JP4315857B2 - Platinum solution and method for producing catalyst using the same - Google Patents
Platinum solution and method for producing catalyst using the same Download PDFInfo
- Publication number
- JP4315857B2 JP4315857B2 JP2004129858A JP2004129858A JP4315857B2 JP 4315857 B2 JP4315857 B2 JP 4315857B2 JP 2004129858 A JP2004129858 A JP 2004129858A JP 2004129858 A JP2004129858 A JP 2004129858A JP 4315857 B2 JP4315857 B2 JP 4315857B2
- Authority
- JP
- Japan
- Prior art keywords
- platinum
- solution
- nitric acid
- catalyst
- present
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 title claims description 117
- 229910052697 platinum Inorganic materials 0.000 title claims description 58
- 239000003054 catalyst Substances 0.000 title claims description 25
- 238000004519 manufacturing process Methods 0.000 title claims description 10
- IXSUHTFXKKBBJP-UHFFFAOYSA-L azanide;platinum(2+);dinitrite Chemical compound [NH2-].[NH2-].[Pt+2].[O-]N=O.[O-]N=O IXSUHTFXKKBBJP-UHFFFAOYSA-L 0.000 claims description 25
- 229910017604 nitric acid Inorganic materials 0.000 claims description 25
- 238000002835 absorbance Methods 0.000 claims description 13
- 229910002651 NO3 Inorganic materials 0.000 claims description 11
- 239000003513 alkali Substances 0.000 claims description 9
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 8
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 claims description 4
- CETPSERCERDGAM-UHFFFAOYSA-N ceric oxide Chemical compound O=[Ce]=O CETPSERCERDGAM-UHFFFAOYSA-N 0.000 claims description 2
- 229910000422 cerium(IV) oxide Inorganic materials 0.000 claims description 2
- 239000002131 composite material Substances 0.000 claims 1
- 239000000243 solution Substances 0.000 description 57
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 18
- 230000000052 comparative effect Effects 0.000 description 11
- 238000000746 purification Methods 0.000 description 9
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 9
- 230000032683 aging Effects 0.000 description 8
- 239000002245 particle Substances 0.000 description 8
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- 239000013078 crystal Substances 0.000 description 6
- 238000006116 polymerization reaction Methods 0.000 description 6
- 229910000510 noble metal Inorganic materials 0.000 description 5
- 239000000843 powder Substances 0.000 description 5
- 238000002360 preparation method Methods 0.000 description 5
- 238000001479 atomic absorption spectroscopy Methods 0.000 description 4
- 238000011068 loading method Methods 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 238000003756 stirring Methods 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 3
- 239000008188 pellet Substances 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 3
- 238000005245 sintering Methods 0.000 description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000011156 evaluation Methods 0.000 description 2
- 238000007654 immersion Methods 0.000 description 2
- 150000002736 metal compounds Chemical class 0.000 description 2
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- 229910001361 White metal Inorganic materials 0.000 description 1
- 229910021536 Zeolite Inorganic materials 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 239000000460 chlorine Substances 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- 239000011362 coarse particle Substances 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 description 1
- 238000007598 dipping method Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000002330 electrospray ionisation mass spectrometry Methods 0.000 description 1
- 238000007429 general method Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000011259 mixed solution Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 125000000449 nitro group Chemical group [O-][N+](*)=O 0.000 description 1
- 150000003058 platinum compounds Chemical class 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 238000000235 small-angle X-ray scattering Methods 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 238000004448 titration Methods 0.000 description 1
- 239000010969 white metal Substances 0.000 description 1
- 239000010457 zeolite Substances 0.000 description 1
Landscapes
- Catalysts (AREA)
- Exhaust Gas After Treatment (AREA)
- Exhaust Gas Treatment By Means Of Catalyst (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
Description
本発明は、ジニトロジアンミン白金硝酸溶液、及び当該溶液を用いた白金触媒の製造方法に関する。 The present invention relates to a dinitrodiammine platinum nitrate solution and a method for producing a platinum catalyst using the solution.
内燃機関から排出される有害ガス成分、HC、CO、NOｘを効率よく浄化することを目的として、一般的に貴金属触媒が使用されている。その調製において、貴金属元素は重要な役割を担っており、用途に応じて各種貴金属化合物が選択されている。 In order to efficiently purify harmful gas components, HC, CO, and NOx discharged from an internal combustion engine, a noble metal catalyst is generally used. In the preparation, noble metal elements play an important role, and various noble metal compounds are selected depending on the application.
貴金属触媒の１つである白金触媒は、白金属化合物溶液中に触媒用担体を浸漬して還元担持することによって製造されうる。中でもジニトロジアンミン白金硝酸溶液は、塩素を含まず、化合物が分解されやすいという特性により一般的に利用されている。 A platinum catalyst, which is one of the noble metal catalysts, can be produced by dipping and supporting a catalyst carrier in a white metal compound solution. Among them, dinitrodiammine platinum nitrate solution is generally used because it does not contain chlorine and the compound is easily decomposed.
ジニトロジアンミン白金硝酸溶液は、一般的に、出発物質であるジニトロジアンミン白金結晶を硝酸水溶液に添加し、６０〜10０℃で溶解し、熟成を行うことによって調製される。尚、この調製段階における熟成とは白金錯体の重合を意味するものであり、ジニトロジアンミン白金[(NH3)2(NO2)2Pt]のニトロ基が硝酸の添加により増大することを表している。 The dinitrodiammine platinum nitric acid solution is generally prepared by adding dinitrodiammine platinum crystals as a starting material to an aqueous nitric acid solution, dissolving at 60 to 100 ° C., and aging. The aging in this preparation stage means polymerization of a platinum complex, and represents that the nitro group of dinitrodiammine platinum [(NH 3 ) 2 (NO 2 ) 2 Pt] is increased by the addition of nitric acid. Yes.
しかしながら、当該溶液の調製は、ジニトロジアンミン白金結晶が硝酸に溶解しにくく、且つ高温での調製により白金化合物の沈殿が生じるという欠点を有している。これらの欠点を改善することを目的とした白金溶液の製法も提案されているが（特許文献１及び２参照）、当該製法により調製されたジニトロジアンミン白金硝酸溶液はシンタリングしやすく、その結果担体に対する担持効率が低く、更には当該溶液によって得られる触媒が性能劣化しやすいという問題点を有していた。
従来、このような問題の原因となるシンタリングを解消するためには、白金が担体に対し高分散に担持し、且つ白金粒子の比表面積が広い触媒、すなわち白金粒子が小さい触媒を調製することが必要であると考えられており、そのような触媒を調製することに主眼が置かれていた。 Conventionally, in order to eliminate the sintering that causes such a problem, a catalyst in which platinum is supported in a highly dispersed manner on a support and the platinum particles have a large specific surface area, that is, a catalyst having small platinum particles is prepared. Has been considered necessary, and the focus has been on preparing such catalysts.
しかしながら、本発明者は、上記シンタリングの解消にはある程度の白金粒子の大きさが必要であると考え、白金触媒の製造において一般的に使用されているジニトロジアンミン白金硝酸溶液を調製する際の熟成条件を変えることによって、錯体の重合度を調節することを試みた。その結果、従来ジニトロジアンミン白金硝酸溶液を調製するのに必要とされていた白金：硝酸の重量比＝１：０．７〜１．６（特許文献１参照）を、白金：硝酸の重量比＝１：０．７未満にして調製された溶液が、担体に高効率で担持し、且つその結果得られた触媒の浄化特性が向上することが明らかとなった。更に、このように調製されたジニトロジアンミン白金硝酸溶液が、４２０ｎｍの吸光度において一定の値を示すことも明らかとなった。 However, the present inventor considers that a certain amount of platinum particle size is necessary to eliminate the sintering, and therefore, when preparing a dinitrodiammine platinum nitric acid solution generally used in the production of a platinum catalyst. An attempt was made to adjust the degree of polymerization of the complex by changing the aging conditions. As a result, the weight ratio of platinum: nitric acid, which was conventionally required for preparing dinitrodiammine platinum nitrate solution = 1: 0.7 to 1.6 (see Patent Document 1), the weight ratio of platinum: nitric acid = It was revealed that a solution prepared with a ratio of less than 1: 0.7 was supported on the support with high efficiency, and the purification characteristics of the resulting catalyst were improved. Furthermore, it was also clarified that the dinitrodiammine platinum nitrate solution thus prepared shows a constant value at an absorbance of 420 nm.
上記発見に基づき、本発明は、１Ｌ当たり白金１ｇとなるように純水で希釈した場合に、４２０ｎｍにおける吸光度が１．５〜３であることを特徴とするジニトロジアンミン白金硝酸溶液を提供する。更に、本発明は、当該白金溶液を担持させることにより耐久性が向上した白金担持触媒を提供する。 Based on the above discovery, the present invention provides a dinitrodiammine platinum nitrate solution characterized by having an absorbance at 420 nm of 1.5 to 3 when diluted with pure water to 1 g of platinum per liter. Furthermore, the present invention provides a platinum-supported catalyst having improved durability by supporting the platinum solution.
本発明のジニトロジアンミン白金硝酸溶液は、従来の製法によって調製した溶液よりも高効率で担体に担持する。このような効果は、ジニトロジアンミン白金硝酸溶液を調製する際の白金当たりの硝酸添加量を従来のものより減少させることで白金溶液の熟成条件が変化したためであると考えられる。具体的には、この熟成条件の変更の結果、白金錯体の重合度が高く、初期粒径が比較的大きくシンタリングしにくい白金溶液が高効率で担持した担体をもたらすものと思われる。事実、本発明の白金溶液は、上述のように硝酸の添加量を調節した結果、初期粒径が適当な大きさに調節されることがＥＳＩ−ＭＳ、ＳＡＸＳ、ＸＲＤ等の分析から確認されている。また、粒径の大きさが比較的均一であるため、粗大粒子を形成しにくいことも上記効果の原因と考えられる。 The dinitrodiammine platinum nitrate solution of the present invention is supported on a carrier with higher efficiency than a solution prepared by a conventional production method. Such an effect is considered to be because the aging conditions of the platinum solution were changed by reducing the amount of nitric acid added per platinum when preparing the dinitrodiammine platinum nitric acid solution from the conventional one. Specifically, as a result of the change in the aging conditions, it is considered that a platinum solution having a high degree of polymerization of the platinum complex and a relatively large initial particle diameter and difficult to sinter is provided with a highly efficient support. In fact, the platinum solution of the present invention has been confirmed from the analysis of ESI-MS, SAXS, XRD, etc. that the initial particle size is adjusted to an appropriate size as a result of adjusting the amount of nitric acid added as described above. Yes. Moreover, since the size of the particle size is relatively uniform, it is considered that the above effect is also caused by difficulty in forming coarse particles.
更に、本発明の白金溶液を担持させた触媒の浄化特性が向上したことの理由としては、あらかじめ初期粒径を比較的大きなものに調節した白金を担持することにより、シンタリングが抑制された結果であると考えられる。 Furthermore, the reason why the purification property of the catalyst carrying the platinum solution of the present invention has improved is that the sintering was suppressed by carrying platinum whose initial particle size was adjusted to be relatively large in advance. It is thought that.
第一の側面として、本発明は、１ｇ／Ｌの白金濃度となるように純水で希釈した場合に、４２０ｎｍにおける吸光度が１．５〜３であることを特徴とするジニトロジアンミン白金硝酸溶液を提供する。 As a first aspect, the present invention provides a dinitrodiammine platinum nitric acid solution characterized by having an absorbance at 420 nm of 1.5 to 3 when diluted with pure water to a platinum concentration of 1 g / L. provide.
本発明のジニトロジアンミン白金硝酸溶液を調製するためには、調製の際に以下の条件を用いて熟成条件を変化させる必要がある。 In order to prepare the dinitrodiammine platinum nitrate solution of the present invention, it is necessary to change the aging conditions using the following conditions during the preparation.
最初に、１）白金：純硝酸の重量比が１：０．７未満となり、且つ白金濃度が５０〜２００ｇ／Ｌとなるようにジニトロジアンミン白金結晶を硝酸と純水の混合溶液に添加して溶解する。 First, 1) dinitrodiammine platinum crystals were added to a mixed solution of nitric acid and pure water so that the weight ratio of platinum: pure nitric acid was less than 1: 0.7 and the platinum concentration was 50 to 200 g / L. Dissolve.
尚、前記重量比以上に硝酸を添加することは、熟成進行速度が非常に遅くなるため好ましくない。また、上記白金濃度以外の範囲では熟成の調整が困難である。 In addition, it is not preferable to add nitric acid to the weight ratio or more because the aging progress rate becomes very slow. Moreover, it is difficult to adjust the aging in a range other than the platinum concentration.
続いて、２）上記溶液を常圧下９０〜１０５℃、好ましくは９７〜１０２℃の温度で、５〜１００時間煮沸する。 Subsequently, 2) the solution is boiled for 5 to 100 hours at a temperature of 90 to 105 ° C., preferably 97 to 102 ° C. under normal pressure.
当該段階において、溶液中の白金の価数が２価から４価へと増大する反応が進行し、白金溶液の熟成が行われる。ここで、上記温度以外では当該反応の効率が低いため好ましくない。 In this stage, a reaction in which the valence of platinum in the solution increases from divalent to tetravalent proceeds, and the platinum solution is aged. Here, other than the above temperature, the efficiency of the reaction is low, which is not preferable.
上記１）及び２）の段階により調製される本発明の白金溶液は、第一の特性として、当該溶液を１ｇ／Ｌの白金濃度となるように純水で希釈した場合に、４２０nｍにおける吸光度が１．５〜３であることを特徴とする。ここで、４２０nｍの波長は、本発明において貴金属の重合度を判断する指標として使用され、この波長における吸光度が高い程重合度は高く、そして吸光度が低いほど重合度は低いと考えられる。本発明の溶液を担体に担持させたときの白金の初期粒径分布、担持効率、及び触媒の浄化効率の観点から、当該範囲が好ましい。 The platinum solution of the present invention prepared by the steps 1) and 2) has, as a first characteristic, an absorbance at 420 nm when the solution is diluted with pure water so as to have a platinum concentration of 1 g / L. It is 1.5-3. Here, the wavelength of 420 nm is used as an index for judging the degree of polymerization of the noble metal in the present invention. The higher the absorbance at this wavelength, the higher the degree of polymerization, and the lower the absorbance, the lower the degree of polymerization. This range is preferable from the viewpoints of the initial particle size distribution of platinum when the solution of the present invention is supported on a carrier, the supporting efficiency, and the purification efficiency of the catalyst.
本発明における吸光度は、上記濃度に調整した試料を石英セル中で分光光度計Ｕ−２０００Ａ（日立製作所）において４２０ｎｍの吸光度で測定することによって実施した。また、対照液には純水を使用した。ここで、本発明の白金溶液の吸光度は、上記分光光度計を用いて上記方法により測定したものであり、別の分光光度計を用いて上記のものと異なった条件で測定した場合に、吸光度が異なることは当業者にとって自明であろう。 The absorbance in the present invention was measured by measuring the sample adjusted to the above concentration in a quartz cell with a spectrophotometer U-2000A (Hitachi) at an absorbance of 420 nm. Further, pure water was used as a control solution. Here, the absorbance of the platinum solution of the present invention was measured by the above method using the above spectrophotometer, and when measured under different conditions from the above using another spectrophotometer, the absorbance Will be obvious to those skilled in the art.
続いて、第二の側面として、本発明は、アルカリ消費量が０．１５〜０．３５であることを特徴とするジニトロジアンミン白金硝酸溶液を提供する。 Subsequently, as a second aspect, the present invention provides a dinitrodiammine platinum nitric acid solution characterized in that the alkali consumption is 0.15 to 0.35.
本明細書において使用するアルカリ消費量とは、本発明の溶液の酸濃度を示す指標であり、本明細書においては、０．１Ｎの水酸化ナトリウムによる中和滴定反応に基づいて以下の式：
上記アルカリ消費量は、好ましくは０．１５〜０．３である。当該範囲内にある本発明のジニトロジアンミン白金硝酸溶液は、当該溶液中に高濃度で白金が含まれている場合にもそれらを高効率で担体に担持させることができる。 The alkali consumption is preferably 0.15 to 0.3. The dinitrodiammine platinum nitric acid solution of the present invention within the above range can be supported on the carrier with high efficiency even when the solution contains platinum at a high concentration.
更に、第三の側面において、本発明は、上記ジニトロジアンミン白金硝酸溶液中に担体を浸漬して白金を担体上に担持することを特徴とする白金触媒の製造方法を提供する。 Furthermore, in the third aspect, the present invention provides a method for producing a platinum catalyst, wherein the platinum is supported on the carrier by immersing the carrier in the dinitrodiammine platinum nitrate solution.
上記白金触媒は、白金溶液中に担体を浸漬担持することによって調製される。尚、本発明において使用される担体は、例えば、アルミナ、ジルコニア、セリア、及びその複合酸化物等であり、その他にもシリカ、チタニア、ゼオライトが挙げられる。尚、担体はハニカム等の基材上にコーティングしたものでもよい。 The platinum catalyst is prepared by immersing and supporting a carrier in a platinum solution. The carrier used in the present invention is, for example, alumina, zirconia, ceria, and complex oxides thereof, and other examples include silica, titania, and zeolite. The carrier may be a coating on a substrate such as a honeycomb.
本発明における浸漬担持方法は、触媒の製造において一般的な方法によって行うことが可能であり、具体的には上記担体を白金溶液中に浸し、白金成分を担体表面に吸着させ、乾燥、焼成、還元することによって行うことができる。 The immersion supporting method in the present invention can be carried out by a general method in the production of a catalyst. Specifically, the support is immersed in a platinum solution, the platinum component is adsorbed on the surface of the support, dried, calcined, This can be done by reducing.
上記浸漬担持方法の担持効率は、原子吸光分光法（AA）によって担持前の白金溶液中の白金濃度から担持後の白金溶液中の白金濃度を差し引くことによって算出される。 The supporting efficiency of the immersion supporting method is calculated by subtracting the platinum concentration in the platinum solution after supporting from the platinum concentration in the platinum solution before supporting by atomic absorption spectroscopy (AA).
尚、本発明の白金溶液は、排ガス浄化用の触媒に限定されず、白金を高効率で担持することが必要とされるあらゆる触媒に適用可能である。 The platinum solution of the present invention is not limited to a catalyst for exhaust gas purification, and can be applied to any catalyst that needs to carry platinum with high efficiency.
以下の実施例を用いて、本発明の発明を更に具体的に説明し、本発明の白金溶液の担体に対する担持効率及び当該溶液を担持させた触媒のモデルガスに対する浄化特性を実証する。尚、本発明はこれらの実施例に限定されるものではない。 The invention of the present invention will be described more specifically with reference to the following examples, and the supporting efficiency of the platinum solution of the present invention with respect to the carrier and the purification characteristics of the catalyst supporting the solution with respect to the model gas will be demonstrated. The present invention is not limited to these examples.
実施例１〜３及び比較例１，２
ジニトロジアンミン白金結晶１６７ｇに対し、白金：硝酸の重量比が１：０．７未満となり、且つ最終的に所定のアルカリ消費量となるように、硝酸を添加し、続いて全体で１Ｌとなるように純水を添加する。この溶液を攪拌しながら１００℃前後で所定時間過熱し、実施例１〜３を調製した。尚、上記方法において、白金：硝酸の重量比が１：０．７以上となるように硝酸を添加して同様に調製したものを比較例１，２とした。
Examples 1 to 3 and Comparative Examples 1 and 2
Nitric acid is added to 167 g of dinitrodiammine platinum crystal so that the weight ratio of platinum: nitric acid is less than 1: 0.7, and finally a predetermined alkali consumption is obtained, so that the total amount is 1 L. Add pure water. While stirring this solution, the mixture was heated at around 100 ° C. for a predetermined time to prepare Examples 1 to 3. In the above method, Comparative Examples 1 and 2 were prepared in the same manner by adding nitric acid so that the weight ratio of platinum: nitric acid was 1: 0.7 or more.
比較例３
ジニトロジアンミン白金結晶１６７ｇに対し、白金：硝酸の重量比が１：０．７以上となり、且つ最終的に所定のアルカリ消費量となるように、硝酸を添加し、続いて全体で１Ｌとなるように純水を添加する。この溶液を攪拌しながら約９５℃で２０時間過熱し、比較例３を調製した。
Comparative Example 3
Nitric acid is added so that the weight ratio of platinum: nitric acid is 1: 0.7 or more with respect to 167 g of dinitrodiammine platinum crystal, and finally the predetermined alkali consumption is reached. Add pure water. This solution was heated at about 95 ° C. for 20 hours with stirring to prepare Comparative Example 3.
比較例４
ジニトロジアンミン白金結晶８３．３ｇに対し、白金：硝酸の重量比が１：０．７以上となり、且つ最終的に所定のアルカリ消費量となるように、硝酸を添加し、続いて全体で１Ｌとなるように純水を添加する。この溶液を攪拌しながら約９５℃で１５時間過熱し、比較例３を調製した。
Comparative Example 4
To 83.3 g of dinitrodiammine platinum crystal, nitric acid was added so that the weight ratio of platinum: nitric acid was 1: 0.7 or more and finally a predetermined alkali consumption was obtained, and then the total amount was 1 L. Add pure water so that This solution was heated with stirring at about 95 ° C. for 15 hours to prepare Comparative Example 3.
以下の表１に上記実施例１〜３及び比較例１，２の溶液の吸光度、アルカリ消費量、加熱時間、及び各溶液の安定性を示す。表１に記載のように、実施例１〜３の溶液は、いずれも４２０ｎｍにおける吸光度が１．５〜３．０の範囲内にあるが、比較例１〜４の溶液はいずれも当該範囲外である。
続いて、上述のようにして得られた実施例及び比較例の白金溶液のアルミナ粉末に対する担持効率について検討した。担持効率は、アルミナ粉末添加前及び添加後の白金溶液濃度を原子吸光分析法（AA）で測定し、以下の計算式：
[（担持前の溶液中の白金濃度(a)）−（担持後の溶液中の白金濃度(b)）]÷ a ×１００
により算出した。上記担持は、アルミナ粉末を１又は４重量％となるように各白金溶液中に添加した後、１時間攪拌することで行った。結果を以下の表２に示す。尚、比較例２は前記調製段階において沈殿が生じたために実施していない。
[(Platinum concentration in solution before loading (a)) − (Platinum concentration in solution after loading (b))] ÷ a × 100
Calculated by The above loading was performed by adding alumina powder to each platinum solution to 1 or 4% by weight and then stirring for 1 hour. The results are shown in Table 2 below. Comparative Example 2 was not carried out because precipitation occurred in the preparation stage.
上述のように調製した１重量％の白金担持アルミナ粉末をペレットにし、これを用いてモデルガスに対する本発明の白金担持アルミナに対する浄化特性の評価を行った。浄化特性の評価は、９００℃の大気中で白金担持アルミナ粉末のペレットを５時間耐久させた後に、４００℃のストイキ時のモデルガス（NO：８００ppm、CO：５０００ppm、及びHC：１０００ppm）の浄化率を測定することによって行った。尚、浄化率は、上記モデルガスを入りガスとし、そして当該ガスが上記ペレットを詰めたガラスカラムを通過した際に排出されるものを出口ガスとし、それらのガス中に含まれる各成分の濃度の差異から算出した。評価結果を以下の表３に示す。
この結果、本発明の白金担持触媒は、NO、CO、又はHCのいずれのガスに対しても比較例のものと比較して高い浄化特性を示すことが明らかとなった。 As a result, it has been clarified that the platinum-supported catalyst of the present invention exhibits high purification characteristics with respect to any gas of NO, CO, or HC as compared with the comparative example.
Claims (4)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2004129858A JP4315857B2 (en) | 2004-04-26 | 2004-04-26 | Platinum solution and method for producing catalyst using the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2004129858A JP4315857B2 (en) | 2004-04-26 | 2004-04-26 | Platinum solution and method for producing catalyst using the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2005306700A JP2005306700A (en) | 2005-11-04 |
| JP4315857B2 true JP4315857B2 (en) | 2009-08-19 |
Family
ID=35435872
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2004129858A Expired - Lifetime JP4315857B2 (en) | 2004-04-26 | 2004-04-26 | Platinum solution and method for producing catalyst using the same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4315857B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10189011B2 (en) | 2016-09-15 | 2019-01-29 | Toyota Jidosha Kabushiki Kaisha | Exhaust gas purifying catalyst and method for producing the same |
| DE102023108096A1 (en) | 2022-04-28 | 2023-11-02 | Cataler Corporation | CATALYST FOR FUEL CELL |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5759695B2 (en) | 2010-09-24 | 2015-08-05 | 株式会社キャタラー | Method for producing supported catalyst for fuel cell |
| JP6141741B2 (en) | 2013-10-09 | 2017-06-07 | 株式会社キャタラー | Fuel cell electrode catalyst and method for producing the same |
| JP5948452B2 (en) * | 2015-03-02 | 2016-07-06 | 株式会社キャタラー | Method for producing supported catalyst for fuel cell |
| JP2019042662A (en) * | 2017-08-31 | 2019-03-22 | エヌ・イーケムキャット株式会社 | Manufacturing method of platinum catalyst |
| JP7178127B1 (en) | 2021-07-01 | 2022-11-25 | 石福金属興業株式会社 | METHOD FOR MANUFACTURING FUEL CELL ELECTROCATALYST |
-
2004
- 2004-04-26 JP JP2004129858A patent/JP4315857B2/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10189011B2 (en) | 2016-09-15 | 2019-01-29 | Toyota Jidosha Kabushiki Kaisha | Exhaust gas purifying catalyst and method for producing the same |
| DE102023108096A1 (en) | 2022-04-28 | 2023-11-02 | Cataler Corporation | CATALYST FOR FUEL CELL |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2005306700A (en) | 2005-11-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5761917B2 (en) | Bifunctional catalysts for selective ammonia oxidation | |
| JP5047114B2 (en) | Method for producing powder containing cerium oxide | |
| DE112013004202B4 (en) | Exhaust gas purification catalyst | |
| KR101571659B1 (en) | Base metal and base metal modified diesel oxidation catalysts | |
| WO1997043214A1 (en) | Cerium oxide and zirconium oxide based composition, method of preparation and utilisation in catalysis | |
| US20120171097A1 (en) | Catalyst for treating exhaust gases, method for producing the same, and method for treating exhaust gases | |
| EP3444030B1 (en) | Exhaust gas purification system | |
| JP2004358463A (en) | Method for manufacturing palladium three way catalyst of double layered coating structure | |
| RU2621679C2 (en) | Catalyst for exhaust gas cleaning and method for exhaust gas cleaning with the use of the specified catalyst | |
| WO2012005375A1 (en) | Exhaust gas purifying catalyst, and method for producing same | |
| JP4315857B2 (en) | Platinum solution and method for producing catalyst using the same | |
| JP2024501748A (en) | Three-way catalyst supporting noble metal in single atomic state, preparation method and use thereof | |
| CN107824185B (en) | Exhaust gas purifying catalyst and method for producing same | |
| JP2015174023A (en) | Catalyst for exhaust gas purification | |
| JP4381071B2 (en) | Method for producing exhaust gas treatment catalyst | |
| US7745371B2 (en) | Exhaust gas purifying catalyst, metal oxide particle and production process thereof | |
| EP3078416B1 (en) | Exhaust gas purification catalyst and exhaust gas purification catalyst structure | |
| WO2012077510A1 (en) | Production method for exhaust gas-purifying catalyst and motor vehicle | |
| EP2244983B1 (en) | Composition based on zirconium oxide, yttrium oxide and tungsten oxide, method of preparation and use as catalyst or catalyst support | |
| JP2006298759A (en) | Catalyst for use in purification of exhaust gas | |
| JP5375595B2 (en) | Exhaust gas purification catalyst carrier and exhaust gas purification catalyst using the same | |
| JP7213822B2 (en) | Exhaust gas purification composition | |
| JPH11217220A (en) | Compound oxide, its production and exhaust gas-cleaning catalyst using the same | |
| JP7241091B2 (en) | Exhaust gas purifying catalyst for diesel engine, method for producing the same, and method for purifying exhaust gas using the same | |
| JP6549858B2 (en) | Exhaust gas purification three-way catalyst |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20070326 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20090417 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20090421 |
|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20090519 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 4315857 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120529 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120529 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130529 Year of fee payment: 4 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20140529 Year of fee payment: 5 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| EXPY | Cancellation because of completion of term |