WO2007104403A1 - Catalyst and process for the decomposition of nitrous oxide as well as process and device in nitric acid preparation - Google Patents
Catalyst and process for the decomposition of nitrous oxide as well as process and device in nitric acid preparation Download PDFInfo
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- WO2007104403A1 WO2007104403A1 PCT/EP2007/001381 EP2007001381W WO2007104403A1 WO 2007104403 A1 WO2007104403 A1 WO 2007104403A1 EP 2007001381 W EP2007001381 W EP 2007001381W WO 2007104403 A1 WO2007104403 A1 WO 2007104403A1
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- WIPO (PCT)
- Prior art keywords
- perovskite
- catalyst
- type compound
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- combinations
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- 238000000354 decomposition reaction Methods 0.000 title claims abstract description 49
- GQPLMRYTRLFLPF-UHFFFAOYSA-N Nitrous Oxide Chemical group [O-][N+]#N GQPLMRYTRLFLPF-UHFFFAOYSA-N 0.000 title claims description 173
- 239000001272 nitrous oxide Substances 0.000 title claims description 86
- 239000003054 catalyst Substances 0.000 title claims description 73
- 238000000034 method Methods 0.000 title claims description 43
- 230000008569 process Effects 0.000 title claims description 39
- 238000002360 preparation method Methods 0.000 title claims description 28
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 title claims description 25
- 229910017604 nitric acid Inorganic materials 0.000 title claims description 24
- 150000001875 compounds Chemical class 0.000 claims abstract description 87
- 229910052742 iron Inorganic materials 0.000 claims abstract description 17
- 229910052748 manganese Inorganic materials 0.000 claims abstract description 17
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 16
- 229910052746 lanthanum Inorganic materials 0.000 claims abstract description 15
- 229910052802 copper Inorganic materials 0.000 claims abstract description 14
- 229910052779 Neodymium Inorganic materials 0.000 claims abstract description 12
- 229910052684 Cerium Inorganic materials 0.000 claims abstract description 11
- 229910052777 Praseodymium Inorganic materials 0.000 claims abstract description 11
- 229910052772 Samarium Inorganic materials 0.000 claims abstract description 11
- 239000007789 gas Substances 0.000 claims description 44
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 40
- 230000003647 oxidation Effects 0.000 claims description 22
- 238000007254 oxidation reaction Methods 0.000 claims description 22
- 229910021529 ammonia Inorganic materials 0.000 claims description 20
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 14
- 229910052760 oxygen Inorganic materials 0.000 claims description 14
- 239000001301 oxygen Substances 0.000 claims description 14
- 239000012876 carrier material Substances 0.000 claims description 12
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 35
- 239000000203 mixture Substances 0.000 description 18
- 229910001868 water Inorganic materials 0.000 description 17
- 239000010970 precious metal Substances 0.000 description 15
- 230000000694 effects Effects 0.000 description 14
- PNEYBMLMFCGWSK-UHFFFAOYSA-N Alumina Chemical compound [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 13
- 229910052878 cordierite Inorganic materials 0.000 description 13
- 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 13
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 12
- 239000000969 carrier Substances 0.000 description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 11
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 10
- 230000015572 biosynthetic process Effects 0.000 description 9
- 230000003197 catalytic effect Effects 0.000 description 9
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 9
- 239000011248 coating agent Substances 0.000 description 9
- 238000000576 coating method Methods 0.000 description 9
- 239000000463 material Substances 0.000 description 8
- JCXJVPUVTGWSNB-UHFFFAOYSA-N nitrogen dioxide Inorganic materials O=[N]=O JCXJVPUVTGWSNB-UHFFFAOYSA-N 0.000 description 8
- 239000000243 solution Substances 0.000 description 8
- MGWGWNFMUOTEHG-UHFFFAOYSA-N 4-(3,5-dimethylphenyl)-1,3-thiazol-2-amine Chemical compound CC1=CC(C)=CC(C=2N=C(N)SC=2)=C1 MGWGWNFMUOTEHG-UHFFFAOYSA-N 0.000 description 7
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 7
- 229910002804 graphite Inorganic materials 0.000 description 7
- 239000010439 graphite Substances 0.000 description 7
- 150000002602 lanthanoids Chemical class 0.000 description 7
- 239000002243 precursor Substances 0.000 description 7
- 229910002089 NOx Inorganic materials 0.000 description 6
- 238000013459 approach Methods 0.000 description 6
- 229910052747 lanthanoid Inorganic materials 0.000 description 6
- 230000009467 reduction Effects 0.000 description 6
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 5
- 239000006185 dispersion Substances 0.000 description 5
- 239000008187 granular material Substances 0.000 description 5
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 5
- 229910052751 metal Inorganic materials 0.000 description 5
- 239000002245 particle Substances 0.000 description 5
- 238000000746 purification Methods 0.000 description 5
- 238000012360 testing method Methods 0.000 description 5
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 4
- 238000010521 absorption reaction Methods 0.000 description 4
- 230000004913 activation Effects 0.000 description 4
- 238000001354 calcination Methods 0.000 description 4
- 238000003421 catalytic decomposition reaction Methods 0.000 description 4
- 150000001768 cations Chemical class 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 4
- 229910052804 chromium Inorganic materials 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- 238000002156 mixing Methods 0.000 description 4
- 150000002823 nitrates Chemical class 0.000 description 4
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 4
- 238000011084 recovery Methods 0.000 description 4
- 238000005496 tempering Methods 0.000 description 4
- 229910052723 transition metal Inorganic materials 0.000 description 4
- 150000003624 transition metals Chemical class 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Natural products OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 3
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 3
- 239000005864 Sulphur Substances 0.000 description 3
- 230000032683 aging Effects 0.000 description 3
- 229910002092 carbon dioxide Inorganic materials 0.000 description 3
- 230000010354 integration Effects 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 3
- 229910052761 rare earth metal Inorganic materials 0.000 description 3
- 150000002910 rare earth metals Chemical class 0.000 description 3
- 230000002829 reductive effect Effects 0.000 description 3
- 229920006395 saturated elastomer Polymers 0.000 description 3
- 239000000377 silicon dioxide Substances 0.000 description 3
- 229910052712 strontium Inorganic materials 0.000 description 3
- 229910000314 transition metal oxide Inorganic materials 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 229910002321 LaFeO3 Inorganic materials 0.000 description 2
- 229910002651 NO3 Inorganic materials 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 239000002585 base Substances 0.000 description 2
- 229910052792 caesium Inorganic materials 0.000 description 2
- 229910052791 calcium Inorganic materials 0.000 description 2
- 239000001569 carbon dioxide Substances 0.000 description 2
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 2
- 238000006555 catalytic reaction Methods 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 229910052681 coesite Inorganic materials 0.000 description 2
- 238000011109 contamination Methods 0.000 description 2
- 229910052906 cristobalite Inorganic materials 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 230000007547 defect Effects 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
- KZHJGOXRZJKJNY-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Si]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O KZHJGOXRZJKJNY-UHFFFAOYSA-N 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 239000005350 fused silica glass Substances 0.000 description 2
- 239000001307 helium Substances 0.000 description 2
- 229910052734 helium Inorganic materials 0.000 description 2
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 2
- 230000005764 inhibitory process Effects 0.000 description 2
- 229910052749 magnesium Inorganic materials 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 229910052863 mullite Inorganic materials 0.000 description 2
- RVTZCBVAJQQJTK-UHFFFAOYSA-N oxygen(2-);zirconium(4+) Chemical compound [O-2].[O-2].[Zr+4] RVTZCBVAJQQJTK-UHFFFAOYSA-N 0.000 description 2
- 229910052697 platinum Inorganic materials 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 229910052700 potassium Inorganic materials 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 230000035939 shock Effects 0.000 description 2
- 229910052566 spinel group Inorganic materials 0.000 description 2
- 229910052682 stishovite Inorganic materials 0.000 description 2
- 239000005437 stratosphere Substances 0.000 description 2
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 2
- 229910052905 tridymite Inorganic materials 0.000 description 2
- 229910052720 vanadium Inorganic materials 0.000 description 2
- 229910001928 zirconium oxide Inorganic materials 0.000 description 2
- 229910016516 CuFe2O4 Inorganic materials 0.000 description 1
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical group CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 1
- 229910016152 MxMn Inorganic materials 0.000 description 1
- 229910003264 NiFe2O4 Inorganic materials 0.000 description 1
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 1
- 229910002637 Pr6O11 Inorganic materials 0.000 description 1
- 229910001260 Pt alloy Inorganic materials 0.000 description 1
- 229910000629 Rh alloy Inorganic materials 0.000 description 1
- 229910021536 Zeolite Inorganic materials 0.000 description 1
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 description 1
- NHWNVPNZGGXQQV-UHFFFAOYSA-J [Si+4].[O-]N=O.[O-]N=O.[O-]N=O.[O-]N=O Chemical compound [Si+4].[O-]N=O.[O-]N=O.[O-]N=O.[O-]N=O NHWNVPNZGGXQQV-UHFFFAOYSA-J 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 229910052768 actinide Inorganic materials 0.000 description 1
- 150000001255 actinides Chemical class 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 229910000323 aluminium silicate Inorganic materials 0.000 description 1
- VXAUWWUXCIMFIM-UHFFFAOYSA-M aluminum;oxygen(2-);hydroxide Chemical compound [OH-].[O-2].[Al+3] VXAUWWUXCIMFIM-UHFFFAOYSA-M 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 150000001450 anions Chemical class 0.000 description 1
- 229910052788 barium Inorganic materials 0.000 description 1
- JRPBQTZRNDNNOP-UHFFFAOYSA-N barium titanate Chemical compound [Ba+2].[Ba+2].[O-][Ti]([O-])([O-])[O-] JRPBQTZRNDNNOP-UHFFFAOYSA-N 0.000 description 1
- 229910002113 barium titanate Inorganic materials 0.000 description 1
- 229910052790 beryllium Inorganic materials 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 238000009529 body temperature measurement Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- CETPSERCERDGAM-UHFFFAOYSA-N ceric oxide Chemical compound O=[Ce]=O CETPSERCERDGAM-UHFFFAOYSA-N 0.000 description 1
- 229910000420 cerium oxide Inorganic materials 0.000 description 1
- 229910000422 cerium(IV) oxide Inorganic materials 0.000 description 1
- 239000003610 charcoal Substances 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000000975 co-precipitation Methods 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 229910000428 cobalt oxide Inorganic materials 0.000 description 1
- UBEWDCMIDFGDOO-UHFFFAOYSA-N cobalt(II,III) oxide Inorganic materials [O-2].[O-2].[O-2].[O-2].[Co+2].[Co+3].[Co+3] UBEWDCMIDFGDOO-UHFFFAOYSA-N 0.000 description 1
- IVMYJDGYRUAWML-UHFFFAOYSA-N cobalt(ii) oxide Chemical compound [Co]=O IVMYJDGYRUAWML-UHFFFAOYSA-N 0.000 description 1
- DXKGMXNZSJMWAF-UHFFFAOYSA-N copper;oxido(oxo)iron Chemical compound [Cu+2].[O-][Fe]=O.[O-][Fe]=O DXKGMXNZSJMWAF-UHFFFAOYSA-N 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000003795 desorption Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- KMHJKRGRIJONSV-UHFFFAOYSA-N dioxygen(.1+) Chemical compound [O+]=O KMHJKRGRIJONSV-UHFFFAOYSA-N 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000003337 fertilizer Substances 0.000 description 1
- 239000005431 greenhouse gas Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 238000005470 impregnation Methods 0.000 description 1
- 238000010348 incorporation Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N iron oxide Inorganic materials [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 1
- FZLIPJUXYLNCLC-UHFFFAOYSA-N lanthanum atom Chemical compound [La] FZLIPJUXYLNCLC-UHFFFAOYSA-N 0.000 description 1
- MRELNEQAGSRDBK-UHFFFAOYSA-N lanthanum oxide Inorganic materials [O-2].[O-2].[O-2].[La+3].[La+3] MRELNEQAGSRDBK-UHFFFAOYSA-N 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 1
- 229910052753 mercury Inorganic materials 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- VCRYGHPVKURQMM-UHFFFAOYSA-N methane;platinum Chemical compound C.[Pt] VCRYGHPVKURQMM-UHFFFAOYSA-N 0.000 description 1
- 229920000609 methyl cellulose Polymers 0.000 description 1
- 239000001923 methylcellulose Substances 0.000 description 1
- 235000010981 methylcellulose Nutrition 0.000 description 1
- PLDDOISOJJCEMH-UHFFFAOYSA-N neodymium oxide Inorganic materials [O-2].[O-2].[O-2].[Nd+3].[Nd+3] PLDDOISOJJCEMH-UHFFFAOYSA-N 0.000 description 1
- NQNBVCBUOCNRFZ-UHFFFAOYSA-N nickel ferrite Chemical compound [Ni]=O.O=[Fe]O[Fe]=O NQNBVCBUOCNRFZ-UHFFFAOYSA-N 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 235000006408 oxalic acid Nutrition 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- BMMGVYCKOGBVEV-UHFFFAOYSA-N oxo(oxoceriooxy)cerium Chemical compound [Ce]=O.O=[Ce]=O BMMGVYCKOGBVEV-UHFFFAOYSA-N 0.000 description 1
- KTUFCUMIWABKDW-UHFFFAOYSA-N oxo(oxolanthaniooxy)lanthanum Chemical compound O=[La]O[La]=O KTUFCUMIWABKDW-UHFFFAOYSA-N 0.000 description 1
- WHOPEPSOPUIRQQ-UHFFFAOYSA-N oxoaluminum Chemical compound O1[Al]O[Al]1 WHOPEPSOPUIRQQ-UHFFFAOYSA-N 0.000 description 1
- 229910052763 palladium Inorganic materials 0.000 description 1
- KDLHZDBZIXYQEI-UHFFFAOYSA-N palladium Substances [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 1
- 150000002940 palladium Chemical class 0.000 description 1
- 239000011049 pearl Substances 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 239000012495 reaction gas Substances 0.000 description 1
- 238000000518 rheometry Methods 0.000 description 1
- 229910052701 rubidium Inorganic materials 0.000 description 1
- FKTOIHSPIPYAPE-UHFFFAOYSA-N samarium(III) oxide Inorganic materials [O-2].[O-2].[O-2].[Sm+3].[Sm+3] FKTOIHSPIPYAPE-UHFFFAOYSA-N 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 1
- 229910010271 silicon carbide Inorganic materials 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 229910052596 spinel Inorganic materials 0.000 description 1
- 239000011029 spinel Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 239000000454 talc Substances 0.000 description 1
- 229910052623 talc Inorganic materials 0.000 description 1
- ZCUFMDLYAMJYST-UHFFFAOYSA-N thorium dioxide Chemical compound O=[Th]=O ZCUFMDLYAMJYST-UHFFFAOYSA-N 0.000 description 1
- 239000010936 titanium Substances 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 239000004408 titanium dioxide Substances 0.000 description 1
- 231100000167 toxic agent Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 238000010792 warming Methods 0.000 description 1
- 229910052727 yttrium Inorganic materials 0.000 description 1
- 239000010457 zeolite Substances 0.000 description 1
- 229910052726 zirconium Inorganic materials 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/002—Mixed oxides other than spinels, e.g. perovskite
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
- B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
- B01J23/83—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with rare earths or actinides
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
- B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
- B01J23/84—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
- B01J23/889—Manganese, technetium or rhenium
- B01J23/8892—Manganese
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/50—Catalysts, in general, characterised by their form or physical properties characterised by their shape or configuration
- B01J35/56—Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional monoliths
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/02—Impregnation, coating or precipitation
- B01J37/0215—Coating
- B01J37/0219—Coating the coating containing organic compounds
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B21/00—Nitrogen; Compounds thereof
- C01B21/20—Nitrogen oxides; Oxyacids of nitrogen; Salts thereof
- C01B21/24—Nitric oxide (NO)
- C01B21/26—Preparation by catalytic or non-catalytic oxidation of ammonia
- C01B21/265—Preparation by catalytic or non-catalytic oxidation of ammonia characterised by the catalyst
-
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Definitions
- a specific Perovskite-type compound represented by the general formula (1) is described.
- the invention relates to a catalyst containing a Perovskite-type compound. Furthermore a process for decomposing nitrous oxide (N 2 O), a device for preparation of nitric acid as well as a process for preparation of nitric acid is disclosed.
- the invention also relates to the use of the Perovskite-type compound for decomposition of N 2 O.
- Nitrous oxide is a climate relevant trace gas which, along with carbon dioxide and methane, contributes directly to man made and enhanced greenhouse effect. Not until in the stratosphere N 2 O is basically decomposed by photochemical processes wherein N 2 O has a 310 fold higher resistance compared to carbon dioxide and a correspondingly higher contribution to global warming of the atmosphere. Due to the formation of nitric oxide (NO) in the stratosphere N 2 O additionally significantly takes part in the depletion of the ozone layer.
- NO nitric oxide
- Nitric acid industry is one of the major industrial sources contributing to the direct entry of N 2 O into the atmosphere.
- Ostwald process ammonia is catalytically oxidized with atmospheric oxygen on multi layer stacked precious metal catalyst meshes based on platinum alloys wherein NO is formed as primary product.
- NO is oxidized with atmospheric oxygen to form nitrogen dioxide (NO 2 ). This is absorbed in water at elevated pressure yielding mainly nitric acid of 50 - 68 %.
- N 2 O is formed additionally to NO as an undesired secondary product. Unlike other nitrogen oxides formed N 2 O is not absorbed in water in the following absorption process. Without further downstream steps for removal of N 2 O it will enter the atmosphere, according to an analysis of the EFMA (European Fertilizer Manufactures Association) of 1995, with a exhaust gas concentration of 300 to 3500ppm, corresponding to a dimension of 1.2 to 13.8 kg per ton of product (HNO 3 ).
- EFMA European Fertilizer Manufactures Association
- the exhaust gas is heated to temperatures of 250 to 500 °C for heat recovery to gain energy via the exhaust gas expander.
- the relaxed exhaust gas is delivered to the atmosphere at a temperature of more than 100 0 C. Processes of N 2 O decomposition in the exhaust gas differ in their set up before or behind the expander and thus in the working temperature for the used decomposition catalyst.
- precious metal-free catalysts for ammonia oxidation can for example be found in US-A-4,812,300 and US-B-6,489,264.
- A is an alkali, alkaline earth, rare earth, lanthanide or actinide metal.
- B is an element or a combination of elements selected of the group consisting of IB, IVB, VB, VIB, VHB or Vm of the periodic table of elements. Preferably used are La, Sr and mixtures thereof for A; Cr, Mn, Co, Ni, Cu and mixtures thereof for B.
- This catalyst is to allow for a selective oxidation of ammonia to form NO with a minimum of N 2 O formation depending on temperature.
- a catalyst represented by the general formula (A x B y ⁇ 3Z ) k (Me m O n ) f for the oxidation of ammonia is described.
- k and f refer to % by weight with a ratio of k to f of 0.01 to 1.
- A is Ca, Sr, Ba, Mg, Be, La or a mixture thereof and B is Mn, Fe, Ni, Co, Cr, Cu, V or a mixture thereof, x is 0 to 2, z is 1 to 2 and z is 0.8 to 1.7.
- Me m O n is a specific metal oxide.
- a pure catalytic decomposition of N 2 O has been known for catalysts, such as silicon dioxide, titanium dioxide, aluminium dioxide, thorium dioxide, platinum foil and charcoal.
- catalysts such as silicon dioxide, titanium dioxide, aluminium dioxide, thorium dioxide, platinum foil and charcoal.
- Examples for catalysts that are supposed to be suitable for the decomposition of N 2 O and which are applied directly downstream to the precious metal catalyst for ammonia oxidation, are found in DE-A- 198 41 740, US-A-2004/0179986, US-A-2005/0202966, US-B-6,723,295 and WO 2004/052512.
- a catalyst for the decomposition of N 2 O into N 2 and O 2 is described, containing a lanthanum-containing Perovskite.
- US-A-5,562,888 relates to a process for catalytic decomposition of N 2 O in the presence of oxygen by using a solid oxide solution of the formula La O sSr 02 MO 3 ⁇ .
- M is a transition metal, preferably Cr, Mn, Fe, Co or Y and ⁇ is the deviation from the balanced stoichiometry.
- US-A-3, 884,837 discloses a catalyst represented by the general formula RE 1-x M x M n ⁇ 3 wherein RE is one or more of the elements La, Pr and Nd, M is a monovalent ion, e.g. Na, K or Rb, and x ranges from 0.05 to 0.5.
- This compound is to catalyse decomposition of NO x toxics into non harmful products.
- N 2 O and nitrogen are listed as non harmful products.
- a decomposition of N 2 O is, however, not described in the US-A-3,884,837.
- US-B-6,569,803 relates to a catalyst for the purification of exhaust gases, where at least one specific precious metal catalyst component is supported on a complex oxide of the Perovskite type comprising at least two different metal elements.
- the complex oxide has the formula La 1-x K x B ⁇ 3 In one preferred embodiment wherein B is at least one of the elements Mn, Co, Fe and Ni and wherein 0 ⁇ x ⁇ 1.
- This catalyst is to allow for a high NO x purification performance at high temperatures.
- EP-A-O 089 199 relates to a catalyst consisting basically of a Perovskite represented by the general formula La d . x /2Sr (1+X) /2Co 1-x Me x O 3 .
- Me is an element selected of the group consisting of Fe, Mn, Cr, V and Ti, and x is a number from 0.15 to 0.90.
- the catalyst is said to be suitable for the simultaneous treatment of oxidative and reductive gases.
- the catalytic oxidation of NO from car exhaust gases to form NO 2 and/or NO 3 has also been described in the state of the art.
- US-A-5,990,038 relates to a specific catalyst for the purification of exhaust gases.
- the catalytic layer of the catalyst comprises two types of granule. One including a double oxide represented by the formula (Lai -x A x )i. ⁇ BO ⁇ supporting a precious metal selected of the group consisting of Pt and Pd.
- A is at least one element selected of the group consisting of Ba, K and Cs.
- B is at least one transition metal selected of the group consisting of Fe, Co, Ni and Mn.
- This catalyst is to allow for a smooth oxidation from NO to form NO 2 and/or NO 3 due to the interaction between the double oxide and the precious metal.
- US-B-6,395,675 discloses a device for purification of exhaust gases comprising a catalyst for purification of exhaust gas.
- the catalyst comprises, amongst others, a powder of a double oxide represented by the general formula (Lni - ⁇ A ⁇ )i- ⁇ BO ⁇ .
- a and ⁇ are numbers between 0 and 1, ⁇ is a number larger than 0.
- Ln is at least one first element selected of the group consisting of La, Ce, Nd and Sm.
- A is at least one second element selected of the group consisting of Mg, Ca, Sr, Ba, Na, K and Cs.
- B is at least one third element selected of the group consisting of Fe, Co, Ni and Mn. Wherein the third element is to oxidize NO x to form NO 2 .
- Perovskites are also applied in other technical fields.
- US-A-5,447,705 describes the use of specific catalysts of the composition Ln x A t . y B y O 3 in the preparation of synthesis gas.
- x is between 0 and 10 and y is between 0 and 1.
- Ln is at least one element selected from the rare earths with the atomic numbers 57 through 71.
- a and B are metals that differ from each other selected of the groups IVb, Vb, VIb, VIIb and VHI.
- Another problem observed in association with a variety of catalysts so far proposed for the decomposition of N 2 O is the inhibition by the oxygen present in the product gas and exhaust gas respectively. Operating performance of these catalysts is only guaranteed when a reducing agent is present in the gas stream for the removal of the physically or chemically adsorbed oxides. It was an object of the present invention to provide a catalyst for the decomposition of N 2 O.
- the catalyst was supposed to be particularly suitable for the use in the decomposition of N 2 O in the product gas of ammonia oxidation in nitric acid preparation.
- the invention relates to a catalyst comprising a carrier in form of honeycomb and a Perovskite- type compound represented by the general formula (1)
- M 1 is selected of the group consisting of La, Ce, Nd, Pr, Sm and combinations thereof
- M 2 is selected of the group consisting of Fe, Ni and combinations thereof
- M 3 is selected of the group consisting of Cu, Co, Mn and combinations thereof.
- the present invention also relates to a process for decomposing N 2 O wherein N 2 O is brought into contact with a Perovskite-type compound represented by the general formula (1)
- M 1 is selected of the group consisting of La, Ce, Nd, Pr, Sm and combinations thereof
- M 2 is selected of the group consisting of Fe, Ni and combinations thereof
- M 3 is selected of the group consisting of Cu, Co, Mn and combinations thereof.
- the invention relates to a device for preparation of nitric acid comprising a Perovskite-type compound represented by the general formula (1)
- M 1 is selected of the group consisting of La, Ce, Nd, Pr, Sm and combinations thereof
- M 2 is selected of the group consisting of Fe, Ni and combinations thereof
- M 3 is selected of the group consisting of Cu, Co, Mn and combinations thereof, and a catalyst for ammonia oxidation.
- M 1 is selected of the group consisting of La, Ce, Nd, Pr, Sm and combinations thereof
- M 2 is selected of the group consisting of Fe, Ni and combinations thereof
- M 3 is selected of the group consisting of Cu, Co, Mn and combinations thereof, for the decomposition of N 2 O is also described.
- Figure 1 shows the N 2 O decomposition rate and the activation energy of the process for LaMO 3 - Perovskites.
- the Perovskite-type compound has the following general formula (1)
- x is at least 0.0, preferably at least 0.05, more preferably at least 0.1, even more preferably at least 0.15. x is at most 0.9, preferably at most 0.6, more preferably at most 0.4, even more preferably at most 0.25.
- M 1 is selected of the group consisting of La, Ce, Nd, Pr, Sm and combinations thereof.
- M 1 is preferably La.
- M 1 is preferably a combination of the indicated lanthanides, for example a combination of 50 to 55 % by weight Ce, 25 to 30 % by weight La, 10 to 15 % by weight Nd, 5 to 10 % by weight Pr as well as 0 to 1 % by weight Sm, calculated as oxide respectively.
- a combination of lanthanides is abbreviated as Ln.
- M 2 is selected of the group consisting of Fe, Ni and combinations thereof.
- M 3 is selected of the group consisting of Cu, Co, Mn and combinations thereof. Preferred are Cu and Co, more preferred is Co.
- Preferred compounds are:
- M 1 Fe C4 - O sNi 06 - O aO 3 preferably M 1 Fe 04 Ni 0 OO 3 and M l Feo. 8 Nio .2 O 3
- M 1 is preferably La or Ln.
- the Perovskite-type compound can be used in different forms as a catalyst.
- the Perovskite-type compound can, for example, be used as such in form of regularly or irregularly shaped particles (powder, granulate, granules).
- the Perovskite-type compound is used in combination with a carrier.
- the carrier can have any known form. Thus, amongst others, granules, pearls or honeycomb carriers are possible.
- carriers in the shape of honeycomb are used. These offer a mostly approximately cylindrical outer shape, pervaded by a variety of parallel channels. Such carriers of the honeycomb type are known in the field of catalysis.
- the carrier itself consists mostly of oxidic material (e.g.
- the Perovskite-type compound can be incorporated in the material of the carrier, the carrier can be impregnated with the Perovskite-type compound or the carrier can have a surface coating ("washcoat"), containing the Perovskite-type compound.
- the carrier has a surface coating containing the Perovskite-type compound
- the Perovskite-type compound can be applied to a carrier material contained in the surface coating.
- carrier material Preferably high- surface materials are used as carrier material. In the scope of this invention, materials are referred to as high-surface, the specific BET-surface of which being larger than 5 m 2 /g.
- Suitable carrier materials are for example titanium oxide, aluminium oxide, silicon oxide, cerium oxide, zirconium oxide, zeolite and mixtures or mixed oxides thereof.
- the carrier material comprises aluminium oxide, as this can additionally slow down the aging of the catalyst.
- a carrier provided with a surface coating can be produced in different ways.
- the carrier can be provided and then a coating comprising carrier material and Perovskite-type compound can be applied.
- a coating comprising carrier material can be applied and then the Perovskite-type compound can be applied. Processes for performing these steps are known in the state of the art.
- a dispersion of the Perovskite-type compound and the other coating components, including carrier material or precursors thereof, can be prepared.
- the Perovskite-type compound can already be present on the carrier material or it can be present separately in the dispersion.
- the carrier can be immersed in said dispersion once or several times. Then, residual dispersion can, wherever necessary, be removed from the channels of the carrier and the catalyst can be completed, for example by drying and calcination.
- the Perovskite-type compound preferably has the formulas M 1 FeCS-I oCUo 2 -OoO 3 and M 1 FeO more preferably M 1 Fe O 4 NiO 6 Os); wherein M 1 is more preferably La.
- these compounds are characterized a by high resistance towards modifications with components of the carrier material, such as the formation of less active spinels.
- the activity, particularly of the Perovskite-type compound with the formula LaFeo.8-i.oCuo. 2 -o.o0 3 is hardly influenced by changes in the contents of oxygen and water in the gas stream. An influence on selectivity in the presence of NO/NO 2 in the gas stream is not detectable.
- the Perovskite-type compound is incorporated into the material of the carrier.
- the carrier preferably comprises the Perovskite-type compound in an amount of 50 to 90 % by weight, preferably of 55 % by weight to 70 % by weight, referring to the total weight of the carrier.
- the carrier can additionally contain common components. Among them are oxidic materials that are, for example, resistant up to a temperature of 1200 0 C. Examples of such compounds are cordierite, alumina, graphite, mullite, aluminium oxide, zirconium oxide, zirconium mullite, barium titanate, titanium oxide, silicon carbide and silicon nitrite.
- the carrier comprises cordierite besides the compounds of the Perovskite type, preferably in an amount of 0 % by weight to 50 % by weight, preferably of 0 % by weight to 15 % by weight, alumina in an amount of 0 % by weight to 50 % by weight, particularly preferred 0 % by weight to 30 % by weight, and Al 2 O 3 in an amount of 0 % by weight to 50 % by weight, particularly preferred 10 % by weight to 30 % by weight.
- extrudates contain 25 to 30 % by weight Al 2 O 3 , 8 to 10 % by weight cordierite and about 5 % by weight graphite.
- the carrier consists of the Perovskite-type compound.
- the Perovskite-type compound has the formula M 1 Ni O 9-07 Co O i -O 3 O 3 , preferably M 1 Ni 08 Co 02 O 3 wherein M 1 is preferably La.
- these compounds show a low activation energy of about 30 kcal/mol for the observed N 2 O decomposition, allowing a universal use in a wide temperature range. Particularly in the typical temperature range from 850 to 900 0 C for the decomposition of N 2 O in nitric acid preparation, a doubling of the N 2 O decomposition is found.
- the examinations show a linear relationship of the decomposition efficiency with the amount of catalyst used in said temperature range. An influence on selectivity in the presence of NO/NO 2 in the test gas is not detectable.
- N 2 O decomposition X Reaction rate W, N 2 O decomposition X and activation energy E A at the N 2 O decomposition for LaMC ⁇ catalysts (at 900 °C).
- the N 2 O decomposition X is defined as the quotient of reacted amount of N 2 O to supplied amount of N 2 O.
- preferred compounds of the Perovskite type are M 1 Fe O g- I oCUo 2 - O oO 3 and M 1 Fe 03 - O gN ⁇ -0 1 O 3 (preferably M 1 Fe 04 - O sNi O o-OaO 3 , more preferably M 1 FeO 8 Ni 02 O 3 ).
- M 1 is preferably Ln.
- Carriers comprising respective extrudates have a surprisingly high porosity. Furthermore, the formation of NiFe 2 O 4 or CuFe 2 O 4 spinels seems to significantly increase the catalytic activity with regard to the N 2 O decomposition in these compounds. Besides, a minor dependence of the N 2 O decomposition activity of varying contents of water, oxygen as well as the presence of N0/N0 2 in the reaction gas is observed.
- LaFeO 3 has also proven to be particularly effective.
- This Perovskite-type compound has a high activity in N 2 O decomposition.
- the present invention relates to a process for decomposing N 2 O wherein N 2 O is brought into contact with the Perovskite-type compound.
- N 2 O is brought into contact with the Perovskite-type compound.
- the decomposition basically N 2 and O 2 are formed.
- the conditions where the Perovskite-type compound is brought into contact with the N 2 O are not particularly limited.
- the reaction temperature can be 800 to 1200 0 C.
- the amount of Perov ski te- type compound used conforms to the application and can suitably be appreciated by one with ordinary skill in the art.
- the contact time between catalyst and N 2 O also depends on the application and is preferably more than 0.02 sec.
- the catalyst according to the invention can also be used when the N 2 O containing gas stream contains water, oxygen, NO or NO x , it can be used in a wide variety of applications wherein N 2 O is to be decomposed.
- the process according to the invention is particularly suitable for the decomposition of N 2 O in the product gas of the ammonia oxidation in nitric acid preparation.
- the present invention also relates to a device for preparation of nitric acid comprising a Perovskite-type compound and a catalyst for ammonia oxidation.
- Devices for the preparation of nitric acid are known in the art and are, for example, described in Kirk-Othmer, Encyclopedia of Chemical Technology, Vol. 17, 4 th edition (1996), pages 84 to 96.
- the device according to the invention differs from the previous devices in that additionally the Perovskite-type compound is used for the decomposition of N 2 O. Thereby emissions of harmful N 2 O can be reduced.
- the Perovskite-type compound is downstream in the direction of flow to the catalyst for the oxidation of ammonia.
- the absorption of nitrogen oxides in water take place in the device according to the invention.
- the Perovskite-type compound can be present in one of the above described catalyst forms. It is, however, preferably used in combination with a carrier in the shape of honeycomb.
- honeycomb carrier with the Perovskite-type compound represented by the general formula (1) is, for example, placed in the reactor for catalytic ammonia oxidation on a carrier in the form of a grid, lattice or in a basket. If honeycomb carriers are used, one carrier or several carriers can be used. In such a device, the honeycomb carrier can take over the carrier function for the imposed precious metal catalyst and the precious metal recovery system, possibly located directly downstream. In the device according to the invention precious metal catalyst and precious metal recovery system can be separated from the honeycomb carrier by one or more separator meshes, for example made of non-precious metal. Because of the device according to the invention, a uniform flow through the precious metal catalyst and the carrier in the shape of honeycomb is achieved.
- the device according to the invention is advantageous, because the honeycomb carrier allows for a uniform flow at minimal pressure loss.
- An adaptation to the specific operating conditions of a nitric acid reactor and the N 2 O contents in the process gas is readily possible by respective modifications of the channel openings, their number and wall thickness.
- the preparation of the compounds of the Perovskite type is not particularly limited and any process for the preparation of compounds of the Perovskite type known in the art can be used. Among these processes are coprecipitation, impregnation, sol-gel techniques and mechanical mixing of oxides or precursors of oxides, followed by calcination.
- Pechini process [M. P. Pechini, US-A- 3,330,697].
- citric acid and ethylene glycol are added to a solution of the accordingly proportioned nitrate salts saturated at room temperature.
- the solution is evaporated at 80 to 100 °C.
- After tempering at 200 to 250 °C an amorphous Perovskite precursor will be formed.
- the sample is calcined for 4 hours at 700 to 900 °C.
- transition metal oxides such as Ot-Fe 2 O 3 , CoO, CuO, MnO, NiO and the respective carbonates of the lanthanides are mixed.
- the mixed oxides of the rare earth and transition metals are obtained by mixing for example Ln 2 (CO 3 ) 3 / Fe 2 O 3 in a weight ratio of 4.5 : 1.0.
- Fe 2 O 3 can also be replaced by one or more further transition metal oxides.
- the mixture will then be fed to a disintegrator for several times. After tempering at 700 to 900 0 C over a period of 4 hours the resulting mixture is repeatedly triturated in the disintegrator.
- Citric acid and ethylene glycol are added to a solution of the accordingly proportioned nitrate salts, saturated at room temperature.
- a commercially available honeycomb carrier based on cordierite is immersed in the solution for 5 to 10 min, blown off with air and dried at air at room temperature. Calcination will then be conducted at temperatures between 700 and 900 °C over a period of 4 hours.
- a Perovskite-type compound is added to a cordierite or Al 2 O 3 paste for the preparation of a honeycomb carrier.
- a solution of accordingly proportioned nitrate salts of the Perovskite-type compound can be added to the paste.
- the paste can contain an aqueous solution of methyl cellulose.
- alumina, talc and 3d oxides can be added in the required ratios.
- the paste is mixed in a mixer for a period of 40 min.
- the resulting paste has a humidity of 20 to 30 %. It will then be extruded through a pressure template to form a mould.
- the resulting monoliths are hardened at room temperature and dried at 300 to 400 °C over a period of 4 hours. Afterwards calcination is conducted at a temperature of 1000 to 1250 0 C over a period of 4 to 5 hours.
- Citric acid and ethylene glycol are added to a solution of the accordingly proportioned nitrate salts, saturated at room temperature, and said solution is evaporated at 80 to 100 0 C.
- polymerized metal ether complexes form.
- the organic residue will be incinerated and an amorphous precursor of the Perovskite has formed.
- the amorphous precursor is tempered at 700 to 900 °C over a period of 4 hours.
- transition metal oxides Ot-Fe 2 O 3 , NiO and CuO as well as carbonates of mixed lanthanides (Ln) are used as starting material.
- the composition of these mixed lanthanides is 50 to 55 % by weight Ce, 25 to 30 % by weight La, 10 to 15 % by weight Nd, 5 to 10 % by weight Pr as well as 0 to 1 % by weight Sm, stated as their oxides CeO 2 , La 2 O 3 , Nd 2 O 3 , Pr 6 O 11 and Sm 2 O 3 .
- a mixture of the rare earth and transition metals is achieved by mixing 3.5 kg Ln 2 (CO 3 ) 3 with 1.3 kg Fe 2 O 3 and CuO or NiO respectively. After mixing the mixture will be tempered at 700 to 900 °C over a period of 4 hours to obtain the Perovskite-type compound.
- the Perovskite-type compound is plasticized with a binder based on Al 2 O 3 (Al 2 O 3 • n H 2 O) or alumina (Al 2 O 3 / 20 - 25 % by weight, SiO 2 / 55 - 60 % by weight, H 2 O / 10 - 15 % by weight, rest admixtures) (as well as a peptisizing agent, for example an aqueous solution of different acids, such as nitric, oxalic and acetic acid).
- ethylene glycol is added.
- cordierite particles (2 MgO • 2 Al 2 O 2 • 5 SiO 2 ) with a particle size of less than 0.5 mm and graphite can be added.
- Such components will increase the thermal shock stability and the porosity of the catalyst material respectively.
- the mixture is treated mechanically over a period of 10 min in a planetary ball mill and will then be extruded to form a honeycomb carrier. After drying at room temperature, the honeycomb carrier is calcined at 900 to 1150 0 C over a period of 4 hours.
- the described compounds of the Perovskite type represent a significant progress in N 2 O decomposition as they have a high thermal shock resistance. This is of particular importance for a use in the Ostwald process as excessive temperature differences occur especially during starting up and shutting down the reactor. Furthermore, the compounds of the Perovskite type have a high aging stability even at high temperatures, as they prevail, for example, in the product gas stream of nitric acid preparation. They can also be used in applications wherein the gas stream contains sulphur and sulphur containing compounds, oxygen, water, NO or NO x besides N 2 O.
- the catalytic decomposition of N 2 O is conducted in a U-shaped fused quartz flow reactor with an internal diameter of 11.4 mm at ambient pressure. For uniform tempering, the reactor is placed in an electrically heated sand bath.
- Measurement and regulation of the reactor temperature takes place on the external wall of the reactor. Additionally, the catalyst temperature is taken by a temperature measurement in one of the honeycomb channels. The flow rates of the gas mixtures are set in a range of 0.5 to 3.2 1/min by mass flow controllers. Steam is added by a saturator at given temperature. In order to exclude the formation of potential condensates all elements and sampling systems flown through by gas are heat insulated and heated.
- a bulk of inactive fused quartz granules (1 to 2 mm in diameter, total mass of 1 g) is filled into the test reactor.
- a catalyst bed of 5 to 20 mg of particles of the Perovskite-type compound with a particle size of 0.25 to 0.50 mm is placed.
- the BET-surface of the Perovskite-type compound varies from 1 to 10 m 2 /g.
- Each measurement is conducted at constant temperature in stationary state.
- comparable measurement without catalyst will be conducted.
- the results besides the absolute reaction of N 2 O, are applied to the reaction rate W in mole N 2 O / m 2 s.
- a cordierite carrier with a surface area of 35 m 2 /g and a pore volume of 0.4 cm 3 /g is selected.
- the carrier has a honeycomb structure with a hexagonal base area as well as isosceles, triangular channel openings having a side length of 2.5 mm and a wall thickness of 0.4 mm.
- such carriers with a diameter of 9 to 10 mm are used. The results are set forth in table 5 to 7.
- the weight ratio is related to the total weight of the honeycomb carrier.
- Carriers in the shape of honeycomb containing a Perovskite-comprising extrudate are examined. Two different geometries are used for the examination and testing.
- a first series comprises hexagonal prisms with a side length of 6.0 cm and a triangular channel geometry with a side length of 2.5 mm and a wall thickness of 0.4 mm.
- a second series comprises hexagonal prisms with a side length of 2.8 cm, with a triangular channel geometry with a side length of 1.6 mm and a wall thickness of 0.6 mm.
- the samples were cut out of the produced honeycomb carriers respectively. The form was chosen in such way that the samples fit into the test reactor.
- the activity of the catalyst is determined for a temperature range of 800 to 900 0 C.
- a standard gas composition consists of 0.15 % N 2 O, 3 % O 2 and 3 % H 2 O, balance helium.
- a gas composition of 0.13 % N 2 O, 7 % O 2 and 3 % H 2 O, balance helium is used.
- the portion of steam is increased to 10 to 12 %. All listed values are corrected for the value of the homogenous high temperature self- decomposition of N 2 O.
- the pore volume is measured with a high-pressure mercury porosimeter.
- the surface area is detected by the common BET procedure by using thermic Ar desorption.
- the H 2 O saturator is operated at different temperatures.
- an extruded honeycomb carrier with a Perovskite-type compound LaFeO 3 is set onto the grid of a basket.
- two base Megapyr separator meshes are used for spacing of the precious metal catalyst and the platinum recovery system.
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Abstract
A Perovskite-type compound represented by the general formula (1), is described wherein x ranges from 0.0 to 0.9, M1 is selected of the group consisting of La, Ce, Nd, Pr, Sm and combinations thereof, M2 is selected of the group consisting of Fe, Ni and combinations thereof, and M3 is selected of the group consisting of Cu, Co, Mn and combinations thereof. The compounds of the Perovskite type are used for the decomposition of N2O.
Description
Catalyst and process for the decomposition of nitrous oxide as well as process and device in nitric acid preparation
A specific Perovskite-type compound represented by the general formula (1) is described. The invention relates to a catalyst containing a Perovskite-type compound. Furthermore a process for decomposing nitrous oxide (N2O), a device for preparation of nitric acid as well as a process for preparation of nitric acid is disclosed. The invention also relates to the use of the Perovskite-type compound for decomposition of N2O.
Nitrous oxide is a climate relevant trace gas which, along with carbon dioxide and methane, contributes directly to man made and enhanced greenhouse effect. Not until in the stratosphere N2O is basically decomposed by photochemical processes wherein N2O has a 310 fold higher resistance compared to carbon dioxide and a correspondingly higher contribution to global warming of the atmosphere. Due to the formation of nitric oxide (NO) in the stratosphere N2O additionally significantly takes part in the depletion of the ozone layer.
Nitric acid industry is one of the major industrial sources contributing to the direct entry of N2O into the atmosphere. In the so called Ostwald process ammonia is catalytically oxidized with atmospheric oxygen on multi layer stacked precious metal catalyst meshes based on platinum alloys wherein NO is formed as primary product. NO is oxidized with atmospheric oxygen to form nitrogen dioxide (NO2). This is absorbed in water at elevated pressure yielding mainly nitric acid of 50 - 68 %.
In the catalytic process N2O is formed additionally to NO as an undesired secondary product. Unlike other nitrogen oxides formed N2O is not absorbed in water in the following absorption process. Without further downstream steps for removal of N2O it will enter the atmosphere, according to an analysis of the EFMA (European Fertilizer Manufactures Association) of 1995, with a exhaust gas concentration of 300 to 3500ppm, corresponding to a dimension of 1.2 to 13.8 kg per ton of product (HNO3).
Due to the resolutions of the Kyoto protocol assigning mandatorial reduction of the six greenhouse gases CO2, CH4, N2O, partially halogenated hydrofluorocarbons (HFCs), perfluorinated hydrocarbons (PFCs) and SF6 in total, the contracting states of the United Nations Framework Convention on Climate Change are obliged to take measures for the reduction of N2O emissions in nitric acid preparation.
This provision of the Kyoto protocol has initiated the examination and development of different techniques for N2O reduction in nitric acid preparation which mainly differ in their set up in the diverse process steps. Among them in particular measures of integration in the process of catalytic oxidation of ammonia, catalytic decomposition directly downstream to the precious metal catalyst for ammonia oxidation and the decomposition in the exhaust gas after the absorption step.
After the absorption step the exhaust gas is heated to temperatures of 250 to 500 °C for heat recovery to gain energy via the exhaust gas expander. The relaxed exhaust gas is delivered to the atmosphere at a temperature of more than 100 0C. Processes of N2O decomposition in the exhaust gas differ in their set up before or behind the expander and thus in the working temperature for the used decomposition catalyst.
Especially with respect to existing plants, such refitting with a decomposition unit in the exhaust gas is associated with considerable costs as only few of these plants achieve the necessary exhaust gas temperature so that by such exhaust gas preheating the operational costs would also significantly increase.
Low cost process approaches would reside in an alternative catalyst for ammonia oxidation, integration of a catalyst for selective N2O decomposition in the process of catalytic ammonia oxidation or selective decomposition of N2O in the product gas directly downstream to the precious metal catalyst.
Alternatively precious metal-free catalysts for ammonia oxidation can for example be found in US-A-4,812,300 and US-B-6,489,264.
In US-A-4,812,300 a catalyst represented by the general formula ABO3 with Perovskite structure is described. Wherein A is an alkali, alkaline earth, rare earth, lanthanide or actinide metal. B is
an element or a combination of elements selected of the group consisting of IB, IVB, VB, VIB, VHB or Vm of the periodic table of elements. Preferably used are La, Sr and mixtures thereof for A; Cr, Mn, Co, Ni, Cu and mixtures thereof for B. This catalyst is to allow for a selective oxidation of ammonia to form NO with a minimum of N2O formation depending on temperature.
In US-B-6,489,264 a catalyst represented by the general formula (AxByθ3Z)k(MemOn)f for the oxidation of ammonia is described. Wherein k and f refer to % by weight with a ratio of k to f of 0.01 to 1. A is Ca, Sr, Ba, Mg, Be, La or a mixture thereof and B is Mn, Fe, Ni, Co, Cr, Cu, V or a mixture thereof, x is 0 to 2, z is 1 to 2 and z is 0.8 to 1.7. MemOn is a specific metal oxide.
Disadvantageously is, besides the poor product selectivity, in particular the low amount of process heat generated which would necessitate a separate pre heating of the educt mixed gas with respective additional costs and which could not be realized in that way in the existing plants used for nitric acid preparation.
Examples for an integration approach are found in WO 99/64352 and WO 01/87771. The former relates to a partial substitution of the precious metal catalyst by a cobalt oxide-containing catalyst, the latter to a combination with a modified palladium/rhodium alloy. Both patent applications describe a reduction of N2O emissions. They have, however, the disadvantages of high sensitivity towards contaminations or rapid aging behaviour.
A pure catalytic decomposition of N2O has been known for catalysts, such as silicon dioxide, titanium dioxide, aluminium dioxide, thorium dioxide, platinum foil and charcoal. Examples for catalysts that are supposed to be suitable for the decomposition of N2O and which are applied directly downstream to the precious metal catalyst for ammonia oxidation, are found in DE-A- 198 41 740, US-A-2004/0179986, US-A-2005/0202966, US-B-6,723,295 and WO 2004/052512.
In DE 197 00 490 Al a catalyst for the decomposition of N2O into N2 and O2 is described, containing a lanthanum-containing Perovskite. The catalyst consists of a mixture of an anion defective Perovskite of the composition Lai-xCuχCoO3-δ' with x = 0 to 0.5 and a spinel of the composition Co3O4 in the mass ratio up to 1:1.
In one embodiment US-A-5,562,888 relates to a process for catalytic decomposition of N2O in the presence of oxygen by using a solid oxide solution of the formula LaOsSr02MO3^. M is a
transition metal, preferably Cr, Mn, Fe, Co or Y and δ is the deviation from the balanced stoichiometry.
Both types of catalysts described above fail, however, at high temperatures in the range of 800 to 1200 0C, as they prevail in particular for the reduction of the content of N2O in the process gases in nitric acid preparation.
A series of catalysts for the decomposition of NOx from car exhaust gases is known in the art.
US-A-3, 884,837 discloses a catalyst represented by the general formula RE1-xMxMnθ3 wherein RE is one or more of the elements La, Pr and Nd, M is a monovalent ion, e.g. Na, K or Rb, and x ranges from 0.05 to 0.5. This compound is to catalyse decomposition of NOx toxics into non harmful products. N2O and nitrogen are listed as non harmful products. A decomposition of N2O is, however, not described in the US-A-3,884,837.
In US-A-4, 126,580 a specific catalyst represented by the general formula ABO3 having Perovskite crystal structure is described which is said to be, among others, suitable for the reduction of nitrogen oxides to form compounds with a lower oxidation state.
US-B-6,569,803 relates to a catalyst for the purification of exhaust gases, where at least one specific precious metal catalyst component is supported on a complex oxide of the Perovskite type comprising at least two different metal elements. Wherein the complex oxide has the formula La1-xKxBθ3 In one preferred embodiment wherein B is at least one of the elements Mn, Co, Fe and Ni and wherein 0 < x < 1. This catalyst is to allow for a high NOx purification performance at high temperatures.
EP-A-O 089 199 relates to a catalyst consisting basically of a Perovskite represented by the general formula Lad.x/2Sr(1+X)/2Co1-xMexO3. Me is an element selected of the group consisting of Fe, Mn, Cr, V and Ti, and x is a number from 0.15 to 0.90. The catalyst is said to be suitable for the simultaneous treatment of oxidative and reductive gases.
The catalytic oxidation of NO from car exhaust gases to form NO2 and/or NO3 has also been described in the state of the art.
US-A-5,990,038 relates to a specific catalyst for the purification of exhaust gases. The catalytic layer of the catalyst comprises two types of granule. One including a double oxide represented by the formula (Lai-xAx)i.αBOδ supporting a precious metal selected of the group consisting of Pt and Pd. A is at least one element selected of the group consisting of Ba, K and Cs. B is at least one transition metal selected of the group consisting of Fe, Co, Ni and Mn. x is a number between 0 and 1, α is a number between 0 and 0.2, and δ is a number selected such that the total charge of the first double oxide is 0. This catalyst is to allow for a smooth oxidation from NO to form NO2 and/or NO3 due to the interaction between the double oxide and the precious metal.
US-B-6,395,675 discloses a device for purification of exhaust gases comprising a catalyst for purification of exhaust gas. The catalyst comprises, amongst others, a powder of a double oxide represented by the general formula (Lni-αAα)i-βBOδ. a and β are numbers between 0 and 1, δ is a number larger than 0. Ln is at least one first element selected of the group consisting of La, Ce, Nd and Sm. A is at least one second element selected of the group consisting of Mg, Ca, Sr, Ba, Na, K and Cs. B is at least one third element selected of the group consisting of Fe, Co, Ni and Mn. Wherein the third element is to oxidize NOx to form NO2.
Perovskites are also applied in other technical fields. US-A-5,447,705, for example, describes the use of specific catalysts of the composition LnxAt.yByO3 in the preparation of synthesis gas. x is between 0 and 10 and y is between 0 and 1. Ln is at least one element selected from the rare earths with the atomic numbers 57 through 71. A and B are metals that differ from each other selected of the groups IVb, Vb, VIb, VIIb and VHI.
Among the catalysts previously described, especially cobalt containing catalysts exhibit the disadvantage that they are very sensitive to contamination by sulphur. Further, these catalysts age particularly rapidly.
Another problem observed in association with a variety of catalysts so far proposed for the decomposition of N2O is the inhibition by the oxygen present in the product gas and exhaust gas respectively. Operating performance of these catalysts is only guaranteed when a reducing agent is present in the gas stream for the removal of the physically or chemically adsorbed oxides.
It was an object of the present invention to provide a catalyst for the decomposition of N2O. The catalyst was supposed to be particularly suitable for the use in the decomposition of N2O in the product gas of ammonia oxidation in nitric acid preparation.
The invention relates to a catalyst comprising a carrier in form of honeycomb and a Perovskite- type compound represented by the general formula (1)
M1M2 LxM3 XO3 (1)
wherein x ranges from 0.05 to 0.9, M1 is selected of the group consisting of La, Ce, Nd, Pr, Sm and combinations thereof, M2 is selected of the group consisting of Fe, Ni and combinations thereof, and M3 is selected of the group consisting of Cu, Co, Mn and combinations thereof.
The present invention also relates to a process for decomposing N2O wherein N2O is brought into contact with a Perovskite-type compound represented by the general formula (1)
M1M2 LxM3 XO3 (1)
wherein x ranges from 0.0 to 0.9, M1 is selected of the group consisting of La, Ce, Nd, Pr, Sm and combinations thereof, M2 is selected of the group consisting of Fe, Ni and combinations thereof, and M3 is selected of the group consisting of Cu, Co, Mn and combinations thereof.
In another embodiment the invention relates to a device for preparation of nitric acid comprising a Perovskite-type compound represented by the general formula (1)
M1M2 LxM^O3 (1)
wherein x ranges from 0.0 to 0.9, M1 is selected of the group consisting of La, Ce, Nd, Pr, Sm and combinations thereof, M2 is selected of the group consisting of Fe, Ni and combinations thereof, and M3 is selected of the group consisting of Cu, Co, Mn and combinations thereof, and a catalyst for ammonia oxidation.
The use of a Perovskite-type compound represented by the general formula (1)
wherein x ranges from 0.0 to 0.9, M1 is selected of the group consisting of La, Ce, Nd, Pr, Sm and combinations thereof, M2 is selected of the group consisting of Fe, Ni and combinations thereof, and M3 is selected of the group consisting of Cu, Co, Mn and combinations thereof, for the decomposition of N2O is also described.
Figure 1 shows the N2O decomposition rate and the activation energy of the process for LaMO3- Perovskites.
Compounds of the Perovskite type
The Perovskite-type compound has the following general formula (1)
x is at least 0.0, preferably at least 0.05, more preferably at least 0.1, even more preferably at least 0.15. x is at most 0.9, preferably at most 0.6, more preferably at most 0.4, even more preferably at most 0.25.
M1 is selected of the group consisting of La, Ce, Nd, Pr, Sm and combinations thereof. In one embodiment, M1 is preferably La. Alternatively, M1 is preferably a combination of the indicated lanthanides, for example a combination of 50 to 55 % by weight Ce, 25 to 30 % by weight La, 10 to 15 % by weight Nd, 5 to 10 % by weight Pr as well as 0 to 1 % by weight Sm, calculated as oxide respectively. In the following, a combination of lanthanides is abbreviated as Ln.
M2 is selected of the group consisting of Fe, Ni and combinations thereof.
M3 is selected of the group consisting of Cu, Co, Mn and combinations thereof. Preferred are Cu and Co, more preferred is Co.
In the case of M2 = Ni, M3 is preferably Cu and Co, more preferably Co. x ranges preferably from 0 to 0.4 or from 0.15 to 0.4.
In the case of M2 = Fe or the combination of Fe and Ni, M3 is preferably Cu. x ranges preferably from 0 to 0.4 or from 0.15 to 0.4.
Preferred compounds are:
M1FeO3
M'Feo.s.i.oCuo.a-o.oOa
In the formulas above, M1 is preferably La or Ln.
Although it is not desired to be bound by a particular theory, it is assumed that the incorporation of the element M3 into the Perovskite crystal structure results in alteration of the nature of the 3d cation in its charge distribution or the formation of oxygen/cation lattice vacancies, a crystallographic defect. Thereby a new surface species is formed which is involved in the catalytic reaction and requires different activation energy for the catalytic N2O decomposition which the special applicability of the compounds of the Perovskite type represented by the general formula (1) is based on.
According to the invention, the Perovskite-type compound can be used in different forms as a catalyst. The Perovskite-type compound can, for example, be used as such in form of regularly or irregularly shaped particles (powder, granulate, granules). Alternatively, the Perovskite-type compound is used in combination with a carrier. The carrier can have any known form. Thus, amongst others, granules, pearls or honeycomb carriers are possible. In one preferred embodiment, carriers in the shape of honeycomb are used. These offer a mostly approximately cylindrical outer shape, pervaded by a variety of parallel channels. Such carriers of the honeycomb type are known in the field of catalysis. The carrier itself consists mostly of oxidic material (e.g. cordierite) or metal. Both forms can be used according to the invention.
The Perovskite-type compound can be incorporated in the material of the carrier, the carrier can be impregnated with the Perovskite-type compound or the carrier can have a surface coating ("washcoat"), containing the Perovskite-type compound.
In the embodiment wherein the carrier has a surface coating containing the Perovskite-type compound the Perovskite-type compound can be applied to a carrier material contained in the surface coating.
The commonly used materials known in the art are suitable as carrier material. Preferably high- surface materials are used as carrier material. In the scope of this invention, materials are referred to as high-surface, the specific BET-surface of which being larger than 5 m2/g. Suitable carrier materials are for example titanium oxide, aluminium oxide, silicon oxide, cerium oxide, zirconium oxide, zeolite and mixtures or mixed oxides thereof. Preferably, the carrier material comprises aluminium oxide, as this can additionally slow down the aging of the catalyst.
A carrier provided with a surface coating can be produced in different ways. In a first approach the carrier can be provided and then a coating comprising carrier material and Perovskite-type compound can be applied. In a second approach the carrier can be provided, a coating comprising carrier material can be applied and then the Perovskite-type compound can be applied. Processes for performing these steps are known in the state of the art.
In the first approach, for example a dispersion of the Perovskite-type compound and the other coating components, including carrier material or precursors thereof, can be prepared. Here, the Perovskite-type compound can already be present on the carrier material or it can be present separately in the dispersion. The carrier can be immersed in said dispersion once or several times. Then, residual dispersion can, wherever necessary, be removed from the channels of the carrier and the catalyst can be completed, for example by drying and calcination.
In the second approach a dispersion of the coating components as above is described, however is provided without the Perovskite-type compound and the carrier coated as described. Then the coated carrier is impregnated with a precursor compound for the Perovskite-type compound. The precursor compound will then be converted to form the Perovskite-type compound.
It has been observed that depending on the type of carrier different Perovskite-type compounds can preferably be used. In the embodiment wherein the carrier has a surface coating containing the Perovskite-type compound, the Perovskite-type compound preferably has the formulas M1FeCS-I oCUo2-OoO3 and M1FeO
more preferably M1FeO 4NiO6Os); wherein M1 is more preferably La. Surprisingly, these compounds are characterized a by high resistance towards modifications with components of the carrier material, such as the formation of less active spinels. The activity, particularly of the Perovskite-type compound with the formula LaFeo.8-i.oCuo.2-o.o03, is hardly influenced by changes in the contents of oxygen and water in the gas stream. An influence on selectivity in the presence of NO/NO2 in the gas stream is not detectable.
Alternatively, the Perovskite-type compound is incorporated into the material of the carrier. The carrier preferably comprises the Perovskite-type compound in an amount of 50 to 90 % by weight, preferably of 55 % by weight to 70 % by weight, referring to the total weight of the carrier. Besides the Perovskite-type compound the carrier can additionally contain common components. Among them are oxidic materials that are, for example, resistant up to a temperature of 1200 0C. Examples of such compounds are cordierite, alumina, graphite, mullite, aluminium oxide, zirconium oxide, zirconium mullite, barium titanate, titanium oxide, silicon carbide and silicon nitrite. In a particularly preferred embodiment, the carrier comprises cordierite besides the compounds of the Perovskite type, preferably in an amount of 0 % by weight to 50 % by weight, preferably of 0 % by weight to 15 % by weight, alumina in an amount of 0 % by weight to 50 % by weight, particularly preferred 0 % by weight to 30 % by weight, and Al2O3 in an amount of 0 % by weight to 50 % by weight, particularly preferred 10 % by weight to 30 % by weight. Preferably, extrudates contain 25 to 30 % by weight Al2O3, 8 to 10 % by weight cordierite and about 5 % by weight graphite.
In one embodiment the carrier consists of the Perovskite-type compound. In one preferred embodiment, the Perovskite-type compound has the formula M1NiO 9-07CoO i-O 3O3, preferably M1Ni08Co02O3 wherein M1 is preferably La. Surprisingly, these compounds show a low activation energy of about 30 kcal/mol for the observed N2O decomposition, allowing a universal use in a wide temperature range. Particularly in the typical temperature range from 850 to 900 0C for the decomposition of N2O in nitric acid preparation, a doubling of the N2O decomposition is found. Simultaneously, the examinations show a linear relationship of the
decomposition efficiency with the amount of catalyst used in said temperature range. An influence on selectivity in the presence of NO/NO2 in the test gas is not detectable.
Table 1: Reaction rate W, N2O decomposition X and activation energy EA at the N2O decomposition for LaMC^ catalysts (at 900 °C). The N2O decomposition X is defined as the quotient of reacted amount of N2O to supplied amount of N2O.
In the case of extrudates, preferred compounds of the Perovskite type are M1FeOg-I oCUo2-OoO3 and M1Fe03-OgN^-01O3 (preferably M1Fe04-OsNiOo-OaO3, more preferably M1FeO8Ni02O3). In these embodiments, M1 is preferably Ln. Carriers comprising respective extrudates, have a surprisingly high porosity. Furthermore, the formation of NiFe2O4 or CuFe2O4 spinels seems to significantly increase the catalytic activity with regard to the N2O decomposition in these compounds. Besides, a minor dependence of the N2O decomposition activity of varying contents of water, oxygen as well as the presence of N0/N02 in the reaction gas is observed.
In extrudates LaFeO3 has also proven to be particularly effective. This Perovskite-type compound has a high activity in N2O decomposition.
Process for decomposing N2O
Furthermore the present invention relates to a process for decomposing N2O wherein N2O is brought into contact with the Perovskite-type compound. In the decomposition basically N2 and O2 are formed.
The conditions where the Perovskite-type compound is brought into contact with the N2O are not particularly limited. For example, the reaction temperature can be 800 to 1200 0C. The amount
of Perov ski te- type compound used conforms to the application and can suitably be appreciated by one with ordinary skill in the art. The contact time between catalyst and N2O also depends on the application and is preferably more than 0.02 sec.
As the catalyst according to the invention can also be used when the N2O containing gas stream contains water, oxygen, NO or NOx, it can be used in a wide variety of applications wherein N2O is to be decomposed. The process according to the invention is particularly suitable for the decomposition of N2O in the product gas of the ammonia oxidation in nitric acid preparation.
Device for preparation of nitric acid
The present invention also relates to a device for preparation of nitric acid comprising a Perovskite-type compound and a catalyst for ammonia oxidation. Devices for the preparation of nitric acid are known in the art and are, for example, described in Kirk-Othmer, Encyclopedia of Chemical Technology, Vol. 17, 4th edition (1996), pages 84 to 96. The device according to the invention differs from the previous devices in that additionally the Perovskite-type compound is used for the decomposition of N2O. Thereby emissions of harmful N2O can be reduced.
In one embodiment the Perovskite-type compound is downstream in the direction of flow to the catalyst for the oxidation of ammonia. Preferably only after the decomposition of N2O does the absorption of nitrogen oxides in water take place in the device according to the invention.
The Perovskite-type compound can be present in one of the above described catalyst forms. It is, however, preferably used in combination with a carrier in the shape of honeycomb.
Such a honeycomb carrier with the Perovskite-type compound represented by the general formula (1) is, for example, placed in the reactor for catalytic ammonia oxidation on a carrier in the form of a grid, lattice or in a basket. If honeycomb carriers are used, one carrier or several carriers can be used. In such a device, the honeycomb carrier can take over the carrier function for the imposed precious metal catalyst and the precious metal recovery system, possibly located directly downstream. In the device according to the invention precious metal catalyst and precious metal recovery system can be separated from the honeycomb carrier by one or more separator meshes, for example made of non-precious metal. Because of the device according to
the invention, a uniform flow through the precious metal catalyst and the carrier in the shape of honeycomb is achieved.
The device according to the invention is advantageous, because the honeycomb carrier allows for a uniform flow at minimal pressure loss. An adaptation to the specific operating conditions of a nitric acid reactor and the N2O contents in the process gas is readily possible by respective modifications of the channel openings, their number and wall thickness.
Preparation of the compounds of the Perovskite type
The preparation of the compounds of the Perovskite type is not particularly limited and any process for the preparation of compounds of the Perovskite type known in the art can be used. Among these processes are coprecipitation, impregnation, sol-gel techniques and mechanical mixing of oxides or precursors of oxides, followed by calcination.
In the following several processes which have been used for the preparation of the compounds of the Perovskite type used in the examples, are described for illustration.
(i) Pechini process
Compounds of the Perovskite type are produced by the Pechini process [M. P. Pechini, US-A- 3,330,697]. Herein, citric acid and ethylene glycol are added to a solution of the accordingly proportioned nitrate salts saturated at room temperature. The solution is evaporated at 80 to 100 °C. After tempering at 200 to 250 °C an amorphous Perovskite precursor will be formed. For formation of the Perovskite, the sample is calcined for 4 hours at 700 to 900 °C.
(ii) Mechanochemical process
For the preparation of the compounds of the Perovskite type commercially available transition metal oxides, such as Ot-Fe2O3, CoO, CuO, MnO, NiO and the respective carbonates of the lanthanides are mixed. The mixed oxides of the rare earth and transition metals are obtained by mixing for example Ln2(CO3)3 / Fe2O3 in a weight ratio of 4.5 : 1.0. Fe2O3 can also be replaced by one or more further transition metal oxides. The mixture will then be fed to a disintegrator for
several times. After tempering at 700 to 900 0C over a period of 4 hours the resulting mixture is repeatedly triturated in the disintegrator.
Preparation of impregnated carriers
(i) Pechini process
Citric acid and ethylene glycol are added to a solution of the accordingly proportioned nitrate salts, saturated at room temperature. A commercially available honeycomb carrier based on cordierite is immersed in the solution for 5 to 10 min, blown off with air and dried at air at room temperature. Calcination will then be conducted at temperatures between 700 and 900 °C over a period of 4 hours.
(ii) Pasting process
A Perovskite-type compound is added to a cordierite or Al2O3 paste for the preparation of a honeycomb carrier. Alternatively, a solution of accordingly proportioned nitrate salts of the Perovskite-type compound can be added to the paste. Besides cordierite and Al2O3 respectively, the paste can contain an aqueous solution of methyl cellulose. As further components, alumina, talc and 3d oxides can be added in the required ratios. The paste is mixed in a mixer for a period of 40 min. The resulting paste has a humidity of 20 to 30 %. It will then be extruded through a pressure template to form a mould. The resulting monoliths are hardened at room temperature and dried at 300 to 400 °C over a period of 4 hours. Afterwards calcination is conducted at a temperature of 1000 to 1250 0C over a period of 4 to 5 hours.
Preparation of Perovskite-containing carriers
Citric acid and ethylene glycol are added to a solution of the accordingly proportioned nitrate salts, saturated at room temperature, and said solution is evaporated at 80 to 100 0C. In this step, polymerized metal ether complexes form. After tempering at 200 to 250 °C the organic residue will be incinerated and an amorphous precursor of the Perovskite has formed. For obtaining the Perovskite-type compound, the amorphous precursor is tempered at 700 to 900 °C over a period of 4 hours.
For compounds represented by the formula Ln(FeiNi)1-xCuxO3, commercially available transition metal oxides Ot-Fe2O3, NiO and CuO as well as carbonates of mixed lanthanides (Ln) are used as starting material. The composition of these mixed lanthanides is 50 to 55 % by weight Ce, 25 to 30 % by weight La, 10 to 15 % by weight Nd, 5 to 10 % by weight Pr as well as 0 to 1 % by weight Sm, stated as their oxides CeO2, La2O3, Nd2O3, Pr6O11 and Sm2O3.
A mixture of the rare earth and transition metals is achieved by mixing 3.5 kg Ln2(CO3)3 with 1.3 kg Fe2O3 and CuO or NiO respectively. After mixing the mixture will be tempered at 700 to 900 °C over a period of 4 hours to obtain the Perovskite-type compound.
For obtaining a mouldable paste the Perovskite-type compound is plasticized with a binder based on Al2O3 (Al2O3 • n H2O) or alumina (Al2O3 / 20 - 25 % by weight, SiO2 / 55 - 60 % by weight, H2O / 10 - 15 % by weight, rest admixtures) (as well as a peptisizing agent, for example an aqueous solution of different acids, such as nitric, oxalic and acetic acid). For the enhancement of the rheology of the paste ethylene glycol is added. Further, cordierite particles (2 MgO • 2 Al2O2 • 5 SiO2) with a particle size of less than 0.5 mm and graphite can be added. Such components will increase the thermal shock stability and the porosity of the catalyst material respectively. The mixture is treated mechanically over a period of 10 min in a planetary ball mill and will then be extruded to form a honeycomb carrier. After drying at room temperature, the honeycomb carrier is calcined at 900 to 1150 0C over a period of 4 hours.
The described compounds of the Perovskite type represent a significant progress in N2O decomposition as they have a high thermal shock resistance. This is of particular importance for a use in the Ostwald process as excessive temperature differences occur especially during starting up and shutting down the reactor. Furthermore, the compounds of the Perovskite type have a high aging stability even at high temperatures, as they prevail, for example, in the product gas stream of nitric acid preparation. They can also be used in applications wherein the gas stream contains sulphur and sulphur containing compounds, oxygen, water, NO or NOx besides N2O.
EXAMPLES
The invention is now illustrated by means of the following examples. It should not, however, be considered as being limited to these preferred embodiments.
Experimental assembly of the test reactor
The catalytic decomposition of N2O is conducted in a U-shaped fused quartz flow reactor with an internal diameter of 11.4 mm at ambient pressure. For uniform tempering, the reactor is placed in an electrically heated sand bath.
Measurement and regulation of the reactor temperature takes place on the external wall of the reactor. Additionally, the catalyst temperature is taken by a temperature measurement in one of the honeycomb channels. The flow rates of the gas mixtures are set in a range of 0.5 to 3.2 1/min by mass flow controllers. Steam is added by a saturator at given temperature. In order to exclude the formation of potential condensates all elements and sampling systems flown through by gas are heat insulated and heated.
Example 1
A bulk of inactive fused quartz granules (1 to 2 mm in diameter, total mass of 1 g) is filled into the test reactor. Hereto a catalyst bed of 5 to 20 mg of particles of the Perovskite-type compound with a particle size of 0.25 to 0.50 mm is placed. The BET-surface of the Perovskite-type compound varies from 1 to 10 m2/g. Each measurement is conducted at constant temperature in stationary state. For correction of the N2O homogenous decomposition comparable measurement without catalyst will be conducted. For comparison the results, besides the absolute reaction of N2O, are applied to the reaction rate W in mole N2O / m2s.
Table 2: Experimental conditions
Table 3: Activity of the compounds of the Perovskite type
The highest activities for the decomposition of N2O have been found for Co- and Ni-comprising Perovskites, particularly for Perovskites containing both elements.
The catalytic properties of the examined Perovskites show a special dependency on the nature of the 3d cation, its charge and coordination. By additional elements M3, these properties can be modified, an effect which is probably due to point or crystallographic defects wherein the introduction of an element M3 with several valences results in a change of the cation charge or in the formation of oxygen cation valences.
Example 2
In this example, a carrier in the shape of honeycomb which is impregnated with the Perovskite- type compound is examined.
For the examinations, a cordierite carrier with a surface area of 35 m2/g and a pore volume of 0.4 cm3/g is selected. The carrier has a honeycomb structure with a hexagonal base area as well as isosceles, triangular channel openings having a side length of 2.5 mm and a wall thickness of 0.4 mm. For the examinations such carriers with a diameter of 9 to 10 mm are used. The results are set forth in table 5 to 7.
Table 4: Experimental conditions
The weight ratio is related to the total weight of the honeycomb carrier.
Table 6: N2O decomposition depending on oxygen content (0.13 % N2O)
Example 3
Carriers in the shape of honeycomb containing a Perovskite-comprising extrudate are examined. Two different geometries are used for the examination and testing. A first series comprises hexagonal prisms with a side length of 6.0 cm and a triangular channel geometry with a side length of 2.5 mm and a wall thickness of 0.4 mm. A second series comprises hexagonal prisms with a side length of 2.8 cm, with a triangular channel geometry with a side length of 1.6 mm and a wall thickness of 0.6 mm. The samples were cut out of the produced honeycomb carriers respectively. The form was chosen in such way that the samples fit into the test reactor.
The activity of the catalyst is determined for a temperature range of 800 to 900 0C. A standard gas composition consists of 0.15 % N2O, 3 % O2 and 3 % H2O, balance helium. For the examination of the oxygen influence with reference to a possible inhibition of the catalyst, a gas composition of 0.13 % N2O, 7 % O2 and 3 % H2O, balance helium, is used. For examinations of the influence of H2O on the N2O decomposition, the portion of steam is increased to 10 to 12 %. All listed values are corrected for the value of the homogenous high temperature self- decomposition of N2O.
Table 8: Experimental conditions
Table 9: Experimental data
Example 4
In order to examine the Effect of water concentration in the gas on the N2O decomposition, the H2O saturator is operated at different temperatures.
Table 10: Effect of water concentration on N2O decomposition (XN2O), sample 57 % LnFeO3 + 28.6 % Al2O3 + 9.5 % cordierite + 4.9 % graphite; height of the monolith = 12.0 mm; temperature 900 °C
Table 11: Effect of water concentration on N2O decomposition (XN2O). sample 57 % LnFe08Cu02O3+ 30 % Al2O3 + 10 % cordierite + 5 % alumino-silicate fibres; height of the monolith = 6.60 mm; temperature 900 0C
Table 12; Effect of water concentration on N2O decomposition (XN2O), sample 57 % LnFe08Ni02O3+ 28.6 % Al2O3 + 9.5 % cordierite + 4.9 % graphite; height of the monolith = 6.60 mm; temperature 900 °C
Table 14: Effect of oxygen concentration on N2O decomposition, sample 57 % LnFeO3+ 28.6 % A All22OO33 ++ 99..55 %% ccoorrddierite + 4.9 % graphite; height of the monolith = 6.6 mm; C°N2o = 0.118 %; temperature 900 0C
Example 15
In an industrial reactor for nitric acid production an extruded honeycomb carrier with a Perovskite-type compound LaFeO3 is set onto the grid of a basket. For spacing of the precious metal catalyst and the platinum recovery system two base Megapyr separator meshes are used.
Table 15: Geometry of the honeycomb carrier
Table 16: Industrial operating conditions
As a result the amount of N2O in the exhaust gas was reduced by 65.8 % from 491 ppm to 168 ppm.
Claims
1. Catalyst comprising a carrier in the shape of honeycomb and a Perovskite-type compound represented by the general formula (1)
wherein x ranges from 0.05 to 0.9, M1 is selected of the group consisting of La, Ce, Nd, Pr, Sm and combinations thereof, M2 is selected of the group consisting of Fe, Ni and combinations thereof, and M3 is selected of the group consisting of Cu, Co, Mn and combinations thereof.
2. Catalyst according to claim 1 wherein M1 is La.
3. Catalyst according to any of claims 1 or 2 wherein x ranges from 0.05 to 0.8.
4. Catalyst according to any of claims 1 to 3 wherein the carrier is an extrudate comprising the Perovskite-type compound.
5. Catalyst according to any of claims 1 to 3 wherein the carrier is impregnated with the Perovskite-type compound.
6. Catalyst according to any of claims 1 to 3 wherein the Perovskite-type compound is present on a carrier material and the carrier is coated with the carrier material.
7. Process for decomposing nitrous oxide wherein nitrous oxide is brought into contact with a Perovskite-type compound represented by the general formula (1)
M'M2,.XM3 XO3 (1)
wherein x ranges from 0.0 to 0.9, M1 is selected of the group consisting of La, Ce, Nd, Pr, Sm and combinations thereof, M2 is selected of the group consisting of Fe, Ni and combinations thereof, and M3 is selected of the group consisting of Cu, Co, Mn and combinations thereof.
8. Process according to claim 7 wherein the process is conducted in the presence of oxygen.
9. Process according to claim 7 or 8 wherein the nitrous oxide is present in the product gas of the ammonia oxidation.
10. Process according to claim 9 wherein the product gas is brought into contact with the Perovskite-type compound at a temperature of 800 °C to 1200 0C.
11. Device for preparation of nitric acid comprising a Perovskite-type compound represented by the general formula (1)
wherein x ranges from 0.0 to 0.9, M1 is selected of the group consisting of La, Ce, Nd, Pr, Sm and combinations thereof, M2 is selected of the group consisting of Fe, Ni and combinations thereof, and M3 is selected of the group consisting of Cu, Co, Mn and combinations thereof, and a catalyst for ammonia oxidation.
12. Device according to claim 11 wherein the Perovskite-type compound is downstream in the direction of flow of the product gas to the catalyst for ammonia oxidation.
13. Device according to claim 11, further comprising one or several separator meshes wherein the catalyst for ammonia oxidation, the separator mesh(es) and the Perovskite- type compound are arranged in the given order in the direction of flow of the product gas.
14. Process for the preparation of nitric acid by using the device according to any of claims 11 to 13.
15. Use of a Perovskite-type compound represented by the general formula (1)
M1M2 LxM^O3 (1) wherein x ranges from 0.0 to 0.9, M1 is selected of the group consisting of La, Ce, Nd, Pr, Sm and combinations thereof, M2 is selected of the group consisting of Fe, Ni and combinations thereof, and M3 is selected of the group consisting of Cu, Co, Mn and combinations thereof, for the decomposition of nitrous oxide.
16. Use according to claim 15 wherein the nitrous oxide is present in the product gas of the ammonia oxidation in nitric acid preparation.
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| RU2006107288/04A RU2397810C2 (en) | 2006-03-10 | 2006-03-10 | Catalyst and method of decomposing dinitrogen monoxide and method and device for producing nitric acid |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2145663A1 (en) | 2008-07-16 | 2010-01-20 | Umicore AG & Co. KG | Catalyst for converting nitrous oxide and its application in industrial nitric acid production |
| DE102010005105A1 (en) | 2010-01-19 | 2011-07-21 | Umicore AG & Co. KG, 63457 | catalyst |
| JP2013230471A (en) * | 2008-10-03 | 2013-11-14 | Rhodia Operations | Method of decomposing n2o using catalyst based on cerium lanthanum oxide |
| US9616413B2 (en) | 2007-10-24 | 2017-04-11 | Yara International Asa | Catalyst for production of nitric oxide |
| CZ307189B6 (en) * | 2017-01-30 | 2018-03-07 | Ústav fyzikální chemie J. Heyrovského AV ČR, v. v. i. | A method of production of catalysts of a perovskite structure, catalysts perovskite structure and their use for high temperature decomposition of N2O |
| CN114768861A (en) * | 2022-04-02 | 2022-07-22 | 潍柴动力股份有限公司 | Oxide-molecular sieve composite catalyst and preparation method and application thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4812300A (en) * | 1987-07-13 | 1989-03-14 | Sri-International | Selective perovskite catalysts to oxidize ammonia to nitric oxide |
| EP0468127A2 (en) * | 1990-07-26 | 1992-01-29 | Peking University | Perovskite-type rare earth complex oxide combustion catalysts |
| WO1997037760A1 (en) * | 1996-04-10 | 1997-10-16 | Catalytic Solutions, Inc. | Perovskite-type metal oxide compounds |
| WO2004096703A2 (en) * | 2003-04-29 | 2004-11-11 | Johnson Matthey Plc | Ammonia oxidation process |
-
2006
- 2006-03-10 RU RU2006107288/04A patent/RU2397810C2/en active
-
2007
- 2007-02-16 WO PCT/EP2007/001381 patent/WO2007104403A1/en active Application Filing
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4812300A (en) * | 1987-07-13 | 1989-03-14 | Sri-International | Selective perovskite catalysts to oxidize ammonia to nitric oxide |
| EP0468127A2 (en) * | 1990-07-26 | 1992-01-29 | Peking University | Perovskite-type rare earth complex oxide combustion catalysts |
| WO1997037760A1 (en) * | 1996-04-10 | 1997-10-16 | Catalytic Solutions, Inc. | Perovskite-type metal oxide compounds |
| WO2004096703A2 (en) * | 2003-04-29 | 2004-11-11 | Johnson Matthey Plc | Ammonia oxidation process |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9616413B2 (en) | 2007-10-24 | 2017-04-11 | Yara International Asa | Catalyst for production of nitric oxide |
| EP2145663A1 (en) | 2008-07-16 | 2010-01-20 | Umicore AG & Co. KG | Catalyst for converting nitrous oxide and its application in industrial nitric acid production |
| WO2010007087A1 (en) * | 2008-07-16 | 2010-01-21 | Umicore Ag & Co. Kg | Catalyst for reacting dinitrogen monoxide and use thereof in industrial nitric acid production |
| JP2013230471A (en) * | 2008-10-03 | 2013-11-14 | Rhodia Operations | Method of decomposing n2o using catalyst based on cerium lanthanum oxide |
| DE102010005105A1 (en) | 2010-01-19 | 2011-07-21 | Umicore AG & Co. KG, 63457 | catalyst |
| WO2011089124A2 (en) | 2010-01-19 | 2011-07-28 | Umicore Ag & Co. Kg | Catalyst |
| CZ307189B6 (en) * | 2017-01-30 | 2018-03-07 | Ústav fyzikální chemie J. Heyrovského AV ČR, v. v. i. | A method of production of catalysts of a perovskite structure, catalysts perovskite structure and their use for high temperature decomposition of N2O |
| CN114768861A (en) * | 2022-04-02 | 2022-07-22 | 潍柴动力股份有限公司 | Oxide-molecular sieve composite catalyst and preparation method and application thereof |
| CN114768861B (en) * | 2022-04-02 | 2023-12-15 | 潍柴动力股份有限公司 | Oxide-molecular sieve composite catalyst and preparation method and application thereof |
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| RU2397810C2 (en) | 2010-08-27 |
| RU2006107288A (en) | 2007-09-20 |
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