JPS6225417B2 - - Google Patents
Info
- Publication number
- JPS6225417B2 JPS6225417B2 JP54085243A JP8524379A JPS6225417B2 JP S6225417 B2 JPS6225417 B2 JP S6225417B2 JP 54085243 A JP54085243 A JP 54085243A JP 8524379 A JP8524379 A JP 8524379A JP S6225417 B2 JPS6225417 B2 JP S6225417B2
- Authority
- JP
- Japan
- Prior art keywords
- catalyst
- molded body
- silica
- exhaust gas
- calcium silicate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 239000003054 catalyst Substances 0.000 claims description 59
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 33
- VTYYLEPIZMXCLO-UHFFFAOYSA-L calcium carbonate Substances [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 claims description 31
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims description 25
- 239000000378 calcium silicate Substances 0.000 claims description 25
- 229910052918 calcium silicate Inorganic materials 0.000 claims description 25
- OYACROKNLOSFPA-UHFFFAOYSA-N calcium;dioxido(oxo)silane Chemical compound [Ca+2].[O-][Si]([O-])=O OYACROKNLOSFPA-UHFFFAOYSA-N 0.000 claims description 25
- 229910000019 calcium carbonate Inorganic materials 0.000 claims description 22
- 239000002131 composite material Substances 0.000 claims description 17
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 17
- 239000002002 slurry Substances 0.000 claims description 16
- 239000001569 carbon dioxide Substances 0.000 claims description 12
- 229910002092 carbon dioxide Inorganic materials 0.000 claims description 12
- 238000004519 manufacturing process Methods 0.000 claims description 11
- 238000001035 drying Methods 0.000 claims description 6
- 238000010304 firing Methods 0.000 claims description 3
- 239000011882 ultra-fine particle Substances 0.000 claims description 3
- 229910052720 vanadium Inorganic materials 0.000 claims description 3
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 claims description 3
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 2
- 239000010936 titanium Substances 0.000 claims description 2
- 229910052719 titanium Inorganic materials 0.000 claims description 2
- 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 1
- 229910001930 tungsten oxide Inorganic materials 0.000 claims 1
- 239000007789 gas Substances 0.000 description 38
- 238000000034 method Methods 0.000 description 26
- 239000013078 crystal Substances 0.000 description 17
- 238000012360 testing method Methods 0.000 description 14
- 238000006243 chemical reaction Methods 0.000 description 10
- 239000000377 silicon dioxide Substances 0.000 description 10
- 239000000243 solution Substances 0.000 description 10
- 229910052815 sulfur oxide Inorganic materials 0.000 description 10
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 9
- 239000000463 material Substances 0.000 description 9
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 8
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 description 8
- 239000000428 dust Substances 0.000 description 7
- 239000000741 silica gel Substances 0.000 description 7
- 229910002027 silica gel Inorganic materials 0.000 description 7
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 6
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 6
- 239000002994 raw material Substances 0.000 description 6
- 239000010425 asbestos Substances 0.000 description 5
- 238000010531 catalytic reduction reaction Methods 0.000 description 5
- 229910052895 riebeckite Inorganic materials 0.000 description 5
- 235000012239 silicon dioxide Nutrition 0.000 description 5
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 4
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 4
- 235000011941 Tilia x europaea Nutrition 0.000 description 4
- 239000004480 active ingredient Substances 0.000 description 4
- 230000008602 contraction Effects 0.000 description 4
- GNTDGMZSJNCJKK-UHFFFAOYSA-N divanadium pentaoxide Chemical compound O=[V](=O)O[V](=O)=O GNTDGMZSJNCJKK-UHFFFAOYSA-N 0.000 description 4
- 239000003365 glass fiber Substances 0.000 description 4
- 239000004571 lime Substances 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- 230000002378 acidificating effect Effects 0.000 description 3
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 3
- 239000003245 coal Substances 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 238000002485 combustion reaction Methods 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 229910052602 gypsum Inorganic materials 0.000 description 3
- 239000010440 gypsum Substances 0.000 description 3
- 238000002156 mixing Methods 0.000 description 3
- 238000000465 moulding Methods 0.000 description 3
- 239000011819 refractory material Substances 0.000 description 3
- 238000003756 stirring Methods 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 239000005909 Kieselgur Substances 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 description 2
- 229910004283 SiO 4 Inorganic materials 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 238000002441 X-ray diffraction Methods 0.000 description 2
- 229910021536 Zeolite Inorganic materials 0.000 description 2
- 230000005856 abnormality Effects 0.000 description 2
- 239000000654 additive Substances 0.000 description 2
- 229910021529 ammonia Inorganic materials 0.000 description 2
- 238000005452 bending Methods 0.000 description 2
- UGGQKDBXXFIWJD-UHFFFAOYSA-N calcium;dihydroxy(oxo)silane;hydrate Chemical compound O.[Ca].O[Si](O)=O UGGQKDBXXFIWJD-UHFFFAOYSA-N 0.000 description 2
- 239000000969 carrier Substances 0.000 description 2
- 239000003638 chemical reducing agent Substances 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 description 2
- 239000000446 fuel Substances 0.000 description 2
- 239000000295 fuel oil Substances 0.000 description 2
- 238000001027 hydrothermal synthesis Methods 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 235000006408 oxalic acid Nutrition 0.000 description 2
- 239000007858 starting material Substances 0.000 description 2
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 2
- CMPGARWFYBADJI-UHFFFAOYSA-L tungstic acid Chemical compound O[W](O)(=O)=O CMPGARWFYBADJI-UHFFFAOYSA-L 0.000 description 2
- 239000010457 zeolite Substances 0.000 description 2
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 239000012298 atmosphere Substances 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 235000011089 carbon dioxide Nutrition 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 239000000571 coke Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000011010 flushing procedure Methods 0.000 description 1
- 239000008187 granular material Substances 0.000 description 1
- 238000005469 granulation Methods 0.000 description 1
- 230000003179 granulation Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000005470 impregnation Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 238000004898 kneading Methods 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- -1 naphtha Substances 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 238000002203 pretreatment Methods 0.000 description 1
- 239000001294 propane Substances 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- KKCBUQHMOMHUOY-UHFFFAOYSA-N sodium oxide Chemical compound [O-2].[Na+].[Na+] KKCBUQHMOMHUOY-UHFFFAOYSA-N 0.000 description 1
- 229910001948 sodium oxide Inorganic materials 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- XTQHKBHJIVJGKJ-UHFFFAOYSA-N sulfur monoxide Chemical class S=O XTQHKBHJIVJGKJ-UHFFFAOYSA-N 0.000 description 1
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 239000010937 tungsten Substances 0.000 description 1
Landscapes
- Exhaust Gas Treatment By Means Of Catalyst (AREA)
- Catalysts (AREA)
Description
本発明は窒素酸化物含有ガスの処理触媒の製造
方法の改良に関し特に重油焚きボイラ、石炭焚き
ボイラ、各種の化学装置に付設する燃焼炉などか
ら排出されるダスト、及び硫黄酸化物(以下SOx
と略称する)を多量に含有する排ガス中の窒素酸
化物(以下NOxと略称する)を無害化除去する
場合に用いて好適な触媒の製造方法に関するもの
である。
排ガス中のNOx除去方法としては吸着法、酸
化吸収法、固体化捕集法、接触還元法などがある
が、後処理不要の接触還元法が経済的、技術的に
も有利であるため各方面で開発が試みられてい
る。
接触還元反応も還元剤の選択により二種類の方
法が考えられるが、排ガス中の酸素の有無による
影響を受けない選択的接触還元法が経済的にも有
利である。本発明はこの反応に適用しうる触媒に
関するものであり特にNH3を還元剤とした場合が
有利であるため以下この方法によつて更に本発明
を詳述する。
従来選択的接触還元プロセスに適用する触媒の
担体としてはアルミナ、チタニア、ジルコニア、
シリカ、ケイソウ土、ゼオライトなどの多孔性耐
火物質を単独あるいは組合せて使用していたが、
いずれも造粒して使用するため高価となる上に、
活性賦与成分を担持させるため触媒製造コストが
嵩むという欠点があつた。
ところで蒸留油やガス燃料(例えばLNG、
LPG)からの排ガス中にはダストが皆無に近い状
態であるため、前述の担体を球状、円筒状などの
任意の形状に造粒成形し、触媒層へ垂直に排ガス
を接触させることが可能である。一方重油、ナフ
サ、石炭を燃料としたボイラ排ガス、ゴミ焼却
炉、コークス炉排ガスなどのダストを多量に含有
する排ガス処理技術の開発にはダストの触媒層へ
の蓄積防止の対策を講じる必要がある。そのため
に触媒形状を円筒状、ハニカム状などにしてダス
トの通過を容易にさせる方法、粒状触媒を移動す
ることにより付着ダストを飛散させる方法などが
検討されているが、排ガスを触媒層に並行流で流
すことによりダストの付着を防止する方法も有望
であり、本発明者らもこの方式に適用しうる触媒
の開発に鋭意取り組んでいる。この方式での最適
の触媒形状は板状構造体であり前述の多孔性耐火
物質を大型の板に成形することは現状では困難で
あるため、安価に製造でき軽量で、かなりの強度
を有する担体材料が望まれる。しかも、重油、石
炭などを燃料としたボイラ排ガス中には、ダスト
の他に硫黄酸化物(SOx)が含まれるため、SOx
に安定な材料であることも望まれる。
上述の点を考慮し、本発明者らはこの要求に適
合する担体及び触媒について研究した結果、先に
提案した特願昭52−16874号の方法、即ち珪酸と
石灰を主原料としたスラリー物質に必要に応じて
石綿、ガラス繊維などの無機添加剤を混合し、加
熱、加圧下で反応させて得られる珪酸カルシウム
を担体とし、これに活性成分を担持させた触媒及
びその製造方法の発明であるが、本発明は更に先
願発明を発展させ、軽量で安価、かつSOxにも極
めて安定な触媒の製造方法を発明するに至つた。
すなわち先に提案した上述の触媒は担体として
安価な珪酸原料と石灰原料に必要に応じて石綿、
ガラス繊維などの無機添加剤を混合し、水に懸濁
して得られるスラリー状の物質を5〜20Kg/cm2程
度の加圧下、150〜300℃で加熱、撹拌しながら、
あるいは、一時撹拌を中止して水熱合成反応と結
晶化を進めて得られる珪酸カルシウム結晶の活性
スラリーを成形し、乾燥して作られる珪酸カルシ
ウム成形体を使用し、これに触媒とするための活
性成分を担持させたものであり安価に製造できる
こと、軽量でかつ強度面において優れるところに
大きな特徴を有する。
しかし、石炭焚きボイラの如く、特にSOxを多
量に含有する排ガスに適用した場合は担体基材で
ある珪酸カルシウムがSOx特にSO3と急激に反応
し、これが石こうとシリカに分離して強度低下及
び熱変形に伴うクラツクを生じるなど触媒担体と
して必ずしも完全なものとは言いがたい点があつ
た。珪酸カルシウムと排ガス中のSO3との反応は
次式によつて進行し石こうとシリカに分離する
が、SO3の如く強い酸性ガスと接触した場合は、
反応によつて分離するシリカの結晶も強度的に弱
くなり、このため触媒の構造体自体に極度の強度
低下と熱歪みによるクラツクを生じることとなる
6CaO・6SiO2・H2O+6SO3+nH2O→6CaSO4+6SiO2・nH2O
そこで本発明者らは珪酸カルシウム組成中の
CaOとSO3との急激な反応を避けるため、担体の
前処理方法について実験検討を重ねた結果、少な
くともSO3と反応しやすい、CaOを弱酸性の物質
で予め中性化させ、強度不変のシリカ結晶に分離
転換しておけば解決可能なこと、更にはこの弱酸
性の物質として二酸化炭素が特に好ましいことを
見出し特開昭52−8024に記載のシリカ−炭酸カル
シウム複合成形体を担体とした触媒の製造方法に
関する本発明を完成するに至つた。
すなわち本発明者らは珪酸カルシウム系成形体
の中性化処理についての検討過程において、上記
成形体を積極的に炭酸ガスにより炭酸化する場合
には、その成形体を構成する珪酸カルシウムはシ
リカゲルと炭酸カルシウムに転化されるにもかか
わらずその成形体の形状は実質的に変化せずしか
もその強度を保持しかくして得られるシリカ−炭
酸カルシウムの複合成形体は硫酸及び塩酸のよう
な強い酸と接触させても、その形状及び強度を保
持したままの状態にあるというおどろくべき事実
を見出し本発明を完成した。
本発明はこの知見にもとづいて完成されたもの
であつて、珪酸カルシウム系成形体に炭酸ガスを
一定時間接触させ、得られるシリカ−炭素カルシ
ウム複合体を触媒用担体として、これを触媒とす
るべく、無水珪酸の超微粒子を水中に分散させた
コロイド溶液に浸漬し、次いでチタン、バナジウ
ム、タングステンの酸化物を含有するスラリーに
浸漬後、乾燥、焼成することにより成る排ガス処
理用触媒の製造方法を骨子とするものである。
本発明方法において出発材料とする珪酸カルシ
ウム成形体としては、その製造方法やこれを構成
する珪酸カルシウムの結晶化度、結晶系等にかか
わることなく珪酸カルシウムを主成分とする各種
成形体がいずれも使用可能である。
例えば珪酸カルシウムについて云えば、その製
造方法によりゾノトライト、トベルモライト、フ
オシヤジヤイト、ジヤイロライト、準結晶質珪酸
カルシウム(CSHr)等の各種結晶化度の異なる
組成のものが得られ、いずれも使用可能であるが
特に触媒用担体としての適性をみた場合はゾノト
ライト結晶(6CaO・6SiO2・H2O)からなるもの
が好ましく強度面、熱特性に優れる点で好適であ
る。
本発明において珪酸カルシウム系成形体の炭酸
化は上記成形体を炭酸ガスと接触せしめることに
より簡単に行なわれる。この場合、常温でしかも
短時間で炭酸化反応を完結させるには水分の存在
下で強制的に行うことが好ましく通常は上記成形
体を適当な容器に入れ高湿度下ないしは湿潤雰囲
気下で、その容器中に炭酸ガスを導入することに
より、あるいは珪酸カルシウム系成形体を水中、
もしくは炭酸水中に浸漬後、これに炭酸ガスを導
入するなどの方法により実施できる。又、珪酸カ
ルシウム系成形体を製造する過程において例え
ば、珪酸原料と石灰原料とを水に懸濁せしめて
後、加圧、加熱下で撹拌して得られるスラリーを
成形した直後において、水分を含んだ状態での成
形体を乾燥と同時に炭酸ガスを吹込むか、あるい
は燃焼排ガス中の炭酸ガスを利用するかで実施で
きる。この場合、燃焼排ガスを利用する際はSOx
を含まないようクリーンなガス燃料が好ましい。
かくして成形体を構成する珪酸カルシウムはそ
の晶癖を実質的に変化させることなく偽結晶質シ
リカゲルと炭酸カルシウムの微粒結晶とに転化さ
れる。即ち珪酸カルシウム結晶の骨格構造をなす
SiO4四面体の連鎖構造をそのまま保持し、その
連鎖構造によつて結晶形態を保持した偽結晶質シ
リカゲルとその偽結晶質シリカゲルに付着して存
在する極微細炭酸カルシウムが生成するのであ
る。本発明における上記炭酸化反応をゾノトライ
ト結晶からなる珪酸カルシウムで例示すれば次の
とおりとなる。
6CaO・6SiO2・H2O+6CO2+nH2O→6CaCO3+6SiO2・nH2O
上記で示される反応式により偽結晶質シリカゲ
ルと極微細炭酸カルシウムが得られるという事実
は電子顕微鏡観察、X線回析及び化学分析結果か
ら認められる。
以上のようにして得られるシリカ−炭酸カルシ
ウムの複合成形体をSOxを多量に含有する排ガス
と接触させた場合は次式に示すように極微細炭酸
カルシウムは石こうに転化するが、偽結晶質シリ
カゲルはSiO4四面体の連鎖構造を保持したまま
の状態で、一つの強度構成材として残り、かりに
SOxとの急激な反応が起つても極度な強度低下及
び熱歪みによるクラツクなどを引き起す恐れがな
い。
6CaO3+6SiO2・nH2O+6SO3→6CaSO4+6SiO2・nH2O+6CO2↑
次に上記、シリカ炭酸カルシウムの複合成形体
を脱硝触媒とするための活性成分の担持方法であ
るが、これについては従来公知のアルミナ、チタ
ニア、ジルコニア、シリカ、ケイソウ土、ゼオラ
イトへの担持法と同様の操作が可能である。担持
法としては一般に混練法、含浸法、塗布法などが
知られているがシリカ−炭酸カルシウムの複合成
形体への担持法としては、その成形体を単なる基
材と考えこの表面に触媒活性成分を塗布する方法
が好適である。
本発明において担体としてのシリカ−炭酸カル
シウムの複合成形体を無水珪酸の超微粒子を水中
に分散させたコロイド溶液(以下“シリカゾル”
と略称する)に浸漬する理由は、上記シリカ炭酸
カルシウムの複合成形体と触媒活性成分との接着
性をよくするためのものであり、本発明はこのシ
リカゾルに浸漬することによつて基材であるシリ
カ炭酸カルシウム複合成形体中の偽結晶質シリカ
ゲルとのなじみをよくし、その上に触媒となる活
性成分を塗着させることを特徴とするものであ
る。
触媒成分は従来から知られている、アルミナ、
チタニア、シリカ、ジルコニアなどの多孔性耐火
物にバナジウム、クロム、鉄、ニツケル、銅など
の金属酸化物又は硫酸塩などを担持させたものが
適用しうる。この時、触媒自体をスラリー溶液に
しておいて、予め接着剤としてのシリカゾル中に
シリカ炭酸カルシウム複合成形体を浸漬し、次い
で上記スラリー溶液に浸漬し、乾燥するだけの方
法でも良いが、本発明方法は触媒となるべき成分
を含有するスラリー溶液中に浸漬したる後、乾
燥、焼成することで基材との結合性を増加させる
ところに特徴を有する。
以下、実施例により詳述する。
実施例 1
石灰と珪酸とのモル比を0.98とし、水対固形分
の比を12/1とした原料スラリーを12Kg/cm2
(191℃)の加圧下で8時間撹拌しながら、水熱反
応させて得た、ゾノトライト結晶(6CaO・
6SiO2・H2O)のスラリーにガラス繊維と石綿を
ゾノトライト結晶の重量に対して3%wtおよび
6%wt添加し充分に混合した後、このスラリー
を型枠に入れプレス脱水成形し、120〜150℃で10
時間乾燥して珪酸カルシウム成形体を得た。この
成形体を水中に浸漬し、水分60%(wt)を含ま
せて容器中に入れこれに炭酸ガスを導入して、常
温、常圧下で約30時間反応させシリカ−炭酸カル
シウム複合成形体を得た。
実施例 2
実施例1で得た珪酸カルシウム成形体を湿潤雰
囲気の容器中に入れ常温で炭酸ガスを圧入して3
Kg/cm2の内圧とし、約30分間反応させてシリカ−
炭酸カルシウムの複合成形体を得た。
実施例 3
石灰と珪酸とのモル比を0.83とし水対固形分の
重量比を12/1として8Kg/cm2(175℃)で撹拌
しながら水熱反応させてトベルモライト結晶
(5CaO・6SiO2・5H2O)のスラリーを得、これに
ガラス繊維と石綿をトベルモライト結晶の重量に
対して3%wtと6%wt添加し、これを実施例1
と同様に成形乾燥して珪酸カルシウム成形体を得
た。この成形体に約100%の水分を含有させたの
ち、ドライアイスを入れた容器内におき炭酸ガス
を発生させて常温、常圧で約10時間反応させたシ
リカ−炭酸カルシウムの複合成形体を得た。
実施例 4
石炭と珪酸のモル比を0.98とし実施例1と同様
の方法で水熱反応させて得たゾノトライト結晶
(6CaO・6SiO2・H2O)のスラリーを型枠に入れ
てプレス成形し、直後の水分約180%を含有する
状態の成形体を、150℃のプロパン燃焼排ガス中
に約3時間おきシリカ−炭酸カルシウムの複合成
形体を得た。
実施例 5
実施例1、2、3、4で得たシリカ−炭酸カル
シウムの複合成形体をX線回折でみたところ、い
ずれも出発材料を構成するゾノトライト結晶
(6CaO・6SiO2・H2O)及びトベルモライト結晶
(5CaO・6SiO2・5H2O)は消失し、代りに炭酸カ
ルシウムの結晶が確認された。
実施例 6
実施例1、2、3、4で得たシリカ−炭酸カル
シウムの複合成形体を各々200×400×10mmtの大
きさに切断し、各々の成形体を無水珪酸20〜21
%、酸化ナトリウム0.04%以下を含有するコロイ
ド溶液(PH3〜4)に10分間浸漬し、乾燥が不十
分な状態で五酸化バナジウム20gをシユウ酸50g
と水1200gで溶解した溶液に酸化チタン1000gと
タングステン酸80gを混合したスラリー液中に約
1分間浸漬し、150℃にて3時間乾燥後、次に550
℃で5時間焼成して各々の触媒を得た。
試験例 1
実施例6で得た本発明触媒の耐SOx性をみるた
めSOx1000〜1500ppm、SO320〜30ppmを含有す
る重油焚きボイラ排ガス中に触媒をおき、350〜
380℃で耐久試験を行つた結果、5000時間後も異
常なく強度低下やクラツクの発生は認められなか
つた。これに対し比較触媒として炭酸化しない珪
酸カルシウム成形体を実施例6に準じて調製した
触媒はクラシクが発生し強度も約1/2に低下し
た。又、五酸化バナジウム20gをシユウ酸50gと
水1200gで溶解した溶液に酸化チタン1000gとタ
ングステン酸80gを混合したスラリー液中に実施
例1で得たシリカ−炭酸カルシウム複合成形体を
直ちに浸漬し、150℃で3時間乾燥、次いで550℃
で5時間焼成して得た触媒についても、比較のた
め同様の耐久試験を行つた結果、成形体への触媒
成分の付着力が弱く、剥離が見られた。
表1に、耐久試験後の強度変化と外観変化を示
した。
The present invention relates to an improvement in the manufacturing method of a catalyst for treating nitrogen oxide-containing gases, and particularly relates to the improvement of a method for manufacturing a catalyst for treating gases containing nitrogen oxides.
The present invention relates to a method for manufacturing a catalyst suitable for use in detoxifying and removing nitrogen oxides (hereinafter abbreviated as NOx) in exhaust gas containing a large amount of NOx. Methods for removing NOx from exhaust gas include adsorption methods, oxidation absorption methods, solidification collection methods, and catalytic reduction methods, but the catalytic reduction method, which does not require post-treatment, is economically and technically advantageous and is therefore widely used in various fields. development is being attempted. There are two possible methods for the catalytic reduction reaction depending on the selection of the reducing agent, but the selective catalytic reduction method is economically advantageous as it is not affected by the presence or absence of oxygen in the exhaust gas. The present invention relates to a catalyst that can be applied to this reaction, and since it is particularly advantageous to use NH 3 as a reducing agent, the present invention will be further detailed below using this method. Conventional catalyst supports used in selective catalytic reduction processes include alumina, titania, zirconia,
Porous refractory materials such as silica, diatomaceous earth, and zeolite were used alone or in combination;
Both are expensive because they are used after granulation, and
The disadvantage is that the catalyst production cost increases because the activation-imparting component is supported. By the way, distilled oil and gas fuel (e.g. LNG,
Since there is almost no dust in the exhaust gas from LPG, it is possible to granulate the aforementioned carrier into any shape such as spherical or cylindrical, and bring the exhaust gas into contact with the catalyst layer perpendicularly. be. On the other hand, in order to develop exhaust gas treatment technology that contains a large amount of dust, such as boiler exhaust gas fueled by heavy oil, naphtha, or coal, garbage incinerator exhaust gas, and coke oven exhaust gas, it is necessary to take measures to prevent dust from accumulating in the catalyst layer. . For this purpose, methods are being considered, such as making the catalyst shape cylindrical or honeycomb-like to make it easier for the dust to pass through, and moving the granular catalyst to scatter the adhering dust. A method of preventing dust adhesion by flushing with water is also promising, and the present inventors are also working hard to develop a catalyst that can be applied to this method. The optimal catalyst shape for this method is a plate-like structure, and since it is currently difficult to form the aforementioned porous refractory material into a large plate, a carrier that can be manufactured at low cost, is lightweight, and has considerable strength. material is desired. Moreover, the exhaust gas from boilers fueled by heavy oil, coal, etc. contains sulfur oxides (SOx) in addition to dust.
It is also desirable that the material be stable. Taking the above points into consideration, the present inventors conducted research on carriers and catalysts that met these requirements, and as a result, they developed the method of Japanese Patent Application No. 16874/1985, that is, a slurry material containing silicic acid and lime as main raw materials. Invention of a catalyst in which an active ingredient is supported on a calcium silicate carrier obtained by mixing inorganic additives such as asbestos and glass fiber as necessary and reacting the mixture under heating and pressure, and a method for producing the same. However, the present invention has further developed the prior invention and has invented a method for producing a catalyst that is lightweight, inexpensive, and extremely stable against SOx. In other words, the above-mentioned catalyst proposed earlier uses cheap silicic acid raw materials and lime raw materials as carriers, and asbestos and asbestos as necessary.
A slurry-like substance obtained by mixing inorganic additives such as glass fiber and suspending it in water is heated at 150 to 300°C under a pressure of about 5 to 20 kg/cm 2 while stirring.
Alternatively, a calcium silicate molded body made by molding and drying an active slurry of calcium silicate crystals obtained by temporarily discontinuing stirring and proceeding with hydrothermal synthesis reaction and crystallization is used, and this is used as a catalyst. It carries an active ingredient, can be produced at low cost, is lightweight, and has excellent strength. However, when applied to exhaust gas containing a large amount of SOx, such as from coal-fired boilers, calcium silicate, which is the carrier base material, rapidly reacts with SOx, especially SO 3 , and this separates into gypsum and silica, resulting in a decrease in strength and It could not be said to be perfect as a catalyst carrier, such as cracks caused by thermal deformation. The reaction between calcium silicate and SO 3 in exhaust gas proceeds according to the following equation and separates into gypsum and silica, but when it comes into contact with a strong acidic gas such as SO 3 ,
The silica crystals separated by the reaction also become weaker in strength, resulting in an extreme decrease in strength and cracks due to thermal distortion in the catalyst structure itself. 6CaO・6SiO 2・H 2 O + 6SO 3 +nH 2 O →6CaSO 4 +6SiO 2・nH 2 O Therefore, the present inventors found that
In order to avoid a rapid reaction between CaO and SO 3 , we conducted repeated experiments on pretreatment methods for the carrier, and found that at least CaO, which is easily reacted with SO 3 , was neutralized in advance with a weakly acidic substance, and the strength remained unchanged. It was discovered that this problem could be solved by separating and converting it into silica crystals, and that carbon dioxide was particularly preferable as this weakly acidic substance. The present invention relating to a method for producing a catalyst has been completed. That is, in the process of studying the carbonation treatment of calcium silicate-based molded bodies, the present inventors found that when the molded bodies are actively carbonated with carbon dioxide gas, the calcium silicate constituting the molded bodies is not silica gel. Despite being converted to calcium carbonate, the shape of the compact does not substantially change, yet it retains its strength.The resulting silica-calcium carbonate composite compact remains in contact with strong acids such as sulfuric acid and hydrochloric acid. The present invention was completed based on the surprising fact that the material retains its shape and strength even when exposed to water. The present invention was completed based on this knowledge, and is intended to be used as a catalyst by contacting a calcium silicate-based molded body with carbon dioxide gas for a certain period of time, and using the resulting silica-carbon calcium composite as a catalyst carrier. , a method for producing an exhaust gas treatment catalyst comprising immersing ultrafine particles of silicic anhydride in a colloidal solution dispersed in water, then immersing them in a slurry containing oxides of titanium, vanadium, and tungsten, followed by drying and firing. This is the basic outline. The calcium silicate molded body used as the starting material in the method of the present invention may be any of various molded bodies containing calcium silicate as the main component, regardless of its manufacturing method, crystallinity, crystal system, etc. of the calcium silicate that constitutes it. Available for use. For example, regarding calcium silicate, depending on the manufacturing method, products with different crystallinity such as xonotlite, tobermolite, phosiyaite, diairolite, and quasi-crystalline calcium silicate (CSHr) can be obtained, and any of them can be used. Especially when looking at suitability as a catalyst carrier, those made of xonotrite crystals (6CaO.6SiO 2 .H 2 O) are preferable because they have excellent strength and thermal properties. In the present invention, carbonation of the calcium silicate molded body is easily carried out by bringing the molded body into contact with carbon dioxide gas. In this case, in order to complete the carbonation reaction at room temperature and in a short time, it is preferable to carry out the carbonation reaction forcibly in the presence of moisture. By introducing carbon dioxide gas into a container, or by placing a calcium silicate-based molded body in water.
Alternatively, it can be carried out by a method such as immersing it in carbonated water and then introducing carbon dioxide gas into it. In addition, in the process of producing a calcium silicate-based molded body, for example, immediately after molding a slurry obtained by suspending a silicic acid raw material and a lime raw material in water and then stirring it under pressure and heat, it is possible to remove water from the slurry. This can be carried out by blowing carbon dioxide gas into the molded product while it is still wet, or by using carbon dioxide gas in combustion exhaust gas. In this case, when using combustion exhaust gas, SOx
Clean gas fuel is preferred as it does not contain The calcium silicate constituting the compact is thus converted into pseudocrystalline silica gel and fine crystals of calcium carbonate without substantially changing its crystal habit. In other words, it forms the skeleton structure of calcium silicate crystals.
The chain structure of SiO 4 tetrahedrons is maintained, and the chain structure produces pseudocrystalline silica gel that maintains its crystalline form and ultrafine calcium carbonate that adheres to the pseudocrystalline silica gel. The above carbonation reaction in the present invention is exemplified as follows using calcium silicate consisting of xonotrite crystals. 6CaO・6SiO 2・H 2 O+6CO 2 +nH 2 O→6CaCO 3 +6SiO 2・nH 2 O The fact that pseudocrystalline silica gel and ultrafine calcium carbonate can be obtained by the reaction formula shown above has been confirmed by electron microscopic observation and X-ray diffraction. This is recognized from the analytical and chemical analysis results. When the silica-calcium carbonate composite molded body obtained as described above is brought into contact with exhaust gas containing a large amount of SOx, the ultrafine calcium carbonate is converted to gypsum as shown in the following equation, but pseudocrystalline silica gel remains as a strength component while retaining the chain structure of SiO 4 tetrahedrons.
Even if a rapid reaction with SOx occurs, there is no risk of causing an extreme decrease in strength or cracks due to thermal distortion. 6CaO 3 +6SiO 2・nH 2 O+6SO 3 →6CaSO 4 +6SiO 2・nH 2 O+6CO 2 ↑ Next, the above-mentioned method of supporting the active ingredient in order to use the silica calcium carbonate composite molded body as a denitrification catalyst will be explained. It is possible to carry out operations similar to conventional methods for supporting alumina, titania, zirconia, silica, diatomaceous earth, and zeolite. Generally known supporting methods include kneading, impregnation, and coating methods, but in order to support silica-calcium carbonate on a composite molded body, the molded body is considered to be a mere base material and the catalytically active component is added to the surface. A method of coating is suitable. In the present invention, a silica-calcium carbonate composite molded body as a carrier is used as a colloidal solution (hereinafter referred to as "silica sol") in which ultrafine particles of silicic anhydride are dispersed in water.
The reason for immersing the base material in silica sol is to improve the adhesion between the silica calcium carbonate composite molded body and the catalytically active component. It is characterized by improving compatibility with the pseudocrystalline silica gel in a certain silica-calcium carbonate composite molded body, and coating an active ingredient that becomes a catalyst thereon. The catalyst components are conventionally known alumina,
Porous refractories such as titania, silica, and zirconia supported with metal oxides or sulfates such as vanadium, chromium, iron, nickel, and copper may be used. At this time, a method may be used in which the catalyst itself is made into a slurry solution, and the silica-calcium carbonate composite molded body is immersed in advance in silica sol as an adhesive, then immersed in the slurry solution and dried, but the present invention The method is characterized in that the bonding property with the substrate is increased by immersing the material in a slurry solution containing components to become a catalyst, followed by drying and baking. Hereinafter, it will be explained in detail using examples. Example 1 A raw material slurry with a molar ratio of lime to silicic acid of 0.98 and a water to solid content ratio of 12/1 was prepared at 12 kg/cm 2
Zonotlite crystals (6CaO・
Glass fiber and asbestos were added to the slurry of 6SiO 2 H 2 O) at 3% wt and 6% wt based on the weight of the xonotlite crystals, mixed thoroughly, and then the slurry was placed in a mold and dehydrated by pressing. 10 at ~150℃
After drying for a period of time, a calcium silicate molded body was obtained. This molded body was immersed in water, and placed in a container containing 60% (wt) water, and carbon dioxide gas was introduced into it, and the mixture was allowed to react for about 30 hours at normal temperature and pressure to form a silica-calcium carbonate composite molded body. Obtained. Example 2 The calcium silicate molded body obtained in Example 1 was placed in a container with a humid atmosphere, and carbon dioxide gas was pressurized at room temperature.
The internal pressure was set to Kg/ cm2 , and the silica was reacted for about 30 minutes.
A composite molded body of calcium carbonate was obtained. Example 3 Tobermolite crystals (5CaO 6SiO A slurry of 2.5H 2 O) was obtained, to which glass fiber and asbestos were added at 3% wt and 6% wt based on the weight of tobermolite crystals, and this was used in Example 1.
A calcium silicate molded body was obtained by molding and drying in the same manner as above. After this molded body contained approximately 100% water, it was placed in a container containing dry ice to generate carbon dioxide gas and reacted at room temperature and pressure for approximately 10 hours to form a silica-calcium carbonate composite molded body. Obtained. Example 4 A slurry of xonotrite crystals (6CaO・6SiO 2・H 2 O) obtained by hydrothermal reaction in the same manner as in Example 1 with a molar ratio of coal and silicic acid of 0.98 was placed in a mold and press-formed. Immediately after, the molded product containing about 180% moisture was placed in propane combustion exhaust gas at 150° C. for about 3 hours to obtain a silica-calcium carbonate composite molded product. Example 5 When the silica-calcium carbonate composite molded bodies obtained in Examples 1, 2, 3, and 4 were examined by X-ray diffraction, all showed xonotrite crystals (6CaO・6SiO 2・H 2 O) constituting the starting material. and tobermolite crystals (5CaO・6SiO 2・5H 2 O) disappeared, and calcium carbonate crystals were confirmed instead. Example 6 The silica-calcium carbonate composite molded bodies obtained in Examples 1, 2, 3, and 4 were each cut into a size of 200 x 400 x 10 mm, and each molded body was coated with silicic anhydride 20 to 21 mm.
%, 20 g of vanadium pentoxide is immersed in a colloidal solution (PH 3-4) containing 0.04% or less of sodium oxide for 10 minutes, and 50 g of oxalic acid is soaked in an insufficiently dry state.
It was immersed in a slurry solution of 1000 g of titanium oxide and 80 g of tungstic acid mixed in a solution of 1200 g of water and water for about 1 minute, dried at 150℃ for 3 hours, and then
Each catalyst was obtained by calcining at ℃ for 5 hours. Test Example 1 In order to examine the SOx resistance of the catalyst of the present invention obtained in Example 6, the catalyst was placed in the exhaust gas of a heavy oil-fired boiler containing 1000 to 1500 ppm of SOx and 20 to 30 ppm of SO3 .
As a result of a durability test conducted at 380℃, there was no abnormality after 5000 hours, and no strength loss or cracks were observed. On the other hand, as a comparative catalyst, a catalyst prepared from non-carbonated calcium silicate molded bodies according to Example 6 developed cracks and its strength was reduced to about 1/2. Further, the silica-calcium carbonate composite molded body obtained in Example 1 was immediately immersed in a slurry solution prepared by mixing 1000 g of titanium oxide and 80 g of tungstic acid in a solution of 20 g of vanadium pentoxide dissolved in 50 g of oxalic acid and 1200 g of water. Dry at 150℃ for 3 hours, then 550℃
For comparison purposes, a similar durability test was conducted on the catalyst obtained by firing for 5 hours. As a result, the adhesion of the catalyst component to the molded body was weak and peeling was observed. Table 1 shows changes in strength and appearance after the durability test.
【表】
試験例 2
実施例6で得られた触媒を石炭を燃料とするボ
イラ排ガス径路内に設置された脱硝装置の反応器
内に15mm間隔で排ガスと並行流になるように固定
設置した。この態様の一例を第1図に示す。これ
にNOxを含有するボイラ排ガスを流し、表2に
示す試験条件で触媒性能試験を実施し、脱硝性能
と同時に5000時間試験後の触媒の強度変化と熱歪
によるクラツク発生の有無をみた。第1図におい
て1は脱硝装置の反応器、2は排ガスの流れ方
向、3はアンモニア注入装置、4は本発明の脱硝
用触媒を示す。[Table] Test Example 2 The catalyst obtained in Example 6 was fixedly installed in a reactor of a denitrification device installed in the exhaust gas path of a coal-fired boiler at intervals of 15 mm so as to flow in parallel with the exhaust gas. An example of this embodiment is shown in FIG. Boiler exhaust gas containing NOx was flowed through this, and a catalyst performance test was conducted under the test conditions shown in Table 2. At the same time as the denitrification performance, changes in the strength of the catalyst after 5000 hours of testing and the occurrence of cracks due to thermal strain were observed. In FIG. 1, 1 is a reactor of a denitrification device, 2 is a flow direction of exhaust gas, 3 is an ammonia injection device, and 4 is a denitrification catalyst of the present invention.
【表】
脱硝性能については第2図、第3図に示す結果
を得、優れた触媒であることを確認した。第2図
は実施例6で得た本発明触媒を用いた場合の排ガ
ス中のNOxに対するNH3の添加量による脱硝率を
示したものである。又第3図は、第2図に関して
説明したと同じ触媒を用いて約5000時間試験した
場合の脱硝性能及び強度の経時変化を示したもの
で図中AはNH3〔ppm〕/NOx〔ppm〕=1.0での
脱硝率の変化を示し、B1は同触媒の曲げ強度の
変化、B2は従来の触媒、即ち、炭酸化しない珪
酸カルシウム成形体を実施例6に準じて調製した
触媒の曲げ強度変化を示したものである。又クラ
ツクの発生について観察した結果、本発明触媒は
何ら異常は認められなかつたが従来の比較触媒は
約3000時間で発生し、又触媒成分の剥離もみられ
た。
試験例 3
試験例2で5000時間試験した触媒について熱膨
脹収縮をみるためJRS2617の熱間線膨脹収縮率試
験法に準じて測定し、第4図、第5図に示す結果
を得た。
この結果本発明触媒は熱的変化が小さく、耐久
性において極めて優れることが確認された。
第4図は本発明触媒の熱間膨脹収縮曲線を示す
もので縦軸に膨脹率(%)を横軸に温度(℃)を
示す。図中においてaの曲線は試験前、a′の曲線
は5000時間試験後の値を示す。
又第5図は比較材としての従来の触媒の熱間膨
脹収縮曲線を示すもので、縦軸に膨脹率(%)を
横軸に温度(℃)を示す。bの曲線は試験前b′の
曲線は5000時間試験後の値を示したものである。[Table] Regarding the denitrification performance, the results shown in Figures 2 and 3 were obtained, and it was confirmed that the catalyst was excellent. FIG. 2 shows the denitrification rate depending on the amount of NH 3 added to NOx in the exhaust gas when the catalyst of the present invention obtained in Example 6 was used. Figure 3 shows the change in denitrification performance and strength over time when the same catalyst as explained in Figure 2 was tested for about 5000 hours. ] = 1.0, B 1 is the change in bending strength of the same catalyst, B 2 is the change in the conventional catalyst, that is, the catalyst prepared from non-carbonated calcium silicate molded bodies according to Example 6. It shows the change in bending strength. Further, as a result of observing the occurrence of cracks, no abnormality was observed in the catalyst of the present invention, but cracks occurred in the conventional comparative catalyst after about 3000 hours, and peeling of catalyst components was also observed. Test Example 3 In order to check the thermal expansion and contraction of the catalyst tested for 5000 hours in Test Example 2, it was measured according to the JRS2617 hot linear expansion and contraction rate test method, and the results shown in FIGS. 4 and 5 were obtained. As a result, it was confirmed that the catalyst of the present invention has small thermal changes and extremely excellent durability. FIG. 4 shows a hot expansion/contraction curve of the catalyst of the present invention, in which the vertical axis shows the expansion rate (%) and the horizontal axis shows the temperature (° C.). In the figure, the curve a shows the value before the test, and the curve a' shows the value after the 5000 hour test. FIG. 5 shows a hot expansion/contraction curve of a conventional catalyst as a comparison material, with the vertical axis showing the expansion rate (%) and the horizontal axis showing the temperature (°C). The curve b shows the value before the test, and the curve b' shows the value after the 5000 hour test.
第1図は、本発明による触媒を脱硝装置の反応
器内に設置した態様を示す図、第2図と第3図
は、本発明による触媒の性能を示すグラフ、第4
図は本発明による触媒の第5図は比較触媒の熱膨
脹試験の結果を示すグラフである。
1……脱硝装置、3……アンモニア注入装置、
4……脱硝用触媒。
FIG. 1 is a diagram showing an embodiment in which the catalyst according to the present invention is installed in a reactor of a denitration equipment, FIGS. 2 and 3 are graphs showing the performance of the catalyst according to the present invention, and FIG.
Figure 5 is a graph showing the results of a thermal expansion test of a catalyst according to the invention and Figure 5 is a comparative catalyst. 1... Denitrification device, 3... Ammonia injection device,
4... Catalyst for denitrification.
Claims (1)
させ、得られるシリカ−炭酸カルシウム複合成形
体を無水珪酸の超微粒子を水中に分散させたコロ
イド溶液に浸漬し、次いでチタン、バナジウム、
タングステンの酸化物を含有するスラリーに接触
後、乾燥、焼成することにより成る排ガス処理用
触媒の製造方法。1 A calcium silicate-based molded body is brought into contact with carbon dioxide, and the resulting silica-calcium carbonate composite molded body is immersed in a colloidal solution in which ultrafine particles of silicic anhydride are dispersed in water, and then titanium, vanadium,
A method for producing a catalyst for exhaust gas treatment, which comprises contacting a slurry containing tungsten oxide, drying and firing.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP8524379A JPS5610335A (en) | 1979-07-05 | 1979-07-05 | Manufacture of catalyst for disposing of waste gas |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP8524379A JPS5610335A (en) | 1979-07-05 | 1979-07-05 | Manufacture of catalyst for disposing of waste gas |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS5610335A JPS5610335A (en) | 1981-02-02 |
JPS6225417B2 true JPS6225417B2 (en) | 1987-06-03 |
Family
ID=13853115
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP8524379A Granted JPS5610335A (en) | 1979-07-05 | 1979-07-05 | Manufacture of catalyst for disposing of waste gas |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS5610335A (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2010079854A1 (en) * | 2009-01-08 | 2010-07-15 | 주식회사 엘지하우시스 | Catalyst for removing nitrogen oxides from exhaust gas, preparation method thereof, and method for removing nitrogen oxides from exhaust gas using the same |
-
1979
- 1979-07-05 JP JP8524379A patent/JPS5610335A/en active Granted
Also Published As
Publication number | Publication date |
---|---|
JPS5610335A (en) | 1981-02-02 |
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