JP3093119B2 - Method for producing honeycomb structured catalyst for exhaust gas purification - Google Patents
Method for producing honeycomb structured catalyst for exhaust gas purificationInfo
- Publication number
- JP3093119B2 JP3093119B2 JP06304204A JP30420494A JP3093119B2 JP 3093119 B2 JP3093119 B2 JP 3093119B2 JP 06304204 A JP06304204 A JP 06304204A JP 30420494 A JP30420494 A JP 30420494A JP 3093119 B2 JP3093119 B2 JP 3093119B2
- Authority
- JP
- Japan
- Prior art keywords
- catalyst
- honeycomb structure
- exhaust gas
- weight
- silver
- 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 - Fee Related
Links
- 239000003054 catalyst Substances 0.000 title claims description 127
- 238000004519 manufacturing process Methods 0.000 title claims description 16
- 238000000746 purification Methods 0.000 title claims description 5
- 239000002002 slurry Substances 0.000 claims description 53
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 43
- 239000000835 fiber Substances 0.000 claims description 36
- 238000000576 coating method Methods 0.000 claims description 31
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims description 30
- 239000011248 coating agent Substances 0.000 claims description 27
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 22
- 239000000377 silicon dioxide Substances 0.000 claims description 21
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 claims description 20
- 229910052709 silver Inorganic materials 0.000 claims description 20
- 239000004332 silver Substances 0.000 claims description 20
- 239000003795 chemical substances by application Substances 0.000 claims description 17
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims description 16
- 239000000919 ceramic Substances 0.000 claims description 15
- WFDIJRYMOXRFFG-UHFFFAOYSA-N acetic acid anhydride Natural products CC(=O)OC(C)=O WFDIJRYMOXRFFG-UHFFFAOYSA-N 0.000 claims description 12
- 239000003638 chemical reducing agent Substances 0.000 claims description 7
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 claims description 5
- 229940100890 silver compound Drugs 0.000 claims description 5
- 150000003379 silver compounds Chemical class 0.000 claims description 5
- 239000004480 active ingredient Substances 0.000 claims description 4
- 150000001447 alkali salts Chemical class 0.000 claims description 3
- 210000004027 cell Anatomy 0.000 description 25
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 20
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 18
- SQGYOTSLMSWVJD-UHFFFAOYSA-N silver(1+) nitrate Chemical compound [Ag+].[O-]N(=O)=O SQGYOTSLMSWVJD-UHFFFAOYSA-N 0.000 description 14
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical compound [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 description 10
- 239000007789 gas Substances 0.000 description 10
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 9
- 239000007864 aqueous solution Substances 0.000 description 8
- 239000002245 particle Substances 0.000 description 8
- 238000001035 drying Methods 0.000 description 7
- 238000000034 method Methods 0.000 description 7
- 229910001961 silver nitrate Inorganic materials 0.000 description 7
- 229910021607 Silver chloride Inorganic materials 0.000 description 6
- 230000032683 aging Effects 0.000 description 6
- 239000007788 liquid Substances 0.000 description 6
- 239000000203 mixture Substances 0.000 description 6
- HKZLPVFGJNLROG-UHFFFAOYSA-M silver monochloride Chemical compound [Cl-].[Ag+] HKZLPVFGJNLROG-UHFFFAOYSA-M 0.000 description 6
- 239000007787 solid Substances 0.000 description 6
- 235000019270 ammonium chloride Nutrition 0.000 description 5
- 238000001354 calcination Methods 0.000 description 5
- 239000010408 film Substances 0.000 description 5
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 4
- 238000002485 combustion reaction Methods 0.000 description 4
- 238000001914 filtration Methods 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 4
- SCVFZCLFOSHCOH-UHFFFAOYSA-M potassium acetate Chemical compound [K+].CC([O-])=O SCVFZCLFOSHCOH-UHFFFAOYSA-M 0.000 description 4
- 239000000843 powder Substances 0.000 description 4
- 238000001694 spray drying Methods 0.000 description 4
- 238000005406 washing Methods 0.000 description 4
- ZXSQEZNORDWBGZ-UHFFFAOYSA-N 1,3-dihydropyrrolo[2,3-b]pyridin-2-one Chemical compound C1=CN=C2NC(=O)CC2=C1 ZXSQEZNORDWBGZ-UHFFFAOYSA-N 0.000 description 3
- ZZBAGJPKGRJIJH-UHFFFAOYSA-N 7h-purine-2-carbaldehyde Chemical compound O=CC1=NC=C2NC=NC2=N1 ZZBAGJPKGRJIJH-UHFFFAOYSA-N 0.000 description 3
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 3
- 241000640882 Condea Species 0.000 description 3
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- LKZMBDSASOBTPN-UHFFFAOYSA-L silver carbonate Substances [Ag].[O-]C([O-])=O LKZMBDSASOBTPN-UHFFFAOYSA-L 0.000 description 3
- 229910001958 silver carbonate Inorganic materials 0.000 description 3
- 238000003756 stirring Methods 0.000 description 3
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
- 229910021536 Zeolite Inorganic materials 0.000 description 2
- 239000000460 chlorine Substances 0.000 description 2
- 239000002131 composite material Substances 0.000 description 2
- 229910052878 cordierite Inorganic materials 0.000 description 2
- JSKIRARMQDRGJZ-UHFFFAOYSA-N dimagnesium dioxido-bis[(1-oxido-3-oxo-2,4,6,8,9-pentaoxa-1,3-disila-5,7-dialuminabicyclo[3.3.1]nonan-7-yl)oxy]silane Chemical compound [Mg++].[Mg++].[O-][Si]([O-])(O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2)O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2 JSKIRARMQDRGJZ-UHFFFAOYSA-N 0.000 description 2
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 235000011056 potassium acetate Nutrition 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- NDVLTYZPCACLMA-UHFFFAOYSA-N silver oxide Chemical compound [O-2].[Ag+].[Ag+] NDVLTYZPCACLMA-UHFFFAOYSA-N 0.000 description 2
- 229910000029 sodium carbonate Inorganic materials 0.000 description 2
- 239000007921 spray Substances 0.000 description 2
- 239000010409 thin film Substances 0.000 description 2
- 239000010457 zeolite Substances 0.000 description 2
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N 2-Propenoic acid Natural products OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- ODINCKMPIJJUCX-UHFFFAOYSA-N Calcium oxide Chemical compound [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 1
- FEWJPZIEWOKRBE-JCYAYHJZSA-N Dextrotartaric acid Chemical compound OC(=O)[C@H](O)[C@@H](O)C(O)=O FEWJPZIEWOKRBE-JCYAYHJZSA-N 0.000 description 1
- 229910004298 SiO 2 Inorganic materials 0.000 description 1
- VMHLLURERBWHNL-UHFFFAOYSA-M Sodium acetate Chemical compound [Na+].CC([O-])=O VMHLLURERBWHNL-UHFFFAOYSA-M 0.000 description 1
- FEWJPZIEWOKRBE-UHFFFAOYSA-N Tartaric acid Natural products [H+].[H+].[O-]C(=O)C(O)C(O)C([O-])=O FEWJPZIEWOKRBE-UHFFFAOYSA-N 0.000 description 1
- 229910010413 TiO 2 Inorganic materials 0.000 description 1
- 238000003915 air pollution Methods 0.000 description 1
- 239000002519 antifouling agent Substances 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 239000000292 calcium oxide Substances 0.000 description 1
- 235000012255 calcium oxide Nutrition 0.000 description 1
- 150000001732 carboxylic acid derivatives Chemical class 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 150000001805 chlorine compounds Chemical class 0.000 description 1
- 239000006255 coating slurry Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- KZHJGOXRZJKJNY-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Si]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O KZHJGOXRZJKJNY-UHFFFAOYSA-N 0.000 description 1
- 239000002657 fibrous material Substances 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 239000003779 heat-resistant material Substances 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 229910052863 mullite Inorganic materials 0.000 description 1
- 235000006408 oxalic acid Nutrition 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- ADZWSOLPGZMUMY-UHFFFAOYSA-M silver bromide Chemical compound [Ag]Br ADZWSOLPGZMUMY-UHFFFAOYSA-M 0.000 description 1
- -1 silver halide Chemical class 0.000 description 1
- 229910001923 silver oxide Inorganic materials 0.000 description 1
- FJOLTQXXWSRAIX-UHFFFAOYSA-K silver phosphate Chemical compound [Ag+].[Ag+].[Ag+].[O-]P([O-])([O-])=O FJOLTQXXWSRAIX-UHFFFAOYSA-K 0.000 description 1
- 229940019931 silver phosphate Drugs 0.000 description 1
- 229910000161 silver phosphate Inorganic materials 0.000 description 1
- YPNVIBVEFVRZPJ-UHFFFAOYSA-L silver sulfate Chemical compound [Ag+].[Ag+].[O-]S([O-])(=O)=O YPNVIBVEFVRZPJ-UHFFFAOYSA-L 0.000 description 1
- 229910000367 silver sulfate Inorganic materials 0.000 description 1
- 239000001632 sodium acetate Substances 0.000 description 1
- 235000017281 sodium acetate Nutrition 0.000 description 1
- 239000011780 sodium chloride Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 235000002906 tartaric acid Nutrition 0.000 description 1
- 239000011975 tartaric acid Substances 0.000 description 1
- 238000009210 therapy by ultrasound Methods 0.000 description 1
- 238000005979 thermal decomposition reaction Methods 0.000 description 1
Description
【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION
【０００１】[0001]
【産業上の利用分野】本発明は内燃機関からの酸素濃度
の高い排ガス中に含まれる窒素酸化物（ＮＯx）を低減
する排ガス浄化用ハニカム構造体触媒の製造方法に関
し、さらに詳しくはリーンバーンガソリンエンジン、デ
ィーゼルエンジン等の内燃機関からの排ガス中のＮＯx
を低減する浄化用ハニカム構造体触媒の製造方法に関す
るものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a honeycomb structure catalyst for purifying exhaust gas, which reduces nitrogen oxides (NO x ) contained in exhaust gas having a high oxygen concentration from an internal combustion engine, and more particularly to a lean burn method. NO x in exhaust gas from internal combustion engines such as gasoline engines and diesel engines
The present invention relates to a method for producing a purifying honeycomb structure catalyst for reducing a catalyst.
【０００２】[0002]
【従来の技術】大気汚染防止を目的として、近年、リー
ンバーンガソリンエンジン自動車およびディーゼルエン
ジンを搭載した自動車またはコージェネレーション発電
機等の内燃機関からの排ガスのように、高い酸素濃度の
内燃機関からの排ガスを浄化することが急務となってい
る。2. Description of the Related Art For the purpose of preventing air pollution, in recent years, high-oxygen-concentration internal combustion engines such as automobiles equipped with lean-burn gasoline engines and diesel engines or internal combustion engines such as cogeneration generators have been developed. Purification of exhaust gas is urgently needed.
【０００３】こうした用途の触媒としては、非常に高い
ガス空間速度で使用されるために圧力損失を可能な限り
低減する必要があり、一般にガス流通方向に形成された
多数の直通管状通路（セルと呼ぶ）を有するコージェラ
イトあるいはムライト等からなるセラミック製もしくは
複数の金属からなる金属製のハニカム構造体各セルの表
面に、所望の触媒を薄膜状に塗布したハニカム構造体触
媒が使用されている。[0003] As a catalyst for such an application, it is necessary to reduce the pressure loss as much as possible because it is used at a very high gas space velocity. In general, a large number of direct tubular passages (cells and cells) formed in the gas flow direction are required. The honeycomb structure catalyst is used in which a desired catalyst is applied in the form of a thin film on the surface of each cell made of ceramic or metal made of a plurality of metals, such as cordierite or mullite.
【０００４】こうした触媒は基材としてのハニカム構造
体の各セル表面に所望の触媒成分を薄膜状に塗布するこ
とによって製造される。ハニカム構造体の各セルに触媒
成分を塗布する方法としては、粉末状のアルミナ、シリ
カ、ゼオライト、シリカ・アルミナ、チタニア、ジルコ
ニア等から選択された酸化物もしくは複合酸化物である
多孔質担体に、有効成分を担持し、触媒とし、これをア
ルミナゾル、シリカゾル等の適当な固着剤と混合して水
性スラリーとなし、このスラリーに前記のハニカム構造
体をディッピングした後、セル内部の余分なスラリーを
加圧空気で除去し、乾燥後、熱処理（焼成）して調製さ
れる。[0004] Such a catalyst is produced by applying a desired catalyst component in the form of a thin film on the surface of each cell of a honeycomb structure as a substrate. As a method of applying the catalyst component to each cell of the honeycomb structure, powdery alumina, silica, zeolite, silica-alumina, titania, a porous carrier that is an oxide or a composite oxide selected from zirconia, The active ingredient is supported and used as a catalyst. The catalyst is mixed with an appropriate fixing agent such as alumina sol or silica sol to form an aqueous slurry. After the honeycomb structure is dipped in the slurry, the excess slurry inside the cell is added. It is prepared by removing it with pressurized air, drying and then heat-treating (firing).
【０００５】金属や金属酸化物を有効成分とし、これを
アルミナ、シリカ等の多孔質担体上に担持した触媒をハ
ニカム構造体のセル表面にウォッシュコートによって塗
布し、各種の反応用のハニカム構造体触媒を製造する場
合、該ハニカム構造体触媒に所望の反応特性と寿命を付
与するために、可能な限り多量の触媒成分をハニカム構
造体のセル表面に塗布しなければならない。[0005] A catalyst having a metal or metal oxide as an active ingredient, which is supported on a porous carrier such as alumina or silica, is applied to the cell surface of the honeycomb structure by wash coating to form a honeycomb structure for various reactions. When manufacturing a catalyst, as much catalyst component as possible must be applied to the cell surface of the honeycomb structure in order to impart desired reaction characteristics and life to the honeycomb structure catalyst.
【０００６】従来の方法によって多量の触媒成分を塗布
する場合には、使用するコート用水性スラリーの粘度と
安定性の問題から該スラリー中の触媒成分濃度には制限
があり、コート回数が著しく増加して製造コストが上昇
するという経済性の面で問題があった。また、多量の触
媒成分を塗布した場合には、各セル表面に塗布される触
媒成分の膜厚が塗布量に応じてその厚さが増加する。膜
厚の増加は触媒成分が塗布されたハニカム構造体触媒の
調製における熱処理工程または反応に使用されている状
態において、繰り返し熱衝撃を受けることから塗布膜に
歪みが発生し、亀裂が生じることによって塗布された触
媒成分が剥離しやすくなり、結果として反応特性と寿命
が低下するという問題があった。When a large amount of a catalyst component is applied by a conventional method, the concentration of the catalyst component in the aqueous slurry for coating used is limited due to the problems of viscosity and stability of the slurry. As a result, there is a problem in terms of economic efficiency that the production cost increases. Further, when a large amount of the catalyst component is applied, the thickness of the catalyst component applied to the surface of each cell increases according to the applied amount. The increase in film thickness is caused by the repeated application of thermal shock during the heat treatment process or the reaction in the preparation of the honeycomb structure catalyst coated with the catalyst component, resulting in the coating film being distorted and cracking. There has been a problem that the applied catalyst component is easily peeled off, and as a result, the reaction characteristics and the life are reduced.
【０００７】[0007]
【発明が解決しようとする課題】本発明は、こうした従
来技術の課題を解決し、多量の触媒成分を少ないコート
回数で経済的に塗布し、かつ多量の触媒成分の各セル表
面への付着によってコート膜厚が増加しても触媒成分の
剥離、脱落を最小限に抑制できるハニカム構造体触媒の
製造方法を提供することを目的とする。SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, and economically applies a large amount of a catalyst component with a small number of coats, and adheres a large amount of the catalyst component to each cell surface. It is an object of the present invention to provide a method for manufacturing a honeycomb structured catalyst which can minimize peeling and falling off of a catalyst component even when a coating film thickness increases.
【０００８】[0008]
【課題を解決するための手段】本発明の上記目的は、コ
ート用水性スラリーに剥離防止剤として特定の径を有す
るシリカ系セラミック繊維を含有させることによって達
成される。The above object of the present invention is achieved by incorporating a silica-based ceramic fiber having a specific diameter as an anti-peeling agent into an aqueous slurry for coating.
【０００９】すなわち、本発明は、ガスの流通方向に形
成された多数のセルを有するハニカム構造体の表面に、
触媒を固着させてなる排ガス浄化用ハニカム構造体触媒
の製造方法であって、該触媒を水性スラリー化してハニ
カム構造体表面にコートして固着させるに際し、該触媒
とアルミナゾル、シリカゾル、チタニアゾル、ジルコニ
アゾルから選択された少なくとも１種のゾルからなる固
着剤と酢酸、無水酢酸、酢酸のアルカリ塩から選択され
た少なくとも１種の粘度低下剤、および該触媒のメジア
ン径の０．９５〜１２．５倍の繊維径を有するシリカ系
セラミック繊維からなる剥離防止剤とを含有するコート
用水性スラリーを該ハニカム構造体表面に塗布し、該触
媒をハニカム構造体表面に固着させ、次いで焼成（熱処
理）することを特徴とする排ガス浄化用ハニカム構造体
触媒の製造方法にある。That is, according to the present invention, a honeycomb structure having a large number of cells formed in a gas flow direction is provided on a surface of the honeycomb structure.
A method for producing a honeycomb structure catalyst for purifying exhaust gas, comprising fixing a catalyst, wherein the catalyst is converted into an aqueous slurry, coated on the surface of the honeycomb structure and fixed, and the catalyst is mixed with an alumina sol, a silica sol, a titania sol, and a zirconia sol. A binder comprising at least one sol selected from the group consisting of acetic acid, acetic anhydride, and an alkali salt of acetic acid; and 0.95 to 12.5 times the median diameter of the catalyst. A coating aqueous slurry containing a silica-based ceramic fiber having a fiber diameter of 3 mm and an anti-peeling agent is applied to the surface of the honeycomb structure, the catalyst is fixed to the surface of the honeycomb structure, and then fired (heat treated). A method for producing a catalyst for a honeycomb structure for purifying exhaust gas, the method comprising:
【００１０】本発明に用いられる触媒成分は特に制限さ
れないが、好ましくは銀または銀化合物を含有する少な
くとも１種以上の活性成分が多孔質耐熱性担体上に担持
されたものである。銀化合物としては酸化銀や塩化銀、
臭化銀といったハロゲン化銀や炭酸銀、硫酸銀、燐酸銀
等が例示される。触媒特性からこれらの活性成分の量は
銀に換算して好ましくは０．０１〜２０．０重量％、さ
らに好ましくは０．０５〜１５．０重量％含有すること
が望ましい。銀に換算した量が０．０１重量％未満では
窒素酸化物の除去効率が小さく、２０．０重量％を超え
た場合には、高温での窒素酸化物の除去効率が劣ったも
のとなる。The catalyst component used in the present invention is not particularly limited. Preferably, at least one active component containing silver or a silver compound is supported on a porous heat-resistant carrier. As silver compounds, silver oxide, silver chloride,
Examples thereof include silver halide such as silver bromide, silver carbonate, silver sulfate, and silver phosphate. From the viewpoint of catalytic properties, the amount of these active ingredients is preferably 0.01 to 20.0% by weight, more preferably 0.05 to 15.0% by weight, as calculated as silver. If the amount in terms of silver is less than 0.01% by weight, the removal efficiency of nitrogen oxides is small, and if it exceeds 20.0% by weight, the removal efficiency of nitrogen oxides at high temperatures is inferior.
【００１１】多孔質耐熱性担体としては、シリカ、アル
ミナ、チタニア、ジルコニア等の酸化物あるいはシリカ
・アルミナ、ゼオライトといったこれらの複合酸化物等
が挙げられる。この耐熱性多孔質担体は通常酸化物の状
態で使用されるが、特に酸化物に限定されるものではな
く、熱分解を経ていない水和酸化物上に前記の銀もしく
は銀化合物を担持し、最終的に熱処理して触媒となすこ
ともできる。Examples of the porous heat-resistant carrier include oxides such as silica, alumina, titania and zirconia, and composite oxides thereof such as silica-alumina and zeolite. This heat-resistant porous carrier is usually used in the form of an oxide, but is not particularly limited to oxides, and supports the silver or silver compound on a hydrated oxide that has not undergone thermal decomposition, Finally, heat treatment can be performed to form a catalyst.
【００１２】耐熱性多孔質担体上への前記銀もしくは銀
化合物の担持方法は特に限定されるものではなく、任意
の方法でよいが、例えば硝酸銀水溶液に前記の担体粉末
を懸濁させた後に、塩化アンモニウム、塩化ナトリウム
等の水溶性塩素化合物の水溶液を添加し、担体上に塩化
銀として担持させた後、熱処理して触媒となすことがで
きる。The method for supporting the silver or silver compound on the heat-resistant porous carrier is not particularly limited, and may be any method. For example, after suspending the carrier powder in an aqueous silver nitrate solution, An aqueous solution of a water-soluble chlorine compound such as ammonium chloride, sodium chloride or the like is added, supported on a carrier as silver chloride, and then heat-treated to form a catalyst.
【００１３】本発明ではこのようにして得られた触媒を
コート用水性スラリーとする。このコート用水性スラリ
ーには、触媒に加えて固着剤と粘度低下剤、さらに剥離
防止剤とを含有する。In the present invention, the catalyst thus obtained is used as an aqueous slurry for coating. The aqueous slurry for coating contains, in addition to the catalyst, a fixing agent, a viscosity reducing agent, and an anti-peeling agent.
【００１４】固着剤はコート用スラリーでハニカム構造
体の各セル表面にウォッシュコートした後、熱処理（焼
成）によって触媒の粒子をハニカム構造体のセル表面に
強固に固着させるためのものであって、具体的にはアル
ミナゾル、シリカゾル、チタニアゾル、ジルコニアゾル
の中から選択された少なくとも１種以上のゾルから選択
される。The fixing agent is used for wash-coating each cell surface of the honeycomb structure with a coating slurry, and then, by heat treatment (calcination), for firmly fixing the catalyst particles to the cell surface of the honeycomb structure. Specifically, it is selected from at least one or more sols selected from alumina sol, silica sol, titania sol, and zirconia sol.
【００１５】また、水性スラリーの粘度を低下させるた
めの粘度低下剤としては、酢酸、無水酢酸、もしくは酢
酸カリウム、酢酸ナトリウム等の酢酸のアルカリ塩の少
なくとも１種以上が選択されるが、この他に、シュウ
酸、酒石酸、アクリル酸等のカルボン酸もしくはその誘
導体を使用してもよい。粘度低下剤の含有量は水性スラ
リー中の触媒重量に対して、好ましくは０．５〜１５．
０重量％、さらに好ましくは１．０〜１２．０重量％で
ある。粘度低下剤の含有量が０．５重量％未満では粘度
低下効果を発現できず、１５．０重量％を超えると触媒
の担体成分が溶解し、触媒性能を劣化させる恐れを有す
るのみならず、過剰であるために経済性に劣る。As the viscosity reducing agent for lowering the viscosity of the aqueous slurry, at least one of acetic acid, acetic anhydride, or an alkali salt of acetic acid such as potassium acetate or sodium acetate is selected. Alternatively, a carboxylic acid such as oxalic acid, tartaric acid or acrylic acid or a derivative thereof may be used. The content of the viscosity reducing agent is preferably from 0.5 to 15% based on the weight of the catalyst in the aqueous slurry.
0% by weight, more preferably 1.0 to 12.0% by weight. When the content of the viscosity reducing agent is less than 0.5% by weight, the effect of lowering the viscosity cannot be exhibited. The economy is poor because of excess.
【００１６】上記した触媒成分、固着剤、粘度低下剤を
含有した水性スラリーは撹拌、混合され、さらに水性ス
ラリー中の触媒は湿式粉砕機で粉砕され、触媒のメジア
ン径を好ましくは０．１〜１５．０μｍ、さらに好まし
くは０．５〜１２．０μｍとされる。触媒のメジアン径
が０．１μｍ未満ではスラリー粘度が上昇し、結果とし
てハニカム構造体への触媒固着の不均一性、ハニカム構
造体触媒からの触媒の剥離率の増加を招く。他方、触媒
メジアン径が１５．０μｍを超えると水性スラリー中の
触媒の沈降が著しく、安定性に欠ける。The aqueous slurry containing the above-mentioned catalyst component, fixing agent, and viscosity reducing agent is stirred and mixed, and the catalyst in the aqueous slurry is further ground by a wet mill, and the median diameter of the catalyst is preferably 0.1 to 0.1. It is 15.0 μm, more preferably 0.5 to 12.0 μm. If the median diameter of the catalyst is less than 0.1 μm, the slurry viscosity increases, resulting in non-uniform fixation of the catalyst to the honeycomb structure and an increase in the rate of separation of the catalyst from the honeycomb structure catalyst. On the other hand, when the median diameter of the catalyst exceeds 15.0 μm, the catalyst in the aqueous slurry is significantly settled and lacks stability.
【００１７】上記のように湿式粉砕して調製された水性
スラリーは、最終的に剥離防止剤を加えてコート用水性
スラリーが完成される。剥離防止剤はシリカまたはシリ
カとアルミナ、カルシア等からなるシリカ系セラミック
繊維であり、耐熱性の繊維状物質であるが、成分は特に
限定されるものではなく、シリカを主成分とする耐熱性
のあるセラミック繊維物質であればよい。該剥離防止剤
（シリカ系セラミック繊維）の繊維径は好ましくは６．
０〜１５．０μｍ、さらに好ましくは８．０〜１３．０
μｍである。また平均繊維長さは好ましくは３０〜３０
０μｍ、さらに好ましくは６０〜２００μｍである。繊
維径が６．０μｍ未満では繊維径が細すぎることから強
度上に問題があり、水性スラリーの調製時に所望の繊維
長を維持できないという欠点がある。他方、繊維径が１
５．０μｍを超えると、水性スラリー中の触媒成分粒子
径より著しく大きくなることにより、触媒成分粒子と剥
離防止剤との均一混合が困難となる。また、平均繊維長
さが３０μｍ未満では、コート膜に発生する亀裂防止に
十分な効果が得られず、平均繊維長さが３００μｍを超
えると水性スラリーをハニカム構造体の各セルにウォッ
シュコートする場合に、セルプラグを発生し易くなるの
で好ましくない。前記のような繊維径と長さを持つ剥離
防止剤は、水性スラリー中の触媒成分に対して１．０〜
２０．０重量％、さらに好ましくは２．０〜１０．０重
量％添加される。添加量が１．０重量％未満では剥離防
止効果が減少する。また、添加量が２０．０重量％を超
えると経済性の面で劣る。The aqueous slurry prepared by wet pulverization as described above is finally added with an anti-peeling agent to complete the aqueous slurry for coating. The anti-peeling agent is a silica-based ceramic fiber made of silica or silica and alumina, calcia, etc., and is a heat-resistant fibrous substance, but the component is not particularly limited, and a heat-resistant material containing silica as a main component is used. Any ceramic fiber material may be used. The fiber diameter of the anti-peeling agent (silica-based ceramic fiber) is preferably 6.
0 to 15.0 μm, more preferably 8.0 to 13.0.
μm. The average fiber length is preferably 30 to 30.
0 μm, more preferably 60 to 200 μm. If the fiber diameter is less than 6.0 μm, there is a problem in strength because the fiber diameter is too small, and there is a drawback that a desired fiber length cannot be maintained during preparation of the aqueous slurry. On the other hand, if the fiber diameter is 1
If it exceeds 5.0 μm, it will be significantly larger than the particle diameter of the catalyst component in the aqueous slurry, making it difficult to uniformly mix the catalyst component particles and the anti-stripping agent. When the average fiber length is less than 30 μm, a sufficient effect for preventing cracks generated in the coating film cannot be obtained, and when the average fiber length exceeds 300 μm, the aqueous slurry is wash-coated on each cell of the honeycomb structure. In addition, cell plugs are easily generated, which is not preferable. The antifouling agent having the fiber diameter and the length as described above is 1.0 to 1.0 with respect to the catalyst component in the aqueous slurry.
20.0% by weight, more preferably 2.0 to 10.0% by weight is added. If the amount is less than 1.0% by weight, the effect of preventing peeling is reduced. On the other hand, if the amount exceeds 20.0% by weight, economic efficiency is poor.
【００１８】本発明によるハニカム構造体触媒の製造
は、上記のようにして調製されたコート用水性スラリー
に、ハニカム構造体をディップして引き上げた後、ハニ
カム構造体の各セル内部の余分なスラリーを加圧空気に
よって除去する（ウォッシュコート）。In the production of the honeycomb structured catalyst according to the present invention, after the honeycomb structured body is dipped and pulled up into the aqueous slurry for coating prepared as described above, the excess slurry inside each cell of the honeycomb structured body is prepared. Is removed by pressurized air (wash coat).
【００１９】さらに乾燥した後、ウォッシュコートを繰
り返す。こうして所望の触媒成分量をハニカム構造体の
セル表面に固着させ、最終的に熱処理（焼成）して触媒
成分が強固に固着されたハニカム構造体触媒を得る。After further drying, the washcoat is repeated. In this way, a desired amount of the catalyst component is fixed to the cell surface of the honeycomb structure, and finally heat treatment (calcination) is performed to obtain a honeycomb structure catalyst in which the catalyst component is firmly fixed.
【００２０】[0020]
【実施例】以下、本発明を実施例等によってさらに詳細
に説明する。The present invention will be described below in more detail with reference to examples.
【００２１】実施例１ ビーカーに純水２５０ｇを採り、硝酸銀４．１４ｇを添
加して溶解した。４０℃のこの液に粉末アルミナ水和酸
化物（商品名：Ｐｕｒａｌ ＳＢ、Ｃｏｎｄｅａ社製）
１００ｇを加えて撹拌、懸濁し、別に調製した塩化アン
モニウム１．４ｇを純水５０ｇに溶解した水溶液を１５
分間で添加してアルミナ水和酸化物粒子表面に塩化銀を
担持させた。６０分間熟成した後、スプレードライし、
得られた粉末をさらに３９０℃で６０分間焼成すること
により銀に換算して２．９７重量％を含有する銀／アル
ミナ触媒を得た。 Example 1 250 g of pure water was placed in a beaker, and 4.14 g of silver nitrate was added and dissolved. Powdered alumina hydrated oxide (trade name: Pural SB, manufactured by Condea) was added to this liquid at 40 ° C.
100 g was added thereto, and the mixture was stirred and suspended. An aqueous solution prepared by dissolving 1.4 g of separately prepared ammonium chloride in 50 g of pure water was added to 15 g of an aqueous solution.
Min. To support silver chloride on the surface of the alumina hydrated oxide particles. After aging for 60 minutes, spray dry,
The obtained powder was further calcined at 390 ° C. for 60 minutes to obtain a silver / alumina catalyst containing 2.97% by weight in terms of silver.
【００２２】次に、この触媒４５ｇと純水１００ｇ、酢
酸２．２５ｇおよびアルミナゾル（Ａｌ2Ｏ3含有率１
０．５重量％）２１．４ｇを加えて撹拌、混合し、湿式
粉砕機を用いて触媒のメジアン径を８．５μｍとし、固
形分濃度２８．０重量％の水性スラリーを調製した。こ
のスラリーの粘度を測定したところ１５ｃｐｓであっ
た。湿式粉砕したスラリーに剥離防止剤として繊維径１
０μｍ、平均繊維長さ１００μｍであるシリカ系セラミ
ック繊維を触媒重量に対して６．０重量部添加し撹拌、
混合した。Next, 45 g of this catalyst, 100 g of pure water, 2.25 g of acetic acid and alumina sol (Al 2 O 3
0.5% by weight), stirred and mixed, and a wet pulverizer was used to adjust the median diameter of the catalyst to 8.5 μm to prepare an aqueous slurry having a solids concentration of 28.0% by weight. The viscosity of this slurry was measured and found to be 15 cps. Fiber diameter of 1 as wet-milled slurry
0 μm, 6.0 parts by weight of a silica-based ceramic fiber having an average fiber length of 100 μm with respect to the catalyst weight was added and stirred,
Mixed.
【００２３】このスラリーに直径２０ｍｍ、高さ１６ｍ
ｍ、セル数２００セル／平方インチのコージェライト製
ハニカム構造体をディップし、引き上げた後に加圧空気
によってセル内の余分なスラリーを除去した。５０℃で
５分間予備乾燥した後、１９０〜２００℃で乾燥した触
媒成分を固着させ、この操作を２回繰り返した。最終的
に６００℃で９０分間空気中で焼成しハニカム構造体触
媒を得た。得られたハニカム構造体触媒は１９７ｇ／Ｌ
の触媒成分がコートされた。The slurry has a diameter of 20 mm and a height of 16 m.
A cordierite honeycomb structure having a cell number of 200 cells / square inch was dipped, pulled up, and then pressurized air was used to remove excess slurry in the cells. After preliminarily drying at 50 ° C for 5 minutes, the catalyst component dried at 190 to 200 ° C was fixed, and this operation was repeated twice. Finally, it was fired at 600 ° C. for 90 minutes in the air to obtain a honeycomb structured catalyst. The obtained honeycomb structure catalyst was 197 g / L.
Of the catalyst component was coated.
【００２４】剥離試験は次のようにして実施した。ハニ
カム構造体触媒を１８０℃で２時間乾燥してデシケータ
中で冷却し、ハニカム構造体触媒の重量（Ｗ1）を測定
し、このハニカム構造体触媒を８００℃に維持した電気
炉に入れ１５分間保持、ただちに室温下に１５分間放置
した。この操作を２回繰り返した後、ハニカム構造体触
媒を水中に入れ、２８ＫＨｚの超音波処理を１０分間実
施した。１８０℃２時間乾燥してデシケータ中で冷却し
た後の受領（Ｗ2）を測定し、剥離率を下記の式から求
めた。下記の式においてＷ0はウォッシュコート前のハ
ニカム構造体のみの重量である。The peel test was performed as follows. The honeycomb structured catalyst was dried at 180 ° C. for 2 hours and cooled in a desiccator, the weight (W 1 ) of the honeycomb structured catalyst was measured, and the honeycomb structured catalyst was placed in an electric furnace maintained at 800 ° C. for 15 minutes. Hold and immediately left at room temperature for 15 minutes. After repeating this operation twice, the honeycomb structure catalyst was put into water, and ultrasonic treatment at 28 KHz was performed for 10 minutes. Receiving (W 2 ) after drying at 180 ° C. for 2 hours and cooling in a desiccator was measured, and the peeling rate was determined from the following equation. In the following formula, W 0 is the weight of only the honeycomb structure before wash coating.
【００２５】剥離率（％）＝｛（Ｗ1−Ｗ2）／（Ｗ1−
Ｗ0）｝×１００ このようにして得られた剥離率をコート回数、コート量
と共に表１に示す。Peeling rate (%) = ｛(W 1 −W 2 ) / (W 1 −
W 0 )｝ × 100 The peeling ratio thus obtained is shown in Table 1 together with the number of coating times and the coating amount.
【００２６】実施例２ ビーカーに純水１，０００ｇを採り、硝酸銀５．７ｇを
添加して溶解した。４０℃に維持されたこの液に、粉末
シリカ（商品名：トクシール ＵＲ、トクヤマ社製）１
００ｇを加えて撹拌、懸濁し、別に調製した塩化アンモ
ニウム２．０ｇを純水５０ｇに溶解した水溶液を１５分
間で添加してシリカ粒子表面に塩化銀を担持させた。６
０分間熟成して濾過、洗浄を繰り返した後、スプレード
ライで乾燥し、さらに３５０℃で６０分間焼成すること
により銀に換算して３．４重量％を含有する銀／シリカ
触媒を調製した。 Example 2 1,000 g of pure water was placed in a beaker, and 5.7 g of silver nitrate was added and dissolved. Powdered silica (trade name: Toksil UR, manufactured by Tokuyama Corporation) 1 was added to this liquid maintained at 40 ° C.
Then, an aqueous solution prepared by dissolving 2.0 g of ammonium chloride in 50 g of pure water was added over 15 minutes, and silver chloride was supported on the surface of the silica particles. 6
After aging for 0 minutes, repeating filtration and washing, the resultant was dried by spray drying, and further calcined at 350 ° C. for 60 minutes to prepare a silver / silica catalyst containing 3.4% by weight in terms of silver.
【００２７】次に、この触媒４５ｇ、酢酸カリウム３．
６ｇ、純水１００ｇおよびシリカゾル（ＳｉＯ2含有率
２０．５重量％）１７．６ｇを撹拌、混合し、さらに湿
式粉砕機を用いて触媒のメジアン径を６．５μｍとし、
固形分濃度３１．４重量％である水性スラリーを調製し
た。このスラリーの粘度は８５ｃｐｓであった。次いで
湿式粉砕したスラリーに剥離防止剤として繊維径８．５
μｍ、平均繊維長さ１８０μｍであるシリカ系セラミッ
ク繊維を触媒重量に対して１２．０重量部添加し、撹
拌、混合した。Next, 45 g of this catalyst and potassium acetate.
6 g, 100 g of pure water and 17.6 g of silica sol (SiO 2 content: 20.5% by weight) were stirred and mixed, and the median diameter of the catalyst was adjusted to 6.5 μm using a wet pulverizer.
An aqueous slurry having a solid concentration of 31.4% by weight was prepared. The viscosity of this slurry was 85 cps. Next, a fiber diameter of 8.5 was added to the wet-milled slurry as an anti-peeling agent.
12.0 parts by weight of a silica-based ceramic fiber having an average fiber length of 180 μm and an average fiber length of 180 μm were added, stirred, and mixed.
【００２８】この水性スラリーを実施例１に記載と同様
の方法でハニカム構造体セル表面に触媒成分を２回ウォ
ッシュコートしてハニカム構造体触媒を調製した。得ら
れたハニカム構造体触媒は１７８ｇ／Ｌの触媒成分がコ
ートされた。This aqueous slurry was wash-coated twice on the surface of the honeycomb structure cell with the catalyst component in the same manner as described in Example 1 to prepare a honeycomb structure catalyst. The obtained honeycomb structure catalyst was coated with a catalyst component of 178 g / L.
【００２９】また、実施例１と同様に剥離試験を行な
い、その剥離率をコート回数、コート量と共に表１に示
す。A peeling test was conducted in the same manner as in Example 1, and the peeling rate is shown in Table 1 together with the number of coatings and the amount of coating.
【００３０】実施例３ ビーカーに純水２５０ｇを採り、硝酸銀７．４ｇを添加
して溶解した。４０℃に維持されたこの液に、粉末チタ
ニア（商品名：Ｃ−２、石原産業社製）１００ｇを加え
て撹拌、懸濁し、別に調製した塩化アンモニウム２．８
ｇを純水５０ｇに溶解した水溶液を１５分間で添加して
チアニア粒子表面に塩化銀を担持させた。６０分間熟成
して濾過、洗浄を繰り返した後、スプレードライで乾燥
し、さらに３５０℃で６０分間焼成することにより銀に
換算して４．４重量％を含有する銀／チタニア触媒を調
製した。 Example 3 250 g of pure water was placed in a beaker, and 7.4 g of silver nitrate was added and dissolved. 100 g of powdered titania (trade name: C-2, manufactured by Ishihara Sangyo Co., Ltd.) was added to this liquid maintained at 40 ° C., and the mixture was stirred, suspended, and separately prepared with ammonium chloride 2.8.
g of pure water in 50 g of pure water was added over 15 minutes to carry silver chloride on the surface of the Tianania grains. After aging for 60 minutes, repeating filtration and washing, drying by spray drying, and calcination at 350 ° C. for 60 minutes, a silver / titania catalyst containing 4.4% by weight in terms of silver was prepared.
【００３１】次に、この触媒５０ｇ、酢酸２．５ｇ、純
水１００ｇおよびチタニアゾル（ＴｉＯ2含有率３０．
０重量％）８．３ｇを撹拌、混合し、さらに湿式粉砕機
を用いて触媒のメジアン径を１．２μｍとし、固形分濃
度３２．６重量％である水性スラリーを調製した。この
スラリーの粘度は３６ｃｐｓであった。次いで湿式粉砕
したスラリーに剥離防止剤として繊維径１２．５μｍ、
平均繊維長さ６５μｍであるシリカ系セラミック繊維を
触媒重量に対して２．０重量部添加し、撹拌、混合し
た。Next, 50 g of this catalyst, 2.5 g of acetic acid, 100 g of pure water and titania sol (TiO 2 content of 30.
(0% by weight) was stirred and mixed, and an aqueous slurry having a solids concentration of 32.6% by weight was prepared using a wet pulverizer with a catalyst having a median diameter of 1.2 μm. The viscosity of this slurry was 36 cps. Then, a fiber diameter of 12.5 μm is used as an anti-stripping agent in the wet-milled slurry,
2.0 parts by weight of a silica-based ceramic fiber having an average fiber length of 65 μm based on the weight of the catalyst was added, followed by stirring and mixing.
【００３２】この水性スラリーを実施例１に記載と同様
の方法でハニカム構造体セル表面に触媒成分を２回ウォ
ッシュコートしてハニカム構造体触媒を調製した。得ら
れたハニカム構造体触媒は２１５ｇ／Ｌの触媒成分がコ
ートされた。This aqueous slurry was wash-coated twice on the surface of the honeycomb structure cell with the catalyst component in the same manner as described in Example 1 to prepare a honeycomb structure catalyst. The obtained honeycomb structure catalyst was coated with a catalyst component of 215 g / L.
【００３３】また、実施例１と同様に剥離試験を行な
い、その剥離率をコート回数、コート量と共に表１に示
す。Further, a peeling test was conducted in the same manner as in Example 1, and the peeling rate is shown in Table 1 together with the number of coating times and the coating amount.
【００３４】実施例４ ビーカーに純水２５０ｇを採り、硝酸銀１．５９ｇを添
加して溶解した。４０℃に維持されたこの液に、粉末ジ
ルコニア（商品名：ＲＣ、第一稀元素化学工業社製）１
００ｇを加えて撹拌、懸濁し、別に調製した炭酸ナトリ
ウム０．５５ｇを純水５０ｇに溶解した水溶液を１５分
間で添加してジルコニア粒子表面に炭酸銀を担持させ
た。６０分間熟成して濾過、洗浄を繰り返した後、スプ
レードライで乾燥し、さらに４５０℃で６０分間焼成す
ることにより銀に換算して１．０重量％を含有する銀／
ジルコニア触媒を調製した。 Example 4 250 g of pure water was placed in a beaker, and 1.59 g of silver nitrate was added and dissolved. Powder zirconia (trade name: RC, manufactured by Daiichi Rare Element Chemical Co., Ltd.) 1 was added to this liquid maintained at 40 ° C.
To the resulting zirconia particles was added an aqueous solution of 0.55 g of sodium carbonate dissolved in 50 g of pure water for 15 minutes to add silver carbonate to the surface of the zirconia particles. After aging for 60 minutes, repeating filtration and washing, drying by spray drying, and calcination at 450 ° C. for 60 minutes, silver / silver containing 1.0% by weight in terms of silver /
A zirconia catalyst was prepared.
【００３５】次に、この触媒５０ｇ、無水酢酸５．５
ｇ、純水１００ｇおよびジルコニアゾル（ＺｒＯ2含有
率２５．０重量％）２２．０ｇを撹拌、混合し、さらに
湿式粉砕機を用いて触媒のメジアン径を１．０μｍと
し、固形分濃度３１．４重量％である水性スラリーを調
製した。このスラリーの粘度は４１ｃｐｓであった。次
いで湿式粉砕したスラリーに剥離防止剤として繊維径１
２．５μｍ、平均繊維長さ１８０μｍであるシリカ系セ
ラミック繊維を触媒重量に対して４．０重量部添加し、
撹拌、混合した。Next, 50 g of the catalyst and 5.5 acetic anhydride were used.
g, 100 g of pure water and 22.0 g of zirconia sol (ZrO 2 content: 25.0% by weight) were mixed and further mixed with a wet pulverizer to adjust the median diameter of the catalyst to 1.0 μm and to obtain a solid content of 31. An aqueous slurry that was 4% by weight was prepared. The viscosity of this slurry was 41 cps. Then, the wet-milled slurry was added with a fiber diameter of 1
2.5 parts by weight of a silica-based ceramic fiber having an average fiber length of 180 μm and 4.0 parts by weight based on the weight of the catalyst,
Stir and mix.
【００３６】この水性スラリーを実施例１に記載と同様
の方法でハニカム構造体セル表面に触媒成分を２回ウォ
ッシュコートしてハニカム構造体触媒を調製した。得ら
れたハニカム構造体触媒は１８５ｇ／Ｌの触媒成分がコ
ートされた。This aqueous slurry was wash-coated twice on the surface of the honeycomb structure cell with the catalyst component in the same manner as described in Example 1 to prepare a honeycomb structure catalyst. The obtained honeycomb structure catalyst was coated with a catalyst component of 185 g / L.
【００３７】また、実施例１と同様に剥離試験を行な
い、その剥離率をコート回数、コート量と共に表１に示
す。A peeling test was conducted in the same manner as in Example 1, and the peeling rate is shown in Table 1 together with the number of coating times and the coating amount.
【００３８】実施例５ ビーカーに純水２５０ｇを採り、硝酸銀１４．９ｇを添
加して溶解した。４０℃に維持されたこの液に、粉末ア
ルミナ水和酸化物（商品名：Ｐｕｒａｌ ＳＢ、Ｃｏｎ
ｄｅａ社製）１００ｇを加えて撹拌、懸濁し、別に調製
した炭酸ナトリウム５．１ｇを純水５０ｇに溶解した水
溶液を１５分間で添加してアルミナ水和酸化物粒子表面
に炭酸銀を担持させた。６０分間熟成して濾過、洗浄を
繰り返した後、スプレードライで乾燥し、さらに４５０
℃で６０分間焼成することにより銀に換算して１０．０
重量％を含有する銀／アルミナ触媒を調製した。 Example 5 250 g of pure water was placed in a beaker, and 14.9 g of silver nitrate was added and dissolved. This liquid maintained at 40 ° C. was added to powdered alumina hydrated oxide (trade names: Pural SB, Con
Dea) (100 g), stirred and suspended, and an aqueous solution prepared by dissolving 5.1 g of sodium carbonate separately in 50 g of pure water was added over 15 minutes to carry silver carbonate on the surface of the alumina hydrated oxide particles. . After aging for 60 minutes, repeating filtration and washing, drying by spray drying,
Calcination for 60 minutes at a temperature of 10.0 ° C in terms of silver.
A silver / alumina catalyst containing% by weight was prepared.
【００３９】次に、この触媒６５ｇ、酢酸２．０ｇ、純
水１００ｇおよびアルミナゾル（Ａｌ2Ｏ3含有率１０．
５重量％）１８．６ｇを撹拌、混合し、さらに湿式粉砕
機を用いて触媒のメジアン径を１０．５μｍとし、固形
分濃度３６．１重量％である水性スラリーを調製した。
このスラリーの粘度は５８ｃｐｓであった。次いで湿式
粉砕したスラリーに剥離防止剤として、繊維径１０μ
ｍ、平均繊維長さ１８０μｍであるシリカ系セラミック
繊維を触媒重量に対して８．０重量部添加し、撹拌、混
合した。Next, 65 g of this catalyst, 2.0 g of acetic acid, 100 g of pure water and alumina sol (Al 2 O 3 content: 10.
(5% by weight) was stirred and mixed, and an aqueous slurry having a catalyst having a median diameter of 10.5 μm and a solid concentration of 36.1% by weight was prepared using a wet pulverizer.
The viscosity of this slurry was 58 cps. Then, a fiber diameter of 10 μm was added to the wet-milled slurry as an anti-peeling agent.
m, an average fiber length of 180 μm, and 8.0 parts by weight of a silica-based ceramic fiber based on the weight of the catalyst were added, followed by stirring and mixing.
【００４０】この水性スラリーを実施例１に記載と同様
の方法でハニカム構造体セル表面に触媒成分を２回ウォ
ッシュコートしてハニカム構造体触媒を調製した。得ら
れたハニカム構造体触媒は２０５ｇ／Ｌの触媒成分がコ
ートされた。This aqueous slurry was wash-coated twice on the surface of the honeycomb structure cell with the catalyst component in the same manner as described in Example 1 to prepare a honeycomb structure catalyst. The obtained honeycomb structure catalyst was coated with a catalyst component of 205 g / L.
【００４１】また、実施例１と同様に剥離試験を行な
い、その剥離率をコート回数、コート量と共に表１に示
す。A peeling test was conducted in the same manner as in Example 1, and the peeling rate is shown in Table 1 together with the number of coatings and the amount of coating.
【００４２】比較例１ ビーカーに純水２５０ｇを採り、硝酸銀４．１４ｇを添
加して溶解した。４０℃のこの液に粉末アルミナ水和酸
化物（商品名：Ｐｕｒａｌ ＳＢ、Ｃｏｎｄｅａ社製）
１００ｇを加えて撹拌、懸濁し、別に調製した塩化アン
モニウム１．４ｇを純水５０ｇに溶解した水溶液を１５
分間で添加してアルミナ水和酸化物粒子表面に塩化銀を
担持させた。６０分間熟成した後、スプレードライし、
得られた粉末をさらに３９０℃で６０分間焼成すること
により銀に換算して２．９７重量％を含有する銀／アル
ミナ触媒を調製した。 Comparative Example 1 250 g of pure water was placed in a beaker, and 4.14 g of silver nitrate was added and dissolved. Powdered alumina hydrated oxide (trade name: Pural SB, manufactured by Condea) was added to this liquid at 40 ° C.
100 g was added thereto, and the mixture was stirred and suspended. An aqueous solution prepared by dissolving 1.4 g of separately prepared ammonium chloride in 50 g of pure water was added to 15 g of an aqueous solution.
Min. To support silver chloride on the surface of the alumina hydrated oxide particles. After aging for 60 minutes, spray dry,
The obtained powder was further calcined at 390 ° C. for 60 minutes to prepare a silver / alumina catalyst containing 2.97% by weight in terms of silver.
【００４３】次に、この触媒４５ｇと純水１００ｇ、酢
酸２．２５ｇおよびアルミナゾル（Ａｌ2Ｏ3含有率１
０．５重量％）２１．４ｇを加えて撹拌、混合し、さら
に湿式粉砕機を用いて触媒のメジアン径を８．５μｍと
し、固形分濃度２８．０重量％の水性スラリーを調製し
た。このスラリーの粘度を測定したところ１５ｃｐｓで
あった。Next, 45 g of this catalyst, 100 g of pure water, 2.25 g of acetic acid and alumina sol (Al 2 O 3 content 1
0.5% by weight), and the mixture was stirred and mixed. Further, an aqueous slurry having a solid content of 28.0% by weight was prepared using a wet pulverizer to adjust the median diameter of the catalyst to 8.5 μm. The viscosity of this slurry was measured and found to be 15 cps.
【００４４】この水性スラリーを実施例１に記載と同様
の方法でハニカム構造体セル表面に触媒成分を５回ウォ
ッシュコートしてハニカム構造体触媒を調製した。得ら
れたハニカム構造体触媒は１５３ｇ／Ｌの触媒成分がコ
ートされた。This aqueous slurry was wash-coated five times with the catalyst component on the surface of the honeycomb structure cell in the same manner as described in Example 1 to prepare a honeycomb structure catalyst. The obtained honeycomb structure catalyst was coated with a catalyst component of 153 g / L.
【００４５】また、実施例１と同様に剥離試験を行な
い、その剥離率をコート回数、コート量と共に表１に示
す。A peeling test was conducted in the same manner as in Example 1, and the peeling rate is shown in Table 1 together with the number of coatings and the amount of coating.
【００４６】[0046]
【表１】 [Table 1]
【００４７】[0047]
【発明の効果】本発明の製造方法によれば、ウォッシュ
コートに用いる水性スラリーに剥離防止剤としてのシリ
カ系セラミック繊維を加えることにより、少ないコート
回数でより多くの触媒成分をハニカム構造体表面にコー
トすることが可能である。また、塗布された触媒成分の
コート膜が添加されたシリカ系セラミック繊維によって
強固に保持されているため、コート量が著しく多いハニ
カム構造体触媒であっても使用中の触媒成分の剥離が極
めて少なく、触媒の耐久性、製造における経済性、剥離
量が少ないことによる使用時の環境良化等の利点を有す
ることから、本発明により得られるハニカム構造体触媒
は、排ガス浄化用触媒への適用には極めて有利である。According to the production method of the present invention, by adding silica-based ceramic fibers as an anti-peeling agent to the aqueous slurry used for wash coating, more catalyst components can be applied to the surface of the honeycomb structure with a small number of coatings. It is possible to coat. In addition, since the coated film of the applied catalyst component is firmly held by the added silica-based ceramic fiber, even if the honeycomb structure catalyst has a remarkably large coating amount, peeling of the used catalyst component is extremely small. Since the honeycomb structure catalyst obtained by the present invention has advantages such as durability of the catalyst, economical efficiency in production, and improvement in environment during use due to a small amount of peeling, the honeycomb structure catalyst obtained by the present invention is suitable for application to an exhaust gas purification catalyst. Is very advantageous.
フロントページの続き (51)Int.Cl.7 識別記号 ＦＩ Ｂ０１Ｊ 23/58 Ｂ０１Ｄ 53/36 Ｃ 35/04 ３０１ １０２Ｈ (72)発明者 小島 光雄 新潟県新津市滝谷本町１番26号日揮化学 株式会社新津事業所内 (56)参考文献 特開 昭62−129146（ＪＰ，Ａ) 特開 平４−131140（ＪＰ，Ａ) 特開 昭58−30333（ＪＰ，Ａ) 特開 昭54−136587（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) B01J 21/00 - 38/74 B01D 53/86 B01D 53/94 Continued on the front page. (51) Int.Cl. 7 Identification code FI B01J 23/58 B01D 53/36 C 35/04 301 102H (72) Inventor Mitsuo Kojima 1-26 Takiya Honcho, Niitsu City, Niigata Prefecture JGC Corporation Niitsu Office (56) References JP-A-62-129146 (JP, A) JP-A-4-131140 (JP, A) JP-A-58-30333 (JP, A) JP-A-54-136587 (JP, A A) (58) Field surveyed (Int. Cl. 7 , DB name) B01J 21/00-38/74 B01D 53/86 B01D 53/94
Claims (4)
を有するハニカム構造体の表面に、触媒を固着させてな
る排ガス浄化用ハニカム構造体触媒の製造方法であっ
て、該触媒を水性スラリー化してハニカム構造体表面に
コートして固着させるに際し、該触媒とアルミナゾル、
シリカゾル、チタニアゾル、ジルコニアゾルから選択さ
れた少なくとも１種のゾルからなる固着剤と酢酸、無水
酢酸、酢酸のアルカリ塩から選択された少なくとも１種
の粘度低下剤、および該触媒のメジアン径の０．９５〜
１２．５倍の繊維径を有するシリカ系セラミック繊維か
らなる剥離防止剤とを含有するコート用水性スラリーを
該ハニカム構造体表面に塗布し、該触媒をハニカム構造
体表面に固着させ、次いで焼成することを特徴とする排
ガス浄化用ハニカム構造体触媒の製造方法。1. A method for producing a honeycomb structure catalyst for purifying exhaust gas, comprising: attaching a catalyst to a surface of a honeycomb structure having a large number of cells formed in a gas flow direction. The catalyst and the alumina sol,
A fixing agent comprising at least one sol selected from silica sol, titania sol, and zirconia sol, at least one viscosity reducing agent selected from acetic acid, acetic anhydride, and an alkali salt of acetic acid; 95-
An aqueous slurry for coating containing a silica-based ceramic fiber having a fiber diameter of 12.5 times and an anti-peeling agent is applied to the surface of the honeycomb structure, the catalyst is fixed on the surface of the honeycomb structure, and then fired. A method for producing a honeycomb structured catalyst for purifying exhaust gas, comprising the steps of:
された少なくとも１種の活性成分が多孔質耐熱性担体に
担持されたものであり、該活性成分を銀に換算して０．
０１〜２０．０重量％含有する請求項１に記載の排ガス
浄化用ハニカム構造体触媒の製造方法。2. The catalyst according to claim 1, wherein at least one active ingredient selected from silver or a silver compound is supported on a porous heat-resistant carrier.
The method for producing a honeycomb structured catalyst for purifying exhaust gas according to claim 1, which is contained in an amount of from 0.01 to 20.0% by weight.
ー中の触媒量に対して、前記粘度低下剤を０．５〜１
５．０重量％含有する請求項１または２に記載の排ガス
浄化用ハニカム構造体触媒の製造方法。3. The aqueous slurry for coating contains 0.5 to 1 of the viscosity reducing agent based on the amount of catalyst in the slurry.
The method for producing a honeycomb structured catalyst for exhaust gas purification according to claim 1, which contains 5.0% by weight.
メジアン径が０．１〜１５．０μｍであり、かつシリカ
系セラミック繊維の繊維径が６．０〜１５．０μｍであ
ることを特徴とする請求項１、２または３に記載の排ガ
ス浄化用ハニカム構造体触媒の製造方法。4. The catalyst according to claim 1, wherein the median diameter of the catalyst in the aqueous slurry for coating is from 0.1 to 15.0 μm, and the fiber diameter of the silica-based ceramic fibers is from 6.0 to 15.0 μm. The method for producing a honeycomb structured catalyst for exhaust gas purification according to claim 1, 2 or 3.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP06304204A JP3093119B2 (en) | 1994-11-15 | 1994-11-15 | Method for producing honeycomb structured catalyst for exhaust gas purification |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP06304204A JP3093119B2 (en) | 1994-11-15 | 1994-11-15 | Method for producing honeycomb structured catalyst for exhaust gas purification |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH08131849A JPH08131849A (en) | 1996-05-28 |
| JP3093119B2 true JP3093119B2 (en) | 2000-10-03 |
Family
ID=17930275
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP06304204A Expired - Fee Related JP3093119B2 (en) | 1994-11-15 | 1994-11-15 | Method for producing honeycomb structured catalyst for exhaust gas purification |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3093119B2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4246412B2 (en) * | 2001-07-05 | 2009-04-02 | 株式会社日本触媒 | Exhaust gas treatment catalyst and exhaust gas purification method using the same |
| JP6421018B2 (en) * | 2014-11-20 | 2018-11-07 | 花王株式会社 | Method for producing catalyst fiber structure |
| BR112017005591A2 (en) | 2014-11-20 | 2018-04-17 | Kao Corporation | catalyst fibrous structure having a catalyst metal carried on a fibrous structure, and method of production for a fibrous catalyst structure |
| CN111001430B (en) * | 2019-12-17 | 2023-08-15 | 江苏苏净集团有限公司 | Adsorption/catalytic material for waste gas treatment and preparation method thereof |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54136587A (en) * | 1978-04-17 | 1979-10-23 | Toyota Motor Corp | Production of exhaust gas cleaning catalyst |
| JPS5830333A (en) * | 1981-07-24 | 1983-02-22 | Toyota Motor Corp | Coating method for catalyst carrier with high-temperature calcined alumina film |
| JPH0771634B2 (en) * | 1985-11-28 | 1995-08-02 | 株式会社日本触媒 | Exhaust gas purifying catalyst and its manufacturing method |
| JPH04131140A (en) * | 1990-09-21 | 1992-05-01 | N E Chemcat Corp | Manufacture of catalyst for purifying exhaust gas |
-
1994
- 1994-11-15 JP JP06304204A patent/JP3093119B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH08131849A (en) | 1996-05-28 |
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