JP4609831B2 - Honeycomb carrier for exhaust gas purification catalyst and manufacturing method thereof - Google Patents
Honeycomb carrier for exhaust gas purification catalyst and manufacturing method thereof Download PDFInfo
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- JP4609831B2 JP4609831B2 JP2003203271A JP2003203271A JP4609831B2 JP 4609831 B2 JP4609831 B2 JP 4609831B2 JP 2003203271 A JP2003203271 A JP 2003203271A JP 2003203271 A JP2003203271 A JP 2003203271A JP 4609831 B2 JP4609831 B2 JP 4609831B2
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- exhaust gas
- containing compound
- honeycomb carrier
- mass
- magnesium titanate
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- 239000003054 catalyst Substances 0.000 title claims description 46
- 238000000746 purification Methods 0.000 title claims description 12
- 238000004519 manufacturing process Methods 0.000 title claims description 7
- 150000001875 compounds Chemical class 0.000 claims description 54
- 239000000203 mixture Substances 0.000 claims description 49
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 46
- SNAAJJQQZSMGQD-UHFFFAOYSA-N aluminum magnesium Chemical compound [Mg].[Al] SNAAJJQQZSMGQD-UHFFFAOYSA-N 0.000 claims description 46
- 239000011777 magnesium Substances 0.000 claims description 40
- 239000002994 raw material Substances 0.000 claims description 26
- 229910052650 alkali feldspar Inorganic materials 0.000 claims description 18
- 239000000463 material Substances 0.000 claims description 17
- 238000000034 method Methods 0.000 claims description 16
- 229910052749 magnesium Inorganic materials 0.000 claims description 12
- 229910052782 aluminium Inorganic materials 0.000 claims description 10
- 229910052751 metal Inorganic materials 0.000 claims description 10
- 239000002184 metal Substances 0.000 claims description 10
- 229910052719 titanium Inorganic materials 0.000 claims description 10
- 229910000789 Aluminium-silicon alloy Inorganic materials 0.000 claims description 9
- 229910052783 alkali metal Inorganic materials 0.000 claims description 9
- 150000001340 alkali metals Chemical class 0.000 claims description 9
- 238000010304 firing Methods 0.000 claims description 9
- 239000000446 fuel Substances 0.000 claims description 9
- 229910052784 alkaline earth metal Inorganic materials 0.000 claims description 7
- 150000001342 alkaline earth metals Chemical class 0.000 claims description 7
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims description 6
- 238000006243 chemical reaction Methods 0.000 claims description 5
- 239000002245 particle Substances 0.000 claims description 5
- 238000005192 partition Methods 0.000 claims description 3
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 48
- 239000007789 gas Substances 0.000 description 35
- 239000010936 titanium Substances 0.000 description 25
- 230000035939 shock Effects 0.000 description 15
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 14
- 239000013078 crystal Substances 0.000 description 14
- 239000000919 ceramic Substances 0.000 description 11
- 229910052878 cordierite Inorganic materials 0.000 description 11
- 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 11
- CPLXHLVBOLITMK-UHFFFAOYSA-N Magnesium oxide Chemical compound [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 9
- 238000005979 thermal decomposition reaction Methods 0.000 description 9
- 210000004027 cell Anatomy 0.000 description 8
- 230000000052 comparative effect Effects 0.000 description 8
- 238000005245 sintering Methods 0.000 description 8
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical group O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 7
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 6
- 229910052700 potassium Inorganic materials 0.000 description 6
- 239000011591 potassium Substances 0.000 description 6
- 229910000505 Al2TiO5 Inorganic materials 0.000 description 5
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 5
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 5
- 239000011230 binding agent Substances 0.000 description 5
- 239000000395 magnesium oxide Substances 0.000 description 5
- 235000012245 magnesium oxide Nutrition 0.000 description 5
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 4
- 239000003513 alkali Substances 0.000 description 4
- 239000002518 antifoaming agent Substances 0.000 description 4
- 229910002091 carbon monoxide Inorganic materials 0.000 description 4
- 230000007797 corrosion Effects 0.000 description 4
- 238000005260 corrosion Methods 0.000 description 4
- 238000001125 extrusion Methods 0.000 description 4
- 229930195733 hydrocarbon Natural products 0.000 description 4
- 150000002430 hydrocarbons Chemical class 0.000 description 4
- 238000000465 moulding Methods 0.000 description 4
- FGIUAXJPYTZDNR-UHFFFAOYSA-N potassium nitrate Chemical compound [K+].[O-][N+]([O-])=O FGIUAXJPYTZDNR-UHFFFAOYSA-N 0.000 description 4
- AABBHSMFGKYLKE-SNAWJCMRSA-N propan-2-yl (e)-but-2-enoate Chemical compound C\C=C\C(=O)OC(C)C AABBHSMFGKYLKE-SNAWJCMRSA-N 0.000 description 4
- 239000006104 solid solution Substances 0.000 description 4
- 229910052596 spinel Inorganic materials 0.000 description 4
- 239000011029 spinel Substances 0.000 description 4
- 239000002344 surface layer Substances 0.000 description 4
- ZMANZCXQSJIPKH-UHFFFAOYSA-N Triethylamine Chemical compound CCN(CC)CC ZMANZCXQSJIPKH-UHFFFAOYSA-N 0.000 description 3
- 238000002441 X-ray diffraction Methods 0.000 description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 150000002500 ions Chemical class 0.000 description 3
- 238000002156 mixing Methods 0.000 description 3
- 239000001301 oxygen Substances 0.000 description 3
- 229910052760 oxygen Inorganic materials 0.000 description 3
- 239000011148 porous material Substances 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- 239000000377 silicon dioxide Substances 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- KBPLFHHGFOOTCA-UHFFFAOYSA-N 1-Octanol Chemical compound CCCCCCCCO KBPLFHHGFOOTCA-UHFFFAOYSA-N 0.000 description 2
- 229910020068 MgAl Inorganic materials 0.000 description 2
- 239000004372 Polyvinyl alcohol Substances 0.000 description 2
- 229910052581 Si3N4 Inorganic materials 0.000 description 2
- 229910010413 TiO 2 Inorganic materials 0.000 description 2
- JFBZPFYRPYOZCQ-UHFFFAOYSA-N [Li].[Al] Chemical compound [Li].[Al] JFBZPFYRPYOZCQ-UHFFFAOYSA-N 0.000 description 2
- 150000001768 cations Chemical class 0.000 description 2
- 238000002485 combustion reaction Methods 0.000 description 2
- HPNMFZURTQLUMO-UHFFFAOYSA-N diethylamine Chemical compound CCNCC HPNMFZURTQLUMO-UHFFFAOYSA-N 0.000 description 2
- 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 2
- 239000000839 emulsion Substances 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 230000003628 erosive effect Effects 0.000 description 2
- 230000020169 heat generation Effects 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 239000006082 mold release agent Substances 0.000 description 2
- 229910052863 mullite Inorganic materials 0.000 description 2
- 229920002451 polyvinyl alcohol Polymers 0.000 description 2
- 235000010333 potassium nitrate Nutrition 0.000 description 2
- 239000004323 potassium nitrate Substances 0.000 description 2
- 238000010298 pulverizing process Methods 0.000 description 2
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 2
- 229910010271 silicon carbide Inorganic materials 0.000 description 2
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 2
- 230000008646 thermal stress Effects 0.000 description 2
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 2
- GLDUZMNCEGHSBP-UHFFFAOYSA-N 2-(2-octylphenoxy)ethanol Chemical compound CCCCCCCCC1=CC=CC=C1OCCO GLDUZMNCEGHSBP-UHFFFAOYSA-N 0.000 description 1
- 229920002134 Carboxymethyl cellulose Polymers 0.000 description 1
- 238000005481 NMR spectroscopy Methods 0.000 description 1
- 229920002472 Starch Polymers 0.000 description 1
- 235000021355 Stearic acid Nutrition 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 229910052788 barium Inorganic materials 0.000 description 1
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 1
- 239000001768 carboxy methyl cellulose Substances 0.000 description 1
- 235000010948 carboxy methyl cellulose Nutrition 0.000 description 1
- 239000008112 carboxymethyl-cellulose Substances 0.000 description 1
- 239000000969 carrier Substances 0.000 description 1
- 239000012876 carrier material Substances 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 239000000571 coke Substances 0.000 description 1
- 238000009841 combustion method Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000010433 feldspar Substances 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 210000002287 horizontal cell Anatomy 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 238000011068 loading method Methods 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- HZZOEADXZLYIHG-UHFFFAOYSA-N magnesiomagnesium Chemical compound [Mg][Mg] HZZOEADXZLYIHG-UHFFFAOYSA-N 0.000 description 1
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 229920000609 methyl cellulose Polymers 0.000 description 1
- 239000001923 methylcellulose Substances 0.000 description 1
- 239000004200 microcrystalline wax Substances 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 235000010755 mineral Nutrition 0.000 description 1
- 150000002823 nitrates Chemical class 0.000 description 1
- QIQXTHQIDYTFRH-UHFFFAOYSA-N octadecanoic acid Chemical compound CCCCCCCCCCCCCCCCCC(O)=O QIQXTHQIDYTFRH-UHFFFAOYSA-N 0.000 description 1
- OQCDKBAXFALNLD-UHFFFAOYSA-N octadecanoic acid Natural products CCCCCCCC(C)CCCCCCCCC(O)=O OQCDKBAXFALNLD-UHFFFAOYSA-N 0.000 description 1
- 239000005416 organic matter Substances 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 229920013716 polyethylene resin Polymers 0.000 description 1
- 229920001451 polypropylene glycol Polymers 0.000 description 1
- -1 potassium Chemical compound 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 238000000197 pyrolysis Methods 0.000 description 1
- 239000011163 secondary particle Substances 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 239000008107 starch Substances 0.000 description 1
- 235000019698 starch Nutrition 0.000 description 1
- 239000008117 stearic acid Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 230000035882 stress Effects 0.000 description 1
- 229910052815 sulfur oxide Inorganic materials 0.000 description 1
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 230000036962 time dependent Effects 0.000 description 1
- LLZRNZOLAXHGLL-UHFFFAOYSA-J titanic acid Chemical compound O[Ti](O)(O)O LLZRNZOLAXHGLL-UHFFFAOYSA-J 0.000 description 1
Images
Classifications
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
- Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
Description
【０００１】
【発明の属する技術分野】
本発明は、各種の排ガス、特に、排ガス中にＮＯｘが含まれる、自動車用の排ガスを浄化する触媒を担持するための担体及びその製造方法に関する。
【０００２】
【従来の技術】
各種の燃焼排ガスの浄化装置のなかで、特に現在広く使用されている自動車排ガス浄化装置に使用される触媒を担持するためのハニカム担体に要求される主な特性は、所謂、耐熱性や耐熱衝撃性である。これは、排ガス中の未燃焼炭化水素や一酸化炭素の触媒酸化反応により急激な発熱が生じるために、８５０℃以上の高温度になるため、高い耐熱性が必要である。また、耐熱衝撃性は、このような急激な発熱による温度上昇のために、ハニカム内に引き起こされる熱応力により亀裂や破壊に耐える性質である。耐熱衝撃性は、熱膨張係数が小さいほどその耐久温度差が大きい。
【０００３】
このような耐熱性や耐熱衝撃性の要求のために、従来、ハニカム担体の材質としては、各種のセラミクスが提案されているものの、もっぱらコージェライト材料が使用されている。コージェライト材料が使用される主な理由は、コージェライトが１４００℃という高い耐熱性を有するとともに、セラミクスのなかでも熱膨張係数が極めて小さく、耐熱衝撃性が大きいことにある。
【０００４】
しかしながら、ハニカム担体の材質としてコージェライト材料は、耐熱性や耐熱衝撃性についてはかなり優れた性質を有するが、一方で、環境上の問題からその除去が急務とされる窒素酸化物（ＮＯx）を含有する排ガスの浄化する触媒担体として使用される場合に重要な難点を有する。すなわち、排ガス中のＮＯｘの除去触媒として、通常、アルカリ金属やアルカリ土類金属成分を含む触媒が使用されるが、この場合、アルカリ金属やアルカリ土類金属の一部が、高温度下においては、担体であるコージェライト内に浸透し、コージェライトと反応する結果、コージェライトの劣化を招くとともに、触媒の損失をもたらすために排ガス中のＮＯｘの除去の低下を引き起こす。これを防ぐために、触媒表面をシリカ（ＳｉＯ2）で被覆する方法などが提案されているが、余分の工程を必要とし、コストの上昇を余儀なくする。
【０００５】
一方、燃費の向上や環境上の問題から、近年自動車の主流の燃焼方式になってきている、燃料をエンジン内に直接噴射する方式や燃料を稀薄燃焼させる方式では、排ガス中のＮＯｘの除去は、炭化水素や一酸化炭素よりも特に重要な問題になっている。このため、排ガスの浄化触媒を担持するハニカム担体は、その材質としてコージェライトに代わる材料が切望されている。
【０００６】
コージェライト以外の材質として、特許文献１には、炭化ケイ素、窒化ケイ素、ムライト、アルミウムチタネート（チタン酸アルミニウム）、リチウムアルミウムシリケートなどのセラミクスが羅列されているが、これらはいずれも上記ハニカム担体の材料としては不充分である。すなわち、炭化ケイ素、ムライトなどは熱膨張係数が大きく耐熱衝撃性が劣る。また、窒化ケイ素、リチウムアルミニウムシリケートなどは耐熱性の点で性能として不充分である。
【０００７】
また、アルミニウムチタネートは、１７００℃を越える高温下でも優れた安定性、極めて小さい熱膨張係数、及び優れた耐熱衝撃性を有する。しかし、一方においては、結晶構造の異方性が大きいために結晶粒界に熱応力によるズレが生じ易いため機械的強度が小さいという欠点がある結果、壁厚の薄いセル密度の大きいハニカムの製造は困難であり、また自動車などに搭載され、高温下で機械的振動の負荷がかかる排ガスフィルタとしての使用は困難である。さらに、これらのアルミウムチタネートなどは、通常８００〜１２８０℃の温度範囲に分解領域を有し、このような温度範囲を含む領域で長時間継続使用できないという問題点を有す。
【特許文献１】
ＷＯ０１／０３７９７１号公報
【０００８】
【発明が解決しようとする課題】
本発明は、特に、排ガス中にＮＯｘが含まれる、自動車用の排ガスを浄化する触媒を担持するための担体であって、耐熱性、耐熱衝撃性、機械的強度、及び熱分解耐性に優れ、かつアルカリ成分を含有する触媒に対する耐侵食性が高く、長期の使用でも劣化することのない耐久性に優れたハニカム担体、及びその製造方法を提供する。
【０００９】
【課題を解決する手段】
本発明は、上記課題を解決するために、チタン酸アルミニウムマグネシウムに着目し鋭意検討したところ次の新規な知見を得た。すなわち、Ｍｇ含有化合物、Ａｌ含有化合物及びＴｉ含有化合物を含む混合物に対して、特定のアルカリ長石を添加した混合物を焼成して得られる焼結体を使用したハニカム担体は、高い耐熱性と低熱膨張性に基づく耐熱衝撃性を維持しながら、従来のチタン酸アルミニウムマグネシウム焼結体と異なり、大きい機械的強度、熱分解耐性を有するとともに、この焼結体は、ＮＯｘを除去する触媒として、アルカリ金属やアルカリ土類金属成分を含む触媒が使用する場合も従来のコージェライト材料のように劣化することがなく、長期にわたり安定して使用できるという知見が得られた。
【００１０】
かかる本発明は、上記新規な知見に基づいて完成されたものであり、次の要旨を有するものである。
（１）排ガスを浄化させる触媒を担持するためのハニカム担体であって、該ハニカム担体の材質が、組成式：ＭｇxＡｌ2(1-x)Ｔｉ(1+x)Ｏ5（式中、式中、０<ｘ<１）で表わされるチタン酸アルミニウムマグネシウムにおけるＭｇ，Ａｌ及びＴｉの金属成分比と同様の金属成分比率で含む、Ｍｇ含有化合物、Ａｌ含有化合物及びＴｉ含有化合物を含む混合物を酸化物換算量として１００質量部と、並びに組成式：（ＮａyＫ1-y）ＡｌＳｉ3Ｏ8（式中、０≦ｙ≦１）で表わされるアルカリ長石１〜１０質量部とを含有する原料混合物を１０００〜１７００℃で焼成したチタン酸アルミニウムマグネシウム焼結体であることを特徴とする排ガス浄化触媒用ハニカム担体。
（２）ハニカム構造触媒担体が、壁厚０．０５〜０．６ｍｍ、セル密度１５〜１２４セル／ｃｍ2を有し、かつ隔壁の気孔率が２０〜５０％、熱膨張係数が３．０×１０-6Ｋ-1以下である上記（１）に記載のハニカム担体。
（３）前記触媒が、排ガス中のＮＯｘを除去するためのアルカリ金属又はアルカリ土類金属成分を含む、上記（１）又は（２）に記載の触媒担体。
（４）排ガスが、燃料をエンジン内に直接噴射する方式又は燃料を稀薄燃焼させる方式の自動車の排ガスである、上記（１）、（２）又は（３）に記載のハニカム担体。
（５）組成式：ＭｇxＡｌ2(1-x)Ｔｉ(1+x)Ｏ5（式中、式中、０<ｘ<１）で表わされるチタン酸アルミニウムマグネシウムにおけるＭｇ，Ａｌ及びＴｉの金属成分比と同様の金属成分比率で含む、Ｍｇ含有化合物、Ａｌ含有化合物及びＴｉ含有化合物を含む混合物を酸化物換算量として１００質量部、並びに組成式：（ＮａyＫ1-y）ＡｌＳｉ3Ｏ8（式中、０≦ｙ≦１）で表わされるアルカリ長石を１〜１０質量部含有する原料混合物を調製し、該原料混合物に成形助剤を加えて混練して押出成形可能に可塑化し、ハニカム体に押出成形後、１０００〜１７００℃にて焼成することを特徴とする排ガス浄化触媒用ハニカム担体の製造方法。
（６）前記原料混合物に含まれる各成分の平均粒子径が１０μｍ以下である上記（５）に記載の製造方法。
（７）排ガスを浄化させる触媒を担持したハニカム担体に排ガスを接触させる排ガスの浄化方法であって、該ハニカム担体の材質が、組成式：ＭｇxＡｌ2(1-x)Ｔｉ(1+x)Ｏ5（式中、式中、０<ｘ<１）で表わされるチタン酸アルミニウムマグネシウムにおけるＭｇ，Ａｌ及びＴｉの金属成分比と同様の金属成分比率で含む、Ｍｇ含有化合物、Ａｌ含有化合物及びＴｉ含有化合物を含む混合物を酸化物換算量として１００質量部と、組成式：（ＮａyＫ1-y）ＡｌＳｉ3Ｏ8（式中、０≦ｙ≦１）で表わされるアルカリ長石１〜１０質量部とを含有する混合物を１０００〜１７００℃で焼成したチタン酸アルミニウムマグネシウム焼結体であることを特徴とする排ガスの浄化方法。
【００１１】
本発明によるハニカム担体が、何故に、上記のように高い耐熱性と耐熱衝撃性を維持しながら、従来のチタン酸アルミニウムマグネシウム焼結体とは異なり、優れた機械的強度と熱分解耐性を有し、更には、ＮＯxを含有する排ガスの浄化するアルカリ金属成分を含む触媒担体として使用される場合にも劣化しないかについては、必ずしも明確でないが、ほぼ下記の理由によるものと推測される。
【００１２】
すなわち、本発明のハニカム担体の基本構造となるチタン酸アルミニウムマグネシウムの結晶は、その生成過程においてアルカリ長石が存在することにより、アルカリ長石が液相となる状態で成長されるために緻密な結晶が形成され機械的強度が向上する。また、アルカリ長石に含まれるＳｉ成分は、焼成によってチタン酸アルミニウムマグネシウムを形成する際にチタン酸アルミニウムマグネシウムの結晶格子に固溶するが、その際のＳｉの固溶形態には６配位で存在して結晶粒内部で固溶するものと、４配位で存在して結晶粒表層部で固溶するものの２種類が考えられる。これは NMR (核磁気共鳴) 測定によってチタン酸アルミニウムマグネシウム結晶中のＳｉが６配位と４配位の２種類の状態で存在していることが観測された結果によっても裏付けられる。
【００１３】
すなわち、チタン酸アルミニウムマグネシウム結晶粒の内部に固溶するＳｉは６配位で存在して４価であって、同じく６配位で２価のＭｇとペアとなって、両者でトータル６価となり、隣接する２つの６配位で３価のＡｌ（トータル６価）を置換する。この理由としては、電荷のバランスが保たれるためであることはもとより、イオン半径の相関からも説明できる。つまりＳｉ4+とＭｇ2+のイオン半径はそれぞれ０．５４Åと０．８６Å、であり、両者の平均イオン半径は０．７０Åとなることから、Ａｌ3+のイオン半径の０．６８Åと近似したものとなり、Ｓｉ4+とＭｇ2+のペアによる２つのＡｌ3+の占有はエネルギー的にも無理のない固溶状態になるためである。このように、ＳｉとＭｇの同時存在によって、チタン酸アルミニウムマグネシウムは高温下でも各カチオン間のイオンの拡散を抑制でき、安定な結晶構造をとるため、優れた熱分解耐性を発現するものと考えられる。
【００１４】
一方、チタン酸アルミニウムマグネシウム結晶粒の表層部に固溶するＳｉは６配位としてではなく４配位で存在する。これは表層部のＳｉは酸素を共有する、いわゆる相手となるカチオンが少ないために、酸素の結合状態がより安定な４配位をとるためと考えられる。このように結晶粒の表層部に固溶するＳｉはチタン酸アルミニウムマグネシウムの結晶を擬似的にコーティングする状態となり、本発明のハニカム担体がアルカリ金属を含む触媒担体として使用される場合にも、高温下におけるアルカリ成分による担体への侵食に対して優れた耐食性を有することとなり、長時間使用しても劣化しない特性をもたらすと考えられる。
【００１５】
【発明の実施の形態】
本発明では、上記ハニカム構造触媒担体の材質として、組成式：ＭｇxＡｌ2(1-x)Ｔｉ(1+x)Ｏ5（式中、式中、０<ｘ<１）で表わされるチタン酸アルミニウムマグネシウムにおけるＭｇ，Ａｌ及びＴｉの金属成分比と同様の金属成分比率で含む、Ｍｇ含有化合物、Ａｌ含有化合物及びＴｉ含有化合物を含む混合物を酸化物換算量として１００質量部、並びに組成式：（ＮａyＫ1-y）ＡｌＳｉ3Ｏ8（式中、０≦ｙ≦１）で表わされるアルカリ長石を１〜１０質量部含有する原料混合物を１０００〜１７００℃で焼成したチタン酸アルミニウムマグネシウム焼結体が使用される。
【００１６】
原料として用いる上記Ｍｇ含有化合物、Ａｌ含有化合物、及びＴｉ含有化合物としては、焼成によりチタン酸アルミニウムマグネシウムを合成できる成分であれば特に限定なく使用できる。Ｍｇ含有化合物、Ａｌ含有化合物、及びＴｉ含有化合物としては、それぞれ別の化合物でなくてもよく、２種以上の金属成分を含む化合物であってもよい。これらの原料化合物は、通常、アルミナセラミクス、チタニアセラミクス、マグネシアセラミクス、チタン酸アルミウムセラミクス、チタン酸マグネシウムセラミクス、スピネルセラミクス、チタン酸アルミニウムマグネシウムセラミクスなどの各種セラミクスの原料として用いられるもののうちから適宜選択して用いればよい。このような化合物の具体例としては、Ａｌ2Ｏ3、ＴｉＯ2、ＭｇＯなどの酸化物、ＭｇＡｌ2Ｏ4、Ａｌ2ＴｉＯ5、ＭｇＴｉＯ5、ＭｇとＴｉを含む各スピネル型構造体などの２種類以上の金属成分を含む複合酸化物、Ａｌ、Ｔｉ及びＭｇからなる群から選ばれた１種又は２種以上の金属成分を含む化合物（炭酸塩、硝酸塩、硫酸塩など）などを例示できる。
【００１７】
Ｍｇ含有化合物、Ａｌ含有化合物、及びＴｉ含有化合物の混合割合はこれらの化合物に含まれる金属成分の比率が、上記した組成式：ＭｇxＡｌ2(1-x)Ｔｉ(1+x)Ｏ5（式中、式中、０<ｘ<１）で表わされるチタン酸アルミニウムマグネシウムにおけるＭｇ，Ａｌ及びＴｉの金属成分比と同様の比率、好ましくは同一の比率となるようにすればよい。このような割合で上記各化合物を混合して用いることによって、原料として用いた混合物における金属成分比と同様の金属成分比を有するチタン酸アルミニウムマグネシウムを得ることができる。
【００１８】
本発明のハニカム担体を得る場合、上記したＭｇ含有化合物、Ａｌ含有化合物及びＴｉ含有化合物を含む混合物に対して、添加剤としてアルカリ長石を加えることが必要である。アルカリ長石は、チタン酸アルミニウムマグネシウムの焼結助剤であるとともに、チタン酸アルミニウムマグネシウムにＳｉ成分を添加する役割を兼ねるものであり、組成式：（ＮａyＫ1-y）ＡｌＳｉ3Ｏ8で表わされる。式中、ｙは、０≦ｙ≦１を満足し、０．１≦ｙ≦１が好ましく、特に、０．１５≦ｙ≦０．８５であるものが好ましい。この範囲のｙ値を有するアルカリ長石は融点が低く、チタン酸アルミニウムマグネシウムの焼結促進に特に有効である。
【００１９】
アルカリ長石の使用量は、原料として用いる、Ｍｇ含有化合物、Ａｌ含有化合物及びＴｉ含有化合物の各化合物を酸化物に換算した合計値１００質量部に対して１〜１０質量部程度とすればよく、好ましくは３〜５質量部程度とするのが好適である。この場合の原料混合物を酸化物に換算した合計量とは、原料混合物中に含まれる水分や有機物を除去するための加熱処理を行った後、また、仮焼結を行った場合には、仮焼結後の本焼成前の質量とする。
【００２０】
Ｍｇ含有化合物、Ａｌ含有化合物及びＴｉ含有化合物を含む混合物にアルカリ長石を加えた原料混合物は、必要に応じて他の焼結助剤を加えて得られる焼結体の性質を改善できる。他の焼結助剤としては、例えば、Ｍｇを含むスピネル型構造の酸化物、ＭｇＣＯ3、ＭｇＯなどが挙げられる。
【００２１】
上記の原料混合物は、充分に混合し、粉砕される。原料混合物の混合、粉砕については、特に限定的でなく既知の方法に従って行われる。例えば、ボールミル、媒体攪拌ミルなどを用いて行えばよい。原料混合物の粉砕の程度は、特に限定的でないが、平均粒子径が好ましくは１０μｍ以下、特に好ましくは１〜５μｍが好適である。原料混合物は、二次粒子が形成されない範囲であればできるだけ小さい方が好適である。
【００２２】
原料混合物には、好ましくは、成形助剤を配合することができる。成形助剤としては、結合剤、造孔剤、離型剤、消泡剤、及び解こう剤などの既知のものが使用できる。結合剤としては、ポリビニルアルコール、マイクロワックスエマルジョン、メチルセルロース、カルボキシメチルセルロースなどが好ましい。造孔剤としては、活性炭、コークス、ポリエチレン樹脂、でんぷん、黒鉛などが好ましい。離型剤としては、ステアリン酸エマルジョンなどが、消泡剤としては、ｎ−オクチルアルコール、オクチルフェノキシエタノールなどが、解こう剤としては、ジエチルアミン、トリエチルアミンなどが好ましい。
【００２３】
成形助剤の使用量については特に限定的ではないが、本発明の場合には、原料として用いるＭｇ含有化合物、Ａｌ含有化合物及びＴｉ含有化合物の各化合物を酸化物に換算した合計量１００質量部に対して、いずれも固形物換算でそれぞれ以下の範囲とするのが好適である。すなわち、結合剤を好ましくは０．２〜０．６質量部程度、造孔剤を好ましくは２０〜５０質量部程度、離型剤を好ましくは０．２〜０．７質量部程度、消泡剤を好ましくは０．５〜１．５質量部程度、及び解こう剤を好ましくは０．５〜１．５質量部程度用いるのが好適である。
【００２４】
上記成形助剤を加えた原料混合物は混合、混練して押出し成形可能に可塑化したものを押出成形によりハニカム体に成形する。押出成形の方法については既知の方法が使用でき、ハニカムのセルの断面形状は、円形、楕円形、四角形、三角形のいずれでもよい。また、ハニカム体の全体の形態は円筒体、角筒体のいずれでもよい。成形されたハニカムは、好ましくは乾燥し、次いで１０００〜１７００℃、好ましくは１２５０〜１４５０℃にて焼成される。焼成雰囲気については特に限定がなく、通常採用されている空気中などの含酸素雰囲気が好ましい。焼成時間は、焼結が充分に進行するまで焼成すればよく、通常は１〜２０時間程度が採用される。
【００２５】
上記焼成の際の昇温速度や降温速度についても特に制限はなく、得られる焼結体にクラックなどが入らないような条件を適宜設定すればよい。例えば、原料混合物中に含まれる水分、結合剤などの成形助剤を充分に除去するために急激に昇温することなく、徐々に昇温することが好ましい。また、上記した焼成温度に加熱する前に、必要に応じて、好ましくは５００〜１０００℃程度の温度範囲において、１０〜３０時間程度の穏やかな昇温により仮焼結を行うことによって、チタン酸アルミニウムマグネシウムが形成する際におけるクラック発生の原因となる焼結体内の応力を緩和することができ、焼結体中のクラックの発生を抑制して緻密でかつ均一な焼結体を得ることができる。
【００２６】
このようにして得られる焼結体は、組成式：ＭｇxＡｌ2(1-x)Ｔｉ(1+x)Ｏ5（式中、０<ｘ<１）で表わされるチタン酸アルミニウムマグネシウムを基本成分として、アルカリ長石に含まれるＳｉ成分がチタン酸アルミニウムマグネシウムの結晶格子中に固溶したものとなる。このような焼結体は、上記したように、高い耐熱性と耐熱衝撃性を有し、かつ結晶構造が安定化されていることにより、優れた機械的強度及び熱分解耐性を有する焼結体となる。
【００２７】
その結果、この焼結体からなるハニカム体は、壁厚が例えば０．０５〜０．６ｍｍ、セル密度が例えば１５〜１２４セル／ｃｍ2の薄壁ハニカム構造を有する。そして、隔壁の気孔率は例えば２０〜５０％、熱膨張係数は例えば３．０×１０-6Ｋ-1以下である。このハニカム体は、室温から１６００℃程度の高温下においてもチタン酸アルミニウムマグネシウムの熱分解反応が抑制されて安定的に使用できる。
【００２８】
上記ハニカム体は、炭化水素、一酸化炭素，ＮＯｘ，ＳＯｘなどの有害成分を含む各種の排ガス、特に、排ガス中にＮＯｘが含まれる、自動車用の排ガスを浄化するための触媒の担体として使用される。特に、本発明のハニカム担体は、高温度においてアルカリに対して安定性を有するので、排ガス中にＮＯｘが比較的高濃度で含まれる、燃料をエンジン内に直接噴射する方式又は燃料を稀薄燃焼させる方式の自動車の排ガスに対して有効である。
【００２９】
担体に対して担持させる触媒の種類としては、従来の炭化水素や一酸化炭素を除去する所謂三元触媒など既知の種々のものが使用できるが、本発明では、排ガス中のＮＯｘを除去するためのアルカリ金属又はアルカリ土類金属成分を含む触媒に対して特に有効である。アルカリ金属又はアルカリ土類金属のなかでも、ＮＯｘ除去に効果的であるカリウムやバリウム、特にカリウムを含む触媒に対して本発明の担体は有効である。
【００３０】
本発明のハニカム体に上記触媒を担持させる方法は既知の手段が採用される。触媒を担持させる場合、担持率を改善するために必要に応じて、比表面積の大きい材料、例えばアルミナやシリカを介在させることもできる。すなわち、ハニカム担体にアルミナやシリカを担持させ、該担持させたアルミナやシリカに触媒を担持することができる。触媒を担持したハニカム体は、適宜の保持材を使用して好ましくは缶体内に装備されて使用される。
【００３１】
【実施例】
以下、本発明を実施例により具体的に説明するが、本発明はこれらに限定して解釈されるべきではないことはもちろんである。
【００３２】
実施例１
易焼結性α型アルミナを２６．７質量％（２０モル％）、アナターゼ型酸化チタンを６２．８質量％（６０モル％）、及び天然鉱物として存在するペリクレース（periclase）型の酸化マグネシウムを１０．５質量％（２０モル％）からなる混合物１００質量部に対して、（Ｎａ0.6Ｋ0.4）ＡｌＳｉ3Ｏ8 で表されるアルカリ長石を４質量部、バインダーとしてポリビニルアルコールを０．２５質量部、解こう剤としてジエチルアミンを１質量部、消泡剤としてポリプロピレングリコール０．５質量部、及び造孔剤として、粒子径３０μｍ以下の活性炭３５質量部を加えてボールミルで３時間混合後、１２０℃の乾燥機で１２時間以上乾燥させて原料粉末を得た。
【００３３】
得られた原料粉末を平均粒径５μｍ程度に粉砕し、真空押出し成形機（宮崎鉄工社製）を使用して押出し成形し、壁厚 ０．１ｍｍ、セル密度９３セル／ｃｍ2の断面四角セル形状を有する直径：１２９ｍｍ、長さ：１５０ｍｍの円筒形のハニカム体を得た。このハニカム体を乾燥した後、１４００℃にて４時間大気中で焼成した。その後、放冷することにより焼結体を得た。
【００３４】
比較例１
アルカリ長石を使用しないほかは実施例１と全く同様にしてチタン酸アルミニウムマグネシウム焼結体からなるハニカム形状の焼結体を得た。
【００３５】
比較例２
ハニカムフィルタの材料として、コージェライト粉末（２ＭｇＯ・２Ａｌ2O3.・５ＳｉＯ2）を使用し、これから既存の方法で実施することにより実施例１と同形状のハニカムを作製した。
【００３６】
［ハニカム焼結体についての特性試験］
上記の実施例１、及び比較例１、２のハニカム焼結体について、気孔率（％）、室温から８００℃における熱膨張係数（×１０-6Ｋ-1）、水中投下法による耐熱衝撃抵抗（℃）、軟化温度（℃）、及び圧縮強度（ＭＰａ）を測定し、その結果を表１に示した。なお、気孔率は、ＪＩＳＲ１６３４、熱膨張係数は、ＪＩＳＲ１６１８、耐熱衝撃抵抗は、ＪＩＳＲ１６４８、軟化温度は、ＪＩＳＲ２２０９、圧縮強度は、ＪＩＳＲ１６０８に準拠する方法で測定した。なお、圧縮強度については、各ハニカム焼結体から、筒断面の縦、横のセル数がいずれも５セルで長さ方向が１５ｍｍの角筒状の検体を切り出し、これを（Ａ）長さ軸方向（axial）、（Ｂ）垂直方向（tangential）、（Ｃ）長さ軸に４５度の斜めの方向（diagonal）の３方向から測定した。
【００３７】
【表１】
［熱分解耐性試験］
実施例１のハニカムフィルタからいずれも縦１０ｍｍ×横１０ｍｍ×長さ１０ｍｍの試験片を切り出し、１１００℃の高温雰囲気に保持し、チタン酸アルミニウムマグネシウムの残存率α（％）の経時変化を調べることにより熱分解耐性試験を行った。
【００３９】
なお、チタン酸アルミニウムマグネシウムの残存率は、Ｘ線回折測定（ＸＲＤ）のスペクトルから以下の方法により求めた。
まず、チタン酸アルミニウムマグネシウムが熱分解するときにＭｇＡｌ2Ｏ4（スピネル）とＴｉＯ2（ルチル）を生じるので、ルチルの（１１０）面の回折ピークの積分強度（ＩTiO2(110)）とチタン酸アルミニウムマグネシウムの（０２３）面の回折ピークの積分強度（ＩMAT(023)）を用いてチタン酸アルミニウムマグネシウムのルチルに対する強度比Ｒを下記式より求めた。
Ｒ＝ＩMAT(023)／（ＩMAT(023) ＋ＩTiO2(110)）
更に、１１００℃における熱処理を行う前の焼結体についても同様の方法でチタン酸アルミニウムマグネシウムのルチルに対する強度比Ｒ0を求めた。次いで、上記方法で求めたＲとＲ0を用いて、下記式よりチタン酸アルミニウムマグネシウムの残存率α（％）を求めた。
α＝（Ｒ／Ｒ0）×１００
【００４０】
実施例１と比較例１の各焼結体についてのチタン酸アルミニウムマグネシウムの残存率αの経時変化を図１にグラフとして示す。図１から明らかなように、実施例１の焼結体は、比較例１の焼結体に比べてチタン酸アルミニウムマグネシウムの残存率αが長時間に渡って高く維持され、熱分解耐性に優れることがわかる。
【００４１】
［ハニカム体の耐アルカリ性試験］
自動車用排ガスのＮＯｘの除去触媒であるカリウム含有触媒に対するハニカム体の耐食性を調べるために以下の試験を行った。なお、自動車用排ガスのハニカム担体の使用温度は、室温から８５０℃の範囲であり、また、カリウム含有触媒のカリウム濃度はそれほど高い濃度ではないが、本試験では、濃度１モル／リットルの硝酸カリウム水溶液に漬浸、乾燥した試験片を、温度９００℃に保持された炉に長時間保持するという、厳しい条件での加速試験を行った。
【００４２】
［試験方法］
実施例１と比較例２のそれぞれのハニカム体から断面が３０ｍｍ角で長さ５０ｍｍの試験片を切り出し、この試験片を濃度１モル／リットルの硝酸カリウム水溶液中に室温で１０〜６０分間浸漬した。次いで、該試験片を７０℃にて１時間乾燥させた。乾燥させたハニカム体を内径５ｃｍ、長さ４２ｃｍの管状炉に挿入し、該管状炉中に１０％の水分を含む空気を２５ｃｃ／分にて流入させながら、下記の条件にて所定の時間保持した。その後に管状炉から取り出したハニカム体についてＸＲＤ測定を行い、ハニカム体材料の変質について調べた。なお、管状炉中に流入させる１０％の水分を含む空気は、６０℃に制御された水槽に空気を通過させることにより調製した。試験の結果を表２に示す。
保持条件
炉内温度：９００℃、 炉の昇温、降温速度：１００℃／時間
保持時間 ：５０時間、１００時間、１５０時間、２００時間
【００４３】
【表２】
【００４４】
【発明の効果】
本発明のチタン酸アルミニウムマグネシウム焼結体からなるハニカム担体は、高い耐熱性と低熱膨張性に基づく耐熱衝撃性を維持しながら、従来のチタン酸アルミニウムマグネシウム焼結体とは異なり、大きい機械的強度、及び耐熱分解性を有し、さらに触媒に対する耐食性に優れる。この結果、固定体及び移動体のいずれの燃焼源からの排ガス、特に、排ガス中にＮＯｘが含まれる、自動車用の排ガスを浄化する触媒を担持するための担体として有効である。
【図面の簡単な説明】
【図１】本発明の実施例１と比較例１の各焼結体についてのチタン酸アルミニウムマグネシウムの残存率αの経時変化を示す。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a carrier for supporting a catalyst for purifying various exhaust gases, particularly NOx contained in the exhaust gas, and for purifying exhaust gases for automobiles, and a method for producing the same.
[0002]
[Prior art]
Among various types of purification equipment for combustion exhaust gas, the main characteristics required for the honeycomb carrier for supporting the catalyst used in the automobile exhaust gas purification equipment currently widely used are so-called heat resistance and thermal shock. It is sex. This is because a rapid heat generation occurs due to the catalytic oxidation reaction of unburned hydrocarbons and carbon monoxide in the exhaust gas, and the temperature becomes high at 850 ° C. or higher, so high heat resistance is required. Further, the thermal shock resistance is a property that withstands cracks and breakage due to thermal stress caused in the honeycomb due to a temperature rise due to such rapid heat generation. As for thermal shock resistance, the smaller the thermal expansion coefficient, the greater the difference in durability temperature.
[0003]
Because of such demands for heat resistance and thermal shock resistance, various ceramics have been proposed as a material for honeycomb carriers, but cordierite materials are mainly used. The main reason why cordierite materials are used is that cordierite has a high heat resistance of 1400 ° C., and has a very low thermal expansion coefficient and high thermal shock resistance among ceramics.
[0004]
However, cordierite material as a honeycomb carrier material has considerably superior properties in terms of heat resistance and thermal shock resistance, but on the other hand, nitrogen oxide (NOx), which is urgently required to be removed due to environmental problems, is used. When used as a catalyst carrier for purifying exhaust gas contained therein, it has an important difficulty. That is, as a catalyst for removing NOx in exhaust gas, a catalyst containing an alkali metal or alkaline earth metal component is usually used. In this case, a part of the alkali metal or alkaline earth metal is used at a high temperature. As a result, the cordierite penetrates into the carrier and reacts with the cordierite. As a result, the cordierite is deteriorated and the catalyst is lost. In order to prevent this, the catalyst surface is silica (SiO 2). 2 ) Has been proposed, but an extra process is required, which increases the cost.
[0005]
On the other hand, removal of NOx in exhaust gas is not possible with the direct injection of fuel into the engine or the lean burn of fuel, which has become the mainstream combustion method of automobiles in recent years due to improved fuel economy and environmental problems. It has become a particularly important issue over hydrocarbons and carbon monoxide. For this reason, the honeycomb carrier that supports the exhaust gas purification catalyst has been eagerly desired as a material to replace cordierite.
[0006]
As materials other than cordierite, Patent Document 1 lists ceramics such as silicon carbide, silicon nitride, mullite, aluminum titanate (aluminum titanate), lithium aluminum silicate, and the like. It is insufficient as a material. That is, silicon carbide, mullite, etc. have a large thermal expansion coefficient and poor thermal shock resistance. Silicon nitride, lithium aluminum silicate, etc. are insufficient in performance in terms of heat resistance.
[0007]
Aluminum titanate also has excellent stability, a very low thermal expansion coefficient, and excellent thermal shock resistance even at high temperatures exceeding 1700 ° C. However, on the other hand, because of the large anisotropy of the crystal structure, there is a drawback that the mechanical strength is small because the crystal grain boundary is likely to be displaced due to thermal stress. In addition, it is difficult to use as an exhaust gas filter that is mounted on an automobile or the like and is subjected to mechanical vibration load at high temperatures. Furthermore, these aluminum titanates have a problem that they usually have a decomposition region in a temperature range of 800 to 1280 ° C. and cannot be used continuously for a long time in a region including such a temperature range.
[Patent Document 1]
WO01 / 037771
[0008]
[Problems to be solved by the invention]
The present invention is a carrier for supporting a catalyst for purifying automobile exhaust gas, particularly containing NOx in the exhaust gas, and has excellent heat resistance, thermal shock resistance, mechanical strength, and thermal decomposition resistance, The present invention also provides a honeycomb carrier having high durability against erosion to a catalyst containing an alkali component and excellent in durability that does not deteriorate even after long-term use, and a method for producing the same.
[0009]
[Means for solving the problems]
In order to solve the above-mentioned problems, the present invention has earnestly studied focusing on aluminum magnesium titanate, and has obtained the following novel findings. That is, a honeycomb carrier using a sintered body obtained by firing a mixture obtained by adding a specific alkali feldspar to a mixture containing an Mg-containing compound, an Al-containing compound, and a Ti-containing compound has high heat resistance and low thermal expansion. Unlike the conventional aluminum magnesium titanate sintered body, while maintaining the thermal shock resistance based on the properties, it has high mechanical strength and resistance to thermal decomposition, and this sintered body is an alkali metal as a catalyst for removing NOx. In addition, when a catalyst containing alkaline earth metal components is used, it has been found that the catalyst can be used stably over a long period of time without deterioration as in the case of conventional cordierite materials.
[0010]
The present invention has been completed on the basis of the above-described novel findings and has the following gist.
(1) A honeycomb carrier for supporting a catalyst for purifying exhaust gas, the material of the honeycomb carrier being a composition formula: Mg x Al 2 (1-x) Ti (1 + x) O Five (Where, 0 <x <100) As an oxide conversion amount, a mixture containing an Mg-containing compound, an Al-containing compound, and a Ti-containing compound, which is contained in the same magnesium metal component ratio as Mg, Al, and Ti in the aluminum magnesium titanate represented by <1) Parts by mass and the composition formula: (Na y K 1-y ) AlSi Three O 8 Exhaust gas purification characterized by being an aluminum magnesium titanate sintered body obtained by firing a raw material mixture containing 1 to 10 parts by mass of alkali feldspar represented by the formula (0 ≦ y ≦ 1) at 1000 to 1700 ° C. Honeycomb carrier for catalyst.
(2) The honeycomb structure catalyst carrier has a wall thickness of 0.05 to 0.6 mm and a cell density of 15 to 124 cells / cm. 2 The partition wall has a porosity of 20 to 50% and a thermal expansion coefficient of 3.0 × 10 -6 K -1 The honeycomb carrier according to the above (1), which is the following.
(3) The catalyst carrier according to (1) or (2), wherein the catalyst contains an alkali metal or alkaline earth metal component for removing NOx in the exhaust gas.
(4) The honeycomb carrier according to the above (1), (2), or (3), wherein the exhaust gas is an exhaust gas of a vehicle in which fuel is directly injected into the engine or in which fuel is diluted.
(5) Composition formula: Mg x Al 2 (1-x) Ti (1 + x) O Five (Where, 0 <x <100) As an oxide conversion amount, a mixture containing an Mg-containing compound, an Al-containing compound, and a Ti-containing compound, which is contained in the same magnesium metal component ratio as Mg, Al, and Ti in the aluminum magnesium titanate represented by <1) Parts by mass and composition formula: (Na y K 1-y ) AlSi Three O 8 A raw material mixture containing 1 to 10 parts by mass of alkali feldspar represented by the formula (0 ≦ y ≦ 1) is prepared, a forming aid is added to the raw material mixture, and the mixture is kneaded and plasticized so as to be extruded. A method for manufacturing a honeycomb carrier for an exhaust gas purification catalyst, characterized by firing at 1000 to 1700 ° C after extrusion molding into a body.
(6) The manufacturing method as described in said (5) whose average particle diameter of each component contained in the said raw material mixture is 10 micrometers or less.
(7) A method for purifying exhaust gas in which exhaust gas is brought into contact with a honeycomb carrier carrying a catalyst for purifying exhaust gas, wherein the material of the honeycomb carrier has a composition formula: Mg x Al 2 (1-x) Ti (1 + x) O Five (Where, 0 <x <100) As an oxide conversion amount, a mixture containing an Mg-containing compound, an Al-containing compound, and a Ti-containing compound, which is contained in the same magnesium metal component ratio as Mg, Al, and Ti in the aluminum magnesium titanate represented by <1) Parts by mass and composition formula: (Na y K 1-y ) AlSi Three O 8 Purification of exhaust gas, which is a sintered body of aluminum magnesium titanate sintered at 1000 to 1700 ° C. containing 1 to 10 parts by mass of alkali feldspar represented by the formula (0 ≦ y ≦ 1) Method.
[0011]
The honeycomb carrier according to the present invention has excellent mechanical strength and thermal decomposition resistance, unlike the conventional aluminum magnesium titanate sintered body, while maintaining high heat resistance and thermal shock resistance as described above. Furthermore, although it is not necessarily clear whether it is deteriorated even when it is used as a catalyst carrier containing an alkali metal component to purify exhaust gas containing NOx, it is presumed that it is due to the following reason.
[0012]
That is, the crystal of aluminum magnesium titanate, which is the basic structure of the honeycomb carrier of the present invention, is grown in a state where the alkali feldspar is in a liquid phase due to the presence of alkali feldspar in the formation process. Formed and mechanical strength is improved. In addition, the Si component contained in alkali feldspar dissolves in the crystal lattice of aluminum magnesium titanate when aluminum magnesium titanate is formed by firing, but exists in 6-coordinate in the solid solution form of Si. Then, there are two types, that is, a solid solution within the crystal grains and a solid solution that exists in a four-coordinate configuration and dissolves at the crystal grain surface layer. This is supported by the results of observation by NMR (nuclear magnetic resonance) that Si in the aluminum magnesium titanate crystal exists in two states of 6-coordinate and 4-coordinate.
[0013]
That is, Si that is solid-solved inside the magnesium aluminum titanate crystal grains is hexacoordinated and is tetravalent, and is also paired with hexacoordinated and divalent Mg. Then, trivalent Al (total hexavalent) is replaced by two adjacent six-coordinations. The reason for this can be explained not only from the fact that the charge balance is maintained, but also from the correlation of the ion radius. In other words, Si 4+ And Mg 2+ The ionic radii are 0.54 and 0.86 そ れ ぞ れ, respectively, and the average ionic radius of both is 0.70 、. 3+ Approximate to the ion radius of 0.68 mm, Si 4+ And Mg 2+ Two Al with a pair of 3+ This is because the occupancy is in a solid solution state that is reasonable in terms of energy. In this way, due to the simultaneous presence of Si and Mg, aluminum magnesium titanate can suppress the diffusion of ions between cations even at high temperatures and has a stable crystal structure, so it is considered to exhibit excellent thermal decomposition resistance. It is done.
[0014]
On the other hand, Si dissolved in the surface layer portion of the aluminum magnesium titanate crystal grains is present as tetracoordinate rather than hexacoordinate. This is presumably because Si in the surface layer shares oxygen, that is, so-called partner cations are few, so that the bonding state of oxygen takes a more stable 4-coordination. Thus, Si that is solid-solved in the surface layer portion of the crystal grains becomes a state in which a crystal of aluminum magnesium titanate is simulated, and even when the honeycomb carrier of the present invention is used as a catalyst carrier containing an alkali metal, It has excellent corrosion resistance against the erosion of the carrier by the alkali component below, and is considered to bring about a characteristic that does not deteriorate even when used for a long time.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, as the material of the honeycomb structure catalyst carrier, the composition formula: Mg x Al 2 (1-x) Ti (1 + x) O Five (Where, 0 <x <100) As an oxide conversion amount, a mixture containing an Mg-containing compound, an Al-containing compound, and a Ti-containing compound, which is contained in the same magnesium metal component ratio as Mg, Al, and Ti in the aluminum magnesium titanate represented by <1) Parts by mass and composition formula: (Na y K 1-y ) AlSi Three O 8 An aluminum magnesium titanate sintered body obtained by firing a raw material mixture containing 1 to 10 parts by mass of alkali feldspar represented by (where 0 ≦ y ≦ 1) at 1000 to 1700 ° C. is used.
[0016]
As said Mg containing compound, Al containing compound, and Ti containing compound used as a raw material, if it is a component which can synthesize | combine aluminum magnesium titanate by baking, it can be used without limitation. The Mg-containing compound, the Al-containing compound, and the Ti-containing compound may not be separate compounds, and may be a compound containing two or more metal components. These raw material compounds are appropriately selected from those usually used as raw materials for various ceramics such as alumina ceramics, titania ceramics, magnesia ceramics, aluminum titanate ceramics, magnesium titanate ceramics, spinel ceramics, aluminum magnesium titanate ceramics. Can be used. Specific examples of such compounds include Al. 2 O Three TiO 2 , Oxides such as MgO, MgAl 2 O Four , Al 2 TiO Five , MgTiO Five , A compound oxide containing one or more metal components selected from the group consisting of Al, Ti and Mg, a composite oxide containing two or more metal components such as each spinel structure containing Mg and Ti ( And carbonates, nitrates, sulfates, etc.).
[0017]
The mixing ratio of the Mg-containing compound, Al-containing compound, and Ti-containing compound is that the ratio of the metal component contained in these compounds is the above-described composition formula: Mg x Al 2 (1-x) Ti (1 + x) O Five (Where, 0 <x What is necessary is just to make it the ratio similar to the metal component ratio of Mg, Al, and Ti in the aluminum magnesium titanate represented by <1), Preferably it becomes the same ratio. By mixing and using each of the above compounds at such a ratio, aluminum magnesium titanate having a metal component ratio similar to the metal component ratio in the mixture used as a raw material can be obtained.
[0018]
When obtaining the honeycomb carrier of the present invention, it is necessary to add alkali feldspar as an additive to the mixture containing the Mg-containing compound, Al-containing compound and Ti-containing compound. Alkali feldspar is a sintering aid for aluminum magnesium titanate and also serves to add Si component to aluminum magnesium titanate. y K 1-y ) AlSi Three O 8 It is represented by In the formula, y satisfies 0 ≦ y ≦ 1, preferably 0.1 ≦ y ≦ 1, and particularly preferably 0.15 ≦ y ≦ 0.85. Alkaline feldspar having a y value in this range has a low melting point and is particularly effective in promoting the sintering of aluminum magnesium titanate.
[0019]
The amount of alkali feldspar used may be about 1 to 10 parts by mass with respect to 100 parts by mass of the total value of each compound of Mg-containing compound, Al-containing compound and Ti-containing compound used as raw materials, The amount is preferably about 3 to 5 parts by mass. In this case, the total amount of the raw material mixture converted into an oxide means that after performing heat treatment for removing moisture and organic matter contained in the raw material mixture, The mass before sintering after sintering.
[0020]
A raw material mixture obtained by adding alkali feldspar to a mixture containing an Mg-containing compound, an Al-containing compound and a Ti-containing compound can improve the properties of a sintered body obtained by adding another sintering aid as necessary. Other sintering aids include, for example, Mg-containing spinel type oxides, MgCO Three , MgO and the like.
[0021]
The raw material mixture is thoroughly mixed and pulverized. The mixing and pulverization of the raw material mixture is not particularly limited and is performed according to a known method. For example, a ball mill, a medium stirring mill, or the like may be used. The degree of pulverization of the raw material mixture is not particularly limited, but the average particle size is preferably 10 μm or less, particularly preferably 1 to 5 μm. The raw material mixture is preferably as small as possible as long as secondary particles are not formed.
[0022]
Preferably, a molding aid can be blended in the raw material mixture. As molding aids, known ones such as binders, pore formers, mold release agents, antifoaming agents, and peptizers can be used. As the binder, polyvinyl alcohol, microwax emulsion, methylcellulose, carboxymethylcellulose and the like are preferable. As the pore former, activated carbon, coke, polyethylene resin, starch, graphite and the like are preferable. As the release agent, stearic acid emulsion and the like are preferable, as the antifoaming agent, n-octyl alcohol, octylphenoxyethanol and the like are preferable, and as the peptizer, diethylamine, triethylamine and the like are preferable.
[0023]
The amount of the molding aid used is not particularly limited, but in the case of the present invention, a total amount of 100 parts by mass in which each compound of Mg-containing compound, Al-containing compound and Ti-containing compound used as raw materials is converted into an oxide. On the other hand, it is preferable that all be within the following ranges in terms of solid matter. That is, the binder is preferably about 0.2 to 0.6 parts by mass, the pore former is preferably about 20 to 50 parts by mass, the mold release agent is preferably about 0.2 to 0.7 parts by mass, and the defoaming agent It is preferable to use about 0.5 to 1.5 parts by weight of the agent and preferably about 0.5 to 1.5 parts by weight of the peptizer.
[0024]
The raw material mixture to which the forming aid is added is mixed, kneaded, and plasticized so as to be extrudable and formed into a honeycomb body by extrusion. A known method can be used as the extrusion method, and the cross-sectional shape of the honeycomb cell may be any of a circle, an ellipse, a rectangle, and a triangle. Further, the entire form of the honeycomb body may be a cylindrical body or a rectangular tube body. The formed honeycomb is preferably dried and then fired at 1000-1700 ° C, preferably 1250-1450 ° C. There is no particular limitation on the firing atmosphere, and an oxygen-containing atmosphere such as air that is usually employed is preferable. The firing time may be fired until the sintering proceeds sufficiently, and usually about 1 to 20 hours is employed.
[0025]
There is no restriction | limiting in particular also about the temperature increase rate and temperature decrease rate in the case of the said baking, What is necessary is just to set suitably the conditions which a crack etc. do not enter in the obtained sintered compact. For example, it is preferable to gradually raise the temperature without rapidly raising the temperature in order to sufficiently remove moisture, binders and other molding aids contained in the raw material mixture. Further, before heating to the above-described firing temperature, titanic acid is preferably obtained by performing preliminary sintering at a moderate temperature rise of about 10 to 30 hours, if necessary, preferably in a temperature range of about 500 to 1000 ° C. It is possible to relieve stress in the sintered body that causes cracks when aluminum magnesium is formed, and to suppress the generation of cracks in the sintered body and obtain a dense and uniform sintered body. .
[0026]
The sintered body thus obtained has a composition formula: Mg x Al 2 (1-x) Ti (1 + x) O Five (Where 0 <x Using aluminum magnesium titanate represented by <1) as a basic component, the Si component contained in alkali feldspar is dissolved in the crystal lattice of aluminum magnesium titanate. As described above, such a sintered body has high heat resistance and thermal shock resistance, and has a stable crystal structure, thereby having excellent mechanical strength and thermal decomposition resistance. It becomes.
[0027]
As a result, the honeycomb body made of this sintered body has a wall thickness of, for example, 0.05 to 0.6 mm, and a cell density of, for example, 15 to 124 cells / cm. 2 The thin-walled honeycomb structure. And the porosity of a partition is 20 to 50%, for example, and a thermal expansion coefficient is 3.0 * 10, for example. -6 K -1 It is as follows. This honeycomb body can be used stably even at a high temperature of about 1600 ° C. from room temperature because the thermal decomposition reaction of aluminum magnesium titanate is suppressed.
[0028]
The honeycomb body is used as a catalyst carrier for purifying various exhaust gases containing harmful components such as hydrocarbons, carbon monoxide, NOx, SOx, in particular, exhaust gases for automobiles containing NOx in the exhaust gas. The In particular, since the honeycomb carrier of the present invention has stability against alkali at a high temperature, NOx is contained in the exhaust gas at a relatively high concentration, or the fuel is directly injected into the engine or the fuel is diluted and burned. It is effective against the exhaust gas of the automobile of the system.
[0029]
As the type of catalyst supported on the carrier, various known ones such as a so-called three-way catalyst for removing conventional hydrocarbons and carbon monoxide can be used. In the present invention, however, NOx in exhaust gas is removed. It is particularly effective for a catalyst containing an alkali metal or alkaline earth metal component. Among the alkali metals and alkaline earth metals, the carrier of the present invention is effective for catalysts containing potassium and barium, particularly potassium, which are effective for removing NOx.
[0030]
A known means is adopted as a method for supporting the catalyst on the honeycomb body of the present invention. When the catalyst is supported, a material having a large specific surface area, such as alumina or silica, may be interposed as required to improve the loading rate. That is, alumina or silica can be supported on the honeycomb carrier, and the catalyst can be supported on the supported alumina or silica. The honeycomb body supporting the catalyst is preferably used by being mounted in a can body using an appropriate holding material.
[0031]
【Example】
EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but it is needless to say that the present invention should not be construed as being limited thereto.
[0032]
Example 1
26.7 mass% (20 mol%) of easily sinterable α-type alumina, 62.8 mass% (60 mol%) of anatase type titanium oxide, and periclase type magnesium oxide existing as a natural mineral To 100 parts by mass of a mixture consisting of 10.5% by mass (20 mol%), (Na 0.6 K 0.4 ) AlSi Three O 8 4 parts by weight of the alkali feldspar represented by the formula, 0.25 parts by weight of polyvinyl alcohol as a binder, 1 part by weight of diethylamine as a peptizer, 0.5 parts by weight of polypropylene glycol as an antifoaming agent, and as a pore-forming agent, 35 parts by mass of activated carbon having a particle size of 30 μm or less was added and mixed for 3 hours with a ball mill, and then dried for 12 hours or more with a 120 ° C. dryer to obtain a raw material powder.
[0033]
The obtained raw material powder was pulverized to an average particle size of about 5 μm and extruded using a vacuum extrusion molding machine (Miyazaki Tekko Co., Ltd.). The wall thickness was 0.1 mm and the cell density was 93 cells / cm. 2 A cylindrical honeycomb body having a square cell shape with a diameter of 129 mm and a length of 150 mm was obtained. The honeycomb body was dried and then fired at 1400 ° C. for 4 hours in the air. Then, the sintered compact was obtained by standing to cool.
[0034]
Comparative Example 1
A honeycomb-shaped sintered body made of an aluminum magnesium titanate sintered body was obtained in the same manner as in Example 1 except that alkali feldspar was not used.
[0035]
Comparative Example 2
As a material for honeycomb filters, cordierite powder (2MgO · 2Al 2 O Three . ・ 5SiO 2 And a honeycomb having the same shape as that of Example 1 was manufactured by carrying out by an existing method.
[0036]
[Characteristic test on honeycomb sintered body]
For the honeycomb sintered bodies of Example 1 and Comparative Examples 1 and 2, the porosity (%), the thermal expansion coefficient from room temperature to 800 ° C. (× 10 -6 K -1 ), Thermal shock resistance (° C.), softening temperature (° C.), and compressive strength (MPa) measured by an underwater dropping method, and the results are shown in Table 1. The porosity was measured by a method in accordance with JIS R1634, the thermal expansion coefficient in accordance with JIS R1618, the thermal shock resistance in JIS R1648, the softening temperature in JIS R2209, and the compressive strength in accordance with JIS R1608. As for the compressive strength, from each honeycomb sintered body, a rectangular tube specimen having a length of 15 mm in the length direction and a length of 15 mm is cut out from each of the vertical and horizontal cell numbers of the cylinder cross section. Measurements were made from three directions: an axial direction, (B) a vertical direction (tangential), and (C) a diagonal direction of 45 degrees with respect to the length axis.
[0037]
[Table 1]
[Pyrolysis resistance test]
Cut out test pieces each having a length of 10 mm, a width of 10 mm, and a length of 10 mm from the honeycomb filter of Example 1 and hold in a high-temperature atmosphere at 1100 ° C., and examine the time-dependent change in the residual ratio α (%) of aluminum magnesium titanate. The thermal decomposition resistance test was conducted.
[0039]
The residual rate of aluminum magnesium titanate was determined from the spectrum of X-ray diffraction measurement (XRD) by the following method.
First, when magnesium magnesium titanate is thermally decomposed, MgAl 2 O Four (Spinel) and TiO 2 (Rutile), the integrated intensity (I of the diffraction peak on the (110) plane of rutile) TiO2 (110) ) And the integrated intensity of the diffraction peak of the (023) plane of aluminum magnesium titanate (I MAT (023) The strength ratio R of aluminum magnesium titanate to rutile was determined from the following formula.
R = I MAT (023) / (I MAT (023) + I TiO2 (110) )
Furthermore, the strength ratio R of aluminum magnesium titanate to rutile is also applied to the sintered body before heat treatment at 1100 ° C. in the same manner. 0 Asked. Next, R and R determined by the above method 0 The residual rate α (%) of aluminum magnesium titanate was determined from the following formula.
α = (R / R 0 ) × 100
[0040]
FIG. 1 is a graph showing the change over time in the residual rate α of aluminum magnesium titanate for the sintered bodies of Example 1 and Comparative Example 1. As is apparent from FIG. 1, the sintered body of Example 1 has a higher residual rate α of aluminum magnesium titanate over a long period of time and is excellent in thermal decomposition resistance as compared with the sintered body of Comparative Example 1. I understand that.
[0041]
[Alkali resistance test of honeycomb body]
In order to investigate the corrosion resistance of the honeycomb body with respect to the potassium-containing catalyst which is a catalyst for removing NOx from automobile exhaust gas, the following test was conducted. The operating temperature of the honeycomb carrier for automobile exhaust gas is in the range of room temperature to 850 ° C., and the potassium concentration of the potassium-containing catalyst is not so high, but in this test, a potassium nitrate aqueous solution having a concentration of 1 mol / liter. An accelerated test under severe conditions was performed in which a test piece immersed in and dried in a furnace was held in a furnace maintained at a temperature of 900 ° C. for a long time.
[0042]
[Test method]
A test piece having a cross section of 30 mm square and a length of 50 mm was cut out from each honeycomb body of Example 1 and Comparative Example 2, and this test piece was immersed in an aqueous potassium nitrate solution having a concentration of 1 mol / liter at room temperature for 10 to 60 minutes. Then, the test piece was dried at 70 ° C. for 1 hour. The dried honeycomb body was inserted into a tubular furnace having an inner diameter of 5 cm and a length of 42 cm, and air containing 10% water was allowed to flow into the tubular furnace at 25 cc / min and maintained for a predetermined time under the following conditions. did. Thereafter, the honeycomb body taken out from the tubular furnace was subjected to XRD measurement to examine the alteration of the honeycomb body material. In addition, the air containing 10% of water flowing into the tubular furnace was prepared by passing air through a water tank controlled at 60 ° C. The test results are shown in Table 2.
Retention condition
Furnace temperature: 900 ° C, Furnace temperature rise / fall rate: 100 ° C / hour
Holding time: 50 hours, 100 hours, 150 hours, 200 hours
[0043]
[Table 2]
[0044]
【The invention's effect】
Unlike the conventional aluminum magnesium titanate sintered body, the honeycomb carrier made of the aluminum magnesium titanate sintered body of the present invention has high mechanical strength while maintaining the thermal shock resistance based on high heat resistance and low thermal expansion. In addition, it has thermal decomposition resistance and excellent corrosion resistance to the catalyst. As a result, it is effective as a carrier for supporting a catalyst for purifying exhaust gas from any combustion source of the fixed body and the moving body, particularly NOx contained in the exhaust gas, and purifying exhaust gas for automobiles.
[Brief description of the drawings]
FIG. 1 shows the change over time in the residual ratio α of aluminum magnesium titanate for the sintered bodies of Example 1 and Comparative Example 1 of the present invention.
Claims (7)
Priority Applications (8)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2003203271A JP4609831B2 (en) | 2003-07-29 | 2003-07-29 | Honeycomb carrier for exhaust gas purification catalyst and manufacturing method thereof |
| CA002533387A CA2533387A1 (en) | 2003-07-29 | 2004-07-29 | Honeycomb carrier for exhaust gas-cleaning catalyst and process for its production |
| CN2007100971354A CN101091925B (en) | 2003-07-29 | 2004-07-29 | Honeycomb carrier for exhaust gas clarification catalyst and method for production thereof |
| CNB2004800183312A CN100400464C (en) | 2003-07-29 | 2004-07-29 | Honeycomb carrier for exhaust gas clarification catalyst and method for production thereof |
| US10/566,270 US8685363B2 (en) | 2003-07-29 | 2004-07-29 | Honeycomb carrier for exhaust gas clarification catalyst and method for production thereof |
| EP20040771230 EP1652830A4 (en) | 2003-07-29 | 2004-07-29 | Honeycomb carrier for exhaust gas clarification catalyst and method for production thereof |
| KR1020057023260A KR101154903B1 (en) | 2003-07-29 | 2004-07-29 | Honeycomb carrier for exhaust gas clarification catalyst and method for production thereof |
| PCT/JP2004/011203 WO2005009918A1 (en) | 2003-07-29 | 2004-07-29 | Honeycomb carrier for exhaust gas clarification catalyst and method for production thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2003203271A JP4609831B2 (en) | 2003-07-29 | 2003-07-29 | Honeycomb carrier for exhaust gas purification catalyst and manufacturing method thereof |
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| Publication Number | Publication Date |
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| JP2005046667A JP2005046667A (en) | 2005-02-24 |
| JP4609831B2 true JP4609831B2 (en) | 2011-01-12 |
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| Application Number | Title | Priority Date | Filing Date |
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| JP2003203271A Expired - Fee Related JP4609831B2 (en) | 2003-07-29 | 2003-07-29 | Honeycomb carrier for exhaust gas purification catalyst and manufacturing method thereof |
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| JP (1) | JP4609831B2 (en) |
| CN (1) | CN100400464C (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0654477A (en) * | 1992-07-28 | 1994-02-25 | Sanyo Electric Co Ltd | Bearing device of motor |
| FR2933398B1 (en) * | 2008-07-04 | 2011-02-18 | Saint Gobain Ct Recherches | OXIDE-FILLED GRAINS COMPRISING AL, TI AND MG AND CERAMIC PRODUCTS COMPRISING SUCH GRAINS |
| US20110156323A1 (en) * | 2008-09-04 | 2011-06-30 | Sumitomo Chemical Company, Limited | Process for producing aluminum titanate-based ceramics |
| JP5368081B2 (en) * | 2008-12-25 | 2013-12-18 | 住友化学株式会社 | Method for producing aluminum titanate-based fired body |
| WO2012070386A1 (en) * | 2010-11-24 | 2012-05-31 | 住友化学株式会社 | Honeycomb filter |
| JP2014018768A (en) * | 2012-07-20 | 2014-02-03 | Sumitomo Chemical Co Ltd | Exhaust gas purifying system |
| CN103566920B (en) * | 2012-08-01 | 2016-05-25 | 通用电气公司 | Material and the exhaust apparatus and the method that use it |
| EP3150268A1 (en) * | 2014-05-30 | 2017-04-05 | Sumitomo Chemical Company Limited | Honeycomb filter intermediate, honeycomb filter, and processes for producing said intermediate and said filter |
| CN105924202B (en) * | 2016-04-28 | 2019-01-04 | 河南省格林沃特环保科技有限公司 | A kind of diesel engine vent gas post-processing technology of preparing of SCR catalyst carrier |
| WO2018198999A1 (en) * | 2017-04-26 | 2018-11-01 | 大塚化学株式会社 | Honeycomb structure and exhaust gas purification device |
| CN114515570A (en) * | 2022-01-30 | 2022-05-20 | 华南理工大学 | Catalyst for ethyl acetate oxidation molding and preparation method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4950492B2 (en) * | 2003-07-11 | 2012-06-13 | オーセラ株式会社 | Manufacturing method of honeycomb filter for exhaust gas purification |
| US7550025B2 (en) * | 2003-08-22 | 2009-06-23 | Ohcera Co., Ltd. | Honeycomb filter for clarifying exhaust gas and method for manufacture thereof |
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| JPS56134560A (en) * | 1980-03-19 | 1981-10-21 | Ngk Insulators Ltd | Low expansion ceramics and manufacture |
| JPS573767A (en) * | 1980-06-04 | 1982-01-09 | Nippon Toki Kk | High temperature-stable high strength aluminium titanate sintered body |
| JPS62256757A (en) * | 1986-01-28 | 1987-11-09 | 松下電器産業株式会社 | Manufacture of thermal shock resistant ceramics |
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| JP2002145659A (en) * | 2000-11-08 | 2002-05-22 | Tsutomu Fukuda | Method for producing aluminum titanate based sintered compact |
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|---|---|
| JP2005046667A (en) | 2005-02-24 |
| CN100400464C (en) | 2008-07-09 |
| CN1812945A (en) | 2006-08-02 |
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