JPS5926335B2 - Platinum group oxidation catalyst and its manufacturing method - Google Patents
Platinum group oxidation catalyst and its manufacturing methodInfo
- Publication number
- JPS5926335B2 JPS5926335B2 JP53010558A JP1055878A JPS5926335B2 JP S5926335 B2 JPS5926335 B2 JP S5926335B2 JP 53010558 A JP53010558 A JP 53010558A JP 1055878 A JP1055878 A JP 1055878A JP S5926335 B2 JPS5926335 B2 JP S5926335B2
- Authority
- JP
- Japan
- Prior art keywords
- catalyst
- palladium
- carrier
- approximately
- less
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 239000003054 catalyst Substances 0.000 title claims description 123
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical group [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 title claims description 31
- 230000003647 oxidation Effects 0.000 title claims description 7
- 238000007254 oxidation reaction Methods 0.000 title claims description 7
- 238000004519 manufacturing process Methods 0.000 title claims description 6
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 claims description 52
- 239000011148 porous material Substances 0.000 claims description 42
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 38
- 229910052763 palladium Inorganic materials 0.000 claims description 26
- 239000000243 solution Substances 0.000 claims description 23
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 16
- 229910052697 platinum Inorganic materials 0.000 claims description 15
- 238000000746 purification Methods 0.000 claims description 14
- GPNDARIEYHPYAY-UHFFFAOYSA-N palladium(ii) nitrate Chemical compound [Pd+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O GPNDARIEYHPYAY-UHFFFAOYSA-N 0.000 claims description 10
- 238000005299 abrasion Methods 0.000 claims description 9
- 230000005484 gravity Effects 0.000 claims description 8
- 239000002253 acid Substances 0.000 claims description 6
- AZDRQVAHHNSJOQ-UHFFFAOYSA-N alumane Chemical class [AlH3] AZDRQVAHHNSJOQ-UHFFFAOYSA-N 0.000 claims description 6
- 239000007864 aqueous solution Substances 0.000 claims description 2
- 238000010304 firing Methods 0.000 claims description 2
- 239000012266 salt solution Substances 0.000 claims description 2
- 239000007789 gas Substances 0.000 description 16
- 238000002360 preparation method Methods 0.000 description 15
- 238000000034 method Methods 0.000 description 11
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 10
- 229910052782 aluminium Inorganic materials 0.000 description 9
- 238000001354 calcination Methods 0.000 description 9
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 9
- 230000000694 effects Effects 0.000 description 7
- BNGXYYYYKUGPPF-UHFFFAOYSA-M (3-methylphenyl)methyl-triphenylphosphanium;chloride Chemical compound [Cl-].CC1=CC=CC(C[P+](C=2C=CC=CC=2)(C=2C=CC=CC=2)C=2C=CC=CC=2)=C1 BNGXYYYYKUGPPF-UHFFFAOYSA-M 0.000 description 6
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 6
- 239000013078 crystal Substances 0.000 description 6
- 238000007654 immersion Methods 0.000 description 6
- 239000000969 carrier Substances 0.000 description 5
- 230000007423 decrease Effects 0.000 description 5
- 229910052751 metal Inorganic materials 0.000 description 5
- 239000002184 metal Substances 0.000 description 5
- 238000012360 testing method Methods 0.000 description 5
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 4
- 238000009826 distribution Methods 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 4
- 229930195733 hydrocarbon Natural products 0.000 description 4
- 150000002430 hydrocarbons Chemical class 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- 239000004215 Carbon black (E152) Substances 0.000 description 3
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 3
- 239000000460 chlorine Substances 0.000 description 3
- 229910052801 chlorine Inorganic materials 0.000 description 3
- 230000006866 deterioration Effects 0.000 description 3
- 238000001035 drying Methods 0.000 description 3
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 3
- 229910052753 mercury Inorganic materials 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 231100000614 poison Toxicity 0.000 description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- TWRXJAOTZQYOKJ-UHFFFAOYSA-L Magnesium chloride Chemical compound [Mg+2].[Cl-].[Cl-] TWRXJAOTZQYOKJ-UHFFFAOYSA-L 0.000 description 2
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 2
- 235000011187 glycerol Nutrition 0.000 description 2
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 2
- 229910052737 gold Inorganic materials 0.000 description 2
- 239000010931 gold Substances 0.000 description 2
- 239000012194 insect media Substances 0.000 description 2
- 229910017604 nitric acid Inorganic materials 0.000 description 2
- PIBWKRNGBLPSSY-UHFFFAOYSA-L palladium(II) chloride Chemical compound Cl[Pd]Cl PIBWKRNGBLPSSY-UHFFFAOYSA-L 0.000 description 2
- 230000000704 physical effect Effects 0.000 description 2
- 230000007096 poisonous effect Effects 0.000 description 2
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 1
- 229910003609 H2PtCl4 Inorganic materials 0.000 description 1
- 229910002651 NO3 Inorganic materials 0.000 description 1
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- 239000000908 ammonium hydroxide Substances 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 239000012050 conventional carrier Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000007598 dipping method Methods 0.000 description 1
- 239000000017 hydrogel Substances 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 238000010348 incorporation Methods 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 239000002574 poison Substances 0.000 description 1
- 231100000572 poisoning Toxicity 0.000 description 1
- 230000000607 poisoning effect Effects 0.000 description 1
- 239000012495 reaction gas Substances 0.000 description 1
- 230000004043 responsiveness Effects 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 230000001988 toxicity Effects 0.000 description 1
- 231100000419 toxicity Toxicity 0.000 description 1
- 230000004580 weight loss Effects 0.000 description 1
Landscapes
- Exhaust Gas Treatment By Means Of Catalyst (AREA)
- Catalysts (AREA)
Description
【発明の詳細な説明】
本発明はアルミナ担体に白金及び／又はパラジウムを担
持させたガス浄化用酸化触媒とその製造法に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an oxidation catalyst for gas purification in which platinum and/or palladium is supported on an alumina carrier, and a method for producing the same.
白金及び／又はパラジウムをアルミナ担体に担持させた
ガス浄化用酸化触媒自体は公知であって従来から使用さ
れている。Oxidation catalysts for gas purification in which platinum and/or palladium are supported on an alumina carrier are known and have been used conventionally.
しかしながら、ガス浄化用酸化触媒は、その担体たるア
ルミナの物性が不充分であるため、特にこれを内燃機関
の排ガス浄化用触媒として使用した場合には、耐被毒性
に劣るばかりでなく、耐熱性も不充分であるため、微細
孔構造の崩壊による浄化性能及び機械的強度の低下が起
りやすい欠点があった。However, the oxidation catalyst for gas purification has insufficient physical properties of alumina, which is its carrier, so when it is used as a catalyst for purifying the exhaust gas of an internal combustion engine, it not only has poor toxicity resistance but also poor heat resistance. However, the cleaning performance and mechanical strength tend to deteriorate due to the collapse of the micropore structure.
本発明者らはこうした欠点を解消すべ（、粒状アルミナ
担体の性状と、その担体に白金及び／又はパラジウムを
担持させた触媒の性能との関係について精査した結果、
後述する如き特定な見掛嵩比重、細孔構造及び摩耗強度
を持つ粒状アルミナを担体として使用すれば、上記の如
き欠点のない触媒が得られることを見い出した。The present inventors sought to eliminate these drawbacks (as a result of careful investigation into the relationship between the properties of granular alumina carriers and the performance of catalysts in which platinum and/or palladium is supported on the carriers,
It has been found that if granular alumina having specific bulk specific gravity, pore structure and abrasion strength as described below is used as a carrier, a catalyst free from the above-mentioned drawbacks can be obtained.
さらにまた本発明者らは粒状アルミナを担体として白金
触媒を製造する場合には、触媒の焼成を水蒸気雰囲気で
行なうことにより、同じくパラジウム触媒を製造する場
合には、僅少量のアルミニウムをパラジウムと共存させ
ることにより、それぞれの触媒性能を向上させ得るとの
知見を得た。Furthermore, when the present inventors produce a platinum catalyst using granular alumina as a carrier, the catalyst is calcined in a steam atmosphere, and when a palladium catalyst is similarly produced, a small amount of aluminum coexists with palladium. It was found that the performance of each catalyst could be improved by doing so.
而して本発明に係るガス浄化用酸化触媒は、見掛嵩比重
が約０．２８〜０．４０Ｐ／ｃｃ、細孔容積が約１．２
０〜１．７ Ｑ ｃｃ、／ ｆ、平均細孔径が約２３０
〜３７０人であって、約１００λ以下の細孔を実質的に
含まず、摩耗減量が約３％以下である粒状アルミナ担体
と、この担体に担持された白金及び／又はパラジウムと
からなる。The oxidation catalyst for gas purification according to the present invention has an apparent bulk specific gravity of about 0.28 to 0.40 P/cc and a pore volume of about 1.2.
0~1.7 Q cc,/f, average pore size is about 230
It consists of a granular alumina carrier having a particle diameter of 370 mm, substantially free of pores of about 100λ or less, and having an abrasion loss of about 3% or less, and platinum and/or palladium supported on this carrier.
本発明に於て、触媒担体として使用される粒状アルミナ
は、従来のアルミナ担体に比較して見掛嵩密度が低く、
細孔容積及び平均細孔径が共に大きく、しかも約１００
Å以下の細孔を実質的に含まず、摩耗減量が少ないとい
う特長を有するが、そうした粒状アルミナは例えば次の
ような方法で製造することができる。In the present invention, the granular alumina used as a catalyst carrier has a lower apparent bulk density than conventional alumina carriers,
Both the pore volume and average pore diameter are large, and about 100
Such granular alumina can be produced, for example, by the following method.
すなわち、米国特許第２６２０３１４号に教示されてい
るが如き油滴法で得られるアルミナヒドロゲル粒子を、
アンモニア濃度が連続的に増大する水酸化アンモニウム
溶液中で熟成させ、しかる後、これを３０モル％以上の
水蒸気を含有する雰囲気中で焼成することにより、上記
の如き特性を有する粒状アルミナを得ることができる。That is, alumina hydrogel particles obtained by the oil drop method as taught in U.S. Pat. No. 2,620,314,
Granular alumina having the above characteristics is obtained by aging in an ammonium hydroxide solution in which the ammonia concentration continuously increases, and then calcining this in an atmosphere containing 30 mol% or more of water vapor. Can be done.
本発明のアルミナ担体に対する白金及び／又はパラジウ
ムの担持は、例えば塩化白金酸溶液及び／又は塩化パラ
ジウム溶液にアルミナ担体を浸漬するという常法によっ
てこれを行なうことができる。Platinum and/or palladium can be supported on the alumina support of the present invention by a conventional method, for example, by immersing the alumina support in a chloroplatinic acid solution and/or a palladium chloride solution.
そしてこうして得られる白金及び／又はパラジウム−ア
ルミナ触媒は、担体が低嵩比重であるが故に熱容量が小
さく、従って触媒の温度追随性に優れ、また担体の細孔
容積と平均細孔径が共に大きいため被毒物質を受容する
能力が高く、従って耐被毒性にも優れている。The platinum and/or palladium-alumina catalyst obtained in this way has a low heat capacity because the carrier has a low bulk specific gravity, and therefore has excellent temperature followability, and also because the pore volume and average pore diameter of the carrier are large. It has a high ability to accept poisonous substances and therefore has excellent poison resistance.
しかのみならず、本発明の触媒は約１ｏｏÅ以下の細孔
を殆ど含んでいないため、触媒の熱安定性が優れ、また
摩耗減量が少ないため、触媒床の振動によって起るとこ
ろの触媒の摩損が非常に少ない。In addition, since the catalyst of the present invention contains almost no pores of about 100 Å or less, it has excellent thermal stability and less loss of wear due to abrasion of the catalyst caused by vibration of the catalyst bed. There are very few.
ところで、アルミナ担体に白金又はパラジウムを担持さ
せる場合には、既述した通り塩化白金酸溶液又は塩化パ
ラジウム溶液を浸漬溶液として用いるのが通常であるが
、この場合には塩素の触媒への混入を免れず、これに原
因して触媒の性能が低下する。By the way, when platinum or palladium is supported on an alumina carrier, it is usual to use a chloroplatinic acid solution or a chloropalladium solution as an immersion solution as mentioned above, but in this case, it is necessary to avoid mixing chlorine into the catalyst. This inevitably causes a decrease in the performance of the catalyst.
またパラジウム−アルミナ触媒は白金−アルミナ触媒に
比較して、優れた活性を示す場合があり、また経済的な
面でも白金に比べ安価である利点を有するが、その反面
、酸素濃度が低い還元雰囲気中で高温にさらされるとパ
ラジウム金属の結晶が成長して触媒活性が損われる欠点
がある。Additionally, palladium-alumina catalysts may exhibit superior activity compared to platinum-alumina catalysts, and have the economical advantage of being cheaper than platinum. The drawback is that when exposed to high temperatures inside, palladium metal crystals grow and the catalytic activity is impaired.
従って、触媒への塩素の混入を抑制し、パラジウム触媒
にあってはパラジウムの結晶成長を阻止すれば、上記し
た特殊なアルミナ担体を使用することと相俟って触媒性
能をより一層改善することができる。Therefore, by suppressing the incorporation of chlorine into the catalyst and, in the case of palladium catalysts, by preventing the growth of palladium crystals, the catalyst performance can be further improved in combination with the use of the above-mentioned special alumina carrier. Can be done.
而して本発明に係る白金−アルミナ触媒の製造法は、既
述した如き細孔特性を有する粒状アルミナ担体を、塩化
白金酸溶液に浸漬して乾燥し、しかる後これを１５〜６
０モル％の水蒸気を含有する空気流中で約４２０〜６０
０℃、好ましくは約４５０〜５３０℃の温度条件下に３
０分間以上焼成することからなる。According to the method for producing a platinum-alumina catalyst according to the present invention, a granular alumina support having the above-mentioned pore characteristics is immersed in a chloroplatinic acid solution and dried, and then immersed in
420-60 in an air stream containing 0 mol% water vapor
3 at a temperature of 0°C, preferably about 450-530°C.
It consists of baking for 0 minutes or more.
この方法によれば、浸漬溶液に塩化白金酸を使用してい
るにも拘らず、触媒の塩素含有量を０．００〜０．０３
％に低下させることができる。According to this method, although chloroplatinic acid is used in the dipping solution, the chlorine content of the catalyst can be reduced from 0.00 to 0.03.
%.
上記の焼成に際してグリセリンなどの有機物を共存させ
ることは、白金の還元を促進するうえで好ましい。It is preferable to coexist an organic substance such as glycerin during the above-mentioned calcination in order to promote the reduction of platinum.
一方、本発明に係るパラジウム−アルミナ触媒の製造法
は、既述した如き細孔特性を有する粒状アルミナ担体な
、硝酸パラジウム溶液に浸漬して乾燥焼成後、アルミニ
ウ″ム塩水溶液に再度浸漬するか、あるいは硝酸パラジ
ウムとアルミニウム塩とを含有する水溶液に前記の粒状
アルミナ担体を浸漬し、次いで乾燥後焼成することから
なる。On the other hand, the method for producing a palladium-alumina catalyst according to the present invention involves immersing a granular alumina carrier having the above-mentioned pore characteristics in a palladium nitrate solution, drying and calcining it, and then immersing it again in an aqueous aluminum salt solution. Alternatively, the granular alumina carrier is immersed in an aqueous solution containing palladium nitrate and an aluminum salt, then dried and then fired.
つまり、この方法は塩化パラジウムを一旦還元して還元
パラジウムとなし、これを４モル倍の硝酸に溶解して得
られる硝酸パラジウム溶液を浸漬溶液として使用すると
共に、アルミニウム塩をアルミナ担体に含浸させてパラ
ジウムとアルミニウムを共存させることにより、パラジ
ウムの結晶成長を抑え、以ってパラジウム触媒の性能低
下を防止せんとするものである。In other words, in this method, palladium chloride is once reduced to become reduced palladium, and a palladium nitrate solution obtained by dissolving this in 4 times the mole of nitric acid is used as an immersion solution, and an aluminum salt is impregnated into an alumina carrier. By coexisting palladium and aluminum, the crystal growth of palladium is suppressed, thereby preventing a decline in the performance of the palladium catalyst.
本発明者らの知見によれば、パラジウム金属の結晶成長
の原因と考えられているパラジウム金属結晶粒子中の正
孔が、アルミニウム金属を共存させたことによって減少
せしめられ、このために還元雰囲気で高温にさらされて
もパラジウム金属の結晶成長が抑制され、従ってパラジ
ウム触媒の性能低下が防止できるものと推定される。According to the findings of the present inventors, the holes in palladium metal crystal particles, which are thought to be the cause of crystal growth of palladium metal, are reduced by the coexistence of aluminum metal, and for this reason, in a reducing atmosphere. It is presumed that the crystal growth of palladium metal is suppressed even when exposed to high temperatures, thereby preventing a decline in the performance of the palladium catalyst.
パラジウム触媒に含有せしめるアルミニウム量は、金属
として約０．１〜約５．０ｗｔ％の範囲を可とし、アル
ミニウム塩としては硝酸アルミニウムが好ましい。The amount of aluminum contained in the palladium catalyst can range from about 0.1 to about 5.0 wt% as a metal, and aluminum nitrate is preferred as the aluminum salt.
また硝酸パラジウム溶液には安定剤としてクエン酸を加
え、硝酸パラジウムの加水分解によるものと思われる浮
遊物の生成を避けることが望ましい。It is also desirable to add citric acid as a stabilizer to the palladium nitrate solution to avoid the formation of floating substances that may be caused by hydrolysis of palladium nitrate.
以上詳述して来たところから明らかな通り、本発明は触
媒担体として低見掛嵩比重で細孔容積及び平均細孔径が
共に大きく、しかも約１００Å以下の細孔を実質的に含
まず、そのうえ摩耗減量の少ない粒子アルミナを使用し
ているため、仮置通常の担持法で当該担体に白金又はパ
ラジウムを担持させても、得られる触媒は温度追随性、
耐被毒性、熱安定性及び耐摩耗性に優れた点で、通常の
アルミナ担体を使用した従来触媒を凌ぐ性能を発揮する
。As is clear from the above detailed description, the present invention provides a catalyst carrier that has a low apparent bulk specific gravity, a large pore volume and a large average pore diameter, and substantially does not contain pores of about 100 Å or less. In addition, since particulate alumina is used, which has a low abrasion loss, even if platinum or palladium is supported on the support using a temporary support method, the resulting catalyst will not follow temperature easily.
It exhibits superior performance to conventional catalysts using ordinary alumina carriers in terms of excellent poisoning resistance, thermal stability, and abrasion resistance.
さらにまた既述した通りの特定な細孔特性を有する粒状
アルミナを担体として白金触媒又はパラジウム触媒を製
造するに当り、白金触媒にあっては水蒸気の共存右下で
焼成を行なうことにより、パラジウム触媒にあっては少
量の金属アルミニウムを含有せしめることにより、それ
ぞれの触媒の性能を一段と向上させることができる。Furthermore, when producing platinum catalysts or palladium catalysts using granular alumina having specific pore characteristics as described above, the platinum catalysts are calcined in the lower right of the coexistence of water vapor. By containing a small amount of metallic aluminum, the performance of each catalyst can be further improved.
進んで実施例を示して本発明の効果をさらに具体的に説
明する。Next, the effects of the present invention will be explained in more detail with reference to Examples.
実施例 １
表１に示す如き性状の４種のアルミナ担体を使用して白
金担持触媒Ａ−Ｇ及びＮ−Ｐを得た。Example 1 Platinum-supported catalysts A-G and NP were obtained using four types of alumina supports having the properties shown in Table 1.
ここで使用した担体Ｙ及びＺは油滴法によらずに製造さ
れたものと推定されるところの現在市販されている典型
的なアルミナ担体であり、担体Ｘは油※※滴法によって
製造された通常のアルミナ担体である。Supports Y and Z used here are typical alumina supports currently on the market, which are presumed to have been manufactured without using the oil drop method, and support X was manufactured using the oil drop method. This is a normal alumina carrier.
表１から明らかな通り水銀圧入法による細孔容積が、担
体Ｘ−Ｚでは水銀圧入圧の昇圧、すなわち１５０００
ｐｓｉから３００００ ｐｓｉへの昇圧に伴って増大す
るのに対し、担体Ｗでは殆ど変化しない。As is clear from Table 1, the pore volume measured by the mercury intrusion method was increased by the mercury intrusion pressure in support X-Z, that is, 15,000
While it increases as the pressure increases from psi to 30,000 psi, carrier W hardly changes.
水銀圧入法では圧入圧１５０００ ｐｓｉで直径１１７
Å以上の細孔の容積が測定でき、圧入圧３００００ ｐ
ｓｉでは直径５９Å以上の細孔の容積が測定できるので
、１５０００ ｐｓｉから３００００ ｐｓｉへの昇圧
でも細孔容積が殆ど変化しないことは、直径５９〜１１
７人の細孔が殆ど存在しないことを意味する。In the mercury intrusion method, the diameter is 117 at an intrusion pressure of 15,000 psi.
The volume of pores larger than Å can be measured, and the injection pressure is 30,000 p.
Si can measure the volume of pores with a diameter of 59 Å or more, so the fact that the pore volume hardly changes even when the pressure is increased from 15,000 psi to 30,000 psi means that the pore volume of pores with a diameter of 59 to 11
7 means that there are almost no pores.
ちなみに、本発明の担体Ｗでは直径５９〜１１７人の細
孔の容積は僅か０．０１ ｃｃ／？にすぎず、従って担
体Ｗは約１００Å以下の細孔を実質的に含有していない
ものとみなすことができる。By the way, in the carrier W of the present invention, the volume of pores with a diameter of 59 to 117 is only 0.01 cc/? Therefore, it can be considered that the carrier W does not substantially contain pores of about 100 Å or less.
これに対して比較対象の担体Ｘ−２では、１５０００ｐ
ｓｉでの細孔容積と３００００ ｐｓｉでの細孔容積と
の差が最も小さい担体Ｘでも、直径５９〜１１７人の細
孔の容積は０．１２ｃｃ、Ｑ’であって、これは担体Ｗ
のそれの１０倍強に相当する。On the other hand, in the comparative carrier X-2, 15,000 p
Even for carrier
This corresponds to more than 10 times that of .
さらに担体Ｗは担体Ｙ及びＺと比較して低見掛嵩比重で
あり、また細孔容積及び平均細孔径がはるかに大きいこ
とがわかる。Furthermore, it can be seen that carrier W has a lower apparent bulk specific gravity than carriers Y and Z, and also has a much larger pore volume and average pore diameter.
さらに担体Ｗは担体Ｘと比較してみた場合、摩耗減量が
非常に少ないことからして耐摩耗性に優れていることが
明らかである。Furthermore, when comparing Carrier W with Carrier X, it is clear that the weight loss due to abrasion is very small, and the carrier W is superior in abrasion resistance.
触媒Ａの調製
濃縮を繰返して遊離酸を除いたＨ２ＰｔＣｌ４ を使用
し、担体１０００ｃｃ当り０．９１の白金を担持させる
量のＨ２ＰｔＣ１ａと、１０グのグリセリンを水で８０
０ｃｃに稀釈して浸漬溶液とした。Preparation of Catalyst A Using H2PtCl4 which had been repeatedly concentrated to remove the free acid, H2PtC1a in an amount to support 0.91 platinum per 1000 cc of support and 10 g of glycerin were mixed with 80 g of water.
It was diluted to 0 cc to prepare an immersion solution.
この溶液に担体Ｗ １０００ｃｃを加えてロータリーエ
バポレーター中で充分混合含浸させた後、湯浴上で乾燥
するまで蒸発させ、次いで１２０℃で３時間、さらに３
５０℃で３０分間乾燥した後、４０モル％の水蒸気を含
有する空気流中で５Ｖ＝１２５０の条件下に４８０℃で
２時間焼成して触媒Ａを得た。1000 cc of carrier W was added to this solution, thoroughly mixed and impregnated in a rotary evaporator, evaporated to dryness on a hot water bath, then heated at 120°C for 3 hours, and further 3 hours.
After drying at 50° C. for 30 minutes, catalyst A was obtained by calcining at 480° C. for 2 hours under the condition of 5V=1250 in an air stream containing 40 mol% water vapor.
触媒Ｂの調製
上記の触媒Ａを９８０℃のマツフル炉中で２４時間加熱
処理して触媒Ｂを得た。Preparation of Catalyst B Catalyst B was obtained by heating the above catalyst A in a Matsufuru furnace at 980°C for 24 hours.
触媒Ｃの調製
４８０°Ｃでの焼成を２０モル％の水蒸気を含む空気流
中で行なった以外は触媒Ａと同一方法で触媒Ｃを得た。Preparation of Catalyst C Catalyst C was obtained in the same manner as Catalyst A, except that the calcination at 480°C was carried out in an air stream containing 20 mol% water vapor.
触媒りの調製
焼成温度を４８０℃から４５０℃に低下させた以外は触
媒Ａと同一方法で触媒りを得た。Preparation of Catalyst A catalyst was obtained in the same manner as Catalyst A except that the firing temperature was lowered from 480°C to 450°C.
触媒Ｅの調製
焼成温度及び焼成時間をそれぞれ５００℃、１体※時間
とし、且つ水蒸気を含まない空気流中で焼成を行なった
以外は触媒Ａと同一方法で触媒Ｅを得た。Preparation of Catalyst E Catalyst E was obtained in the same manner as Catalyst A, except that the calcination temperature and calcination time were 500° C., 1 time per body, and the calcination was performed in an air stream containing no water vapor.
触媒Ｆの調製
担体Ｗに代えて担体Ｘを使用した以外は触媒Ａと同一方
法で触媒Ｆを得た。Preparation of Catalyst F Catalyst F was obtained in the same manner as Catalyst A except that Support X was used instead of Support W.
触媒Ｇの調製
上記の触媒Ｆを９８０℃のマツフル炉中で２４時間加熱
処理して触媒Ｇを得た。Preparation of Catalyst G Catalyst G was obtained by heating the above catalyst F in a Matsufuru furnace at 980°C for 24 hours.
触媒Ｎの調製
担体Ｗに代えて担体Ｙを使用した以外は触媒Ａと同一方
法で触媒Ｎを得た。Preparation of Catalyst N Catalyst N was obtained in the same manner as Catalyst A except that Support Y was used instead of Support W.
触媒Ｏの調製
上記の触媒Ｎを９８０℃のマツフル炉中で２４時間加熱
処理して触媒Ｏを得た。Preparation of Catalyst O Catalyst O was obtained by heat treating the above catalyst N in a Matsufuru furnace at 980°C for 24 hours.
触媒Ｐの調製
担体Ｗに代えて担体Ｚを使用した以外は触媒Ａと同一方
法で触媒Ｐを得た。Preparation of catalyst P Catalyst P was obtained in the same manner as catalyst A except that carrier Z was used instead of carrier W.
次に触媒Ａ、Ｃ−Ｅ、Ｎ及びＰの６種をそれぞれ使用し
て、ＣＨ４、Ｃ２Ｈ４、Ｃ３Ｈ５、ＣＯ，Ｈ２０，０□
及びＮ２を含む混合ガスを５Ｖ＝５００００１１ｒ
１の条件下に処理し、触媒床温度と炭化水素浄化率との
関係を測定した。Next, using six types of catalysts A, C-E, N and P, CH4, C2H4, C3H5, CO, H20,0□
and a mixed gas containing N2 at 5V=5000011r
1, and the relationship between catalyst bed temperature and hydrocarbon purification rate was measured.
結果を表２に示す。次に触媒Ａ、Ｎ及びＰそれぞれを、
自動車排ガス浄化性能テスト法（道路運送車両の保存基
準（運輸省令第３１条）による）に於けるエンジンのコ
ールドスタート時の浄化性能を重視した１１モードテス
トに供し、触媒床入口ガス温度と触媒床温度の上昇速度
との関係を求めた。The results are shown in Table 2. Next, each of catalysts A, N and P,
The 11-mode test focused on the purification performance at the time of cold start of the engine in accordance with the Automotive Exhaust Gas Purification Performance Test Method (according to the storage standards for road transport vehicles (Article 31 of the Ministry of Transport Ordinance)), and the catalyst bed inlet gas temperature and catalyst bed The relationship with the rate of temperature rise was determined.
結果を第１図に示す。The results are shown in Figure 1.
図中、実線は触媒床入口ガス温度を示し、２点鎖線は触
媒Ａの、１点鎖線は触媒Ｎの、また破線は触媒Ｐのそれ
ぞれ触媒床温度を示す。In the figure, the solid line indicates the catalyst bed inlet gas temperature, the two-dot chain line indicates the catalyst bed temperature of the catalyst A, the one-dot chain line indicates the catalyst N, and the broken line indicates the catalyst bed temperature of the catalyst P.
第１図から明らかな通り、触媒Ａはその担体の見掛嵩密
度が小さく、従って熱容量も小さいため、触媒Ｎ及びＰ
に比較して排出ガスの温度変化に対して優れた即応性を
示す。As is clear from FIG. 1, catalyst A has a small apparent bulk density of its carrier and therefore a small heat capacity, so catalysts N and P
It exhibits superior responsiveness to temperature changes in exhaust gas compared to other systems.
この結果は浄化効率にも確実に反映し、１１モードテス
ト法による排出ガス中の炭化水素重量は触媒Ａで０．２
２ｆ／１１モードテスト、触媒Ｎで０．３９ｆ／１１モ
ードテスト、触媒Ｐで０．３２ ｆ／１１モードテスト
であった。This result is definitely reflected in the purification efficiency, and the weight of hydrocarbons in exhaust gas by the 11-mode test method was 0.2 for catalyst A.
2f/11 mode test, 0.39f/11 mode test with catalyst N, and 0.32 f/11 mode test with catalyst P.
こうした触媒の温度追随性は自動車排ガス浄化触媒のみ
ならず、工業用排ガス浄化触媒についても大きな利点と
なる。The temperature followability of such a catalyst is a great advantage not only for automobile exhaust gas purification catalysts but also for industrial exhaust gas purification catalysts.
次に触媒Ａ及びＰをそれぞれ鉛で被毒させ、各触媒の活
性劣化度を測定した。Next, catalysts A and P were each poisoned with lead, and the degree of activity deterioration of each catalyst was measured.
反応ガスにはトルエンを濃度０．Ｑ５ｖｏ１％で使用し
、５Ｖ＝５０００００ｈｒ−’の条件下を採用した。The reaction gas contains toluene at a concentration of 0. It was used at Q5vo1%, and the conditions of 5V=500000hr-' were adopted.
活性劣化度はトルエンの転化反応を一次反応と見做して
次式によって算出した。The degree of activity deterioration was calculated by the following formula, regarding the toluene conversion reaction as a first-order reaction.
結果を表３に示す。ここでに１ −新触媒の反応速度定
数
に２−鉛被前触媒の反応速度定数
表３から明らかな通り、本発明の触媒Ａは触媒Ｐに比較
して活性劣化度が低いが、これは触媒Ａの担体Ｗが大き
な細孔容積と平均細孔径を有しているため、被毒物質に
対する受容能力が太きいことによるものである。The results are shown in Table 3. Here, 1 - Reaction rate constant of new catalyst 2 - Reaction rate constant of lead-treated catalyst As is clear from Table 3, catalyst A of the present invention has a lower degree of activity deterioration than catalyst P; This is because the carrier W of the catalyst A has a large pore volume and an average pore diameter, and therefore has a large ability to absorb poisonous substances.
実施例 ２
実施例１で用いた担体Ｗを使用して触媒Ｉ −Ｍを次の
方法によって調製した。Example 2 Using the carrier W used in Example 1, catalyst I-M was prepared by the following method.
触媒■の調製
一度還元した還元パラジウムを４モル倍の硝酸に溶解し
た硝酸パラジウムを使用し、担体１０００ｃｃ当り１．
１のパラジウムを担持させる量の硝酸パラジウムとクエ
ン酸０．７２を水で８００ｃｃに稀釈して浸漬溶液とし
、これに１０００ｃｃの担体Ｗを加えてロータリーエバ
ポレーター中で充分混合金浸させた後、湯浴上で乾燥す
るまで蒸発させ、次いで１２０℃で３時間乾燥後、５０
０℃で１時間焼成した。Preparation of Catalyst (1) Palladium nitrate prepared by dissolving reduced palladium once reduced in 4 times the mole of nitric acid is used, and 1.
Palladium nitrate and citric acid 0.72 in an amount to support 1 palladium were diluted with water to 800 cc to make an immersion solution, 1000 cc of carrier W was added to this, and the mixed gold was fully immersed in a rotary evaporator, and then the solution was soaked in hot water. Evaporate to dryness on a bath and then after drying for 3 hours at 120°C,
It was baked at 0°C for 1 hour.
次に、ＡＩとして１．４１のアルミニウムを含む硝酸ア
ルミニウムを水１２００ｃｃに溶解して浸漬溶液とし、
これを上記のＰｄ担持焼成物を加えて２時間放置し、次
いで余分の硝酸アルミニウム溶液を除去した後、湯浴上
で蒸発乾固させ、しかる後１２０℃で３時間乾燥してか
ら５００℃で１時間焼成して触媒■を得た。Next, aluminum nitrate containing 1.41 aluminum as AI was dissolved in 1200 cc of water to make an immersion solution.
The above-mentioned Pd-supported calcined product was added and left to stand for 2 hours. Next, after removing the excess aluminum nitrate solution, it was evaporated to dryness on a hot water bath, then dried at 120°C for 3 hours, and then heated at 500°C. After calcination for 1 hour, catalyst (2) was obtained.
触媒Ｊの調製
担体１０００ｃｃ当り１．８１のパラジウムを担持させ
る量の硝酸パラジウムと０．７１のクエン酸と、さらに
ＡＩとして０．７１のアルニウムを含む塩基性硝酸アル
ミニウムとを水で８００ｃｃに稀釈して浸漬溶液とした
。Preparation of Catalyst J Palladium nitrate in an amount to support 1.81 palladium per 1000 cc of support, 0.71 citric acid, and basic aluminum nitrate containing 0.71 aluminum as AI were diluted with water to 800 cc. It was made into an immersion solution.
この溶液に１０００ｃｃの担体Ｗを加えてロータリーエ
バポレーター中で充分混合金浸させ、しかる後湯浴上で
乾燥するまで蒸発させ、次いで１２０℃で３時間乾燥し
た後、５００℃で１時間焼成して触媒Ｊを得た。1000 cc of carrier W was added to this solution, thoroughly immersed in the mixed gold in a rotary evaporator, then evaporated until dry on a hot water bath, then dried at 120°C for 3 hours, and then calcined at 500°C for 1 hour. Catalyst J was obtained.
触媒にの調製
Ａ１として３．５１のアルミニウムを含む硝酸アツベニ
ウムを用いた以外＋ｄ虫媒■と同一方法で触媒Ｋを得た
。Preparation of Catalyst Catalyst K was obtained in the same manner as in +d insect medium ① except that atubenium nitrate containing 3.51 aluminum was used as A1.
触媒りの調製
Ａ１として１０．５＠のアルミニウムを含む硝酸アルミ
ニウムを使用した以外は触媒■と同一方法で触媒りを得
た。Preparation of Catalyst A Catalyst was obtained in the same manner as Catalyst ① except that aluminum nitrate containing 10.5@ aluminum was used as A1.
触媒Ｍの調製
硝酸アルミニウム溶液による処理を省略した以外は触媒
■と同一方法て哨虫媒Ｍを得た。Preparation of Catalyst M Insect medium M was obtained in the same manner as Catalyst (1) except that the treatment with aluminum nitrate solution was omitted.
触媒Ｉ〜Ｍをそれぞれ使用してＣＨ４、Ｃ２Ｈ４、Ｃ３
Ｈ８、ＣＯ，Ｈ２Ｏ，０□及びＮ２を含有する混合ガス
を５Ｖ＝５００００ ｈｒ刊の条件で処理し、各触媒の
炭化水素浄化率を測定した。CH4, C2H4, C3 using catalysts I to M, respectively
A mixed gas containing H8, CO, H2O, 0□ and N2 was treated under the conditions of 5V=50000 hr, and the hydrocarbon purification rate of each catalyst was measured.
結果を表４に示す。The results are shown in Table 4.
表４のカッコ内のデータは、各触媒を予め前記の混合ガ
ス（酸素量は理論反応量の１．２倍）中で８５０℃の温
度条件下に４時間熱処理してから炭化水素浄化テストに
供した場合の実験値であるが、アルミニウムを添加しな
い触媒は熱処理によって活性が低下するのに対し、アル
ミニウムを添加した触媒は殆ど活性低下がないことが表
４の結果から理解できる。The data in parentheses in Table 4 shows that each catalyst was heat-treated in the above-mentioned mixed gas (oxygen amount is 1.2 times the theoretical reaction amount) at a temperature of 850°C for 4 hours before being subjected to a hydrocarbon purification test. It can be seen from the results in Table 4 that the activity of the catalyst without aluminum decreases due to heat treatment, whereas the activity of the catalyst with aluminum hardly decreases, which is the experimental value when the catalyst was used.
次に実施例１及び２で使用した触媒の物性をまとめて表
５に示す。Next, the physical properties of the catalysts used in Examples 1 and 2 are summarized in Table 5.
また触媒Ｂ、Ｇ、０はそれぞれ触媒Ａ、Ｆ。Catalysts B, G, and 0 are catalysts A and F, respectively.
Ｎを９８０℃で２４時間熱処理した触媒であるが、これ
ら６種と触媒Ｐの細孔分布を第２図に示す。The pore distribution of these six types and catalyst P is shown in Figure 2, which is a catalyst obtained by heat-treating N at 980°C for 24 hours.
表５及び第２図に示す結果から首肯される通り、担体Ｗ
を使用した触媒Ａと、熱処理された触媒Ｂとの間には細
孔分布に殆ど変化が認められないのに対し、従来の担体
を使用した触媒は、熱処理によって細孔分布が大幅に変
化する。As confirmed from the results shown in Table 5 and FIG.
There is almost no change in the pore distribution between Catalyst A, which used a carrier, and Catalyst B, which was heat-treated, whereas the pore distribution of the catalyst, which uses a conventional carrier, changes significantly upon heat treatment. .
この実験事実は本発明のアルミナ担体を使用した触媒が
熱安定性に優れていることを物語るものに外ならない。This experimental fact proves that the catalyst using the alumina carrier of the present invention has excellent thermal stability.
第１図は触媒床入口ガス温度と触媒床温度との関係を示
すグラフであり、第２図は触媒の細孔分布を示すグラフ
である。FIG. 1 is a graph showing the relationship between the catalyst bed inlet gas temperature and the catalyst bed temperature, and FIG. 2 is a graph showing the pore distribution of the catalyst.
Claims (1)
孔容積が約１．２０〜１．７ｏｃｃ／Ｐ、平均細孔径が
約２３０〜３７０人であって、約１００Å以下の細孔を
実質的に含まず、摩耗減量が約３％以下である粒状アル
ミナ担体と、この担体に担持された白金及び／又はパラ
ジウムとからなるガス浄化用酸化触媒。 ２ 見掛嵩比重が約０．２８〜０．４０？／ｃｃ、細孔
容積が約１．２０〜１．７０ｃｃ／７、平均細孔径が約
２３０〜３７０人であって、約１００Å以下の細孔を実
質的に含まず、摩耗減量が約３％以下である粒状アルミ
ナ担体を、塩化白金酸溶液に浸漬して乾燥し、次いで１
５〜６０モル％の水蒸気を含有する空気流中で約４２０
〜６００℃の温度条件下に３０分間以上暁焼成ることか
らなるガス浄化用白金−アルミナ酸化触媒の製造法。 ３ 見掛嵩比重が約０．２８〜０．４０Ｐ／ｃｃ、細孔
容積が約１，２０〜１．７０ｃｃ／ｌｉ？、平均細孔径
が約２３０〜３７０人であって、約１００Å以下の細孔
を実質的に含まず、摩耗減量が約３％以下である粒状ア
ルミナ担体を、硝酸パラジウム溶液に浸漬して乾燥焼成
後、アルミニウム塩水溶液に再度浸漬するか、あるいは
硝酸パラジウムとアルミニウム塩とを含有する水溶液に
前記の粒状アルミナ担体を浸漬し、次いで乾燥後焼成す
ることからなるガス浄化用アルミニウム含有パラジウム
−アルミナ酸化触媒の製造法。[Claims] 1. The apparent bulk specific gravity is about 0.28 to 0.40 g/cc, the pore volume is about 1.20 to 1.7 occ/P, and the average pore diameter is about 230 to 370 g/cc. An oxidation catalyst for gas purification, comprising a granular alumina support that does not substantially contain pores of about 100 Å or less and has an abrasion loss of about 3% or less, and platinum and/or palladium supported on this support. 2 Apparent bulk specific gravity is approximately 0.28 to 0.40? /cc, pore volume is approximately 1.20 to 1.70 cc/7, average pore diameter is approximately 230 to 370, substantially does not contain pores of approximately 100 Å or less, and wear loss is approximately 3%. The following granular alumina support was immersed in a chloroplatinic acid solution and dried, then 1
420 in an air stream containing 5 to 60 mol% water vapor.
A method for producing a platinum-alumina oxidation catalyst for gas purification, which comprises firing at a temperature of ~600°C for 30 minutes or more. 3 Apparent bulk specific gravity is about 0.28-0.40P/cc, pore volume is about 1,20-1.70cc/li? A granular alumina carrier having an average pore diameter of about 230 to 370 pores, substantially free of pores of about 100 Å or less, and having an abrasion loss of about 3% or less is immersed in a palladium nitrate solution and dried and fired. After that, the granular alumina support is immersed again in an aqueous aluminum salt solution, or the granular alumina support is immersed in an aqueous solution containing palladium nitrate and an aluminum salt, and then dried and fired. manufacturing method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP53010558A JPS5926335B2 (en) | 1978-02-03 | 1978-02-03 | Platinum group oxidation catalyst and its manufacturing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP53010558A JPS5926335B2 (en) | 1978-02-03 | 1978-02-03 | Platinum group oxidation catalyst and its manufacturing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS54112392A JPS54112392A (en) | 1979-09-03 |
| JPS5926335B2 true JPS5926335B2 (en) | 1984-06-26 |
Family
ID=11753571
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP53010558A Expired JPS5926335B2 (en) | 1978-02-03 | 1978-02-03 | Platinum group oxidation catalyst and its manufacturing method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5926335B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2014141903A1 (en) * | 2013-03-15 | 2014-09-18 | エヌ・イーケムキャット株式会社 | Oxidation catalyst and exhaust gas purification device using same |
-
1978
- 1978-02-03 JP JP53010558A patent/JPS5926335B2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS54112392A (en) | 1979-09-03 |
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