JP4168230B2 - Dimethyl ether reforming catalyst and method for producing hydrogen-containing gas using the catalyst - Google Patents
Dimethyl ether reforming catalyst and method for producing hydrogen-containing gas using the catalyst Download PDFInfo
- Publication number
- JP4168230B2 JP4168230B2 JP2001354731A JP2001354731A JP4168230B2 JP 4168230 B2 JP4168230 B2 JP 4168230B2 JP 2001354731 A JP2001354731 A JP 2001354731A JP 2001354731 A JP2001354731 A JP 2001354731A JP 4168230 B2 JP4168230 B2 JP 4168230B2
- Authority
- JP
- Japan
- Prior art keywords
- catalyst
- dimethyl ether
- reaction
- zinc
- hydrogen
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- LCGLNKUTAGEVQW-UHFFFAOYSA-N Dimethyl ether Chemical compound COC LCGLNKUTAGEVQW-UHFFFAOYSA-N 0.000 title claims description 88
- 239000003054 catalyst Substances 0.000 title claims description 71
- 229910052739 hydrogen Inorganic materials 0.000 title claims description 25
- 239000001257 hydrogen Substances 0.000 title claims description 25
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 title claims description 24
- 239000007789 gas Substances 0.000 title claims description 22
- 238000004519 manufacturing process Methods 0.000 title claims description 17
- 238000002407 reforming Methods 0.000 title claims description 10
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 claims description 35
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 32
- 239000000203 mixture Substances 0.000 claims description 25
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 23
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims description 19
- 229910052763 palladium Inorganic materials 0.000 claims description 19
- 229910052725 zinc Inorganic materials 0.000 claims description 19
- 239000011701 zinc Substances 0.000 claims description 19
- 239000002243 precursor Substances 0.000 claims description 15
- 238000000034 method Methods 0.000 claims description 14
- 239000011651 chromium Substances 0.000 claims description 10
- 229910052804 chromium Inorganic materials 0.000 claims description 9
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims description 8
- 238000002156 mixing Methods 0.000 claims description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 2
- 239000001301 oxygen Substances 0.000 claims description 2
- 229910052760 oxygen Inorganic materials 0.000 claims description 2
- 238000006243 chemical reaction Methods 0.000 description 41
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 22
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 18
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 18
- 238000000629 steam reforming Methods 0.000 description 18
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 15
- 229910002091 carbon monoxide Inorganic materials 0.000 description 15
- 239000000843 powder Substances 0.000 description 12
- 239000011787 zinc oxide Substances 0.000 description 11
- 230000000052 comparative effect Effects 0.000 description 10
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 9
- 230000000694 effects Effects 0.000 description 9
- 239000002002 slurry Substances 0.000 description 9
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 7
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 7
- 150000003839 salts Chemical class 0.000 description 7
- 229910052802 copper Inorganic materials 0.000 description 6
- 239000010949 copper Substances 0.000 description 6
- 238000010438 heat treatment Methods 0.000 description 6
- 239000000243 solution Substances 0.000 description 6
- 239000007864 aqueous solution Substances 0.000 description 5
- 229910052878 cordierite Inorganic materials 0.000 description 5
- JSKIRARMQDRGJZ-UHFFFAOYSA-N dimagnesium dioxido-bis[(1-oxido-3-oxo-2,4,6,8,9-pentaoxa-1,3-disila-5,7-dialuminabicyclo[3.3.1]nonan-7-yl)oxy]silane Chemical compound [Mg++].[Mg++].[O-][Si]([O-])(O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2)O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2 JSKIRARMQDRGJZ-UHFFFAOYSA-N 0.000 description 5
- -1 naphtha Chemical class 0.000 description 5
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 5
- 230000001376 precipitating effect Effects 0.000 description 5
- 239000002994 raw material Substances 0.000 description 5
- PHFQLYPOURZARY-UHFFFAOYSA-N chromium trinitrate Chemical compound [Cr+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O PHFQLYPOURZARY-UHFFFAOYSA-N 0.000 description 4
- 150000002431 hydrogen Chemical class 0.000 description 4
- 238000011068 loading method Methods 0.000 description 4
- 238000003756 stirring Methods 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 239000006227 byproduct Substances 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 3
- 238000006477 desulfuration reaction Methods 0.000 description 3
- 230000023556 desulfurization Effects 0.000 description 3
- 239000000446 fuel Substances 0.000 description 3
- 238000005342 ion exchange Methods 0.000 description 3
- 150000007522 mineralic acids Chemical class 0.000 description 3
- 150000007524 organic acids Chemical class 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 229910052697 platinum Inorganic materials 0.000 description 3
- 239000002244 precipitate Substances 0.000 description 3
- 229910000029 sodium carbonate Inorganic materials 0.000 description 3
- 238000003786 synthesis reaction Methods 0.000 description 3
- 150000003752 zinc compounds Chemical class 0.000 description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- 239000012696 Pd precursors Substances 0.000 description 2
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 description 2
- UIIMBOGNXHQVGW-UHFFFAOYSA-M Sodium bicarbonate Chemical compound [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 description 2
- 238000001354 calcination Methods 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 150000001845 chromium compounds Chemical class 0.000 description 2
- DQIPXGFHRRCVHY-UHFFFAOYSA-N chromium zinc Chemical compound [Cr].[Zn] DQIPXGFHRRCVHY-UHFFFAOYSA-N 0.000 description 2
- 239000002131 composite material Substances 0.000 description 2
- 238000004817 gas chromatography Methods 0.000 description 2
- 238000000227 grinding Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 239000011268 mixed slurry Substances 0.000 description 2
- GPNDARIEYHPYAY-UHFFFAOYSA-N palladium(ii) nitrate Chemical compound [Pd+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O GPNDARIEYHPYAY-UHFFFAOYSA-N 0.000 description 2
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Chemical compound [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 description 2
- 238000006057 reforming reaction Methods 0.000 description 2
- 239000000725 suspension Substances 0.000 description 2
- JIAARYAFYJHUJI-UHFFFAOYSA-L zinc dichloride Chemical compound [Cl-].[Cl-].[Zn+2] JIAARYAFYJHUJI-UHFFFAOYSA-L 0.000 description 2
- ONDPHDOFVYQSGI-UHFFFAOYSA-N zinc nitrate Chemical compound [Zn+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O ONDPHDOFVYQSGI-UHFFFAOYSA-N 0.000 description 2
- 229910021555 Chromium Chloride Inorganic materials 0.000 description 1
- QPLDLSVMHZLSFG-UHFFFAOYSA-N Copper oxide Chemical compound [Cu]=O QPLDLSVMHZLSFG-UHFFFAOYSA-N 0.000 description 1
- 239000005751 Copper oxide Substances 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- WGLPBDUCMAPZCE-UHFFFAOYSA-N Trioxochromium Chemical compound O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 description 1
- 229910021536 Zeolite Inorganic materials 0.000 description 1
- ZOIORXHNWRGPMV-UHFFFAOYSA-N acetic acid;zinc Chemical compound [Zn].CC(O)=O.CC(O)=O ZOIORXHNWRGPMV-UHFFFAOYSA-N 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 239000000460 chlorine Substances 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- 229910000423 chromium oxide Inorganic materials 0.000 description 1
- QSWDMMVNRMROPK-UHFFFAOYSA-K chromium(3+) trichloride Chemical compound [Cl-].[Cl-].[Cl-].[Cr+3] QSWDMMVNRMROPK-UHFFFAOYSA-K 0.000 description 1
- WYYQVWLEPYFFLP-UHFFFAOYSA-K chromium(3+);triacetate Chemical compound [Cr+3].CC([O-])=O.CC([O-])=O.CC([O-])=O WYYQVWLEPYFFLP-UHFFFAOYSA-K 0.000 description 1
- GRWVQDDAKZFPFI-UHFFFAOYSA-H chromium(III) sulfate Chemical compound [Cr+3].[Cr+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O GRWVQDDAKZFPFI-UHFFFAOYSA-H 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 229910000431 copper oxide Inorganic materials 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000006297 dehydration reaction Methods 0.000 description 1
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 239000000706 filtrate Substances 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000006703 hydration reaction Methods 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 238000005984 hydrogenation reaction Methods 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 229910000510 noble metal Inorganic materials 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 1
- JUBNUQXDQDMSKL-UHFFFAOYSA-N palladium(2+);dinitrate;dihydrate Chemical compound O.O.[Pd+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O JUBNUQXDQDMSKL-UHFFFAOYSA-N 0.000 description 1
- PIBWKRNGBLPSSY-UHFFFAOYSA-L palladium(II) chloride Chemical compound Cl[Pd]Cl PIBWKRNGBLPSSY-UHFFFAOYSA-L 0.000 description 1
- YJVFFLUZDVXJQI-UHFFFAOYSA-L palladium(ii) acetate Chemical compound [Pd+2].CC([O-])=O.CC([O-])=O YJVFFLUZDVXJQI-UHFFFAOYSA-L 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 238000005504 petroleum refining Methods 0.000 description 1
- SKJKDBIPDZJBPK-UHFFFAOYSA-N platinum zinc Chemical compound [Zn].[Pt] SKJKDBIPDZJBPK-UHFFFAOYSA-N 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- 229910000027 potassium carbonate Inorganic materials 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 239000010970 precious metal Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 239000001294 propane Substances 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 229910000030 sodium bicarbonate Inorganic materials 0.000 description 1
- 235000017557 sodium bicarbonate Nutrition 0.000 description 1
- 239000011973 solid acid Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
- 239000010457 zeolite Substances 0.000 description 1
- 239000004246 zinc acetate Substances 0.000 description 1
- 239000011592 zinc chloride Substances 0.000 description 1
- 235000005074 zinc chloride Nutrition 0.000 description 1
- NWONKYPBYAMBJT-UHFFFAOYSA-L zinc sulfate Chemical compound [Zn+2].[O-]S([O-])(=O)=O NWONKYPBYAMBJT-UHFFFAOYSA-L 0.000 description 1
- 229910000368 zinc sulfate Inorganic materials 0.000 description 1
- 229960001763 zinc sulfate Drugs 0.000 description 1
- JGPSMWXKRPZZRG-UHFFFAOYSA-N zinc;dinitrate;hexahydrate Chemical compound O.O.O.O.O.O.[Zn+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O JGPSMWXKRPZZRG-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts
Description
【０００１】
【発明の属する技術分野】
本発明はジメチルエーテルの水蒸気改質による水素含有ガス製造法に関する。水素ガスはアンモニア合成、各種有機化合物の水素化、石油精製、脱硫等の化学工業用あるいは半導体や冶金の雰囲気ガス、ガラス製造等に広く使用されている。また、最近は自動車等の動力源となる燃料電池用の原料としても注目され、今後も水素ガス需要の大幅な拡大が期待されている。
【０００２】
【従来の技術】
水素ガスの製造法としては、例えば、ナフサ、天然ガスや石油液化ガス等の炭化水素類の水蒸気改質法が知られている。この方法は原料の脱硫が必要なこと、反応温度が８００〜１０００℃で非常に高いこと等の欠点を有する。
また、メタノールを原料とした水蒸気改質法もよく知られており、脱硫が不要で反応温度が低い等の利点を有し、近年注目され、小規模から大規模までの設備が多数設置されている。
【０００３】
一方、その他の水蒸気改質法による水素製造法ではジメチルエーテルを原料とする方法が挙げられる。ジメチルエーテルはクリーンな燃料として自動車および発電用途として期待されており、常温において約２気圧程度で容易に液化するため、貯蔵や運搬等液化プロパンガスと同等の取り扱いが可能である。
ジメチルエーテルは現在、メタノールの脱水反応によって製造されており、高価ではあるが、合成ガスからの直接合成法が開発されるに至って安価に、かつ、大量に供給できる可能性が生じている。
【０００４】
ジメチルエーテルの水蒸気改質反応は（１）式でおよび（２）式の２段反応で進行するものと考えられている。
ＣＨ3ＯＣＨ3＋ Ｈ2Ｏ ＝ ２ＣＨ3ＯＨ ＋23.5kJ/mol （１）
ＣＨ3ＯＨ ＋ Ｈ2Ｏ ＝ ＣＯ2 ＋ ３Ｈ2＋49.5kJ/mol （２）
また、上記の主反応の他に（３）式の逆シフト反応や（４）式のメタネーション反応などにより少量の一酸化炭素やメタンが副生する。
ＣＯ2 ＋ Ｈ2＝ ＣＯ ＋ Ｈ2Ｏ ＋41.17kJ/mol（３）
ＣＯ + ３Ｈ2＝ ＣＨ4＋ Ｈ2Ｏ - 206.2kJ/mol（４）
【０００５】
これらの反応により副生した一酸化炭素やメタンは高純度水素に精製する際に除去しにくく、極力少ない方が好ましい。熱力学平衡から、低温ほど、また水蒸気とジメチルエーテルのモル比（以下、Ｓ／Ｄ比）が大きいほど改質ガス中の副生物濃度を低くさせることができる。
ジメチルエーテルの水蒸気改質反応は（２）式のみのメタノール改質反応に比べて化学量論上は２倍量の水素を生成させることが可能であるが、（１）式の水和反応が吸熱反応であるため、より高温での反応条件が必要である。従って、より低温においても高活性を有する触媒であれば、外熱供給システムを小型化することが可能となり、熱効率も上がる。
【０００６】
一方、ジメチルエーテルと水蒸気と共に空気を導入してジメチルエーテルの一部を酸化し、その熱を利用して（１）および（２）式の主反応である吸熱反応を起こさせる自己熱供給型反応がある。この方法はジメチルエーテルの一部を（５）式に示すように水素と二酸化炭素に酸化し、この熱を利用して（１）および（２）式の主反応を行うものである。
ＣＨ3ＯＣＨ3＋ ３／２Ｏ2 ＝ ３Ｈ2 ＋ ２ＣＯ2 -603.7kJ/mol（５）
この方法によれば反応開始時に必要な温度レベルにまで昇温する熱以外は、反応が継続されると熱の供給を必要としない特徴を有する。
【０００７】
ジメチルエーテルの水蒸気改質反応に使用される触媒には、例えば銅系触媒として、銅、亜鉛、アルミニウムの酸化物を含有する触媒（米国特許5,498,370号公報参照）、銅、亜鉛、アルミニウムの酸化物を含有する触媒とゼオライトやシリカ−アルミナの混合触媒（特開平9-118501号公報参照）等が提案されている。
また、貴金属を用いた触媒も種々報告されており、例えば、酸化亜鉛にパラジウムを含浸させたもの（特開平10-174865号公報参照）、酸化亜鉛に白金を含浸させたもの（特開2000-320407号公報参照）等がある。
【０００８】
【発明が解決しようとする課題】
ジメチルエーテルを水蒸気改質し、水素を製造する場合には、一般に３５０〜４５０℃の反応温度が必要であり、エネルギーコストを考えた場合、より低温での熱供給に対して高活性を示す触媒が求められる。
また、自己熱供給型反応においては反応開始時のみの熱供給で済むことから非常に有利である。しかしながら、ジメチルエーテルと水蒸気および空気を反応させて水素を製造する自己熱供給型反応では、ジメチルエーテルの一部を酸化させるために、反応が起こっている近傍は水蒸気改質反応と比較してはるかに高い温度となる。従って、自己熱供給型反応の触媒には高い耐熱性が求められる。また、自動車等の動力源となる燃料電池用に水素を製造する場合には、搭載容量等に制限があるために、改質反応器を小型化することが必要であり、ガス空間速度（以下、ＧＨＳＶとする）が高い場合においても、より活性の高い触媒が求められる。
【０００９】
前述のように、ジメチルエーテルと水蒸気を原料とするジメチルエーテルの水蒸気改質触媒として種々の触媒が提案されている。しかしながら、従来知られているジメチルエーテルの水蒸気改質触媒では耐熱性や活性が十分でなく、そのまま自己熱供給型反応に使用することができない。例えば、銅、亜鉛の酸化物触媒と固体酸触媒をある粒径で物理混合する触媒は自己熱供給型反応のジメチルエーテル水蒸気改質反応に使用することができるが、この場合、反応熱により触媒成分である銅、亜鉛のシンタリングや触媒粒子の粉化等により、短時間でその活性が低下する。
耐熱性を高めるためにアルミニウム酸化物を添加した銅、亜鉛、アルミニウム系触媒が知られているが、この触媒も自己熱供給型反応には十分でない。
また、酸化亜鉛と白金またはパラジウム等の貴金属触媒系では、水素と一酸化炭素からなる合成ガスの製造法には使用できるが、その他、メタン等の副生物も多く、一酸化炭素、メタン濃度が低い水素含有ガスを製造する本発明の目的にはそぐわない。
本発明の目的はジメチルエーテルの水蒸気改質において、高活性を有する触媒を開発し、小型装置にて容易に低一酸化炭素、あるいは低メタン濃度の水素含有ガスを製造する方法を提供することである。さらには、空気を導入した自己熱供給型反応においても好適な方法を提供することである。
【００１０】
【課題を解決するための手段】
本発明者らはジメチルエーテルの水蒸気改質により水素含有ガスを製造する方法における上記課題について鋭意研究した結果、特定の方法で調製した触媒が高活性を有し、しかも耐熱性も有することから自己熱供給型反応にも好適であることを見い出し、本発明に到達した。
すなわち、本発明は、亜鉛およびパラジウムを含有する前駆体混合物に活性アルミナを混合して調製することを特徴とするジメチルエーテル改質触媒の製造方法、および同方法で調製された触媒を使用した水素含有ガス製造方法に関するものである。
【００１１】
【発明の実施の形態】
本発明の触媒は亜鉛およびパラジウムを含有する前駆体混合物と活性アルミナを混合して調製する。この前駆体混合物は更にクロムを含有してもよい。
前駆体混合物の亜鉛源およびクロム源としては、水溶性の亜鉛化合物およびクロム化合物が用いられ、該化合物の水溶液を沈殿剤で処理して得られた沈殿物を焼成したときに酸化物に変化し得る化合物が用いられる。
亜鉛化合物としては、例えば酢酸亜鉛等の有機酸の水溶性塩、あるいは塩化亜鉛、硫酸亜鉛、硝酸亜鉛等の無機酸の水溶性塩や酸化亜鉛等が使用できる。
クロム化合物としては、例えば酢酸クロム等の有機酸の水溶性塩、あるいは塩化クロム、硫酸クロム、硝酸クロム等の無機酸の水溶性塩や酸化クロム等が使用できる。
パラジウム源としては、例えば酢酸パラジウム等の有機酸の水溶性塩、あるいは塩化パラジウム、硝酸パラジウム等の無機酸の水溶性塩等が使用できる。
【００１２】
亜鉛およびパラジウムを含有する前駆体混合物は、亜鉛化合物にパラジウムを析出沈殿させる、あるいは亜鉛とパラジウムを共沈殿させることにより調製することができる。
亜鉛、クロムおよびパラジウムを含有する前駆体混合物は、亜鉛とクロムを主成分とする組成物にパラジウムを析出沈殿あるいは共沈殿させることで調製できる。
これらの金属塩の水溶液に沈殿剤を作用させることにより、当該金属を含有する沈殿物を得ることができる。
沈殿剤には、水酸化ナトリウム、水酸化カリウム、炭酸ナトリウム、炭酸カリウム、炭酸水素ナトリウム等の水溶性アルカリ化合物が用いられる。
【００１３】
本発明の亜鉛およびパラジウムを含有する前駆体混合物の組成はパラジウム／亜鉛の原子比で０．００４〜２．２、好ましくは０．０４〜０．６である。
また、亜鉛、クロムおよびパラジウムを含有する前駆体混合物の組成は亜鉛／クロムの原子比で０．５〜３０、好ましくは１〜２０、パラジウム／亜鉛の原子比で０．００４〜２．２、好ましくは０．０４〜０．６である。
【００１４】
前駆体混合物である沈殿物は、乾燥し、焼成する。乾燥温度は５０〜１５０℃で、焼成は空気中１８０℃〜５００℃、好ましくは２００〜４００℃で行われる。
【００１５】
このようにして得られた乾燥粉あるいは焼成粉は粉砕し、活性アルミナの粉末とよく混合させる。活性アルミナと乾燥粉とを混合した場合はその後、焼成する。また、混合スラリーと活性アルミナを混合後、乾燥および焼成してもよい。
本発明では、各種の活性アルミナを使用できるが、γ−アルミナ、δ−アルミナ、θ−アルミナが好ましく、γ−アルミナが特に好ましい。
活性アルミナの混合比は乾燥粉あるいは焼成粉に対し、活性アルミナが体積比で１／３〜２、好ましくは１／５〜３／２の割合である。混合スラリーの場合も前記に準ずる。
【００１６】
このようにして得られた活性アルミナ混合物は大きさを揃えて錠剤成型し、粒径を揃えて粉砕する等して、使用することができる。また、活性アルミナと乾燥粉とを混合したものを水に懸濁させ、必要に応じてアルミナゾルのようなバインダーを添加して、担体や担体構造物に担持することができる。担持後、乾燥してそのまま、あるいは焼成後使用することができる。活性アルミナと焼成粉とを混合したものについても同様に担体や担体構造物に担持することができ、担持後、乾燥してそのまま、あるいは焼成後使用することができる。
【００１７】
触媒の使用にあたってはジメチルエーテルと水蒸気を反応させる水蒸気改質反応、あるいは空気を導入し、ジメチルエーテルと水蒸気および酸素を反応させる自己熱供給型反応のいずれの場合も、水素や一酸化炭素含有ガスによって活性化処理を行っても良いし、活性化処理をすることなく、反応に供することもできる。
【００１８】
ジメチルエーテルと水蒸気を反応させる水蒸気改質反応あるいは空気を導入する自己熱供給型反応では水蒸気／ジメチルエーテル比（Ｓ／Ｄ）は３〜１０、好ましくは３〜６である。空気を導入する場合には、空気／ジメチルエーテル比（Ａ／Ｄ）は０．５〜１０、好ましくは、１．５〜５であり、ジメチルエーテルの爆発範囲を避け、燃焼反応による発熱と水蒸気改質反応による吸熱がバランスするような条件が選定される。
【００１９】
反応温度は１５０〜６００℃、好ましくは２００〜５００℃で、圧力は常圧が好ましい。単位触媒当たりの水蒸気およびジメチルエーテルのガス空間速度（ＧＨＳＶ）は、空気を共存させない水蒸気改質反応では３００〜８０００ｈ-1、好ましくは５００〜５０００ｈ-1であり、自己熱供給型反応では３００〜１０００００ｈ-1、好ましくは１０００〜２５０００ｈ-1である。
【００２０】
【実施例】
以下に実施例、比較例により本発明をさらに詳しく説明するが、本発明はこれらの実施例により制限されるものではない。
【００２１】
＜触媒の調製＞
実施例１
酸化亜鉛１５ｇをイオン交換水５００ｍｌに分散させ、３５℃とした。ここに硝酸パラジウム２水和物４．１７ｇをイオン交換水５００ｍｌに溶解させて、３５℃とした溶液を前述の懸濁液へ撹拌しながら、注加し、さらに、１Ｎ水酸化カリウム水溶液を３５ｍｌ加えた後、１時間撹拌を続けた。このようにして得られたスラリーを濾過し、イオン交換水４リットルで洗浄した。続いて８０℃で乾燥し、その後、３８０℃にて２時間焼成することにより亜鉛−パラジウム前駆体混合物（10重量％Pd/ZnO）を得た。この焼成粉２ｇに市販のγ−アルミナ（比表面積２３０ｍ2／ｇ）を３．３ｇ加え、イオン交換水で湿式粉砕し、得られたスラリーを４００セル／平方インチのコージェライトハニカムへ約２００ｇ／Ｌ担持して、触媒Ａを得た。
【００２２】
実施例２
炭酸ナトリウム（無水）１３８ｇを１０００ｍｌのイオン交換水と共に５リットルの丸底フラスコに入れ溶解し、６０℃とした。ここに硝酸亜鉛（６水塩）２３８ｇ、硝酸クロム８０ｇをイオン交換水８００ｍｌに溶解し、６０℃とした溶液を前述の炭酸ナトリウム溶液へ注加し、３０分撹拌した。このようにして得たスラリーを濾過し、イオン交換水１２リットルで洗浄した。続いて８０℃で乾燥し、その後、３８０℃にて２時間焼成することにより、亜鉛−クロム複合酸化物を得た。
前述の亜鉛−クロム複合酸化物１００ｇを１０００ｍｌのイオン交換水と共に５リットルの丸底フラスコに入れ、撹拌し、４０℃とした。ここに硝酸パラジウム（１．９水塩）２６ｇをイオン交換水２０００ｍｌに溶解し、４０℃に調節した溶液を注加し、続いて２０重量％炭酸ナトリウム水溶液５０ｍｌを加え、３０分撹拌した。このように調製したスラリーを濾過し、イオン交換水１２リットルで洗浄した。続いて８０℃で乾燥し、その後、３８０℃にて２時間焼成することにより、パラジウム−亜鉛−クロム前駆体混合物（10重量％Pd/ZnO-Cr2O3）を得た。
この焼成粉２ｇに市販のγ−アルミナ（比表面積２３０ｍ2／ｇ）を３．３ｇ加え、イオン交換水で湿式粉砕し、得られたスラリーを４００セル／平方インチのコージェライトハニカムへ約２００ｇ／Ｌ担持して、触媒Ｂを得た。
【００２３】
比較例１
市販の銅、亜鉛系触媒（CuO 30重量％、ZnO 70重量％）の円柱状成型品２ｇを粉砕し、市販のγ−アルミナ（比表面積２３０ｍ2／ｇ）を１．６ｇ加え、イオン交換水を用い、湿式粉砕した。得られたスラリーを４００セル／平方インチのコージェライトハニカムへ約２００ｇ／Ｌ担持して、触媒Ｃを得た。
【００２４】
比較例２
酸化亜鉛１５ｇをイオン交換水５００ｍｌに分散させ、６０℃とした。ここに塩化白金酸カリウム３．５４ｇをイオン交換水５００ｍｌに溶解させて、６０℃とした溶液を前述の懸濁液へ撹拌しながら、注加し、さらに、１Ｎ水酸化カリウム水溶液を１７ｍｌ加えた後、１時間撹拌を続けた。このようにして得られたスラリーを濾過し、濾液中の塩素イオンが１〜３ppm以下になるまで洗浄した。続いて８０℃で乾燥し、その後、３８０℃にて２時間焼成することにより亜鉛−白金前駆体混合物(10重量％Pt/ZnO)を得た。この焼成粉２ｇに市販のγ−アルミナ（比表面積２３０ｍ2／ｇ）を３．３ｇ加え、イオン交換水で湿式粉砕し、得られたスラリーを４００セル／平方インチのコージェライトハニカムへ約２００ｇ／Ｌ担持して、触媒Ｄを得た。
【００２５】
比較例３
実施例１に記載の方法に従い、亜鉛−パラジウム前駆体混合物(10重量%Pd/ZnO)を得た。この焼成粉２ｇはγ−アルミナを加えず、イオン交換水で湿式粉砕し、得られたスラリーを４００セル／平方インチのコージェライトハニカムへ約２００ｇ／Ｌ担持して、触媒Ｅを得た。
【００２６】
＜水素の製造＞
実施例３
固定床流通反応装置の反応管に触媒Ａ（ハニカムの有効体積３．７３ｍｌ）を充填し、常圧、触媒層への入口ガス温度を２７５℃となるようにして、スチーム／ジメチルエーテル比（Ｓ／Ｄ）５／１、ＧＨＳＶ３３２０ｈ-1で触媒の活性を評価した。反応後のガスはガスクロマトグラフィーにより分析した。水素、一酸化炭素（ＣＯ）、メタン、残存DME、残存メタノール濃度、DME反応率を表１に示す。触媒層温度はハニカム上部より２mmの位置の温度を示す。
【００２７】
実施例４
触媒Ａの代わりに触媒Ｂを用いた以外は実施例３と同様とした。
【００２８】
比較例４
触媒Ａの代わりに触媒Ｃを用いた以外は実施例３と同様とした。
【００２９】
比較例５
触媒Ａの代わりに触媒Ｄを用いた以外は実施例３と同様とした。
【００３０】
比較例６
触媒Ａの代わりに触媒Ｅを用いた以外は実施例３と同様とした。
【００３１】
実施例５
固定床流通反応装置の反応管に触媒Ａ（ハニカムの有効体積３．７３ｍｌ）を充填し、常圧、触媒層への入口ガス温度を２９０℃となるようにして、スチーム／ジメチルエーテル比（Ｓ／Ｄ）５／１、ＧＨＳＶ３３２０ｈ-1、空気を空気／ジメチルエーテル比（Ａ／Ｄ）２．５３〜３．１５、総ＧＨＳＶ５０７０〜５４００ｈ-1で導入し、自己熱供給型反応における触媒の活性を評価した。反応後のガスはガスクロマトグラフィーにより分析した。水素、一酸化炭素（ＣＯ）、メタン、残存DME、残存メタノール濃度、DME反応率を表２に示す。触媒層温度はハニカム上部より２mmの位置の温度を示す。
【００３３】
実施例６
触媒Ａの代わりに触媒Ｂを用いた以外は実施例５と同様とした。
【００３４】
比較例７
触媒Ａの代わりに触媒Ｃを用いた以外は実施例５と同様とした。
【００３５】
比較例８
触媒Ａの代わりに触媒Ｄを用いた以外は実施例５と同様とした。
【００３６】
比較例９
触媒Ａの代わりに触媒Ｅを用いた以外は実施例５と同様とした。
【００３７】
【発明の効果】
以上の実施例からも明らかなように、本発明による触媒は、ジメチルエーテルを水蒸気と反応させて水素を主成分とする改質反応を行う際に、あるいは空気を導入する自己熱供給型反応を行う際に、高い水素濃度を維持し、一酸化炭素やメタン、あるいは残存メタノール等の副生成物が極めて少ない混合ガスが得られる。すなわち、このジメチルエーテル改質触媒を用いれば、小型装置で容易に水素濃度の高い混合ガスを製造することができる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a hydrogen-containing gas by steam reforming of dimethyl ether. Hydrogen gas is widely used for chemical industry such as ammonia synthesis, hydrogenation of various organic compounds, petroleum refining, desulfurization, etc., semiconductor or metallurgical atmosphere gas, glass production and the like. Recently, it has been attracting attention as a raw material for fuel cells that serve as a power source for automobiles and the like, and the demand for hydrogen gas is expected to greatly increase in the future.
[0002]
[Prior art]
As a method for producing hydrogen gas, for example, a steam reforming method of hydrocarbons such as naphtha, natural gas, and petroleum liquefied gas is known. This method has drawbacks such as the need for desulfurization of the raw material and a very high reaction temperature of 800 to 1000 ° C.
In addition, the steam reforming method using methanol as a raw material is well known and has advantages such as no desulfurization and low reaction temperature. It has attracted attention in recent years and many facilities from small to large are installed. Yes.
[0003]
On the other hand, other hydrogen production methods by steam reforming include a method using dimethyl ether as a raw material. Dimethyl ether is expected to be used as a clean fuel for automobiles and power generation, and is easily liquefied at about 2 atm at room temperature. Therefore, it can be handled in the same manner as liquefied propane gas for storage and transportation.
Dimethyl ether is currently produced by a dehydration reaction of methanol and is expensive. However, since a direct synthesis method from synthesis gas has been developed, there is a possibility that it can be supplied in a large amount at a low cost.
[0004]
It is considered that the steam reforming reaction of dimethyl ether proceeds by the two-stage reaction of formula (1) and formula (2).
CH 3 OCH 3 + H 2 O = 2CH 3 OH + 23.5 kJ / mol (1)
CH 3 OH + H 2 O = CO 2 + 3H 2 +49.5 kJ / mol (2)
In addition to the main reaction described above, a small amount of carbon monoxide and methane are by-produced by the reverse shift reaction of the formula (3) and the methanation reaction of the formula (4).
CO 2 + H 2 = CO + H 2 O + 41.17 kJ / mol (3)
CO + 3H 2 = CH 4 + H 2 O-206.2 kJ / mol (4)
[0005]
Carbon monoxide and methane by-produced by these reactions are difficult to remove when purifying to high-purity hydrogen, and it is preferable that the amount be as small as possible. From the thermodynamic equilibrium, the by-product concentration in the reformed gas can be lowered as the temperature is lower and as the molar ratio of water vapor to dimethyl ether (hereinafter, S / D ratio) is larger.
The steam reforming reaction of dimethyl ether can generate stoichiometrically twice as much hydrogen as the methanol reforming reaction using only formula (2), but the hydration reaction of formula (1) is endothermic. Since it is a reaction, reaction conditions at higher temperatures are required. Therefore, if the catalyst has high activity even at a lower temperature, the external heat supply system can be reduced in size, and the thermal efficiency is improved.
[0006]
On the other hand, there is a self-heat supply type reaction in which air is introduced together with dimethyl ether and water vapor to oxidize part of the dimethyl ether and use the heat to cause an endothermic reaction which is the main reaction of the formulas (1) and (2) . In this method, a part of dimethyl ether is oxidized to hydrogen and carbon dioxide as shown in formula (5), and the main reaction of formulas (1) and (2) is performed using this heat.
CH 3 OCH 3 + 3 / 2O 2 = 3H 2 + 2CO 2 -603.7 kJ / mol (5)
According to this method, the heat does not need to be supplied when the reaction is continued, except for the heat raised to the temperature level required at the start of the reaction.
[0007]
Examples of the catalyst used in the steam reforming reaction of dimethyl ether include, as a copper catalyst, a catalyst containing copper, zinc and aluminum oxides (see US Pat. No. 5,498,370), copper, zinc and aluminum oxides. A catalyst containing the catalyst and a mixed catalyst of zeolite or silica-alumina (see JP-A-9-185501) have been proposed.
Various catalysts using noble metals have also been reported, for example, zinc oxide impregnated with palladium (see JP-A-10-174865), zinc oxide impregnated with platinum (JP-A-2000-2000) 320407).
[0008]
[Problems to be solved by the invention]
When hydrogen is produced by steam reforming dimethyl ether, a reaction temperature of 350 to 450 ° C. is generally required, and considering energy costs, a catalyst exhibiting high activity with respect to heat supply at a lower temperature is used. Desired.
In addition, the self-heat supply type reaction is very advantageous because it only requires heat supply at the start of the reaction. However, in the self-heating type reaction in which dimethyl ether reacts with steam and air to produce hydrogen, in order to oxidize a part of dimethyl ether, the vicinity where the reaction occurs is much higher than the steam reforming reaction It becomes temperature. Therefore, high heat resistance is required for the catalyst of the self-heat supply type reaction. In addition, when producing hydrogen for a fuel cell as a power source for an automobile or the like, it is necessary to downsize the reforming reactor due to a limitation in the mounting capacity, etc. , GHSV) is high, a more active catalyst is required.
[0009]
As described above, various catalysts have been proposed as dimethyl ether steam reforming catalysts using dimethyl ether and steam as raw materials. However, conventionally known dimethyl ether steam reforming catalysts are insufficient in heat resistance and activity, and cannot be used as they are in a self-heat supply type reaction. For example, a catalyst in which copper and zinc oxide catalysts and solid acid catalysts are physically mixed with a certain particle size can be used for a dimethyl ether steam reforming reaction of a self-heating supply type reaction. The activity decreases in a short time due to sintering of copper and zinc or powdering of catalyst particles.
Copper, zinc, and aluminum-based catalysts with aluminum oxide added to increase heat resistance are known, but these catalysts are also not sufficient for self-heated reactions.
In addition, in precious metal catalyst systems such as zinc oxide and platinum or palladium, it can be used for the production of synthesis gas consisting of hydrogen and carbon monoxide, but there are many other by-products such as methane, and the concentration of carbon monoxide and methane is low. It is not suitable for the purposes of the present invention to produce a low hydrogen-containing gas.
An object of the present invention is to develop a catalyst having high activity in steam reforming of dimethyl ether, and to provide a method for easily producing a hydrogen-containing gas having a low carbon monoxide or a low methane concentration in a small apparatus. . Furthermore, the present invention provides a suitable method even in a self-heat supply type reaction in which air is introduced.
[0010]
[Means for Solving the Problems]
As a result of diligent research on the above-mentioned problems in the method for producing a hydrogen-containing gas by steam reforming of dimethyl ether, the present inventors have found that a catalyst prepared by a specific method has high activity and also has heat resistance. It has been found that it is suitable for a feed-type reaction, and has reached the present invention.
That is, the present invention provides a method for producing a dimethyl ether reforming catalyst, which is prepared by mixing activated alumina with a precursor mixture containing zinc and palladium, and hydrogen containing using the catalyst prepared by the method The present invention relates to a gas manufacturing method.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The catalyst of the present invention is prepared by mixing a precursor mixture containing zinc and palladium and activated alumina. This precursor mixture may further contain chromium.
As the zinc source and chromium source of the precursor mixture, a water-soluble zinc compound and chromium compound are used. When the precipitate obtained by treating an aqueous solution of the compound with a precipitating agent is calcined, it changes into an oxide. The resulting compound is used.
As the zinc compound, for example, a water-soluble salt of an organic acid such as zinc acetate, a water-soluble salt of an inorganic acid such as zinc chloride, zinc sulfate, or zinc nitrate, or zinc oxide can be used.
As the chromium compound, for example, a water-soluble salt of an organic acid such as chromium acetate, a water-soluble salt of an inorganic acid such as chromium chloride, chromium sulfate, or chromium nitrate, or chromium oxide can be used.
As the palladium source, for example, a water-soluble salt of an organic acid such as palladium acetate, or a water-soluble salt of an inorganic acid such as palladium chloride or palladium nitrate can be used.
[0012]
The precursor mixture containing zinc and palladium can be prepared by precipitating and precipitating palladium on a zinc compound or by coprecipitating zinc and palladium.
A precursor mixture containing zinc, chromium and palladium can be prepared by precipitating or co-precipitating palladium in a composition containing zinc and chromium as main components.
By allowing a precipitant to act on the aqueous solution of these metal salts, a precipitate containing the metal can be obtained.
As the precipitating agent, a water-soluble alkaline compound such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium hydrogen carbonate or the like is used.
[0013]
The composition of the precursor mixture containing zinc and palladium of the present invention is 0.004 to 2.2, preferably 0.04 to 0.6, in terms of palladium / zinc atomic ratio.
The composition of the precursor mixture containing zinc, chromium and palladium is 0.5 to 30, preferably 1 to 20 in terms of zinc / chromium, and 0.004 to 2.2 in terms of palladium / zinc. Preferably it is 0.04-0.6.
[0014]
The precipitate which is the precursor mixture is dried and fired. The drying temperature is 50 to 150 ° C., and the calcination is performed in air at 180 to 500 ° C., preferably 200 to 400 ° C.
[0015]
The dry powder or calcined powder thus obtained is pulverized and mixed well with activated alumina powder. When the activated alumina and the dry powder are mixed, they are then fired. Further, the mixed slurry and activated alumina may be mixed and then dried and fired.
In the present invention, various activated aluminas can be used, but γ-alumina, δ-alumina and θ-alumina are preferable, and γ-alumina is particularly preferable.
The mixing ratio of the activated alumina is 1/3 to 2, preferably 1/5 to 3/2, by volume of the activated alumina with respect to the dry powder or fired powder. The same applies to the case of mixed slurry.
[0016]
The activated alumina mixture thus obtained can be used by making tablets with the same size and grinding with the same particle size. In addition, a mixture of activated alumina and dry powder can be suspended in water, and a binder such as alumina sol can be added as necessary, and supported on a carrier or a carrier structure. After loading, it can be dried and used as it is or after firing. A mixture of activated alumina and calcined powder can also be supported on a support or a support structure in the same manner, and can be used as it is after it is supported or dried or used after calcining.
[0017]
The catalyst is activated by hydrogen or carbon monoxide-containing gas in either the steam reforming reaction in which dimethyl ether reacts with steam or the self-heating supply reaction in which air is introduced and dimethyl ether reacts with steam and oxygen. The treatment may be performed, or the reaction can be performed without performing the activation treatment.
[0018]
In a steam reforming reaction in which dimethyl ether and steam are reacted or in a self-heating supply reaction in which air is introduced, the steam / dimethyl ether ratio (S / D) is 3 to 10, preferably 3 to 6. When air is introduced, the air / dimethyl ether ratio (A / D) is 0.5 to 10, preferably 1.5 to 5, avoiding the explosion range of dimethyl ether, exothermic and steam reforming by combustion reaction Conditions are selected that balance the endothermic reaction.
[0019]
The reaction temperature is 150 to 600 ° C, preferably 200 to 500 ° C, and the pressure is preferably atmospheric pressure. Units gas space velocity of water vapor and dimethyl ether per catalyst (GHSV) is, 300～8000H -1 in steam reforming not coexist air reaction, preferably 500~5000h -1, 300~100000h is a self heat supply type reaction −1 , preferably 1000 to 25000 h −1 .
[0020]
【Example】
The present invention will be described in more detail with reference to the following examples and comparative examples, but the present invention is not limited to these examples.
[0021]
<Preparation of catalyst>
Example 1
15 g of zinc oxide was dispersed in 500 ml of ion-exchanged water and the temperature was 35 ° C. Here, 4.17 g of palladium nitrate dihydrate was dissolved in 500 ml of ion-exchanged water, and the solution adjusted to 35 ° C. was added to the above suspension while stirring. Further, 35 ml of 1N potassium hydroxide aqueous solution was added. After the addition, stirring was continued for 1 hour. The slurry thus obtained was filtered and washed with 4 liters of ion exchange water. Subsequently, it was dried at 80 ° C. and then calcined at 380 ° C. for 2 hours to obtain a zinc-palladium precursor mixture (10 wt% Pd / ZnO). 3.3 g of commercially available γ-alumina (specific surface area 230 m 2 / g) was added to 2 g of this calcined powder, wet-pulverized with ion-exchanged water, and the resulting slurry was applied to a cordierite honeycomb of 400 cells / square inch at about 200 g / Catalyst A was obtained by loading L.
[0022]
Example 2
138 g of sodium carbonate (anhydrous) was dissolved in a 5-liter round bottom flask together with 1000 ml of ion-exchanged water, and the temperature was adjusted to 60 ° C. Here, 238 g of zinc nitrate (hexahydrate) and 80 g of chromium nitrate were dissolved in 800 ml of ion-exchanged water, and a solution adjusted to 60 ° C. was poured into the sodium carbonate solution described above and stirred for 30 minutes. The slurry thus obtained was filtered and washed with 12 liters of ion exchange water. Subsequently, it was dried at 80 ° C., and then fired at 380 ° C. for 2 hours to obtain a zinc-chromium composite oxide.
100 g of the aforementioned zinc-chromium composite oxide was placed in a 5-liter round bottom flask together with 1000 ml of ion-exchanged water and stirred to 40 ° C. To this, 26 g of palladium nitrate (1.9 hydrate) was dissolved in 2000 ml of ion-exchanged water, and a solution adjusted to 40 ° C. was added. Subsequently, 50 ml of 20 wt% sodium carbonate aqueous solution was added and stirred for 30 minutes. The slurry thus prepared was filtered and washed with 12 liters of ion exchange water. Subsequently, it was dried at 80 ° C., and then calcined at 380 ° C. for 2 hours to obtain a palladium-zinc-chromium precursor mixture (10 wt% Pd / ZnO—Cr 2 O 3).
3.3 g of commercially available γ-alumina (specific surface area 230 m 2 / g) was added to 2 g of this calcined powder, and wet-pulverized with ion-exchanged water. The resulting slurry was applied to a cordierite honeycomb of 400 cells / square inch at about 200 g / Catalyst B was obtained by loading L.
[0023]
Comparative Example 1
Crush 2g of a columnar molded product of commercially available copper and zinc-based catalyst (CuO 30% by weight, ZnO 70% by weight), add 1.6g of commercially available γ-alumina (specific surface area 230m 2 / g), and ion-exchanged water. Was used and wet pulverized. The obtained slurry was supported on a cordierite honeycomb of 400 cells / square inch at about 200 g / L to obtain Catalyst C.
[0024]
Comparative Example 2
15 g of zinc oxide was dispersed in 500 ml of ion-exchanged water, and the temperature was 60 ° C. A solution prepared by dissolving 3.54 g of potassium chloroplatinate in 500 ml of ion-exchanged water and adding the solution to 60 ° C. while stirring was added to the above suspension, and 17 ml of 1N potassium hydroxide aqueous solution was further added. Thereafter, stirring was continued for 1 hour. The slurry thus obtained was filtered and washed until the chlorine ions in the filtrate were 1 to 3 ppm or less. Subsequently, it was dried at 80 ° C. and then calcined at 380 ° C. for 2 hours to obtain a zinc-platinum precursor mixture (10 wt% Pt / ZnO). 3.3 g of commercially available γ-alumina (specific surface area 230 m 2 / g) was added to 2 g of this calcined powder, and wet-pulverized with ion-exchanged water. The resulting slurry was applied to a cordierite honeycomb of 400 cells / square inch at about 200 g / Catalyst D was obtained by loading L.
[0025]
Comparative Example 3
According to the method described in Example 1, a zinc-palladium precursor mixture (10 wt% Pd / ZnO) was obtained. 2 g of this calcined powder was wet pulverized with ion-exchanged water without adding γ-alumina, and the resulting slurry was supported on a cordierite honeycomb of 400 cells / in 2 for about 200 g / L to obtain Catalyst E.
[0026]
<Production of hydrogen>
Example 3
The reaction tube of the fixed bed flow reactor is filled with catalyst A (honeycomb effective volume 3.73 ml), the pressure of the inlet gas to the catalyst layer is 275 ° C. at normal pressure, and the steam / dimethyl ether ratio (S / D) The activity of the catalyst was evaluated with 5/1, GHSV 3320h- 1 . The gas after the reaction was analyzed by gas chromatography. Table 1 shows hydrogen, carbon monoxide (CO), methane, residual DME, residual methanol concentration, and DME reaction rate. The catalyst layer temperature is a temperature of 2 mm from the upper part of the honeycomb.
[0027]
Example 4
Example 3 was the same as Example 3 except that catalyst B was used instead of catalyst A.
[0028]
Comparative Example 4
Example 3 was the same as Example 3 except that Catalyst C was used instead of Catalyst A.
[0029]
Comparative Example 5
Example 3 was the same as Example 3 except that Catalyst D was used instead of Catalyst A.
[0030]
Comparative Example 6
Example 3 was the same as Example 3 except that Catalyst E was used instead of Catalyst A.
[0031]
Example 5
The reaction tube of the fixed bed flow reactor is filled with catalyst A (honeycomb effective volume 3.73 ml), the normal gas pressure at the inlet to the catalyst layer is 290 ° C., and the steam / dimethyl ether ratio (S / D) 5/1, GHSV 3320h −1 , air was introduced at an air / dimethyl ether ratio (A / D) of 2.53 to 3.15, total GHSV 5070 to 5400 h −1 , and the activity of the catalyst in the self-heating supply type reaction was evaluated. did. The gas after the reaction was analyzed by gas chromatography. Table 2 shows hydrogen, carbon monoxide (CO), methane, residual DME, residual methanol concentration, and DME reaction rate. The catalyst layer temperature is a temperature of 2 mm from the upper part of the honeycomb.
[0033]
Example 6
Example 5 was the same as Example 5 except that catalyst B was used instead of catalyst A.
[0034]
Comparative Example 7
Example 5 was the same as Example 5 except that Catalyst C was used instead of Catalyst A.
[0035]
Comparative Example 8
Example 5 was the same as Example 5 except that catalyst D was used instead of catalyst A.
[0036]
Comparative Example 9
Example 5 was the same as Example 5 except that Catalyst E was used instead of Catalyst A.
[0037]
【The invention's effect】
As is clear from the above examples, the catalyst according to the present invention performs a reforming reaction containing hydrogen as a main component by reacting dimethyl ether with water vapor, or performs a self-heating supply reaction in which air is introduced. In this case, a gas mixture can be obtained that maintains a high hydrogen concentration and contains very little by-products such as carbon monoxide, methane, or residual methanol. That is, if this dimethyl ether reforming catalyst is used, a gas mixture having a high hydrogen concentration can be easily produced with a small apparatus.
Claims (8)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001354731A JP4168230B2 (en) | 2001-11-20 | 2001-11-20 | Dimethyl ether reforming catalyst and method for producing hydrogen-containing gas using the catalyst |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001354731A JP4168230B2 (en) | 2001-11-20 | 2001-11-20 | Dimethyl ether reforming catalyst and method for producing hydrogen-containing gas using the catalyst |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2003154268A JP2003154268A (en) | 2003-05-27 |
| JP4168230B2 true JP4168230B2 (en) | 2008-10-22 |
Family
ID=19166538
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2001354731A Expired - Fee Related JP4168230B2 (en) | 2001-11-20 | 2001-11-20 | Dimethyl ether reforming catalyst and method for producing hydrogen-containing gas using the catalyst |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4168230B2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007091513A (en) * | 2005-09-28 | 2007-04-12 | Toshiba Corp | Hydrogen generator and fuel cell system |
| CN111359644B (en) * | 2020-03-18 | 2022-10-28 | 中国科学院广州能源研究所 | Non-noble metal-based molybdenum carbide catalyst for dimethyl ether steam reforming hydrogen production and preparation method and application thereof |
| CN113042039A (en) * | 2021-03-24 | 2021-06-29 | 中国科学院生态环境研究中心 | Palladium-based catalyst, and preparation method and application thereof |
-
2001
- 2001-11-20 JP JP2001354731A patent/JP4168230B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JP2003154268A (en) | 2003-05-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6051163A (en) | Catalyst for steam-reforming methanol | |
| JP3226558B2 (en) | Catalyst for high temperature steam reforming of hydrocarbons | |
| JP2000176287A (en) | Catalyst for methanol synthesis and synthetic method of methanol | |
| JP4724973B2 (en) | Dimethyl ether reforming catalyst and method for producing hydrogen-containing gas using the catalyst | |
| WO2003086627A1 (en) | Modification catalyst composition | |
| JP2003320254A (en) | Catalyst for water gas shift reaction and steam reforming reaction of methanol | |
| EP1312412B1 (en) | Process for producing hydrogen-containing gas | |
| JP3328845B2 (en) | Hydrogen production method and catalyst used for it | |
| JP4168230B2 (en) | Dimethyl ether reforming catalyst and method for producing hydrogen-containing gas using the catalyst | |
| EP1298089B1 (en) | Method for obtaining hydrogen by partial methanol oxidation | |
| JP2005066516A (en) | Catalyst for reforming dimethyl ether and synthesizing method therefor | |
| JP4525909B2 (en) | Water gas shift reaction catalyst, method for producing the same, and method for producing water gas | |
| JP4202087B2 (en) | Dimethyl ether reforming catalyst and method for producing hydrogen-containing gas using the catalyst | |
| JP3837520B2 (en) | Catalyst for CO shift reaction | |
| US5622790A (en) | Fuel cell and catalyst for use therein | |
| JPS59189937A (en) | Preparation of steam reforming catalyst of methanol | |
| JP3226556B2 (en) | Catalyst for steam reforming of hydrocarbons | |
| JP4350835B2 (en) | On-vehicle reforming method and apparatus for dimethyl ether | |
| JP2007516825A (en) | Reforming catalyst | |
| JP2001276620A (en) | Catalyst for reforming hydrocarbon | |
| JP2001185190A (en) | Producing method of hydrogen for fuel cell | |
| JP2004121924A (en) | Catalyst for steam-reforming dimethyl ether and method of producing hydrogen-containing gas by using the catalyst | |
| JP2005095738A (en) | Catalyst for steam reforming of dimethyl ether having solid acid-containing coating layer | |
| JPS6246482B2 (en) | ||
| JP2002059005A (en) | Methanol modifying catalyst, method for manufacturing the same and methanol modifying method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20041115 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20071001 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20071010 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20071207 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20080709 |
|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20080722 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110815 Year of fee payment: 3 |
|
| R151 | Written notification of patent or utility model registration |
Ref document number: 4168230 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R151 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110815 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110815 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120815 Year of fee payment: 4 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130815 Year of fee payment: 5 |
|
| LAPS | Cancellation because of no payment of annual fees |