JPH0640958B2 - Method for producing silica catalyst supporting platinum group metal - Google Patents
Method for producing silica catalyst supporting platinum group metalInfo
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- JPH0640958B2 JPH0640958B2 JP23887887A JP23887887A JPH0640958B2 JP H0640958 B2 JPH0640958 B2 JP H0640958B2 JP 23887887 A JP23887887 A JP 23887887A JP 23887887 A JP23887887 A JP 23887887A JP H0640958 B2 JPH0640958 B2 JP H0640958B2
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- platinum group
- group metal
- silica
- catalyst
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Description
【発明の詳細な説明】 イ．発明の目的 産業上の利用分野 本発明は白金族金属が高分散し且つアミノ基を含有する
活性の高いシリカ触媒を製造する方法に関するものであ
る。Detailed Description of the Invention a. OBJECT OF THE INVENTION Industrial Field of the Invention The present invention relates to a method for producing a highly active silica catalyst in which a platinum group metal is highly dispersed and contains an amino group.
従来の技術 シリカはアルミナとは異なり、ＰｔＣｌ６…、ＰｄＣｌ
４…などの白金族金属イオンとの反応性が無いため、高
分散の白金族金属担持シリカ触媒を調製することは難し
い。Prior Art Silica is different from alumina in that PtCl 6 ..., PdCl
It is difficult to prepare a highly dispersed platinum group metal-supported silica catalyst because it has no reactivity with platinum group metal ions such as 4 ...
多孔性ガラスをアミノ基を有するシラン化合物で処理し
次いで塩化パラジウム溶液を含浸させ洗浄後風乾したも
のは良好な触媒活性を示すこと、またこれを還元性雰囲
気気流中５００℃で焼成したものは非常に良く水素を吸
着するとされている（特開昭61-97146）。Those obtained by treating the porous glass with a silane compound having an amino group, impregnating it with a palladium chloride solution, washing it, and air-drying it showed good catalytic activity, and burning it at 500 ° C. in a reducing atmosphere was very It is said that it adsorbs hydrogen well (JP-A-61-97146).
しかしシリカ担体について上記方法を適用した場合、白
金族金属の分散が悪く、その水素吸着能はまだ十分とは
言えない。However, when the above method is applied to a silica carrier, the platinum group metal is poorly dispersed, and its hydrogen adsorption capacity is not yet sufficient.
発明が解決しようとする問題点 本発明は白金族金属が高分散し水素吸着能が高く、且つ
これを液相反応触媒として用いる場合、含有するアミノ
基により反応系のｐＨをあまり低下しないようにコント
ロールできるシリカ触媒を技術的に容易に、再現性良く
製造できる方法を提供することを目的とする。DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention In the present invention, a platinum group metal is highly dispersed and has a high hydrogen adsorption capacity, and when it is used as a liquid phase reaction catalyst, the pH of the reaction system is not lowered so much by the contained amino groups. It is an object of the present invention to provide a method capable of producing a controllable silica catalyst technically easily and with good reproducibility.
ロ．発明の構成 問題点を解決するための手段 本発明の白金族金属担持シリカ触媒の製造方法は、シリ
カ担体をアミノ基を有するシラン化合物と接触させて改
質し、ついで白金族金属塩の水溶液と接触させて白金族
金属イオンとアミノ基との錯体をシリカ担体上に形成さ
せた後、２５０℃〜４５０℃の温度範囲で気相還元する
ことを特徴とする。B. Means for Solving the Problems The method for producing a platinum group metal-supported silica catalyst according to the present invention comprises modifying a silica support by bringing it into contact with a silane compound having an amino group, and then adding an aqueous solution of a platinum group metal salt. It is characterized in that a complex of a platinum group metal ion and an amino group is formed on the silica support by bringing them into contact with each other, and then vapor phase reduction is carried out in a temperature range of 250 ° C to 450 ° C.
本発明の白金族金属担持シリカ触媒の製造法は次の３工
程からなる。The process for producing the platinum group metal-supported silica catalyst of the present invention comprises the following three steps.
シリカ担体を有機アミノ基を有するシラン化合物で改
質することによりアニオン交換性をもたせる。By modifying the silica carrier with a silane compound having an organic amino group, anion exchange property is provided.
上記改質シリカ担体を白金族金属塩の水溶液と接触さ
せることにより、白金族金属イオンは有機アミノ基との
錯体を形成し担体に固定される。By contacting the modified silica carrier with an aqueous solution of a platinum group metal salt, the platinum group metal ion forms a complex with an organic amino group and is fixed to the carrier.
固定化錯体を２５０℃〜４５０℃の温度範囲で気相還
元して、白金族金属担持シリカ触媒とする。The immobilized complex is vapor-phase reduced in the temperature range of 250 ° C. to 450 ° C. to obtain a platinum group metal-supported silica catalyst.
以下詳細に説明すると、まずシリカ担体と、３−アミノ
プロピルトリアルコキシシラン又はＮ−（２−アミノエ
チル）−３−アミノプロピルトリアルコキシシランなど
のアミノ基を有するシラン化合物とを純水又はトルエン
等の溶媒中で接触させるか、又はシリカ担体にアミノ基
を有するシラン化合物を含浸すると、シリカのシラノー
ル基とアミノ基を有するシラン化合物は反応してシリカ
担体は改質される。Explaining in detail below, first, a silica carrier and a silane compound having an amino group such as 3-aminopropyltrialkoxysilane or N- (2-aminoethyl) -3-aminopropyltrialkoxysilane are purified water or toluene. When the silica carrier is contacted in the solvent or the silica carrier is impregnated with a silane compound having an amino group, the silanol group of silica and the silane compound having an amino group react with each other to modify the silica carrier.
改質シリカの有機アミノ基量はシラン化合物の仕込量に
よりコントロールする。The amount of organic amino groups in the modified silica is controlled by the amount of silane compound charged.
改質シリカの有機アミノ基量は目標とする白金族金属の
担持量に応じて定めればよいが、０．１〜１０重量％の
白金族金属を担持するのに必要な改質シリカ１ｇあたり
のアミノ基量は０．１〜２．０ミリモル程度である。The amount of the organic amino group of the modified silica may be determined according to the target amount of the platinum group metal supported, but per 1 g of the modified silica required to support 0.1 to 10% by weight of the platinum group metal. The amount of amino groups is about 0.1 to 2.0 mmol.
この改質シリカは導入された有機アミノ基によりイオン
交換する能力を有するようになる。This modified silica comes to have the ability to be ion-exchanged by the introduced organic amino group.
ついで白金族金属塩の水溶液と上記改質シリカ担体を接
触させると、白金族金属イオンがイオン交換され有機ア
ミノ基との間で錯体を形成しシリカ担体上に固定され
る。このため白金族金属の分散性は良く、また溶液中の
大部分の白金族金属イオンが固定化されるため白金族金
属のロスを低減できる。Next, when the aqueous solution of the platinum group metal salt is brought into contact with the modified silica carrier, the platinum group metal ions are ion-exchanged to form a complex with the organic amino group and are fixed on the silica carrier. Therefore, the dispersibility of the platinum group metal is good, and most of the platinum group metal ions in the solution are fixed, so that the loss of the platinum group metal can be reduced.
担持できる白金族金属としてはＰｔ、Ｐｄ、Ｒｕ、Ｒｈ
などが挙げられる。原料としては塩化物、硝酸塩、硫酸
塩などが挙げられるが、価格の点を考えると塩化物が適
している。Platinum group metals that can be supported include Pt, Pd, Ru, and Rh.
And so on. As the raw material, chloride, nitrate, sulfate and the like can be mentioned, but chloride is suitable in view of price.
気相還元はＨ２、ＣＯなどの気流中で行う通常の方法で
行うことができる。但し２５０℃〜４５０℃の温度範囲
で行うことが必要で、それ以下では十分に還元を行うこ
とができない。また４５０℃以上になるとアミノ基の分
解が進行すると共にかえって白金族金属の分散が悪くな
り、Ｈ２吸着能が低下する。The gas phase reduction can be carried out by a usual method carried out in a stream of H 2 , CO or the like. However, it is necessary to carry out in the temperature range of 250 ° C to 450 ° C, and if it is lower than that, sufficient reduction cannot be carried out. At 450 ° C. or higher, the decomposition of the amino group progresses and the dispersion of the platinum group metal deteriorates, and the H 2 adsorption capacity decreases.
実施例１，２及び比較例１，２（Ｐｄ担持触媒） 有機アミノ基量が０．６ミリモル／ｇシリカとなる量の
３−アミノプロピルトリエトキシシランを純水に溶解し
たものに、シリカ担体２００ｇを加えて攪拌したのち濾
過水洗し、１１０℃で乾燥して改質シリカを得た。Examples 1 and 2 and Comparative Examples 1 and 2 (Pd-supported catalyst) A silica carrier was prepared by dissolving 3-aminopropyltriethoxysilane in an amount such that the amount of organic amino groups was 0.6 mmol / g silica in pure water. After adding 200 g and stirring, it was filtered, washed with water and dried at 110 ° C. to obtain modified silica.
改質シリカ５０ｇに対してパラジウム含有量が２重量％
になる量の塩化パラジウム溶液を加え塩化パラジウムと
有機アミノ基との錯体をシリカ担体上に形成させ、溶液
を濾過したのち１１０℃で乾燥して錯体固定化シリカを
得た。この時溶液中に残ったパラジウム量は仕込量の
０．０１％であった。Palladium content is 2% by weight to 50 g of modified silica
Was added to form a complex of palladium chloride and an organic amino group on a silica carrier, and the solution was filtered and dried at 110 ° C. to obtain complex-immobilized silica. At this time, the amount of palladium remaining in the solution was 0.01% of the charged amount.
錯体固定シリカをＨ２気流中で２００℃、３００℃、４
００℃及び５００℃の各温度で還元して触媒Ａ（比較例
１）、Ｂ（実施例１）、Ｃ（実施例２）及びＤ（比較例
２）を得た。200 ° C. The complex fixed silica with H 2 gas stream, 300 ° C., 4
The catalysts A (Comparative Example 1), B (Example 1), C (Example 2) and D (Comparative Example 2) were obtained by reduction at respective temperatures of 00 ° C and 500 ° C.
比較例３（従来のＰｄ／ＳｉＯ２触媒） シリカ担体３０ｇにパラジウム含有量が２重量％になる
量の塩化パラジウム溶液を加え加熱攪拌しながら蒸発乾
固した。その後Ｈ２気流中３００℃で還元して触媒Ｅを
得た。Comparative Example 3 (Conventional Pd / SiO 2 catalyst) To 30 g of a silica carrier was added a palladium chloride solution in an amount such that the palladium content was 2% by weight, and the mixture was evaporated to dryness with heating and stirring. After that, the catalyst E was obtained by reducing at 300 ° C. in an H 2 stream.
以上のようにして調製した触媒Ａ〜Ｅの白金族金属含有
量、有機アミノ基量、Ｈ２吸着量及び分散度ならびにＨ
２Ｏ２分解反応活性を第１表に示す。The platinum group metal content, the amount of organic amino groups, the amount of H 2 adsorbed and the degree of dispersion, and H of the catalysts A to E prepared as described above
2 O 2 decomposition reaction activity is shown in Table 1.
このＨ２Ｏ２分解反応活性は、０．５モル／のＨ２Ｏ
２溶液２００mlに室温で触媒をＰｄとして約４mg加え、
各時間におけるＨ２Ｏ２残存量を過マンガン酸カリの滴
定により求めた。また白金族金属分散度はＨ２吸着量か
ら白金族金属原子１個にＨ原子１個が吸着すると仮定し
て求めた。 This H 2 O 2 decomposition reaction activity is 0.5 mol / H 2 O.
At room temperature, add about 4 mg of catalyst as Pd to 200 ml of 2 solution,
The residual amount of H 2 O 2 at each time was determined by titration with potassium permanganate. The platinum group metal dispersity was calculated from the amount of H 2 adsorption assuming that one H atom is adsorbed on each platinum group metal atom.
また触媒Ａ〜Ｅについて、還元温度とＨ２吸着量との関
係を第１図に、還元温度と白金族金属の分散度との関係
を第２図に、還元温度とＨ２Ｏ２分解反応活性との関係
を第３図に示した。Regarding the catalysts A to E, the relationship between the reduction temperature and the H 2 adsorption amount is shown in FIG. 1, the relationship between the reduction temperature and the dispersity of the platinum group metal is shown in FIG. 2, the reduction temperature and the H 2 O 2 decomposition reaction. The relationship with activity is shown in FIG.
第１表のデータ及び第１図〜第３図より、シリカ担体を
アミノ基を有するシラン化合物と接触させて改質し、つ
いで白金族金属塩の水溶液と接触させて白金族金属イオ
ンとアミノ基との錯体をシリカ担体上に形成させた後、
２５０℃〜４５０℃の温度範囲で水素ガスと接触させて
還元処理して得られる触媒は、２００℃又は５００℃で
水素ガスと接触させて還元処理して得られる触媒、ある
いはアミノ基を有するシラン化合物によるシリカ担体の
改質を行っていない触媒に比し、Ｈ２吸着量、白金族金
属の分散度、Ｈ２Ｏ２分解反応活性が優れていることが
わかる。From the data of Table 1 and FIGS. 1 to 3, the silica carrier was contacted with a silane compound having an amino group to be modified, and then contacted with an aqueous solution of a platinum group metal salt to obtain a platinum group metal ion and an amino group. After forming a complex with and on a silica support,
The catalyst obtained by contacting with hydrogen gas in a temperature range of 250 ° C. to 450 ° C. and reducing treatment is a catalyst obtained by contacting with hydrogen gas at 200 ° C. or 500 ° C. and reducing treatment, or a silane having an amino group. It can be seen that the H 2 adsorption amount, the degree of dispersion of the platinum group metal, and the H 2 O 2 decomposition reaction activity are superior to those of the catalyst in which the silica support is not modified with the compound.
実施例３（Ｒｕ担持触媒） 実施例１で得た改質シリカ３０ｇに対しルテニウム含有
量が２重量％となる量の塩化ルテニウム溶液を加えたの
ち実施例１と同様の操作を行い錯体固定シリカを得た。
その後Ｈ２気流中４００℃で還元して触媒Ｆを得た。Example 3 (Ru-supported catalyst) To 30 g of the modified silica obtained in Example 1, a ruthenium chloride solution having an amount of ruthenium content of 2% by weight was added, and the same operation as in Example 1 was carried out. Got
After that, the catalyst F was obtained by reducing at 400 ° C. in an H 2 stream.
この触媒の有機アミノ基残量は０．４５ミリモル／ｇ
（残存率７５％）、Ｈ２吸着量は６５．３μモル／ｇ、
分散度０．６６であった。The residual amount of organic amino groups in this catalyst is 0.45 mmol / g
(Residual rate 75%), H 2 adsorption amount is 65.3 μmol / g,
The dispersity was 0.66.
実施例４（Ｒｕ担持触媒） 実施例１で得た改質シリカ３０ｇに対しロジウム含有量
が２重量％となる量の塩化ロジウム溶液を加えたのち実
施例１と同様の操作を行い錯体固定シリカを得た。その
後Ｈ２気流中４００℃で還元して触媒Ｇを得た。Example 4 (Ru-supported catalyst) To 30 g of the modified silica obtained in Example 1, a rhodium chloride solution was added in an amount such that the rhodium content was 2% by weight, and then the same procedure as in Example 1 was carried out to carry out complex-fixed silica. Got Then, the catalyst G was obtained by reducing at 400 ° C. in an H 2 stream.
この触媒の有機アミノ基残量は０．４１ミリモル／ｇ
（残存率６８％）、Ｈ２吸着量は６８．０μモル／ｇ、
分散度０．７０であった。The residual amount of organic amino groups in this catalyst is 0.41 mmol / g
(Residual rate 68%), H 2 adsorption amount is 68.0 μmol / g,
The dispersity was 0.70.
実施例５（Ｐｔ担持触媒） 有機アミノ基量が０．３ミリモル／ｇとなる量の３−ア
ミノプロピルトリエトキシシランを純水に溶解したもの
に、シリカ担体２００ｇを加えたのち実施例１と同様の
操作を行い改質シリカを得た。Example 5 (Pt-supported catalyst) 200 g of a silica carrier was added to a solution prepared by dissolving 3-aminopropyltriethoxysilane in an amount such that the amount of organic amino groups was 0.3 mmol / g in pure water, and then Example 1 was used. The same operation was performed to obtain modified silica.
改質シリカ３０ｇに対して白金含有量が２重量％になる
量の塩化白金酸溶液を加えたのち実施例１と同様の操作
を行い錯体固定シリカを得た。After adding a chloroplatinic acid solution in such an amount that the platinum content becomes 2% by weight with respect to 30 g of the modified silica, the same operation as in Example 1 was carried out to obtain a complex-fixed silica.
その後Ｈ２気流中４００℃で還元して触媒Ｈを得た。After that, the catalyst H was obtained by reducing at 400 ° C. in an H 2 stream.
この触媒の有機アミノ基残量は０．２ミリモル／ｇ（残
存率６７％）、Ｈ２吸着量は３０．８μモル／ｇ、分散
度０．６０であった。The residual amount of organic amino groups of this catalyst was 0.2 mmol / g (residual ratio 67%), the H 2 adsorption amount was 30.8 μmol / g, and the dispersity was 0.60.
ハ．発明の効果 シリカは白金族金属イオンを吸着しないため分散性の
低下ならびに担持ムラが生じやすいが、本発明方法によ
ると担持量が１０％位までの高範囲において再現性よく
均一に担持し、しかも白金族金属の分散性をよくするこ
とができる。C. EFFECTS OF THE INVENTION Silica does not adsorb platinum group metal ions, so that the dispersibility tends to decrease and the loading unevenness tends to occur. However, according to the method of the present invention, the loading is carried out uniformly in a high range up to about 10%, and moreover, The dispersibility of the platinum group metal can be improved.
白金族金属粒子は分散性がよく、熱によるシンタリン
グも少ない。したがって広い温度範囲での使用が可能で
ある。Platinum group metal particles have good dispersibility and little sintering due to heat. Therefore, it can be used in a wide temperature range.
有機溶媒に対する耐性が優れているため非水溶媒での
触媒として有効である。Since it has excellent resistance to organic solvents, it is effective as a catalyst in non-aqueous solvents.
反応系のｐＨをコントロールした方が有効に反応が進
む場合、例えば過酸化水素の分解反応等においてはｐＨ
の高い方が反応が速い。この様な場合、本触媒は有機ア
ミノ基により溶液のｐＨを上げるため反応を有利に進め
ることができる。If the reaction proceeds effectively by controlling the pH of the reaction system, for example, in the decomposition reaction of hydrogen peroxide,
The higher the value, the faster the reaction. In such a case, the present catalyst can advance the reaction advantageously because the pH of the solution is raised by the organic amino group.
溶液中の白金族金属イオンは全量有機アミノ基と反応
し錯体を形成しシリカ上に固定されているため白金族金
属のロスを低減できる。The platinum group metal ions in the solution all react with organic amino groups to form a complex and are fixed on silica, so that the loss of platinum group metal can be reduced.
第１図は触媒の気相還元温度とＨ２吸着量との関係を示
す図、第２図は触媒の気相還元温度と白金族金属の分散
度との関係を示す図、第３図は触媒の気相還元温度とＨ
２Ｏ２分解反応活性との関係を示す図である。FIG. 1 is a diagram showing the relationship between the gas phase reduction temperature of the catalyst and the H 2 adsorption amount, FIG. 2 is a diagram showing the relationship between the gas phase reduction temperature of the catalyst and the degree of dispersion of the platinum group metal, and FIG. 3 is Gas phase reduction temperature of catalyst and H
It is a diagram showing a relationship between 2 O 2 decomposition reaction activity.
Claims (1)
物と接触させて改質し、ついで白金族金属塩の水溶液と
接触させて白金族金属イオンとアミノ基との錯体をシリ
カ担体上に形成させた後、２５０℃〜４５０℃の温度範
囲で気相還元することを特徴とする白金族金属担持シリ
カ触媒の製造方法。1. A silica carrier is contacted with a silane compound having an amino group for modification, and then contacted with an aqueous solution of a platinum group metal salt to form a complex of a platinum group metal ion and an amino group on the silica carrier. And a gas phase reduction in a temperature range of 250 ° C. to 450 ° C., a method for producing a platinum group metal-supported silica catalyst.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23887887A JPH0640958B2 (en) | 1987-09-25 | 1987-09-25 | Method for producing silica catalyst supporting platinum group metal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23887887A JPH0640958B2 (en) | 1987-09-25 | 1987-09-25 | Method for producing silica catalyst supporting platinum group metal |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6485140A JPS6485140A (en) | 1989-03-30 |
| JPH0640958B2 true JPH0640958B2 (en) | 1994-06-01 |
Family
ID=17036608
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP23887887A Expired - Lifetime JPH0640958B2 (en) | 1987-09-25 | 1987-09-25 | Method for producing silica catalyst supporting platinum group metal |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0640958B2 (en) |
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| WO2021105065A1 (en) | 2019-11-29 | 2021-06-03 | Saes Getters S.P.A. | Food package for amines control or removal |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5196267A (en) * | 1991-06-21 | 1993-03-23 | Allied-Signal Inc. | Process for coating silica spheres |
| JP2882917B2 (en) * | 1991-09-20 | 1999-04-19 | 株式会社日立製作所 | Toxic-resistant catalyst for combustible gas combustion, method for producing the same and method of using the catalyst |
| JP4822461B2 (en) * | 2008-10-30 | 2011-11-24 | 独立行政法人産業技術総合研究所 | Method for continuous decomposition of hydrogen peroxide |
| JP6314411B2 (en) * | 2013-10-10 | 2018-04-25 | 三菱瓦斯化学株式会社 | Hydrogenation catalyst for aromatic carboxylic acids and process for producing the same |
-
1987
- 1987-09-25 JP JP23887887A patent/JPH0640958B2/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1992000828A1 (en) * | 1990-07-12 | 1992-01-23 | Nippondenso Co., Ltd. | Method of welding metals of different kind by laser |
| WO2021105065A1 (en) | 2019-11-29 | 2021-06-03 | Saes Getters S.P.A. | Food package for amines control or removal |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6485140A (en) | 1989-03-30 |
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