
It was baked at 0 ° C. for 5 hours. Thus, a mordenite pellet supporting 5% by weight of Ga ions was obtained.
Separately, 5.32 g of iridium chloride (IrCl 4 , 98.9% by weight as iridium chloride) was added to 80 ° C. deionized water 1
It was poured into 00 ml and dissolved. The mordenite pellet was put into the container and left for 30 minutes to sufficiently impregnate the pores of the mordenite. Then, the pellet was removed from the solution, and the excess aqueous solution attached to the surface of the pellet was removed. The mixture was reduced by cooling with 10% by weight of hydrazine, and dried at 120 ° C. for 18 hours. This is 50
The mixture was calcined at 0 ° C. for 3 hours to obtain a Ga ion exchange mordenite catalyst A-14 supporting 2% by weight of iridium.
【００４３】比較例１ 日本モービル社製のナトリウム型ＺＳＭ−５（ＳｉＯ2
／Ａｌ2 Ｏ3 モル比＝３４）を水素置換して、Ｈ型ＺＳ
Ｍ−５とし、これをシリカゾル（日産化学製スノーテツ
クスＮ）をバインダーとして用いて、直径2.４mmの球状
体に成形した。これを１２０℃で１８時間乾燥させた
後、５００℃で４時間焼成して、触媒Ｂ−１を得た。Comparative Example 1 A sodium type ZSM-5 (SiO 2 manufactured by Nippon Mobile Co., Ltd.)
/ Al 2 O 3 molar ratio = 34) by hydrogen substitution to form H-type ZS
M-5 was formed into a spherical body having a diameter of 2.4 mm using silica sol (Snowtex N manufactured by Nissan Chemical Industries, Ltd.) as a binder. This was dried at 120 ° C. for 18 hours and then calcined at 500 ° C. for 4 hours to obtain a catalyst B-1.
【００４４】比較例２ 塩化白金酸（Ｈ2 ＰｔＣｌ6 ・ ６Ｈ2 Ｏ）1.５９ｇをイ
オン交換水１００mlに溶解させた。これに実施例１と同
じγ−アルミナ１００mlを投入し、１時間放置した後、
γ−アルミナから過剰の溶液を除去した。次いで、γ−
アルミナを１２０℃で１８時間乾燥させた後、５００℃
で４時間焼成し、更に、窒素／水素（４／１）混合気流
中、４００℃で１時間還元処理した。かくして、γ−ア
ルミナに白金１重量％を担持させた触媒をＢ−２を得
た。[0044] Comparative Example 2 chloroplatinic acid (H 2 PtCl 6 · 6H 2 O) 1.59g was dissolved in deionized water 100 ml. 100 ml of the same γ-alumina as in Example 1 was added thereto, and left for 1 hour.
Excess solution was removed from γ-alumina. Then, γ-
After drying the alumina at 120 ° C. for 18 hours, 500 ° C.
For 4 hours, and further reduced at 400 ° C. for 1 hour in a mixed gas stream of nitrogen / hydrogen (4/1). Thus, B-2 was obtained as a catalyst in which 1% by weight of platinum was supported on γ-alumina.
【００４５】比較例３ 硝酸セリウム（Ｃｅ（ＮＯ3)3 ・ ６Ｈ2 Ｏ）８5.５ｇを
イオン交換水１００mlに溶解させた。以下、実施例１と
同様にして、γ−アルミナに酸化セリウム３０重量％を
担持させた触媒をＢ−３を得た。Comparative Example 3 85.5 g of cerium nitrate (Ce (NO 3 ) 3 .6H 2 O) was dissolved in 100 ml of ion-exchanged water. Thereafter, in the same manner as in Example 1, B-3 was obtained as a catalyst in which cerium oxide was supported on γ-alumina at 30% by weight.
【００４６】（２）評価試験 上記した本発明による触媒（Ａ−１〜１４）及び比較例
の触媒（Ｂ−１〜３）を用いて、下記の試験条件にて、
窒素酸化物含有ガスの窒素酸化物接触還元を行ない、窒
素酸化物の除去率をケミカルルミネツセンス法にて求め
た。 （試験条件） （１）ガス組成 ＮＯ ５００ ppm Ｏ2 １０容量％ 還元剤 ５００ ppm 水 ６容量％ 窒素 残部 （２）空間速度 １００００又は２００００（１／
Ｈｒ） （３）反応温度 ２００℃、２５０℃、３００℃、
３５０℃又は４００℃ 結果を表１に示す。(2) Evaluation Test Using the catalysts (A-1 to 14) according to the present invention and the catalysts (B-1 to 3) of the comparative examples under the following test conditions,
The nitrogen oxide-containing gas was subjected to nitrogen oxide catalytic reduction, and the removal rate of nitrogen oxide was determined by a chemical luminescence method. (Test conditions) (1) Gas composition NO 500 ppm O 2 10% by volume Reducing agent 500 ppm Water 6% by volume Nitrogen balance (2) Space velocity 10,000 or 20,000 (1 /
Hr) (3) Reaction temperature 200 ° C, 250 ° C, 300 ° C,
350 ° C. or 400 ° C. The results are shown in Table 1.
【００４７】[0047]
【表１】 [Table 1]
【００４８】表１に示す結果から明らかなように、本発
明による触媒は、いずれも窒素酸化物の窒素の除去率が
高いのに対して、比較例による触媒は、総じて、除去率
が低い。As is clear from the results shown in Table 1, the catalysts of the present invention all have a high nitrogen oxide removal rate, while the catalysts of the comparative examples generally have a low removal rate.
【００４９】[0049]
【発明の効果】以上のように、本発明による窒素酸化物
接触還元用触媒は、炭化水素を還元剤として用いて、酸
素及び水分の共存下においても、排ガス中の窒素酸化物
を効率よく接触還元することができ、更に、耐久性にす
ぐれる。As described above, the catalyst for catalytic reduction of nitrogen oxides according to the present invention uses hydrocarbons as a reducing agent to efficiently contact nitrogen oxides in exhaust gas even in the presence of oxygen and moisture. It can be reduced and has excellent durability.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 仲辻 忠夫 大阪府堺市戎島町５丁１番地 堺化学工 業株式会社 中央研究所内 (72)発明者 清水 宏益 大阪府堺市戎島町５丁１番地 堺化学工 業株式会社 中央研究所内 (72)発明者 安川 律 大阪府堺市戎島町５丁１番地 堺化学工 業株式会社 中央研究所内 (72)発明者 薄井 一司 千葉県野田市岩名１−62−10 (72)発明者 菅沼 藤夫 埼玉県北葛飾郡庄和町新宿新田228−16 (72)発明者 宮本 勝見 埼玉県北葛飾郡鷲宮町鷲宮１−11−17 (72)発明者 吉成 知博 埼玉県浦和市元町３−32−25 (72)発明者 金田一 嘉昭 茨城県つくば市東１−１ 工業技術院化 学技術研究所内 (72)発明者 佐々木 基 茨城県つくば市東１−１ 工業技術院化 学技術研究所内 審査官 野田 直人 (56)参考文献 特開 昭63−270543（ＪＰ，Ａ) 特開 昭52−116779（ＪＰ，Ａ) ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Tadao Nakatsuji 5-1-1 Ebisshima-cho, Sakai City, Osaka Prefecture Inside the Central Research Laboratory Sakai Chemical Industry Co., Ltd. (72) Hiromasa Shimizu 5-Ebishima Town, Sakai City, Osaka Prefecture No. 1 Sakai Chemical Industry Co., Ltd. Central Research Laboratory (72) Inventor Ritsu Yasukawa 5-1-1 Ebisshimacho, Sakai City, Osaka Prefecture Sakai Chemical Industry Co., Ltd. Central Research Laboratory (72) Inventor Kazushi Usui Iwa Noda City, Chiba Prefecture Name 1-62-10 (72) Inventor Fujio Suganuma 228-16 Shinjuku Nitta, Shinjuku, Showa-machi, Kita-Katsushika-gun, Saitama Prefecture (72) Inventor Katsumi Miyamoto 1-1-17, Washinomiya-cho, Washinomiya-cho, Kita-Katsushika-gun, Saitama (72) Inventor Yoshinari Yoshinari Tomohiro 3-32-25 Motomachi, Urawa-shi, Saitama (72) Inventor Yoshiaki Kaneda 1-1, Higashi, Tsukuba, Ibaraki Pref.Institute for Chemical Research, National Institute of Advanced Industrial Science and Technology (72) Motoi Sasaki 1-1, Higashi, Tsukuba, Ibaraki, Industrial Examiner, Naoto Noda, Institute of Chemical Technology, National Institute of Technology (56) Reference JP-A-63-270543 (JP, A) JP-A-52-116779 (JP, A)
Claims (3)
ム、酸化ゲルマニウム及び酸化ガリウムよりなる群から
選ばれる少なくとも１種の金属酸化物１００重量部に対
して、白金、イリジウム、ロジウム及びルテニウムより
なる群から選ばれる少なくとも１種0.１〜１００重量部
からなる触媒がアルミナ、シリカ、シリカ−アルミナ、
チタニア、ジルコニア又はＨ型ゼオライトからなる担体
に担持率５〜５０重量％にて担持されていることを特徴
とする炭化水素を還元剤として用いる窒素酸化物接触還
元用触媒。The present invention relates to at least one metal oxide selected from the group consisting of cerium oxide, lanthanum oxide, neodymium oxide, germanium oxide and gallium oxide, and 100 parts by weight of a metal oxide selected from the group consisting of platinum, iridium, rhodium and ruthenium. A catalyst comprising at least one selected from 0.1 to 100 parts by weight is alumina, silica, silica-alumina,
Carrier consisting of titania, zirconia or H-type zeolite
A catalyst for catalytic reduction of nitrogen oxides using a hydrocarbon as a reducing agent, wherein the catalyst is supported at a loading of 5 to 50% by weight.
交換法によつて、白金、イリジウム、ロジウム及びルテ
ニウムよりなる群から選ばれる少なくとも１種を更に担
持させてなる請求項１に記載の窒素酸化物接触還元用触
媒。 2. After the metal oxide is supported on the carrier, the ion
Platinum, iridium, rhodium and lute
At least one member selected from the group consisting of
2. The catalyst for catalytic reduction of nitrogen oxides according to claim 1, wherein
Medium.
に記載の窒素酸化物接触還元用触媒。3. A process according to claim 1 or 2 wherein the carrier is a γ- alumina
The catalyst for catalytic reduction of nitrogen oxides according to 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4288376A JP2618316B2 (en) | 1992-08-05 | 1992-10-27 | Catalyst for catalytic reduction of nitrogen oxides |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20923792 | 1992-08-05 | ||
| JP4-209237 | 1992-08-05 | ||
| JP4288376A JP2618316B2 (en) | 1992-08-05 | 1992-10-27 | Catalyst for catalytic reduction of nitrogen oxides |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0699068A JPH0699068A (en) | 1994-04-12 |
| JP2618316B2 true JP2618316B2 (en) | 1997-06-11 |
Family
ID=26517307
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4288376A Expired - Fee Related JP2618316B2 (en) | 1992-08-05 | 1992-10-27 | Catalyst for catalytic reduction of nitrogen oxides |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2618316B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7160839B2 (en) | 2001-01-11 | 2007-01-09 | Ict Co., Ltd. | Catalyst for purifying nitrogen oxides |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105200480A (en) * | 2015-10-30 | 2015-12-30 | 苏州莲池环保科技发展有限公司 | Preparation method of automobile exhaust catalyst |
| CN116493009B (en) * | 2023-06-15 | 2024-01-23 | 重庆市生态环境科学研究院 | Palladium-based pseudo-binary alloy catalyst and preparation method and application thereof |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1581628A (en) * | 1976-03-18 | 1980-12-17 | Johnson Matthey Co Ltd | Catalytic purification of automobile exhaust gases |
| US4839146A (en) * | 1987-04-15 | 1989-06-13 | General Motors Corporation | Catalyst for simultaneous NO decomposition and CO oxidation under cycled operating conditions |
-
1992
- 1992-10-27 JP JP4288376A patent/JP2618316B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7160839B2 (en) | 2001-01-11 | 2007-01-09 | Ict Co., Ltd. | Catalyst for purifying nitrogen oxides |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0699068A (en) | 1994-04-12 |
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