JPH0739758A - Catalyst for cleaning exhaust and cleaning method with the same - Google Patents
Catalyst for cleaning exhaust and cleaning method with the sameInfo
- Publication number
- JPH0739758A JPH0739758A JP5188455A JP18845593A JPH0739758A JP H0739758 A JPH0739758 A JP H0739758A JP 5188455 A JP5188455 A JP 5188455A JP 18845593 A JP18845593 A JP 18845593A JP H0739758 A JPH0739758 A JP H0739758A
- Authority
- JP
- Japan
- Prior art keywords
- catalyst
- exhaust gas
- platinum
- nitrogen oxides
- hydrocarbons
- 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.)
- Pending
Links
- 239000003054 catalyst Substances 0.000 title claims abstract description 62
- 238000000034 method Methods 0.000 title claims abstract description 17
- 238000004140 cleaning Methods 0.000 title abstract 4
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 claims abstract description 66
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims abstract description 59
- 229910052697 platinum Inorganic materials 0.000 claims abstract description 30
- 229910052723 transition metal Inorganic materials 0.000 claims abstract description 19
- 150000003624 transition metals Chemical class 0.000 claims abstract description 18
- 229930195733 hydrocarbon Natural products 0.000 claims abstract description 15
- 150000002430 hydrocarbons Chemical class 0.000 claims abstract description 15
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 14
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 14
- 239000001301 oxygen Substances 0.000 claims abstract description 14
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims abstract description 10
- 229910002091 carbon monoxide Inorganic materials 0.000 claims abstract description 10
- 239000003638 chemical reducing agent Substances 0.000 claims abstract description 9
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 claims abstract description 6
- 229910052717 sulfur Inorganic materials 0.000 claims abstract description 6
- 239000011593 sulfur Substances 0.000 claims abstract description 6
- 150000001298 alcohols Chemical class 0.000 claims abstract description 3
- 239000007789 gas Substances 0.000 claims description 51
- 238000000746 purification Methods 0.000 claims description 15
- 238000010531 catalytic reduction reaction Methods 0.000 claims description 4
- 150000003464 sulfur compounds Chemical class 0.000 claims description 4
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 24
- 238000011156 evaluation Methods 0.000 description 15
- 229910052742 iron Inorganic materials 0.000 description 13
- 230000000694 effects Effects 0.000 description 12
- 239000007864 aqueous solution Substances 0.000 description 8
- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Substances [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 8
- 239000010949 copper Substances 0.000 description 7
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 6
- 229910052802 copper Inorganic materials 0.000 description 6
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 5
- 229910052759 nickel Inorganic materials 0.000 description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 239000000470 constituent Substances 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- 229910052721 tungsten Inorganic materials 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 3
- QMMFVYPAHWMCMS-UHFFFAOYSA-N Dimethyl sulfide Chemical compound CSC QMMFVYPAHWMCMS-UHFFFAOYSA-N 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 3
- 229910021536 Zeolite Inorganic materials 0.000 description 3
- 229910021529 ammonia Inorganic materials 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 description 3
- 238000005470 impregnation Methods 0.000 description 3
- 150000002739 metals Chemical class 0.000 description 3
- QQONPFPTGQHPMA-UHFFFAOYSA-N propylene Natural products CC=C QQONPFPTGQHPMA-UHFFFAOYSA-N 0.000 description 3
- 125000004805 propylene group Chemical group [H]C([H])([H])C([H])([*:1])C([H])([H])[*:2] 0.000 description 3
- 239000011734 sodium Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 238000005987 sulfurization reaction Methods 0.000 description 3
- 229910052720 vanadium Inorganic materials 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 239000010457 zeolite Substances 0.000 description 3
- 229910052684 Cerium Inorganic materials 0.000 description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 2
- 229910052777 Praseodymium Inorganic materials 0.000 description 2
- 229910002836 PtFe Inorganic materials 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 229910052783 alkali metal Inorganic materials 0.000 description 2
- 150000001340 alkali metals Chemical class 0.000 description 2
- 229910052784 alkaline earth metal Inorganic materials 0.000 description 2
- 150000001342 alkaline earth metals Chemical class 0.000 description 2
- VXAUWWUXCIMFIM-UHFFFAOYSA-M aluminum;oxygen(2-);hydroxide Chemical compound [OH-].[O-2].[Al+3] VXAUWWUXCIMFIM-UHFFFAOYSA-M 0.000 description 2
- 229910052788 barium Inorganic materials 0.000 description 2
- 229910052791 calcium Inorganic materials 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 229910052804 chromium Inorganic materials 0.000 description 2
- 229910017052 cobalt Inorganic materials 0.000 description 2
- 239000010941 cobalt Substances 0.000 description 2
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 2
- 238000002485 combustion reaction Methods 0.000 description 2
- VCJMYUPGQJHHFU-UHFFFAOYSA-N iron(3+);trinitrate Chemical compound [Fe+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O VCJMYUPGQJHHFU-UHFFFAOYSA-N 0.000 description 2
- 238000011068 loading method Methods 0.000 description 2
- 229910052749 magnesium Inorganic materials 0.000 description 2
- 229910052748 manganese Inorganic materials 0.000 description 2
- 229910052750 molybdenum Inorganic materials 0.000 description 2
- 229910052758 niobium Inorganic materials 0.000 description 2
- 239000010955 niobium Substances 0.000 description 2
- 229910017604 nitric acid Inorganic materials 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- PXXKQOPKNFECSZ-UHFFFAOYSA-N platinum rhodium Chemical compound [Rh].[Pt] PXXKQOPKNFECSZ-UHFFFAOYSA-N 0.000 description 2
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 2
- 229910052700 potassium Inorganic materials 0.000 description 2
- 238000006722 reduction reaction Methods 0.000 description 2
- 229910052703 rhodium Inorganic materials 0.000 description 2
- 239000010948 rhodium Substances 0.000 description 2
- 229910052707 ruthenium Inorganic materials 0.000 description 2
- 229910052709 silver Inorganic materials 0.000 description 2
- 229910052708 sodium Inorganic materials 0.000 description 2
- 229910052979 sodium sulfide Inorganic materials 0.000 description 2
- GRVFOGOEDUUMBP-UHFFFAOYSA-N sodium sulfide (anhydrous) Chemical compound [Na+].[Na+].[S-2] GRVFOGOEDUUMBP-UHFFFAOYSA-N 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 2
- 239000010937 tungsten Substances 0.000 description 2
- 229910052725 zinc Inorganic materials 0.000 description 2
- 229910000873 Beta-alumina solid electrolyte Inorganic materials 0.000 description 1
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- 229910002651 NO3 Inorganic materials 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 1
- 150000004645 aluminates Chemical class 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 125000004432 carbon atom Chemical group C* 0.000 description 1
- 238000003421 catalytic decomposition reaction Methods 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- UFMZWBIQTDUYBN-UHFFFAOYSA-N cobalt dinitrate Chemical compound [Co+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O UFMZWBIQTDUYBN-UHFFFAOYSA-N 0.000 description 1
- 229910001981 cobalt nitrate Inorganic materials 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 229910052878 cordierite Inorganic materials 0.000 description 1
- XAYGUHUYDMLJJV-UHFFFAOYSA-Z decaazanium;dioxido(dioxo)tungsten;hydron;trioxotungsten Chemical compound [H+].[H+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.[O-][W]([O-])(=O)=O.[O-][W]([O-])(=O)=O.[O-][W]([O-])(=O)=O.[O-][W]([O-])(=O)=O.[O-][W]([O-])(=O)=O.[O-][W]([O-])(=O)=O XAYGUHUYDMLJJV-UHFFFAOYSA-Z 0.000 description 1
- 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 1
- 238000001035 drying Methods 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 239000006260 foam Substances 0.000 description 1
- 238000004817 gas chromatography Methods 0.000 description 1
- FAHBNUUHRFUEAI-UHFFFAOYSA-M hydroxidooxidoaluminium Chemical compound O[Al]=O FAHBNUUHRFUEAI-UHFFFAOYSA-M 0.000 description 1
- 150000002484 inorganic compounds Chemical class 0.000 description 1
- 229910052746 lanthanum Inorganic materials 0.000 description 1
- JCCNYMKQOSZNPW-UHFFFAOYSA-N loratadine Chemical compound C1CN(C(=O)OCC)CCC1=C1C2=NC=CC=C2CCC2=CC(Cl)=CC=C21 JCCNYMKQOSZNPW-UHFFFAOYSA-N 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- KBJMLQFLOWQJNF-UHFFFAOYSA-N nickel(ii) nitrate Chemical compound [Ni+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O KBJMLQFLOWQJNF-UHFFFAOYSA-N 0.000 description 1
- 229910000510 noble metal Inorganic materials 0.000 description 1
- 150000002898 organic sulfur compounds Chemical class 0.000 description 1
- 229910052763 palladium Inorganic materials 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000002243 precursor Substances 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 229910052761 rare earth metal Inorganic materials 0.000 description 1
- 150000002910 rare earth metals Chemical class 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 1
- 230000001988 toxicity Effects 0.000 description 1
- 231100000419 toxicity Toxicity 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、自動車等の内燃機関の
排ガス、ボイラー、硝酸工場等の排ガスの浄化に関し、
更には希薄燃焼ガソリンエンジン、ディーゼルエンジン
等の排ガスのような酸素過剰排ガス中の、窒素酸化物の
接触還元又は分解による排ガス浄化用の白金系触媒並び
に該触媒を用いた排ガス浄化法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to purification of exhaust gas from internal combustion engines such as automobiles, exhaust gas from boilers, nitric acid plants, etc.
Further, the present invention relates to a platinum-based catalyst for purifying exhaust gas by catalytic reduction or decomposition of nitrogen oxide in oxygen-rich exhaust gas such as exhaust gas of lean burn gasoline engine, diesel engine and the like, and exhaust gas purification method using the catalyst.
【０００２】[0002]
【従来の技術】酸素過剰雰囲気の下での窒素酸化物の接
触還元による浄化の方法としては、アンモニアを還元剤
として用いる選択的還元法がよく知られており、ボイラ
ー排ガス中の窒素酸化物の除去などに現在広く用いられ
ている。この方法では、通常酸化チタンに担持したバナ
ジウム触媒が用いられているが、アルミナに担持した白
金触媒、その他多くの触媒も研究されており、夫々に活
性を有することが知られている。2. Description of the Related Art A selective reduction method using ammonia as a reducing agent is well known as a method for purifying nitrogen oxides by catalytic reduction in an oxygen excess atmosphere. It is currently widely used for removal. In this method, a vanadium catalyst supported on titanium oxide is usually used, but a platinum catalyst supported on alumina and many other catalysts have also been studied, and it is known that each has an activity.
【０００３】一方、自動車等の内燃機関の排ガス用に
は、一酸化炭素、炭化水素類及び窒素酸化物の三者を同
時に除去する白金−ロジウム（Ｐｔ−Ｒｈ）系等の貴金
属を主体とする三元触媒が用いられているが、この場合
は、排ガス中の酸素含有量のコントロールが必須条件と
なり、例えば、酸素過剰の状態では窒素酸化物の還元は
殆ど行われず、脱硝触媒としては全く効果のなくなるこ
とが知られている。On the other hand, for exhaust gas from internal combustion engines such as automobiles, a noble metal such as a platinum-rhodium (Pt-Rh) system which mainly removes carbon monoxide, hydrocarbons and nitrogen oxides is mainly used. Although a three-way catalyst is used, in this case, the control of the oxygen content in the exhaust gas is an essential condition, for example, in the state of excess oxygen, almost no reduction of nitrogen oxides is performed, and it is completely effective as a denitration catalyst It is known to disappear.
【０００４】本発明の課題である希薄燃焼ガソリンエン
ジン、又はディーゼルエンジンよりの排ガスのような、
酸素の過剰な排ガス中の主として窒素酸化物の除去にお
いては、還元剤としてのアンモニアの使用は、その毒
性、取扱の困難性等から望ましくはないものである。ま
た、従来の三元触媒は、活性上の問題があるために酸素
過剰排ガスの浄化には使用できない。The exhaust gas from the lean burn gasoline engine or diesel engine which is the subject of the present invention,
In the removal of mainly nitrogen oxides in exhaust gas with excess oxygen, the use of ammonia as a reducing agent is not desirable because of its toxicity, handling difficulty, and the like. Further, the conventional three-way catalyst cannot be used for purification of oxygen-excess exhaust gas because of problems in activity.
【０００５】上記のような情勢から、アンモニアを使用
せずにこれらの排ガスを浄化することのできる触媒の開
発が急務の問題となり、既に多くの提案がなされてい
る。一例を挙げると、特開平４−２９８２３５号公報に
は、酸素存在下において、効率良く窒素酸化物を接触還
元する触媒として、Ｋ，Ｎａ，Ｃａ，Ｍｇ，Ｂａ，Ｌ
ａ，Ｃｅ，Ｐｒ等のアルミン酸塩を触媒成分として含有
する触媒、及びＸ・β−Ａｌ2 Ｏ3 で表わされる物質
（ＸはＫ，Ｎａ，Ｃａ，Ｍｇ，Ｂａ，Ｌａ，Ｃｅ，Ｐｒ
を表わす）を触媒成分として含有する触媒が提案されて
おり、更にこれらの触媒に、Ｖ，Ｃｒ，Ｍｎ，Ｆｅ，Ｃ
ｏ，Ｎｉ，Ｃｕ，Ｚｎ，Ｎｂ，Ｍｏ，Ｗ，Ｒｕ，Ｒｈ，
Ｐｄ，Ａｇ，Ｐｔ等の少なくとも一種の金属、その酸化
物及び／又は硫酸塩を含有せしめると良いことが述べら
れている。From the above circumstances, the development of a catalyst capable of purifying these exhaust gases without using ammonia has become an urgent issue, and many proposals have already been made. As an example, Japanese Patent Laid-Open No. 4-298235 discloses K, Na, Ca, Mg, Ba, L as catalysts for efficiently catalytically reducing nitrogen oxides in the presence of oxygen.
a, a catalyst containing an aluminate such as Ce, Pr as a catalyst component, and a substance represented by X.β-Al 2 O 3 (X is K, Na, Ca, Mg, Ba, La, Ce, Pr
Is represented as a catalyst component, and V, Cr, Mn, Fe and C are added to these catalysts.
o, Ni, Cu, Zn, Nb, Mo, W, Ru, Rh,
It is described that it is preferable to contain at least one metal such as Pd, Ag and Pt, its oxide and / or sulfate.
【０００６】また、特開平５−４９９３３号公報には、
アルカリ金属及び／又はアルカリ土類金属を担持したゼ
オライト触媒と、コバルトを担持したゼオライト触媒と
を、前者を排気ガス流入側に、また後者を排気ガス流出
側に配設して排気ガス浄化を行なう場合に、酸素過剰雰
囲気中では、炭素数の大きい炭化水素類を還元剤として
使用しても、窒素酸化物の浄化活性が低下しないことが
開示されており、モノリス状、ペレット状、等の耐火性
基材上にコートして用いられることが述べられている。Further, Japanese Patent Laid-Open No. 5-49933 discloses that
The zeolite catalyst supporting an alkali metal and / or an alkaline earth metal and the zeolite catalyst supporting cobalt are disposed on the exhaust gas inflow side and the latter on the exhaust gas outflow side to purify the exhaust gas. In this case, it is disclosed that in an oxygen-excess atmosphere, even if a hydrocarbon having a large number of carbon atoms is used as a reducing agent, the purifying activity of nitrogen oxides does not decrease. It is described that it is used by coating on a permeable substrate.
【０００７】[0007]
【発明が解決しようとする課題】酸素過剰雰囲気の下で
の窒素酸化物の除去のための触媒については、前述の如
く多くの触媒が提案されてはいるが、実用化されている
ものは皆無に等しい。即ち、高温域のみならず低温域に
おいても優れた活性を示し、且つ使用条件下において活
性が低下しないという極めて困難な条件をクリアするこ
とのできる触媒が見出されていないからである。白金系
触媒は概して低温活性には優れた特性を示すが、特定の
使用条件の下では急激な活性低下が起こるという実用上
の問題点がある。As a catalyst for removing nitrogen oxides in an oxygen excess atmosphere, many catalysts have been proposed as described above, but none have been put into practical use. be equivalent to. That is, no catalyst has been found which exhibits excellent activity not only in the high temperature region but also in the low temperature region and which can satisfy the extremely difficult condition that the activity does not decrease under the use conditions. Platinum-based catalysts generally exhibit excellent properties for low-temperature activity, but there is a practical problem that the activity decreases rapidly under specific use conditions.
【０００８】本発明は、酸素過剰排ガス、特に希薄燃焼
ガソリンエンジン、ディーゼルエンジン等の排ガス中
の、主として窒素酸物除去のための、白金及び一種以上
の遷移金属を主成分とする安定で高活性な排ガス浄化触
媒、並びに該触媒を用いる排ガス浄化法の提供を目的と
するものである。The present invention is a stable and highly active compound containing platinum and at least one transition metal as a main component, mainly for removing nitrogen oxides in oxygen-rich exhaust gas, particularly lean-burn gasoline engine, diesel engine and other exhaust gas. The present invention aims to provide an exhaust gas purifying catalyst and an exhaust gas purifying method using the catalyst.
【０００９】[0009]
【課題を解決するための手段】本発明者らは、上記の課
題を解決するべく鋭意検討し本発明を完成するに至っ
た。即ち、本発明の触媒は、窒素酸化物、一酸化炭素及
び炭化水素類を含む酸素過剰の排ガスから、窒素酸化
物、一酸化炭素及び炭化水素類を除去するための白金及
び一種以上の遷移金属を主成分とする排ガス浄化触媒で
あって、前記白金及び遷移金属が硫黄と多孔質担体上に
共存してなることを特徴とするものである。Means for Solving the Problems The inventors of the present invention have made extensive studies in order to solve the above problems and completed the present invention. That is, the catalyst of the present invention is platinum and one or more transition metals for removing nitrogen oxides, carbon monoxide and hydrocarbons from oxygen-excess exhaust gas containing nitrogen oxides, carbon monoxide and hydrocarbons. An exhaust gas purifying catalyst containing as a main component, the platinum and the transition metal coexisting with sulfur on a porous carrier.
【００１０】また、本発明の排ガス浄化法は、本発明の
触媒を用いて、希薄燃焼ガソリンエンジン及びディーゼ
ルエンジン排ガス等の酸素過剰排ガス中の窒素酸化物
を、炭化水素類等の還元剤を用いることにより窒素に接
触還元又は分解する排ガス浄化法である。Further, the exhaust gas purification method of the present invention uses the catalyst of the present invention to use nitrogen oxides in oxygen-rich exhaust gas such as lean burn gasoline engine and diesel engine exhaust gas and a reducing agent such as hydrocarbons. This is an exhaust gas purification method that catalytically reduces or decomposes into nitrogen.
【００１１】窒素酸化物、一酸化炭素及び炭化水素類を
含む排ガスには、例えば、希薄燃焼ガソリンエンジン、
ディーゼルエンジン等の排ガスのような自動車等より排
出される移動発生源排ガスがあるが、本発明はこれらの
排ガスのみに使用されるものに限らず、ボイラー排ガ
ス、硝酸工場等よりの排ガスのような固定発生源排ガス
にも使用可能である。また、還元剤が排ガス中に不足す
る場合は、触媒層の上流において排ガスに炭化水素類及
び／又はアルコール類のような還元剤を添加することも
できる。Exhaust gases containing nitrogen oxides, carbon monoxide and hydrocarbons include, for example, lean burn gasoline engines,
There are mobile source exhaust gases emitted from automobiles such as exhaust gases of diesel engines, etc., but the present invention is not limited to those used only for these exhaust gases, such as boiler exhaust gases, exhaust gases from nitric acid plants, etc. It can also be used for fixed source exhaust gas. Further, when the reducing agent is insufficient in the exhaust gas, a reducing agent such as hydrocarbons and / or alcohols can be added to the exhaust gas upstream of the catalyst layer.
【００１２】本発明の触媒の主要構成物は、多孔質の触
媒担体と、該担体上に担持された白金、遷移金属及び硫
黄であるが、白金及び遷移金属はその一部又は全部が硫
黄化合物として存在している。然しながら、白金及び遷
移金属はその全部が硫黄化合物であることは必ずしも必
要ではない。The main constituents of the catalyst of the present invention are a porous catalyst carrier and platinum, transition metal and sulfur supported on the carrier. Platinum and transition metal are partially or entirely sulfur compounds. Exists as. However, it is not always necessary for platinum and the transition metal to be all sulfur compounds.
【００１３】本発明に用いられる遷移金属は、Ｔｉ，Ｚ
ｒ、Ｖ，Ｎｂ、Ｃｒ，Ｍｏ、Ｍｎ等のIVＢ，ＶＢ，VI
Ｂ，VII Ｂの各族、Ｆｅ，Ｃｏ，Ｎｉ，Ｒｕ，Ｒｈ，Ｐ
ｄ，Ａｕ等のVIII族、Ｃｕ，Ａｇ，Ｚｎ等のＩＡ，IIＡ
の各族金属からなる群より選ばれた１種以上の金属であ
る。Ｆｅ，Ｃｏ，Ｎｉ，Ｃｕ，Ｗ等を含む場合は、特に
優れた活性を示す。更に硫黄化合物及び白金の量は多い
方が、また、遷移金属の量は１〜１０重量％の範囲にあ
るものが優れた活性を示す。The transition metals used in the present invention are Ti, Z
IVB, VB, VI of r, V, Nb, Cr, Mo, Mn, etc.
B, VII B groups, Fe, Co, Ni, Ru, Rh, P
Group VIII such as d and Au, IA and IIA such as Cu, Ag and Zn
Is one or more metals selected from the group consisting of metals of the respective groups. When Fe, Co, Ni, Cu, W, etc. are contained, particularly excellent activity is exhibited. Further, the larger the amount of the sulfur compound and the platinum, and the larger the amount of the transition metal in the range of 1 to 10% by weight, the better the activity.
【００１４】また、本発明の触媒は、上記の主要構成物
のみによって形成されても良いが、これらの主要構成物
以外に、一般に窒素酸化物の接触還元反応に対し触媒活
性を有すると考えられている多くの金属、例えば、アル
カリ金属、アルカリ土類金属、希土類金属、などの金属
を含有せしめることもできる。Further, the catalyst of the present invention may be formed only by the above-mentioned main constituents, but in addition to these main constituents, it is generally considered to have catalytic activity for the catalytic reduction reaction of nitrogen oxides. Many other metals, such as alkali metals, alkaline earth metals, rare earth metals, and the like, can also be included.
【００１５】本発明の触媒の主要構成物の一方である多
孔質担体としては、一般に白金系触媒に使用されている
シリカ、アルミナ、ゼオライト、β−アルミナ等からな
る触媒担体を使用することができる。As the porous carrier which is one of the main constituents of the catalyst of the present invention, a catalyst carrier composed of silica, alumina, zeolite, β-alumina or the like which is generally used for platinum catalysts can be used. .
【００１６】本発明の触媒の形状としては、ハニカム
状、フォーム状、粒状など、その使用目的に応じた各種
の形状とすることができるが、勿論これらの形状に限ら
れるものではない。The catalyst of the present invention may have various shapes such as a honeycomb shape, a foam shape, and a granular shape according to the purpose of use, but it is not limited to these shapes.
【００１７】本発明の触媒は、好ましくは、白金及び遷
移金属を多孔質担体上に担持した本触媒の前駆体を、硫
化ナトリウムのような無機系の硫化剤水溶液中、或いは
ジメチルサルファイドのような有機系の硫化剤の水溶液
又はエタノール溶液中に含浸させることによって製造す
ることができる。尚、本発明の触媒の調製法は、上記の
方法のみに限られるものではない。The catalyst of the present invention is preferably a precursor of the present catalyst in which platinum and a transition metal are supported on a porous carrier, in an inorganic sulfiding agent aqueous solution such as sodium sulfide, or in the form of dimethyl sulfide. It can be produced by impregnation with an aqueous solution of an organic sulfurizing agent or an ethanol solution. The method for preparing the catalyst of the present invention is not limited to the above method.
【００１８】[0018]
【実施例】以下、本発明を実施例に基づいて更に詳細に
説明するが、本発明がこれらのみに限定されるものでは
ない。The present invention will be described in more detail based on the following examples, but the invention is not intended to be limited thereto.
【００１９】実施例１ 米国ビスタケミカル社製 CATAPAL B（商品名）及びラロ
ッシュ製 VERSAL ALUMINA （両者ともベーマイトアルミ
ナ）を酢酸及び純水を用いて解膠させたゲル状物質を直
径約１ｍｍ程度に押出し成型した後、８００℃で焼成処
理したアルミナ担体に、硝酸第二鉄（Ｆｅ（ＮＯ3 ）3
・９Ｈ2 Ｏ）水溶液を所定量の鉄量（２重量％）になる
ように含浸させた後、４００℃で乾燥し、８００℃で５
時間焼成し、更にこれに塩化白金酸（Ｈ2 ＰｔＣｌ6 ）
水溶液を所定の白金量（１０重量％）となるように含浸
させた後、２００℃で乾燥させ、ＰｔＦｅ／Ａｌ2 Ｏ3
触媒を調製した。その後、硫化ナトリウム（Ｎａ2 Ｓ・
９Ｈ2 Ｏ）水溶液をＰｔＦｅ／Ａｌ2 Ｏ3触媒に約１時
間含浸させ、その後純水を用いて約１時間洗浄を行った
後、３００℃で乾燥させ硫化処理した。最後に８００℃
で５時間焼成を行った後評価サンプルとした。Example 1 A gel-like substance obtained by peptizing CATAPAL B (trade name) manufactured by Vista Chemical Co., USA and VERSAL ALUMINA (both boehmite alumina) manufactured by La Roche with acetic acid and pure water is extruded to a diameter of about 1 mm. After molding, ferric nitrate (Fe (NO 3 ) 3
・ 9H 2 O) aqueous solution was impregnated to a predetermined amount of iron (2% by weight), dried at 400 ° C., and then dried at 800 ° C.
Baking for a time, and then chloroplatinic acid (H 2 PtCl 6 )
The solution was impregnated with a predetermined amount of platinum (10% by weight) and dried at 200 ° C. to obtain PtFe / Al 2 O 3
A catalyst was prepared. After that, sodium sulfide (Na 2 S.
The 9H 2 O) aqueous solution was impregnated into the PtFe / Al 2 O 3 catalyst for about 1 hour, followed by washing with pure water for about 1 hour, followed by drying at 300 ° C. and sulfurization treatment. Finally 800 ℃
After firing for 5 hours, it was used as an evaluation sample.
【００２０】実施例２ 鉄量を３重量％になるように含浸させた以外は、実施例
１と同様にして評価サンプルを調製した。Example 2 An evaluation sample was prepared in the same manner as in Example 1 except that the amount of iron was impregnated to 3% by weight.
【００２１】実施例３ 鉄量を７重量％になるように含浸させた以外は、実施例
１と同様にして評価サンプルを調製した。Example 3 An evaluation sample was prepared in the same manner as in Example 1 except that the amount of iron was impregnated to 7% by weight.
【００２２】実施例４ 鉄の代わりにコバルトを用い、コバルト量を３重量％に
なるように硝酸コバルト（Ｃｏ（ＮＯ3 ）2 ・６Ｈ2
Ｏ）水溶液を含浸させた以外は、実施例１と同様にして
評価サンプルを調製した。Example 4 Cobalt nitrate (Co (NO 3 ) 2 .6H 2 ) was used so that the cobalt content was 3% by weight, instead of iron.
O) An evaluation sample was prepared in the same manner as in Example 1 except that the aqueous solution was impregnated.
【００２３】実施例５ 鉄の代わりにニッケルを用い、ニッケル量を３重量％に
なるように硝酸ニッケル（Ｎｉ（ＮＯ3 ）2 ・６Ｈ2
Ｏ）水溶液を含浸させた以外は、実施例１と同様にして
評価サンプルを調製した。Example 5 Nickel was used instead of iron, and nickel nitrate (Ni (NO 3 ) 2 .6H 2 was used so that the amount of nickel was 3% by weight.
O) An evaluation sample was prepared in the same manner as in Example 1 except that the aqueous solution was impregnated.
【００２４】実施例６ 鉄の代わりに銅を用い、銅量を３重量％になるように硝
酸銅（Ｃｕ（ＮＯ3 ） 2 ・６Ｈ2 Ｏ）水溶液を含浸させ
た以外は、実施例１と同様にして評価サンプルを調製し
た。Example 6 Copper was used instead of iron and the amount of copper was adjusted to 3% by weight.
Copper acid (Cu (NO3 ) 2 ・ 6H2 O) impregnated with aqueous solution
An evaluation sample was prepared in the same manner as in Example 1 except that
It was
【００２５】実施例７ 鉄の代わりにタングステンを用い、タングステン量を３
重量％になるようにパラタングステン酸アンモニウム
（（ＮＨ4 ）10Ｗ12Ｏ46Ｈ10・６Ｈ2 Ｏ）水溶液を含浸
させた以外は、実施例１と同様にして評価サンプルを調
製した。Example 7 Tungsten was used instead of iron and the amount of tungsten was 3
An evaluation sample was prepared in the same manner as in Example 1 except that an ammonium paratungstate ((NH 4 ) 10 W 12 O 46 H 10 · 6H 2 O) aqueous solution was impregnated so that the weight% of the sample was obtained.
【００２６】実施例８ 直径２２ｍｍ、長さ５０ｍｍ、１平方インチ（６．４５
ｃｍ2 ）当りのセル数２００ヶのコージエライト製ハニ
カム基体に、実施例１記載のベーマイトアルミナゲル状
物質をウォッシュコートし、次いで８００℃で焼成処理
してアルミナ担体を得た。このアルミナ担体を用いた以
外は、実施例１と同様にして評価サンプルを調製した。Example 8 Diameter 22 mm, length 50 mm, 1 square inch (6.45)
A cordierite honeycomb substrate having 200 cells per cm 2 ) was wash-coated with the boehmite alumina gel-like substance described in Example 1 and then calcined at 800 ° C. to obtain an alumina carrier. An evaluation sample was prepared in the same manner as in Example 1 except that this alumina carrier was used.
【００２７】比較例１ 白金量を１重量％、鉄量を０重量％になるように含浸さ
せた以外は、実施例１と同様にして評価サンプルを調製
した。Comparative Example 1 An evaluation sample was prepared in the same manner as in Example 1 except that the platinum content was 1 wt% and the iron content was 0 wt%.
【００２８】比較例２ 白金量を０重量％、鉄量を３重量％になるように含浸さ
せた以外は、実施例１と同様にして評価サンプルを調製
した。Comparative Example 2 An evaluation sample was prepared in the same manner as in Example 1 except that impregnation was performed so that the amount of platinum was 0% by weight and the amount of iron was 3% by weight.
【００２９】比較例３ 白金量を１０重量％、鉄量０重量％になるように含浸さ
せた以外は、実施例１と同様にして評価サンプルを調製
した。Comparative Example 3 An evaluation sample was prepared in the same manner as in Example 1 except that impregnation was performed so that the amount of platinum was 10% by weight and the amount of iron was 0% by weight.
【００３０】（性能評価）上記の各触媒（評価サンプ
ル）について、下記のように性能評価の活性試験を行っ
た。先ず、上記触媒を内径２３ｍｍの石英管に３ｇ充填
する。この触媒層に、ＮＯ，プロピレン，酸素，水蒸
気，窒素を含有するガス（表１）を６０００ｍｌ／ｍｉ
ｎの割合で導入した。ＮＯは、化学発光式ＮＯx メータ
ーにより分析した。プロピレンは、ＴＣＤガスクロマト
グラフ法により分析した。(Performance Evaluation) With respect to each of the above catalysts (evaluation samples), an activity test for performance evaluation was conducted as follows. First, 3 g of the above catalyst is filled in a quartz tube having an inner diameter of 23 mm. A gas containing NO, propylene, oxygen, water vapor, and nitrogen (Table 1) was added to this catalyst layer at 6000 ml / mi.
It was introduced at a ratio of n. NO was analyzed by chemiluminescence NO x meter. Propylene was analyzed by TCD gas chromatography.
【００３１】[0031]
【表１】 出口ガス濃度の分析により、ＮＯ及びプロピレンの浄化
率を求めた。浄化率は次の式から求めた。[Table 1] The purification rates of NO and propylene were obtained by analyzing the outlet gas concentration. The purification rate was calculated from the following formula.
【００３２】浄化率＝（入口ガス濃度−出口ガス濃度）
÷入口ガス濃度×１００（％） 以上の性能評価の試験結果を表２に示す。Purification rate = (inlet gas concentration-outlet gas concentration)
÷ Inlet gas concentration × 100 (%) Table 2 shows the test results of the above performance evaluation.
【００３３】[0033]
【表２】 表２の試験結果から明らかなように、無機又は有機硫黄
化合物により処理した白金−遷移金属触媒は、同様の処
理をした白金触媒に比較して、より高いＮＯx浄化性能
を示すことが判る。[Table 2] As is clear from the test results in Table 2, the platinum-transition metal catalyst treated with the inorganic or organic sulfur compound exhibits higher NO x purification performance than the platinum catalyst treated in the same manner.
【００３４】[0034]
【発明の効果】上記のように、遷移金属を含有しない従
来型の白金触媒は、硫化処理を行なったものであって
も、本発明の触媒のような優れたＮＯx 浄化性能を発揮
することはできない。この硫化処理白金触媒のＮＯx 浄
化性能の向上策として、白金担持量を増加せしめる方法
を用いることもできるが、本発明の触媒が少量の白金担
持量で優れた浄化性能を発揮することから、高価な白金
の担持量を可及的少量に抑制した上での改良策として、
硫化した遷移金属を併用する本発明の触媒は、経済的効
果をも含めて極めて有効な効果を奏する。As described above, the conventional platinum catalyst containing no transition metal exhibits excellent NO x purification performance like the catalyst of the present invention even if it is subjected to sulfurization treatment. I can't. As a measure for improving the NO x purification performance of this sulfurization-treated platinum catalyst, a method of increasing the platinum loading can be used, but since the catalyst of the present invention exhibits excellent purification performance with a small platinum loading, As an improvement measure after suppressing the amount of expensive platinum supported as much as possible,
The catalyst of the present invention in which a sulfided transition metal is used in combination exhibits extremely effective effects including economic effects.
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.6 識別記号 庁内整理番号 ＦＩ 技術表示箇所 Ｂ０１Ｊ 23/64 ＺＡＢ 8017−4Ｇ 23/652 23/89 ＺＡＢ Ａ 8017−4Ｇ Ｂ０１Ｄ 53/36 １０４ Ａ 8017−4Ｇ Ｂ０１Ｊ 23/64 １０３ Ａ (72)発明者 中野 利彦 山口県下関市彦島迫町７丁目２番10号 東 洋シーシーアイ株式会社下関工場内 (72)発明者 最上 龍一 東京都港区赤坂１丁目９番13号 東洋シー シーアイ株式会社内 (72)発明者 増田 剛司 神奈川県横浜市神奈川区宝町２番地 日産 自動車株式会社内 (72)発明者 大戸 亀久美 神奈川県横浜市神奈川区宝町２番地 日産 自動車株式会社内 (72)発明者 可知 直樹 神奈川県横浜市神奈川区宝町２番地 日産 自動車株式会社内 (72)発明者 室伏 康行 神奈川県横浜市神奈川区宝町２番地 日産 自動車株式会社内─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. 6 Identification code Internal reference number FI Technical display location B01J 23/64 ZAB 8017-4G 23/652 23/89 ZAB A 8017-4G B01D 53/36 104 A 8017-4G B01J 23/64 103 A (72) Inventor Toshihiko Nakano 7-2-10 Hikoshimasako-cho, Shimonoseki-shi, Yamaguchi Toyo CCI Co., Ltd. Shimonoseki factory (72) Inventor Ryuichi Mogami 1 Akasaka, Minato-ku, Tokyo Chome 9-13 Toyo CSI Co., Ltd. (72) Inventor Goji Masuda 2 Takara-cho, Kanagawa-ku, Yokohama, Kanagawa Nissan Motor Co., Ltd. (72) Kamehumi Oto 2 Takara-cho, Kanagawa-ku, Yokohama, Kanagawa Nissan Automobile Co., Ltd. (72) Inventor Naoki Kachi 2 Takara-cho, Kanagawa-ku, Yokohama-shi, Kanagawa Nissan Motor Co., Ltd. (72) Mitsuo Yasuyuki Murofushi Nissan Motor Co., Ltd. 2 Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa
Claims (6)
を含む酸素過剰の排ガスから窒素酸化物、一酸化炭素及
び炭化水素類を除去するための白金及び一種以上の遷移
金属を主成分とする排ガス浄化触媒において、該白金及
び遷移金属が硫黄と多孔質担体上に共存してなることを
特徴とする排ガス浄化触媒。1. A main component is platinum and one or more transition metals for removing nitrogen oxides, carbon monoxide and hydrocarbons from exhaust gas in excess of oxygen containing nitrogen oxides, carbon monoxide and hydrocarbons. The exhaust gas purifying catalyst according to claim 1, wherein the platinum and the transition metal coexist on the porous carrier with sulfur.
と多孔質担体上に共存してなる触媒の、該白金及び一種
以上の遷移金属が、多孔質担体上へ担持された後、硫黄
又は硫黄化合物を加えて硫化処理されてなることを特徴
とする、請求項１記載の排ガス浄化触媒。2. A catalyst comprising platinum and one or more transition metals coexisting with sulfur on a porous carrier. After the platinum and one or more transition metals are supported on the porous carrier, sulfur or The exhaust gas purifying catalyst according to claim 1, wherein the catalyst is sulfurized by adding a sulfur compound.
を含む酸素過剰の排ガスから窒素酸化物、一酸化炭素及
び炭化水素類を除去するための白金及び一種以上の遷移
金属を主成分とする触媒を用いて該排ガスを浄化する方
法において、該触媒が、請求項１又は２に記載の排ガス
浄化触媒であることを特徴とする、排ガス浄化法。3. Platinum and one or more transition metals as main components for removing nitrogen oxides, carbon monoxide and hydrocarbons from oxygen-excess exhaust gas containing nitrogen oxides, carbon monoxide and hydrocarbons. A method for purifying the exhaust gas using the catalyst, wherein the catalyst is the exhaust gas purifying catalyst according to claim 1 or 2.
を、還元剤を用いて接触還元処理することを特徴とす
る、請求項３記載の排ガス浄化法。4. The exhaust gas purification method according to claim 3, wherein the nitrogen oxides in the exhaust gas in excess of oxygen are subjected to catalytic reduction treatment using a reducing agent.
／又はアルコール類であることを特徴とする、請求項４
記載の排ガス浄化法。5. The reducing agent is mainly hydrocarbons and / or alcohols.
Exhaust gas purification method described.
ン又はディーゼルエンジンよりの排ガスであることを特
徴とする、請求項３乃至５の何れかに記載の排ガス浄化
法。6. The exhaust gas purification method according to claim 3, wherein the exhaust gas is an exhaust gas from a lean-burn gasoline engine or a diesel engine.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5188455A JPH0739758A (en) | 1993-07-29 | 1993-07-29 | Catalyst for cleaning exhaust and cleaning method with the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5188455A JPH0739758A (en) | 1993-07-29 | 1993-07-29 | Catalyst for cleaning exhaust and cleaning method with the same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0739758A true JPH0739758A (en) | 1995-02-10 |
Family
ID=16224009
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5188455A Pending JPH0739758A (en) | 1993-07-29 | 1993-07-29 | Catalyst for cleaning exhaust and cleaning method with the same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0739758A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6213828B1 (en) | 1998-06-03 | 2001-04-10 | Kawasaki Jukosyo Kabushiki Kaisha | Exhaust pipe of personal watercraft and connecting structure thereof |
-
1993
- 1993-07-29 JP JP5188455A patent/JPH0739758A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6213828B1 (en) | 1998-06-03 | 2001-04-10 | Kawasaki Jukosyo Kabushiki Kaisha | Exhaust pipe of personal watercraft and connecting structure thereof |
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