JPH09220468A - Catalyst for removal of nox in exhaust gas, its production and method for removing nox in exhaust gas using same - Google Patents
Catalyst for removal of nox in exhaust gas, its production and method for removing nox in exhaust gas using sameInfo
- Publication number
- JPH09220468A JPH09220468A JP8030807A JP3080796A JPH09220468A JP H09220468 A JPH09220468 A JP H09220468A JP 8030807 A JP8030807 A JP 8030807A JP 3080796 A JP3080796 A JP 3080796A JP H09220468 A JPH09220468 A JP H09220468A
- Authority
- JP
- Japan
- Prior art keywords
- catalyst
- oxide
- exhaust gas
- titanium oxide
- nitrogen oxides
- 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 192
- 238000000034 method Methods 0.000 title claims description 23
- 238000004519 manufacturing process Methods 0.000 title claims description 22
- 229910052720 vanadium Inorganic materials 0.000 claims abstract description 26
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 claims abstract description 26
- 229910052710 silicon Inorganic materials 0.000 claims abstract 2
- 239000010703 silicon Substances 0.000 claims abstract 2
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 claims description 105
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims description 49
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 claims description 45
- 239000007789 gas Substances 0.000 claims description 41
- 239000000463 material Substances 0.000 claims description 25
- 229910000476 molybdenum oxide Inorganic materials 0.000 claims description 24
- PQQKPALAQIIWST-UHFFFAOYSA-N oxomolybdenum Chemical compound [Mo]=O PQQKPALAQIIWST-UHFFFAOYSA-N 0.000 claims description 24
- QGLKJKCYBOYXKC-UHFFFAOYSA-N nonaoxidotritungsten Chemical compound O=[W]1(=O)O[W](=O)(=O)O[W](=O)(=O)O1 QGLKJKCYBOYXKC-UHFFFAOYSA-N 0.000 claims description 22
- 229910001930 tungsten oxide Inorganic materials 0.000 claims description 22
- 239000002002 slurry Substances 0.000 claims description 18
- 239000000843 powder Substances 0.000 claims description 14
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 12
- XHCLAFWTIXFWPH-UHFFFAOYSA-N [O-2].[O-2].[O-2].[O-2].[O-2].[V+5].[V+5] Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[V+5].[V+5] XHCLAFWTIXFWPH-UHFFFAOYSA-N 0.000 claims description 10
- 229910001935 vanadium oxide Inorganic materials 0.000 claims description 10
- 239000012784 inorganic fiber Substances 0.000 claims description 8
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 6
- 229910021529 ammonia Inorganic materials 0.000 claims description 6
- 239000011248 coating agent Substances 0.000 claims description 6
- 238000000576 coating method Methods 0.000 claims description 6
- RAHZWNYVWXNFOC-UHFFFAOYSA-N Sulphur dioxide Chemical compound O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 claims description 4
- 238000001035 drying Methods 0.000 claims description 4
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 3
- 238000010304 firing Methods 0.000 claims description 3
- 229910052814 silicon oxide Inorganic materials 0.000 claims description 3
- 229910001873 dinitrogen Inorganic materials 0.000 claims description 2
- 229910052757 nitrogen Inorganic materials 0.000 claims description 2
- -1 Alternatively Chemical compound 0.000 claims 1
- 230000010718 Oxidation Activity Effects 0.000 abstract description 8
- 229910052750 molybdenum Inorganic materials 0.000 abstract description 8
- 229910052721 tungsten Inorganic materials 0.000 abstract description 8
- 239000000758 substrate Substances 0.000 abstract description 7
- 229910052719 titanium Inorganic materials 0.000 abstract description 7
- 239000010936 titanium Substances 0.000 abstract description 7
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 abstract description 6
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 abstract description 6
- 239000011733 molybdenum Substances 0.000 abstract description 6
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 abstract description 6
- 239000010937 tungsten Substances 0.000 abstract description 6
- 238000007254 oxidation reaction Methods 0.000 description 15
- 230000000694 effects Effects 0.000 description 14
- 230000003647 oxidation Effects 0.000 description 14
- 239000010410 layer Substances 0.000 description 13
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 12
- 230000000052 comparative effect Effects 0.000 description 7
- APUPEJJSWDHEBO-UHFFFAOYSA-P ammonium molybdate Chemical compound [NH4+].[NH4+].[O-][Mo]([O-])(=O)=O APUPEJJSWDHEBO-UHFFFAOYSA-P 0.000 description 6
- 229940010552 ammonium molybdate Drugs 0.000 description 6
- 235000018660 ammonium molybdate Nutrition 0.000 description 6
- 239000011609 ammonium molybdate Substances 0.000 description 6
- 239000000203 mixture Substances 0.000 description 4
- 239000002344 surface layer Substances 0.000 description 4
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 3
- 229910010413 TiO 2 Inorganic materials 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 238000004898 kneading Methods 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- UNTBPXHCXVWYOI-UHFFFAOYSA-O azanium;oxido(dioxo)vanadium Chemical compound [NH4+].[O-][V](=O)=O UNTBPXHCXVWYOI-UHFFFAOYSA-O 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 239000011247 coating layer Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 238000000465 moulding Methods 0.000 description 2
- 230000001590 oxidative effect Effects 0.000 description 2
- 238000000746 purification Methods 0.000 description 2
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 description 2
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- 238000003916 acid precipitation Methods 0.000 description 1
- 239000004480 active ingredient Substances 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 238000010531 catalytic reduction reaction Methods 0.000 description 1
- 210000002421 cell wall Anatomy 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000003638 chemical reducing agent Substances 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
- 238000006477 desulfuration reaction Methods 0.000 description 1
- 230000023556 desulfurization Effects 0.000 description 1
- 239000002612 dispersion medium Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000003365 glass fiber Substances 0.000 description 1
- 238000005470 impregnation Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000011068 loading method Methods 0.000 description 1
- 239000002609 medium Substances 0.000 description 1
- 235000006408 oxalic acid Nutrition 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 238000006722 reduction reaction Methods 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 239000011949 solid catalyst Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000002345 surface coating layer Substances 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
Landscapes
- Exhaust Gas Treatment By Means Of Catalyst (AREA)
- Catalysts (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、排ガス中の窒素酸
化物除去用触媒、その製造方法およびこれを用いた排ガ
ス中の窒素酸化物除去方法に係り、特に排ガス中のＳＯ
2 をＳＯ3 に酸化する活性を抑制した高活性な窒素酸化
物除去用触媒、その製造方法およびそれら触媒を使った
排ガス浄化方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catalyst for removing nitrogen oxides in exhaust gas, a method for producing the same, and a method for removing nitrogen oxides in exhaust gas using the same, particularly SO in exhaust gas.
The present invention relates to a highly active catalyst for removing nitrogen oxides which suppresses the activity of oxidizing 2 into SO 3 , a method for producing the same, and an exhaust gas purification method using the catalyst.
【０００２】[0002]
【従来の技術】発電所、各種工場、自動車などから排出
される排ガス中のＮＯｘは、光化学スモッグや酸性雨の
原因物質であり、その効果的な除去方法として、アンモ
ニア（ＮＨ3 ）を還元剤とした選択的接触還元による排
ガス脱硝法が、火力発電所を中心に幅広く用いられてい
る。触媒には、バナジウム（Ｖ）、モリブデン（Ｍｏ）
またはタングステン（Ｗ）を活性成分にした酸化チタン
（ＴｉＯ2 ）系触媒が使用されており、特に活性成分の
１つとしてバナジウムを含むものは活性が高いだけでな
く、排ガス中に含まれている不純物による劣化が小さい
こと、より低温から使用できることなどから、現在の脱
硝触媒の主流になっている（特開昭５０−１２８６８１
号公報等）。その製造法にはあらかじめ酸化チタン原料
とＷ、Ｍｏ、Ｖ原料とを混練して得たペーストを、また
は必要に応じてこれをさらに焼成・粉砕した後、水とと
もに混練してペースト状にしたものをハニカム状に押出
成形する方法や、金属またはセラミックス製基板に塗布
して板状触媒にする方法が広く用いられてきた（特公昭
６０−３８５６号公報、特公昭６１−２８３７７号公
報）。2. Description of the Related Art NOx in exhaust gas emitted from power plants, various factories, automobiles, etc. is a causative substance of photochemical smog and acid rain, and ammonia (NH 3 ) is used as a reducing agent as an effective removal method. The exhaust gas denitration method by selective catalytic reduction is widely used mainly in thermal power plants. The catalyst is vanadium (V), molybdenum (Mo)
Alternatively, a titanium oxide (TiO 2 ) -based catalyst containing tungsten (W) as an active component is used. Particularly, one containing vanadium as one of the active components is not only highly active, but also contained in exhaust gas. Since it is less deteriorated by impurities and can be used at lower temperatures, it has become the mainstream of the present denitration catalyst (Japanese Patent Laid-Open No. 50-128681).
No.). In the production method, a paste obtained by previously kneading the titanium oxide raw material and the W, Mo, V raw material, or if necessary, further calcined and crushed, and then kneaded with water to form a paste The method of extruding a honeycomb structure into a honeycomb shape or the method of applying it to a metal or ceramic substrate to form a plate catalyst has been widely used (Japanese Patent Publication No. 60-3856 and Japanese Patent Publication No. 61-28377).
【０００３】[0003]
【発明が解決しようとする課題】上記従来触媒は、前述
したようにあらかじめ触媒成分を調製し、これをハニカ
ム状や板状に成形するため次のような多くの問題を有し
ている。第１は、触媒成分自体を成形して形状を保持さ
せるため、実用的な強度を維持しようとするとハニカム
触媒のセル壁、または板状触媒の厚みを小さくすること
が不可能である。このため近年の省資源、省エネルギー
の時流に対応することが難しくなっている。The above-mentioned conventional catalyst has many problems as described below because the catalyst components are prepared in advance and formed into a honeycomb shape or a plate shape as described above. First, since the catalyst component itself is molded to maintain its shape, it is impossible to reduce the thickness of the cell wall of the honeycomb catalyst or the thickness of the plate-shaped catalyst in order to maintain practical strength. Therefore, it is difficult to cope with the recent trend of resource saving and energy saving.
【０００４】第２の問題は、第１の問題とも関連する
が、触媒成分の使用量を一定以下に下げられないため、
排ガスの浄化に使用した場合、排ガス中に含まれるＳＯ
2 がＳＯ3 に酸化する副反応を一定以下にできない。Ｓ
Ｏ3 はＳＯ2 に較べ大気に放出された場合の毒性が高い
上、脱硫装置で除去されにくいため、上記ＳＯ2 の酸化
活性が高い点は改善されるべき大きな課題である。The second problem is related to the first problem, but since the amount of the catalyst component used cannot be reduced below a certain level,
When used for purification of exhaust gas, SO contained in exhaust gas
The side reaction that 2 oxidizes to SO 3 cannot be kept below a certain level. S
O 3 is more toxic than SO 2 when it is released into the atmosphere, and is difficult to be removed by a desulfurization device. Therefore, the high oxidizing activity of SO 2 is a major issue to be improved.
【０００５】さらに第３の問題として、近年事業用ボイ
ラなどの排ガスではＮＯｘの排出量を現在のレベルより
低下するために大量の脱硝触媒を使用することが多くな
る傾向にある。このような装置に従来技術の触媒を適用
すると一層ＳＯ2 の酸化割合が著しく高くなり、環境面
だけでなく脱硝装置後流機器にも悪影響を引き起こす。Further, as a third problem, in recent years, a large amount of NOx removal catalyst tends to be used in order to reduce the NOx emission amount from the present level in exhaust gas from commercial boilers and the like. If the catalyst of the prior art is applied to such an apparatus, the oxidation rate of SO 2 will be remarkably increased, which will adversely affect not only the environment but also the downstream equipment of the denitration apparatus.
【０００６】上記したように触媒成分をハニカム／板状
に成形して用いる触媒では、触媒原料使用量を一定以上
低下しにくいだけでなく、脱硝活性を維持しようとする
とＳＯ2 酸化活性を低く抑えることが難しいという問題
があった。本発明の目的は、上記した従来触媒の問題点
をなくし、高い脱硝活性と低いＳＯ2 酸化活性を両立さ
せた触媒と、この触媒を得るための経済的に優れた触媒
製造方法と、この触媒を用いた排ガス中の窒素酸化物除
去方法を提供することにある。[0006] As described above, in the case where the catalyst is used by forming the catalyst component into a honeycomb / plate shape, not only is it difficult to reduce the amount of the catalyst raw material used above a certain amount, but also the SO 2 oxidation activity is suppressed to a low level in order to maintain the denitration activity. There was a problem that it was difficult. The object of the present invention is to eliminate the above-mentioned problems of conventional catalysts, a catalyst that achieves both high denitration activity and low SO 2 oxidation activity, an economically excellent catalyst production method for obtaining this catalyst, and this catalyst. It is to provide a method for removing nitrogen oxides in exhaust gas using
【０００７】[0007]
【課題を解決するための手段】上記目的を達成するため
本願で特許請求される発明は以下のとおりである。 （１）酸化チタン、酸化モリブデンおよび／または酸化
タングステン、ならびに酸化バナジウムを活性成分とす
る窒素酸化物除去用触媒において、該触媒が成形体触媒
であり、該触媒成形体の表面部のバナジウム含有量が内
部のそれより高いことを特徴とする排ガス中の窒素酸化
物除去用触媒。The invention claimed in the present application to achieve the above object is as follows. (1) In a catalyst for removing nitrogen oxides containing titanium oxide, molybdenum oxide and / or tungsten oxide, and vanadium oxide as active ingredients, the catalyst is a molded catalyst, and the vanadium content of the surface portion of the molded catalyst is Is higher than that of the inside, the catalyst for removing nitrogen oxides in exhaust gas.
【０００８】（２）（１）記載の触媒において、表面部
の高バナジウム含有量層がコーティングにより形成され
た酸化チタン、酸化モリブデンおよび／または酸化タン
グステン、ならびに酸化バナジウムとからなる触媒成分
層であることを特徴とする排ガス中の窒素酸化物除去用
触媒。 （３）（１）〜（２）記載の触媒において、触媒表面の
高バナジウム含有触媒層が厚み０．１mm以下で、かつ単
位面積当たりのコーティング量が１００ｇ／ｍ 2 以下で
あることを特徴とする排ガス中の窒素酸化物除去用触
媒。(2) In the catalyst described in (1), the surface portion
A high vanadium content layer of
Titanium oxide, molybdenum oxide and / or tan oxide
Catalyst component consisting of gustene and vanadium oxide
For removing nitrogen oxides in exhaust gas, characterized by being a layer
catalyst. (3) In the catalyst described in (1) to (2),
The high vanadium-containing catalyst layer has a thickness of 0.1 mm or less, and
Coating amount per unit area is 100g / m TwoBelow
A catalyst for removing nitrogen oxides in exhaust gas, characterized by being
Medium.
【０００９】（４）（１）〜（３）記載の触媒におい
て、触媒内部および触媒表面の総バナジウム含有率が
０．５ｗｔ％以下であることを特徴とする排ガス中の窒
素酸化物除去用触媒。 （５）（１）〜（４）記載の触媒において、触媒内部が
酸化チタンと酸化モリブデン、酸化チタンと酸化タング
ステン、または酸化チタンと酸化モリブデンと酸化タン
グステンであることを特徴とする排ガス中の窒素酸化物
除去用触媒。(4) In the catalysts according to (1) to (3), the total vanadium content in the catalyst and on the surface of the catalyst is 0.5 wt% or less, and a catalyst for removing nitrogen oxides in exhaust gas. . (5) In the catalyst according to (1) to (4), nitrogen in exhaust gas, characterized in that the inside of the catalyst is titanium oxide and molybdenum oxide, titanium oxide and tungsten oxide, or titanium oxide, molybdenum oxide and tungsten oxide. Oxide removal catalyst.
【００１０】（６）（１）〜（５）記載の触媒におい
て、触媒基材である網状無機繊維物間および網目間に酸
化チタンと酸化モリブデン、または酸化チタンと酸化タ
ングステン、酸化チタンと酸化モリブデンと酸化タング
ステンを主成分とする酸化物が埋められた状態の板状成
形体表面に高バナジウム含有成分層が形成されたことを
特徴とする排ガス中の窒素酸化物除去用触媒。(6) In the catalysts according to (1) to (5), titanium oxide and molybdenum oxide, titanium oxide and tungsten oxide, titanium oxide and molybdenum oxide are present between the reticulated inorganic fiber materials which are the catalyst base material and between the reticulated inorganic fiber materials. A catalyst for removing nitrogen oxides in exhaust gas, wherein a high vanadium-containing component layer is formed on the surface of a plate-shaped compact filled with an oxide containing tungsten oxide as a main component.
【００１１】（７）酸化チタン、酸化モリブデンまたは
酸化タングステン、および酸化バナジウムとを活性成分
とする窒素酸化物除去用触媒の製造方法において、酸化
チタンと酸化モリブデン、酸化チタンと酸化タングステ
ン、または酸化チタンと酸化ケイ素を主成分とする触媒
基材成形体を形成し、これを乾燥、焼成したのち、この
表面に高バナジウム含有触媒成分のスラリを塗布するこ
とを特徴とする排ガス中の窒素酸化物除去用触媒の製造
方法。(7) In a method for producing a catalyst for removing nitrogen oxides containing titanium oxide, molybdenum oxide or tungsten oxide, and vanadium oxide as active components, titanium oxide and molybdenum oxide, titanium oxide and tungsten oxide, or titanium oxide. Nitrogen oxide removal in exhaust gas, characterized in that a catalyst base material molded body containing silicon oxide as a main component is formed, dried and fired, and then a slurry of a catalyst component having a high vanadium content is applied to the surface thereof. For producing catalyst for automobile.
【００１２】（８）酸化チタン、酸化モリブデンまたは
酸化タングステン、および酸化バナジウムを活性成分と
する窒素酸化物除去用触媒の製造方法において、酸化チ
タンと酸化モリブデン、酸化チタンと酸化タングステ
ン、または酸化チタンと酸化ケイ素を主成分とする湿式
触媒基材成形体を形成し、この湿式成形体に高バナジウ
ム含有触媒成分を担持させたのち、乾燥、焼成すること
を特徴とする排ガス中の窒素酸化物除去用触媒の製造方
法。(8) In the method for producing a catalyst for removing nitrogen oxides containing titanium oxide, molybdenum oxide or tungsten oxide, and vanadium oxide as active components, titanium oxide and molybdenum oxide, titanium oxide and tungsten oxide, or titanium oxide are used. For removing nitrogen oxides in exhaust gas, which is characterized in that a wet catalyst base material molded body containing silicon oxide as a main component is formed, and a catalyst component having a high vanadium content is supported on the wet molded body, followed by drying and firing. Method for producing catalyst.
【００１３】（９）（８）記載の触媒の製造方法におい
て、スラリの担持手段が、スラリを一旦弾性を有するロ
ーラに付着させた後、ローラを前記湿式成形体表面と接
触させて、該成形体表面にスラリを転着することを特徴
とする排ガス中の窒素酸化物除去用触媒の製造方法。 （１０）（８）記載の触媒の製造方法において、湿式成
形体への高バナジウム含有触媒成分の担持方法が、上記
湿式成形体と高バナジウム含有触媒成分粉末とを接触さ
せることにより行われ、これにより該湿式成形体表面に
高バナジウム含有成分層が形成されることを特徴とする
排ガス中の窒素酸化物除去用触媒の製造方法。(9) In the method for producing a catalyst according to (8), the slurry carrying means temporarily attaches the slurry to a roller having elasticity, and then the roller is brought into contact with the surface of the wet compact to form the compact. A method for producing a catalyst for removing nitrogen oxides in exhaust gas, which comprises transferring slurry to a body surface. (10) In the method for producing a catalyst according to (8), the method for supporting the high vanadium-containing catalyst component on the wet compact is carried out by bringing the wet compact into contact with the high vanadium-containing catalyst component powder. Is used to form a high vanadium-containing component layer on the surface of the wet compact, the method for producing a catalyst for removing nitrogen oxides in exhaust gas.
【００１４】（１１）窒素酸化物とともに亜硫酸ガスを
含有する排ガス中の窒素酸化物除去方法において、前記
排ガスをアンモニアの存在下、（１）〜（６）記載の触
媒と接触させて、前記窒素酸化物をアンモニアにより還
元することを特徴とする排ガス中の窒素酸化物除去方
法。(11) In the method for removing nitrogen oxides in exhaust gas containing sulfur dioxide together with nitrogen oxide, the exhaust gas is brought into contact with the catalyst according to (1) to (6) in the presence of ammonia to produce the nitrogen gas. A method for removing nitrogen oxides in exhaust gas, which comprises reducing oxides with ammonia.
【００１５】[0015]
【発明の実施の形態】上記従来技術の問題点は、酸化チ
タン（ＴｉＯ2 ）、酸化チタンとモリブデン（Ｍｏ）酸
化物、酸化チタンとタングステン（Ｗ）酸化物、または
これらの酸化物とバナジウム（Ｖ）酸化物を主成分とす
る成形体表面に、Ｖ含有量の高い触媒成分層を形成させ
ることによって解決することができる。DESCRIPTION OF THE PREFERRED EMBODIMENTS The problems of the above-mentioned prior art are that titanium oxide (TiO 2 ), titanium oxide and molybdenum (Mo) oxide, titanium oxide and tungsten (W) oxide, or these oxides and vanadium ( V) The problem can be solved by forming a catalyst component layer having a high V content on the surface of a molded body containing an oxide as a main component.
【００１６】すなわち、本発明の窒素酸化物除去用触媒
は、図１に示すように、ＴｉＯ2 、ＴｉＯ2 とＭｏ
Ｏ3 、ＴｉＯ2 とＷＯ3 とからなる成形体内部を構成す
る触媒基材（低Ｖ濃度層）２の表面にチタン、タングス
テンまたはモリブデン、およびバナジウムとからなる触
媒成分層（高Ｖ濃度層）１を形成し、触媒表面のＶ含有
量を内部に較べ大きく高めたことを特徴とするものであ
る。That is, as shown in FIG. 1, the catalyst for removing nitrogen oxides of the present invention comprises TiO 2 , TiO 2 and Mo.
A catalyst component layer (high V concentration layer) composed of titanium, tungsten or molybdenum, and vanadium on the surface of a catalyst base material (low V concentration layer) 2 forming the inside of a molded body made of O 3 , TiO 2 and WO 3. 1 is formed, and the V content on the surface of the catalyst is greatly increased as compared with the inside.
【００１７】ここで基材となる内部触媒層は、通常の方
法により成形されたハニカム状または板状の成形体であ
り、Ｖ含有量が低く抑えられている。また、表面の被覆
層はＶの含有量の高いＴｉ、Ｗ、ＭｏおよびＶとからな
るＶ含有量４〜１２原子％の触媒成分であり、基材とな
るハニカムまたは板状体が成形された後、粉末状または
水を分散媒とするスラリの形で付着させて形成され、そ
の付着量は小さく５〜１００ｇ／ｍ2 であり、厚みは
０．１mm以下と少量である。The internal catalyst layer, which is the base material, is a honeycomb-shaped or plate-shaped molded body molded by a usual method, and has a low V content. Further, the surface coating layer is a catalyst component having a V content of 4 to 12 atom%, which is composed of Ti, W, Mo, and V having a high V content, and a honeycomb or plate-like body as a base material was formed. After that, it is formed by adhering in the form of powder or slurry with water as a dispersion medium, the adhering amount is small and 5 to 100 g / m 2 , and the thickness is 0.1 mm or less and a small amount.
【００１８】被覆量は、具体的にはハニカムまたは板状
の湿式成形体がまだ湿った状態の時点で、上記高Ｖ触媒
成分粉末と接することにより付着させるか、成形後湿っ
た状態もしくは一旦焼成したものに触媒スラリを塗布、
または転着することにより形成することができる。この
ようにして得られた触媒の全体としてのＶ含有量は、用
いる排ガスの種類による異なるが、ＳＯ2 酸化が問題と
なる場合には０．５ｗｔ％以下、望ましくは０．２ｗｔ
％以下が好結果を与える。また、ＳＯ2 を含まずＳＯ2
酸化の問題にならない排ガスでは制限はないが、この場
合であっても１ｗｔ％以下で充分な性能が得られる。Specifically, the coating amount is such that when the honeycomb or plate-like wet compact is still in a wet state, it is adhered by contact with the above-mentioned high V catalyst component powder, or it is in a wet state after molding or once fired. Apply catalyst slurry to the
Alternatively, it can be formed by transferring. The total V content of the catalyst thus obtained varies depending on the type of exhaust gas used, but when SO 2 oxidation is a problem, it is 0.5 wt% or less, preferably 0.2 wt%.
% Or less gives good results. Also, SO 2 free of SO 2
There is no limitation with exhaust gas that does not cause a problem of oxidation, but even in this case, sufficient performance can be obtained at 1 wt% or less.
【００１９】図２は、従来触媒について反応時における
ＮＯｘとＳＯ2 濃度の表面から内部への分布を示したも
のである。この図から明らかなように、ＮＯｘのアンモ
ニアによる還元反応は速いので、触媒表面部で大半が反
応してＮＯｘが消失してしまうために、触媒内部はほと
んど利用されない。これに対し、ＳＯ2 の酸化反応は遅
いため触媒表面から内部までＳＯ2 の濃度が変わらず、
触媒内部も表面と同等にＳＯ2 の酸化促進に寄与する。
このため従来触媒のように表面から内部までが同一組成
である触媒では、脱硝活性を高めるため活性成分である
Ｖ含有量を増大すると、脱硝活性の増大に較べ触媒内部
におけるＳＯ2 酸化活性が著しく増大するという問題を
生じる。これはＶが脱硝活性成分であると同時にＳＯ2
酸化活性成分でもあることに加え、触媒内部では図２の
ような濃度分布であることが大きな原因となっている。
この点が従来触媒の限界であり、解決すべき問題でもあ
った。FIG. 2 shows the distribution of NOx and SO 2 concentrations from the surface to the inside of the conventional catalyst during the reaction. As is clear from this figure, since the reduction reaction of NOx with ammonia is fast, most of the catalyst reacts on the surface of the catalyst and NOx disappears, so the inside of the catalyst is hardly used. On the other hand, since the SO 2 oxidation reaction is slow, the SO 2 concentration does not change from the catalyst surface to the inside,
The inside of the catalyst also contributes to the promotion of SO 2 oxidation similarly to the surface.
Therefore, in the case of a catalyst having the same composition from the surface to the inside, such as a conventional catalyst, when the V content, which is an active component, is increased in order to enhance the denitration activity, the SO 2 oxidation activity inside the catalyst remarkably increases as compared with the increase in the denitration activity. Creates the problem of increasing. This is because V is a denitration active component and at the same time SO 2
In addition to being an oxidatively active component, the concentration distribution as shown in FIG. 2 inside the catalyst is a major cause.
This point is the limit of the conventional catalyst, and it has been a problem to be solved.
【００２０】これに対し、図１に示した本発明では必要
なＶの大半を触媒表面層に集中させたことにより、 （１）ＮＯｘ濃度の高い表層部で効率よく脱硝反応が進
行するため、触媒全体としての活性が向上する。 （２）ＳＯ2 の酸化の大半を担う触媒内部のＶ含有量を
非常に小さくできるためＳＯ2 酸化活性が低い触媒にな
る。など、従来技術の課題を解消することができる。On the other hand, in the present invention shown in FIG. 1, by concentrating most of the required V in the catalyst surface layer, (1) the denitration reaction proceeds efficiently in the surface layer portion having a high NOx concentration. The activity of the catalyst as a whole is improved. (2) SO 2 oxidation activity for the V content of the internal catalyst can be made very small responsible for most of the oxidation of SO 2 is low catalyst. Thus, the problems of the conventional technology can be solved.
【００２１】さらに、（３）触媒内部の活性は触媒活性
が低くてもよいため、強度に優れる組成とすることによ
り触媒厚みを小さくし易いだけでなく、薄肉の触媒を調
製することができる。この結果、非常に少ない触媒成分
量で脱硝活性は従来触媒と同等でＳＯ2 酸化活性の小さ
い触媒が実現でき、大量に触媒を用いて高脱硝率を得よ
うとする脱硝装置のＳＯ2 酸化によるＳＯ3 副生を飛躍
的に低下せしめることが可能になる。Further, (3) since the activity inside the catalyst may be low, the catalyst thickness can be easily reduced by preparing a composition having excellent strength, and a thin catalyst can be prepared. By this result, very little solid catalyst component per denitration activity can be realized conventional catalyst and a small catalyst of SO 2 oxidation activity equivalent, large quantities SO 2 oxidation denitrification device to be obtained with high denitrification rate by using a catalyst It is possible to dramatically reduce SO 3 by -product.
【００２２】これに加えて、本発明の触媒に必要な触媒
量は前述したように触媒重量で５〜１００ｇ／ｍ2 、被
覆層は０．１mm以下であるため、湿式成形の後、成形体
の持つ水分で触媒粉を表面に付着させるなどの従来の触
媒製造法の補助手段程度の設備で達成できることも大き
な特徴である。以下、具体例を用いて本発明を詳細に説
明する。In addition to this, the catalyst amount required for the catalyst of the present invention is 5 to 100 g / m 2 in terms of catalyst weight and the coating layer is 0.1 mm or less as described above. It is also a major feature that it can be achieved with equipment such as an auxiliary means of conventional catalyst production methods, such as attaching catalyst powder to the surface with the water contained therein. Hereinafter, the present invention will be described in detail with reference to specific examples.
【００２３】[0023]
実施例１〜５ 酸化チタン粉末２０kgにモリブデン酸アンモニウム
（（ＮＨ4 ）6 ・Ｍｏ7 Ｏ 24・４Ｈ2 Ｏ）を２．３kg、
無機繊維（商品名カオウール）を３．３kgとに水を加え
てニーダで混練し、水分３２％の基材用ペーストを調製
した。 Examples 1 to 5 Ammonium molybdate on 20 kg of titanium oxide powder
((NHFour)6・ Mo7O twenty four・ 4HTwoO) 2.3 kg,
3.3kg of inorganic fiber (brand name Kaowool) and water added
And kneading with a kneader to prepare a paste for base material with a water content of 32%
did.
【００２４】一方、繊維径９μｍのＥガラス製繊維１４
００本の捻糸を１０本／インチの粗さで平織りした網状
物にチタニア４０％、シリカゾル２０％、ポリビニルア
ルコール１％のスラリを含浸し、１５０℃で乾燥して剛
性を持たせ触媒基材を得た。本触媒基材２枚の間に上記
基材用ペーストを置き、圧延ローラを通すことにより酸
化チタンと酸化モリブデンとからなる厚み１．２mmの板
状触媒基材を得た。これを１２時間大気中で風乾した
後、５００℃で２時間焼成した。On the other hand, an E-glass fiber 14 having a fiber diameter of 9 μm
A mesh made of plain weave of 00 threads with a roughness of 10 threads / inch is impregnated with a slurry of 40% titania, 20% silica sol and 1% polyvinyl alcohol, and dried at 150 ° C to give rigidity and a catalyst substrate. Got The paste for a base material was placed between two sheets of the catalyst base material and passed through a rolling roller to obtain a plate-like catalyst base material having a thickness of 1.2 mm and made of titanium oxide and molybdenum oxide. This was air-dried for 12 hours in the air and then fired at 500 ° C. for 2 hours.
【００２５】これとは別に、酸化チタン粉末２０kgにモ
リブデン酸アンモニウム（（ＮＨ4）6 ・Ｍｏ7 Ｏ24・
４Ｈ2 Ｏ）を２．５kg、メタバナジン酸アンモニウム
２．３３kg、蓚酸３．０kgとに水を加えてニーダで混練
してペースト状にしたものを３φの柱状に造粒後、流動
層乾燥器で乾燥、５００℃で２時間焼成し、続いてハン
マーミルで粉砕して１μｍ以下、５０％以上の触媒粉末
を得た（Ｖ含有量：３．５６ｗｔ％）。得られた粉末１
００ｇに水を加えてスラリにし、本スラリを刷毛を用い
て上記板状触媒基材表面に触媒成分が１ｍ2 当たり、そ
れぞれ５、１０、３０、５０、１００ｇになるように塗
布した後、１５０℃で乾燥して触媒を得た。Separately from this, 20 kg of titanium oxide powder was added to ammonium molybdate ((NH 4 ) 6 Mo 7 O 24
4H 2 O) 2.5 kg, ammonium metavanadate 2.33 kg, and oxalic acid 3.0 kg, and water was added and kneaded with a kneader to form a paste. Drying, firing at 500 ° C. for 2 hours, and subsequent pulverization with a hammer mill gave a catalyst powder of 1 μm or less and 50% or more (V content: 3.56 wt%). The obtained powder 1
Water was added to 00 g to make a slurry, and the slurry was applied to the surface of the plate-like catalyst base material using a brush so that the catalyst component was 5 , 10, 30, 50, and 100 g per 1 m 2 , respectively. The catalyst was obtained by drying at ℃.
【００２６】本触媒の被覆層の厚みはいずれも０．１mm
以下であり、密度からの計算厚みはそれぞれ約０．０
５、０．０１、０．０３、０．０５、０．１mmに相当す
る。また、触媒中のＶ含有量はそれぞれ０．０１６、
０．０３２、０．０９７、０．１６、０．３２ｗｔ％で
ある。 比較例１ 実施例１〜５における触媒スラリの（刷毛による）塗布
を行わないで、板状触媒基材のみを用いた。 比較例２ 実施例１の塗布に使った触媒中のＶ含有量３．５６ｗｔ
％の触媒２０kgを用い、これに前記無機繊維３kgと水を
加えて混練し、板状触媒基材を得た方法と同様の方法で
網状基材に塗布した触媒を得た。 比較例３〜７ 酸化チタン粉末２０kgにモリブデン酸アンモニウム
（（ＮＨ4 ）6 ・Ｍｏ7 Ｏ 24・４Ｈ2 Ｏ）を２．３kg、
無機繊維（商品名カオウール）を３．３kg、さらにメタ
バナジン酸アンモニウムをそれぞれ３９、７７、２３
４、３８２、７７４ｇ添加した後、水を加えてニーダで
混練し、水分３２％の基材用ペーストを調製した。本ペ
ーストを実施例１〜５に用いた板状触媒基板の調製法と
同様の方法で板状化した後、５００℃で２時間焼成して
触媒を得た。The thickness of the coating layer of this catalyst is 0.1 mm in each case.
The thickness calculated from the density is about 0.0
Equivalent to 5, 0.01, 0.03, 0.05, 0.1 mm
You. The V content in the catalyst is 0.016,
0.032, 0.097, 0.16, 0.32 wt%
is there. Comparative Example 1 Application of catalyst slurry in Examples 1-5 (by brush)
Was not used, and only the plate-shaped catalyst substrate was used. Comparative Example 2 V content in the catalyst used for coating of Example 1 3.56 wt
% Of catalyst is used, to which 3 kg of the inorganic fiber and water are added.
In addition, kneading was carried out in the same manner as the method for obtaining the plate-shaped catalyst substrate.
A catalyst coated on a reticulated substrate was obtained. Comparative Examples 3 to 7 Ammonium molybdate on 20 kg of titanium oxide powder
((NHFour)6・ Mo7O twenty four・ 4HTwoO) 2.3 kg,
3.3 kg of inorganic fiber (trade name Kaowool), and more
Ammonium vanadate is 39, 77, 23 respectively
After adding 4,382,774g, add water and kneader
The mixture was kneaded to prepare a base material paste having a water content of 32%. Book
And a method for preparing a plate-like catalyst substrate using the same as Examples 1 to 5.
After plate-forming by the same method, fire at 500 ° C for 2 hours
A catalyst was obtained.
【００２７】この触媒中のＶ含有量は、それぞれ実施例
１〜５と同じ０．０１６、０．０３２、０．０９７、
０．１６、０．３２ｗｔ％である。 実施例６ 実施例２の基材用ペーストおよび刷毛による塗布用スラ
リの製造に使ったモリブデン酸アンモニウムに変えて、
等モルのパラタングステン酸アンモニウム（（ＮＨ4 ）
10・Ｗ12Ｏ41・５Ｈ2 Ｏ）を用いたほかは同様に触媒を
得た。 実施例７ 実施例２触媒における基材用ペーストに添加したモリブ
デン酸アンモニウムに変え、シリカゾルを同重量用いて
触媒基材を得たほかは、同様の方法で触媒を調製した。The V content in this catalyst was 0.016, 0.032, 0.097, the same as in Examples 1 to 5, respectively.
0.16 and 0.32 wt%. Example 6 In place of the ammonium molybdate used in the production of the base paste and brush-applied slurry of Example 2,
Equimolar ammonium paratungstate ((NH 4 )
10 · W 12 O 41 · 5H 2 O) but using the catalyst was obtained in the same manner. Example 7 A catalyst was prepared in the same manner as in Example 2 except that ammonium molybdate added to the base material paste in the catalyst was replaced with the same weight of silica sol to obtain the catalyst base material.
【００２８】実施例１〜７の触媒と比較例１〜７の触媒
について、表１の条件で脱硝率、表２の条件でＳＯ2 酸
化率を測定し、結果を表３にまとめて示した。また図３
には単位触媒当たりのＶ量をパラメータにとり、従来触
媒（比較例３〜７）と本発明の触媒（実施例１〜５）と
の脱硝率ならびにＳＯ2 酸化率を比較して示した。With respect to the catalysts of Examples 1 to 7 and Comparative Examples 1 to 7, the denitration rate was measured under the conditions of Table 1 and the SO 2 oxidation rate under the conditions of Table 2, and the results are summarized in Table 3. . FIG.
In the table, the amount of V per unit catalyst is taken as a parameter, and the denitrification rate and SO 2 oxidation rate of the conventional catalyst (Comparative Examples 3 to 7) and the catalyst of the present invention (Examples 1 to 5) are shown in comparison.
【００２９】[0029]
【表１】 [Table 1]
【００３０】[0030]
【表２】 [Table 2]
【００３１】[0031]
【表３】 表３において、比較例１および２と実施例１の比較か
ら、本発明の方法は脱硝性能向上に著しい効果がある
上、使用した触媒成分単独のＳＯ2 酸化率に比し飛躍的
にＳＯ2 酸化率を低減できることが分かる。[Table 3] In Table 3, Comparative Examples 1 and 2 and Example Comparison 1, on the method of the present invention have a significant effect on NOx removal performance improvement, compared with the SO 2 oxidation rate of the catalyst components alone using dramatically SO 2 It can be seen that the oxidation rate can be reduced.
【００３２】また、Ｖ含有量を実施例１〜５と同じくし
た比較例３〜７の触媒と較べた図３のように、同一Ｖ含
有量での脱硝率は本発明の触媒が優れていることが分か
る。さらに、本発明の触媒では脱硝率が向上しても、Ｓ
Ｏ2 酸化率はほとんど上昇しないことがわかる。以上に
示したことから、本発明の触媒は高活性と低ＳＯ2 酸化
性とを達成するに好適な触媒であることは明白である。 実施例８ 実施例１で酸化チタンとモリブデン酸アンモニウムのペ
ーストから得た板状触媒基材を、成形直後の触媒がいま
だ乾燥しないうちに、塗布用スラリの調製に用いたＶを
含有する触媒成分粉末を空気流で流動化させた中に入
れ、成形体が含む水分をバインダにして触媒粉末を付着
させた。その表面をローラで押さえて平坦にした後、乾
燥し、続いて５００℃で２時間焼成して触媒を得た。そ
のときの触媒粉末の付着量は約３０ｇ／ｍ2 であった。 実施例９ 実施例１で用いたＶ含有触媒の粉末に同重量の水を加え
て高粘度のスラリを得た。このスラリを一旦ゴムローラ
に薄く添着した後、そのゴムローラを実施例８に用いた
板状触媒基材表面上で回転させ、基材表面に薄い触媒成
分層を形成した。その後、乾燥し、さらに５００℃で２
時間焼成して触媒を得た。Further, as shown in FIG. 3 comparing the catalysts of Comparative Examples 3 to 7 in which the V content was the same as that of Examples 1 to 5, the catalyst of the present invention is superior in the denitration rate at the same V content. I understand. Further, in the catalyst of the present invention, even if the denitration rate is improved, S
It can be seen that the O 2 oxidation rate hardly increases. From the above, it is clear that the catalyst of the present invention is suitable for achieving high activity and low SO 2 oxidizability. Example 8 The catalyst component containing V used in the preparation of the slurry for coating was applied to the plate-shaped catalyst base material obtained from the paste of titanium oxide and ammonium molybdate in Example 1 while the catalyst immediately after molding was not yet dried. The powder was placed in a fluidized form with an air stream, and the catalyst powder was attached by using the water contained in the molded body as a binder. The surface was pressed by a roller to flatten it, dried, and then calcined at 500 ° C. for 2 hours to obtain a catalyst. The amount of the catalyst powder deposited at that time was about 30 g / m 2 . Example 9 The same weight of water was added to the powder of the V-containing catalyst used in Example 1 to obtain a high viscosity slurry. This slurry was once thinly attached to a rubber roller, and then the rubber roller was rotated on the surface of the plate-shaped catalyst base material used in Example 8 to form a thin catalyst component layer on the base material surface. After that, it is dried and further at 500 ° C for 2
After calcining for hours, a catalyst was obtained.
【００３３】このときの触媒添着量は約１０ｇ／ｍ2 で
あった。実施例８および９で得られた触媒の脱硝率とＳ
Ｏ2 酸化率とを前記表１および表２の条件で測定し、同
一触媒添着量である実施例３および２と比較して表４に
示した。At this time, the catalyst impregnation amount was about 10 g / m 2 . The NOx removal rate and S of the catalysts obtained in Examples 8 and 9
The O 2 oxidation rate was measured under the conditions shown in Tables 1 and 2 above, and is shown in Table 4 in comparison with Examples 3 and 2 having the same catalyst loading.
【００３４】[0034]
【表４】 表４から明らかなように、実施例８または９の方法にお
いても同様に脱硝率が高く、ＳＯ2 酸化活性の低い触媒
が得られることがわかる。上記実施例では触媒内部が酸
化チタンと酸化モリブデン、または酸化チタンと酸化タ
ングステンの例を示したが、酸化チタン、酸化モリブデ
ン、酸化タングステンの３成分でも同様の効果が得られ
た。また、上記実施例では、触媒基材として無機繊維製
基材を用いたが、本発明はこれに限定されるものではな
く、ステンレス製エクスパンドメタルなどの多孔板を用
いることもできる。また、触媒表層部の触媒組成とし
て、酸化チタン、酸化モリブデン、または酸化タングス
テンおよび酸化バナジウムよりなる３成分系を示した
が、上記４つの成分が共存する４成分系についても同様
の効果が得られる。また、表層部が酸化チタンと酸化バ
ナジウムの２成分であっても活性の点では問題ないが、
汚れた排ガスで使用するには問題がある。[Table 4] As is clear from Table 4, it can be seen that also in the method of Example 8 or 9, a catalyst having a high denitration rate and a low SO 2 oxidation activity can be obtained. In the above examples, examples of titanium oxide and molybdenum oxide or titanium oxide and tungsten oxide inside the catalyst were shown, but similar effects were obtained with three components of titanium oxide, molybdenum oxide and tungsten oxide. Further, although the inorganic fiber base material is used as the catalyst base material in the above embodiments, the present invention is not limited to this, and a perforated plate such as stainless expanded metal can also be used. Further, as the catalyst composition of the catalyst surface layer portion, a three-component system composed of titanium oxide, molybdenum oxide, or tungsten oxide and vanadium oxide is shown, but the same effect can be obtained also with a four-component system in which the above four components coexist. . Also, even if the surface layer portion is composed of two components of titanium oxide and vanadium oxide, there is no problem in terms of activity,
There are problems with using dirty exhaust gas.
【００３５】[0035]
【発明の効果】本発明により非常に少ない触媒成分の使
用量で活性が高く、実用上好ましくないＳＯ2 酸化率が
きわめて低い触媒が実現できる。これにより、従来触媒
では使用量を増して脱硝率を高めようとするとＳＯ2 酸
化率も高くなるため、実施できなかったＳＯ2 含有排ガ
スでの高脱硝率運転が可能になり、環境保全にも大きく
貢献することができるようになる。Industrial Applicability According to the present invention, a catalyst having a high activity and a very low SO 2 oxidation rate, which is not practically preferable, can be realized with a very small amount of the catalyst component used. As a result, when the conventional catalyst is used to increase the denitrification rate to increase the denitrification rate, the SO 2 oxidation rate also rises, enabling high denitrification rate operation with SO 2 -containing exhaust gas, which could not be performed, and environmental conservation. You will be able to make a significant contribution.
【図１】本発明の触媒の概要を示す図。FIG. 1 is a diagram showing an outline of a catalyst of the present invention.
【図２】従来触媒の問題点を明らかにするための触媒内
部におけるＮＯｘとＳＯ2 の濃度分布を示す図。FIG. 2 is a graph showing the concentration distribution of NOx and SO 2 inside the catalyst for clarifying the problems of the conventional catalyst.
【図３】本発明の触媒と従来触媒の性能を比較した図。FIG. 3 is a diagram comparing the performance of the catalyst of the present invention with that of a conventional catalyst.
１…高Ｖ濃度層、２…低Ｖ濃度層。 1 ... High V concentration layer, 2 ... Low V concentration layer.
─────────────────────────────────────────────────────
─────────────────────────────────────────────────── ───
【手続補正書】[Procedure amendment]
【提出日】平成８年７月１２日[Submission date] July 12, 1996
【手続補正１】[Procedure amendment 1]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００２９[Name of item to be corrected] 0029
【補正方法】変更[Correction method] Change
【補正内容】[Correction contents]
【００２９】[0029]
【表１】 [Table 1]
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 37/04 １０２ Ｂ０１Ｄ 53/36 １０２Ｃ １０２Ｈ Continuation of the front page (51) Int.Cl. 6 Identification number Office reference number FI technical display location B01J 37/04 102 B01D 53/36 102C 102H
Claims (11)
たは酸化タングステン、ならびに酸化バナジウムを活性
成分とする窒素酸化物除去用触媒において、該触媒が成
形体触媒であり、該触媒成形体の表面部のバナジウム含
有量が内部のそれより高いことを特徴とする排ガス中の
窒素酸化物除去用触媒。1. A catalyst for removing nitrogen oxides containing titanium oxide, molybdenum oxide and / or tungsten oxide, and vanadium oxide as active components, wherein the catalyst is a shaped catalyst, and vanadium on the surface of the shaped catalyst body. A catalyst for removing nitrogen oxides in exhaust gas, which is characterized by having a higher content than that in the interior.
高バナジウム含有量層がコーティングにより形成された
酸化チタン、酸化モリブデンおよび／または酸化タング
ステン、ならびに酸化バナジウムとからなる触媒成分層
であることを特徴とする排ガス中の窒素酸化物除去用触
媒。2. The catalyst according to claim 1, wherein the high vanadium content layer on the surface is a catalyst component layer formed by coating with titanium oxide, molybdenum oxide and / or tungsten oxide, and vanadium oxide. A catalyst for removing nitrogen oxides in exhaust gas, which is characterized by:
触媒表面の高バナジウム含有触媒層が厚み０．１mm以下
で、かつ単位面積当たりのコーティング量が１００ｇ／
ｍ2 以下であることを特徴とする排ガス中の窒素酸化物
除去用触媒。3. The catalyst according to claim 1 or 2, wherein
The high vanadium-containing catalyst layer on the catalyst surface has a thickness of 0.1 mm or less, and the coating amount per unit area is 100 g /
A catalyst for removing nitrogen oxides in exhaust gas, which is characterized by having m 2 or less.
において、触媒内部および触媒表面の総バナジウム含有
率が０．５ｗｔ％以下であることを特徴とする排ガス中
の窒素酸化物除去用触媒。4. The catalyst for removing nitrogen oxides from exhaust gas according to claim 1, wherein the total vanadium content in the catalyst and on the surface of the catalyst is 0.5 wt% or less. .
において、触媒内部が酸化チタンと酸化モリブデン、酸
化チタンと酸化タングステン、または酸化チタンと酸化
モリブデンと酸化タングステンであることを特徴とする
排ガス中の窒素酸化物除去用触媒。5. The exhaust gas according to claim 1, wherein the inside of the catalyst is titanium oxide and molybdenum oxide, titanium oxide and tungsten oxide, or titanium oxide, molybdenum oxide and tungsten oxide. Catalyst for removing nitrogen oxides.
において、触媒基材である網状無機繊維物間および網目
間に酸化チタンと酸化モリブデン、または酸化チタンと
酸化タングステン、酸化チタンと酸化モリブデンと酸化
タングステンを主成分とする酸化物が埋められた状態の
板状成形体表面に高バナジウム含有成分層が形成された
ことを特徴とする排ガス中の窒素酸化物除去用触媒。6. The catalyst according to any one of claims 1 to 5, wherein titanium oxide and molybdenum oxide, titanium oxide and tungsten oxide, titanium oxide and molybdenum oxide are present between the reticulated inorganic fiber materials which are the catalyst base material and between the reticulated inorganic fiber materials. A catalyst for removing nitrogen oxides in exhaust gas, wherein a high vanadium-containing component layer is formed on the surface of a plate-shaped compact filled with an oxide containing tungsten oxide as a main component.
タングステン、および酸化バナジウムとを活性成分とす
る窒素酸化物除去用触媒の製造方法において、酸化チタ
ンと酸化モリブデン、酸化チタンと酸化タングステン、
または酸化チタンと酸化ケイ素を主成分とする触媒基材
成形体を形成し、これを乾燥、焼成したのち、この表面
に高バナジウム含有触媒成分のスラリを塗布することを
特徴とする排ガス中の窒素酸化物除去用触媒の製造方
法。7. A method for producing a nitrogen oxide removing catalyst containing titanium oxide, molybdenum oxide or tungsten oxide, and vanadium oxide as active components, wherein titanium oxide and molybdenum oxide, titanium oxide and tungsten oxide,
Alternatively, nitrogen in exhaust gas is characterized in that a catalyst base material molded body containing titanium oxide and silicon oxide as main components is formed, dried and fired, and then a slurry of a catalyst component having a high vanadium content is applied to the surface thereof. A method for producing a catalyst for removing oxides.
タングステン、および酸化バナジウムを活性成分とする
窒素酸化物除去用触媒の製造方法において、酸化チタン
と酸化モリブデン、酸化チタンと酸化タングステン、ま
たは酸化チタンと酸化ケイ素を主成分とする湿式触媒基
材成形体を形成し、この湿式成形体に高バナジウム含有
触媒成分を担持させたのち、乾燥、焼成することを特徴
とする排ガス中の窒素酸化物除去用触媒の製造方法。8. A method for producing a catalyst for removing nitrogen oxides containing titanium oxide, molybdenum oxide or tungsten oxide, and vanadium oxide as active components, wherein titanium oxide and molybdenum oxide, titanium oxide and tungsten oxide, or titanium oxide and oxide are used. A catalyst for removing nitrogen oxides in exhaust gas, which comprises forming a wet catalyst base molded body containing silicon as a main component, supporting a catalyst component having a high vanadium content on the wet molded body, and then drying and firing. Manufacturing method.
て、スラリの担持手段が、スラリを一旦弾性を有するロ
ーラに付着させた後、ローラを前記湿式成形体表面と接
触させて、該成形体表面にスラリを転着することを特徴
とする排ガス中の窒素酸化物除去用触媒の製造方法。9. The method for producing a catalyst according to claim 8, wherein the slurry carrying means temporarily attaches the slurry to a roller having elasticity, and then the roller is brought into contact with the surface of the wet molded body to form the molded body. A method for producing a catalyst for removing nitrogen oxides in exhaust gas, which comprises transferring slurry to a surface.
て、湿式成形体への高バナジウム含有触媒成分の担持方
法が、上記湿式成形体と高バナジウム含有触媒成分粉末
とを接触させることにより行われ、これにより該湿式成
形体表面に高バナジウム含有成分層が形成されることを
特徴とする排ガス中の窒素酸化物除去用触媒の製造方
法。10. The method for producing a catalyst according to claim 8, wherein the method of supporting the high vanadium-containing catalyst component on the wet compact is carried out by bringing the wet compact into contact with the high vanadium-containing catalyst component powder. A method for producing a catalyst for removing nitrogen oxides in exhaust gas, which comprises forming a high vanadium-containing component layer on the surface of the wet compact.
する排ガス中の窒素酸化物除去方法において、前記排ガ
スをアンモニアの存在下、請求項１ないし６のいずれか
記載の触媒と接触させて、前記窒素酸化物をアンモニア
により還元することを特徴とする排ガス中の窒素酸化物
除去方法。11. A method for removing nitrogen oxides in exhaust gas containing sulfur dioxide together with nitrogen oxides, wherein the exhaust gas is contacted with the catalyst according to claim 1 in the presence of ammonia to produce the nitrogen gas. A method for removing nitrogen oxides in exhaust gas, which comprises reducing oxides with ammonia.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8030807A JPH09220468A (en) | 1996-02-19 | 1996-02-19 | Catalyst for removal of nox in exhaust gas, its production and method for removing nox in exhaust gas using same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8030807A JPH09220468A (en) | 1996-02-19 | 1996-02-19 | Catalyst for removal of nox in exhaust gas, its production and method for removing nox in exhaust gas using same |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2006264883A Division JP4824516B2 (en) | 2006-09-28 | 2006-09-28 | Method for producing catalyst for removing nitrogen oxides in exhaust gas |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH09220468A true JPH09220468A (en) | 1997-08-26 |
Family
ID=12313967
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8030807A Pending JPH09220468A (en) | 1996-02-19 | 1996-02-19 | Catalyst for removal of nox in exhaust gas, its production and method for removing nox in exhaust gas using same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH09220468A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000126591A (en) * | 1998-08-19 | 2000-05-09 | Ishikawajima Harima Heavy Ind Co Ltd | Denitrification catalyst |
| JP2001276617A (en) * | 2000-03-31 | 2001-10-09 | Nippon Shokubai Co Ltd | Denitration catalyst and denitration method |
| JP2007296449A (en) * | 2006-04-28 | 2007-11-15 | Babcock Hitachi Kk | Method for preparing plate-shaped denitrification catalyst |
| WO2009119639A1 (en) | 2008-03-25 | 2009-10-01 | バブコック日立株式会社 | Exhaust gas purification catalyst on which influence of iron compound has been suppressed |
| JP2014522305A (en) * | 2011-05-30 | 2014-09-04 | バブコック・アンド・ウィルコックス・パワー・ジェネレイション・グループ・インコーポレイテッド | Catalyst with improved poison resistance |
| JP2017060945A (en) * | 2011-08-03 | 2017-03-30 | ジョンソン、マッセイ、パブリック、リミテッド、カンパニーＪｏｈｎｓｏｎ Ｍａｔｔｈｅｙ Ｐｕｂｌｉｃ Ｌｉｍｉｔｅｄ Ｃｏｍｐａｎｙ | Extrusion molded honeycomb catalyst |
| CN115739081A (en) * | 2022-12-28 | 2023-03-07 | 大唐(江苏)环保装备公司 | Denitration catalyst and preparation method thereof |
-
1996
- 1996-02-19 JP JP8030807A patent/JPH09220468A/en active Pending
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000126591A (en) * | 1998-08-19 | 2000-05-09 | Ishikawajima Harima Heavy Ind Co Ltd | Denitrification catalyst |
| JP4505873B2 (en) * | 1998-08-19 | 2010-07-21 | 株式会社Ｉｈｉ | Denitration method |
| JP2001276617A (en) * | 2000-03-31 | 2001-10-09 | Nippon Shokubai Co Ltd | Denitration catalyst and denitration method |
| JP2007296449A (en) * | 2006-04-28 | 2007-11-15 | Babcock Hitachi Kk | Method for preparing plate-shaped denitrification catalyst |
| WO2009119639A1 (en) | 2008-03-25 | 2009-10-01 | バブコック日立株式会社 | Exhaust gas purification catalyst on which influence of iron compound has been suppressed |
| JP2014522305A (en) * | 2011-05-30 | 2014-09-04 | バブコック・アンド・ウィルコックス・パワー・ジェネレイション・グループ・インコーポレイテッド | Catalyst with improved poison resistance |
| JP2017060945A (en) * | 2011-08-03 | 2017-03-30 | ジョンソン、マッセイ、パブリック、リミテッド、カンパニーＪｏｈｎｓｏｎ Ｍａｔｔｈｅｙ Ｐｕｂｌｉｃ Ｌｉｍｉｔｅｄ Ｃｏｍｐａｎｙ | Extrusion molded honeycomb catalyst |
| US10443472B2 (en) | 2011-08-03 | 2019-10-15 | Johnson Matthey Public Limited Company | Extruded honeycomb catalyst |
| CN115739081A (en) * | 2022-12-28 | 2023-03-07 | 大唐(江苏)环保装备公司 | Denitration catalyst and preparation method thereof |
| CN115739081B (en) * | 2022-12-28 | 2024-02-09 | 大唐(江苏)环保装备公司 | Denitration catalyst and preparation method thereof |
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