CN118059924B - Alkali metal-based catalyst and preparation method and application thereof - Google Patents
Alkali metal-based catalyst and preparation method and application thereof Download PDFInfo
- Publication number
- CN118059924B CN118059924B CN202410476263.3A CN202410476263A CN118059924B CN 118059924 B CN118059924 B CN 118059924B CN 202410476263 A CN202410476263 A CN 202410476263A CN 118059924 B CN118059924 B CN 118059924B
- Authority
- CN
- China
- Prior art keywords
- alkali metal
- molecular sieve
- based catalyst
- sod
- carbon dioxide
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000003054 catalyst Substances 0.000 title claims abstract description 120
- 229910052783 alkali metal Inorganic materials 0.000 title claims abstract description 77
- 150000001340 alkali metals Chemical class 0.000 title claims abstract description 75
- 238000002360 preparation method Methods 0.000 title claims abstract description 21
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims abstract description 155
- 238000006243 chemical reaction Methods 0.000 claims abstract description 90
- 239000002808 molecular sieve Substances 0.000 claims abstract description 85
- URGAHOPLAPQHLN-UHFFFAOYSA-N sodium aluminosilicate Chemical compound [Na+].[Al+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O URGAHOPLAPQHLN-UHFFFAOYSA-N 0.000 claims abstract description 85
- 239000001569 carbon dioxide Substances 0.000 claims abstract description 77
- 229910002092 carbon dioxide Inorganic materials 0.000 claims abstract description 77
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims abstract description 51
- 229910002091 carbon monoxide Inorganic materials 0.000 claims abstract description 51
- 229910001413 alkali metal ion Inorganic materials 0.000 claims abstract description 39
- 239000002105 nanoparticle Substances 0.000 claims abstract description 37
- 229910052739 hydrogen Inorganic materials 0.000 claims abstract description 24
- 239000001257 hydrogen Substances 0.000 claims abstract description 22
- 229910000314 transition metal oxide Inorganic materials 0.000 claims abstract description 22
- QPLDLSVMHZLSFG-UHFFFAOYSA-N Copper oxide Chemical compound [Cu]=O QPLDLSVMHZLSFG-UHFFFAOYSA-N 0.000 claims description 27
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 27
- 239000007789 gas Substances 0.000 claims description 21
- 238000005984 hydrogenation reaction Methods 0.000 claims description 21
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 18
- 239000000243 solution Substances 0.000 claims description 17
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 16
- 238000000034 method Methods 0.000 claims description 16
- 239000011734 sodium Substances 0.000 claims description 15
- 238000005406 washing Methods 0.000 claims description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 12
- 238000001035 drying Methods 0.000 claims description 11
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims description 9
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims description 9
- 229910052708 sodium Inorganic materials 0.000 claims description 9
- 235000011121 sodium hydroxide Nutrition 0.000 claims description 9
- 239000004115 Sodium Silicate Substances 0.000 claims description 8
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 claims description 8
- 229910052911 sodium silicate Inorganic materials 0.000 claims description 8
- 229910052723 transition metal Inorganic materials 0.000 claims description 7
- 150000003624 transition metals Chemical class 0.000 claims description 7
- 238000000227 grinding Methods 0.000 claims description 6
- 238000002156 mixing Methods 0.000 claims description 6
- 239000002245 particle Substances 0.000 claims description 5
- 230000008569 process Effects 0.000 claims description 5
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 claims description 4
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 4
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 claims description 4
- 230000032683 aging Effects 0.000 claims description 4
- 229910052782 aluminium Inorganic materials 0.000 claims description 4
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 4
- AMWRITDGCCNYAT-UHFFFAOYSA-L hydroxy(oxo)manganese;manganese Chemical compound [Mn].O[Mn]=O.O[Mn]=O AMWRITDGCCNYAT-UHFFFAOYSA-L 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 claims description 4
- 239000012266 salt solution Substances 0.000 claims description 4
- 229910052710 silicon Inorganic materials 0.000 claims description 4
- 239000010703 silicon Substances 0.000 claims description 4
- 229910000029 sodium carbonate Inorganic materials 0.000 claims description 4
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 claims description 3
- 239000005751 Copper oxide Substances 0.000 claims description 3
- 235000011114 ammonium hydroxide Nutrition 0.000 claims description 3
- 238000000498 ball milling Methods 0.000 claims description 3
- -1 cesium ions Chemical class 0.000 claims description 3
- 229910000431 copper oxide Inorganic materials 0.000 claims description 3
- ATRRKUHOCOJYRX-UHFFFAOYSA-N Ammonium bicarbonate Chemical compound [NH4+].OC([O-])=O ATRRKUHOCOJYRX-UHFFFAOYSA-N 0.000 claims description 2
- 229910000013 Ammonium bicarbonate Inorganic materials 0.000 claims description 2
- BOTDANWDWHJENH-UHFFFAOYSA-N Tetraethyl orthosilicate Chemical compound CCO[Si](OCC)(OCC)OCC BOTDANWDWHJENH-UHFFFAOYSA-N 0.000 claims description 2
- 150000008044 alkali metal hydroxides Chemical class 0.000 claims description 2
- 229910000272 alkali metal oxide Inorganic materials 0.000 claims description 2
- WNROFYMDJYEPJX-UHFFFAOYSA-K aluminium hydroxide Chemical compound [OH-].[OH-].[OH-].[Al+3] WNROFYMDJYEPJX-UHFFFAOYSA-K 0.000 claims description 2
- SMZOGRDCAXLAAR-UHFFFAOYSA-N aluminium isopropoxide Chemical compound [Al+3].CC(C)[O-].CC(C)[O-].CC(C)[O-] SMZOGRDCAXLAAR-UHFFFAOYSA-N 0.000 claims description 2
- 235000012538 ammonium bicarbonate Nutrition 0.000 claims description 2
- 239000001099 ammonium carbonate Substances 0.000 claims description 2
- 229910000428 cobalt oxide Inorganic materials 0.000 claims description 2
- IVMYJDGYRUAWML-UHFFFAOYSA-N cobalt(ii) oxide Chemical compound [Co]=O IVMYJDGYRUAWML-UHFFFAOYSA-N 0.000 claims description 2
- 229910021485 fumed silica Inorganic materials 0.000 claims description 2
- 229910000480 nickel oxide Inorganic materials 0.000 claims description 2
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 claims description 2
- GNRSAWUEBMWBQH-UHFFFAOYSA-N oxonickel Chemical compound [Ni]=O GNRSAWUEBMWBQH-UHFFFAOYSA-N 0.000 claims description 2
- 229910001414 potassium ion Inorganic materials 0.000 claims description 2
- 229910001419 rubidium ion Inorganic materials 0.000 claims description 2
- 229910002027 silica gel Inorganic materials 0.000 claims description 2
- 239000000741 silica gel Substances 0.000 claims description 2
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 claims description 2
- 235000017550 sodium carbonate Nutrition 0.000 claims description 2
- 229910001415 sodium ion Inorganic materials 0.000 claims description 2
- 238000005507 spraying Methods 0.000 claims description 2
- 239000011787 zinc oxide Substances 0.000 claims description 2
- 229910052792 caesium Inorganic materials 0.000 claims 1
- 230000004913 activation Effects 0.000 abstract description 10
- 238000001179 sorption measurement Methods 0.000 abstract description 6
- 230000002035 prolonged effect Effects 0.000 abstract description 2
- 125000004435 hydrogen atom Chemical class [H]* 0.000 abstract 1
- 238000006722 reduction reaction Methods 0.000 description 25
- 230000009467 reduction Effects 0.000 description 24
- 238000012360 testing method Methods 0.000 description 20
- 230000000052 comparative effect Effects 0.000 description 18
- 239000010949 copper Substances 0.000 description 18
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 12
- 238000006555 catalytic reaction Methods 0.000 description 9
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 8
- 230000003197 catalytic effect Effects 0.000 description 6
- 229910052681 coesite Inorganic materials 0.000 description 6
- 229910052906 cristobalite Inorganic materials 0.000 description 6
- 239000000499 gel Substances 0.000 description 6
- 239000000377 silicon dioxide Substances 0.000 description 6
- 229910052682 stishovite Inorganic materials 0.000 description 6
- 229910052905 tridymite Inorganic materials 0.000 description 6
- 229910021642 ultra pure water Inorganic materials 0.000 description 6
- 239000012498 ultrapure water Substances 0.000 description 6
- 239000008367 deionised water Substances 0.000 description 5
- 229910021641 deionized water Inorganic materials 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 5
- 229910003455 mixed metal oxide Inorganic materials 0.000 description 5
- 239000004570 mortar (masonry) Substances 0.000 description 5
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 4
- 230000003213 activating effect Effects 0.000 description 4
- 230000008859 change Effects 0.000 description 4
- 229910052802 copper Inorganic materials 0.000 description 4
- XTVVROIMIGLXTD-UHFFFAOYSA-N copper(II) nitrate Chemical compound [Cu+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O XTVVROIMIGLXTD-UHFFFAOYSA-N 0.000 description 4
- 230000007423 decrease Effects 0.000 description 4
- 239000000543 intermediate Substances 0.000 description 4
- 229910044991 metal oxide Inorganic materials 0.000 description 4
- 150000004706 metal oxides Chemical class 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- 238000002441 X-ray diffraction Methods 0.000 description 3
- 230000008901 benefit Effects 0.000 description 3
- 239000006227 byproduct Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 150000002431 hydrogen Chemical class 0.000 description 3
- 238000009776 industrial production Methods 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 150000003839 salts Chemical class 0.000 description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 2
- 239000003513 alkali Substances 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 150000001722 carbon compounds Chemical class 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 239000002923 metal particle Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000007086 side reaction Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000001308 synthesis method Methods 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- ONDPHDOFVYQSGI-UHFFFAOYSA-N zinc nitrate Chemical compound [Zn+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O ONDPHDOFVYQSGI-UHFFFAOYSA-N 0.000 description 2
- BNGXYYYYKUGPPF-UHFFFAOYSA-M (3-methylphenyl)methyl-triphenylphosphanium;chloride Chemical compound [Cl-].CC1=CC=CC(C[P+](C=2C=CC=CC=2)(C=2C=CC=CC=2)C=2C=CC=CC=2)=C1 BNGXYYYYKUGPPF-UHFFFAOYSA-M 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- BDAGIHXWWSANSR-UHFFFAOYSA-M Formate Chemical compound [O-]C=O BDAGIHXWWSANSR-UHFFFAOYSA-M 0.000 description 1
- 229910002651 NO3 Inorganic materials 0.000 description 1
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 1
- NPYPAHLBTDXSSS-UHFFFAOYSA-N Potassium ion Chemical compound [K+] NPYPAHLBTDXSSS-UHFFFAOYSA-N 0.000 description 1
- FKNQFGJONOIPTF-UHFFFAOYSA-N Sodium cation Chemical compound [Na+] FKNQFGJONOIPTF-UHFFFAOYSA-N 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 238000004220 aggregation Methods 0.000 description 1
- QGZKDVFQNNGYKY-UHFFFAOYSA-N ammonia Natural products N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- QZPSXPBJTPJTSZ-UHFFFAOYSA-N aqua regia Chemical compound Cl.O[N+]([O-])=O QZPSXPBJTPJTSZ-UHFFFAOYSA-N 0.000 description 1
- 125000004429 atom Chemical group 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- NCMHKCKGHRPLCM-UHFFFAOYSA-N caesium(1+) Chemical compound [Cs+] NCMHKCKGHRPLCM-UHFFFAOYSA-N 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000003763 carbonization Methods 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- 238000001311 chemical methods and process Methods 0.000 description 1
- 238000005229 chemical vapour deposition Methods 0.000 description 1
- 239000003426 co-catalyst Substances 0.000 description 1
- 238000000975 co-precipitation Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- FTXJFNVGIDRLEM-UHFFFAOYSA-N copper;dinitrate;hexahydrate Chemical compound O.O.O.O.O.O.[Cu+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O FTXJFNVGIDRLEM-UHFFFAOYSA-N 0.000 description 1
- 230000009849 deactivation Effects 0.000 description 1
- 230000003247 decreasing effect 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
- 238000010586 diagram Methods 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 239000011363 dried mixture Substances 0.000 description 1
- 238000000921 elemental analysis Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000005431 greenhouse gas Substances 0.000 description 1
- 238000005470 impregnation Methods 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 230000002779 inactivation Effects 0.000 description 1
- 238000009616 inductively coupled plasma Methods 0.000 description 1
- 238000002354 inductively-coupled plasma atomic emission spectroscopy Methods 0.000 description 1
- 238000005342 ion exchange Methods 0.000 description 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 1
- 238000011031 large-scale manufacturing process Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 229910000510 noble metal Inorganic materials 0.000 description 1
- 230000002572 peristaltic effect Effects 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 238000007873 sieving Methods 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 239000008247 solid mixture Substances 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts
Landscapes
- Catalysts (AREA)
Abstract
The invention relates to an alkali metal-based catalyst, a preparation method and application thereof, and belongs to the technical field of catalysts. The alkali metal-based catalyst comprises transition metal oxide nano particles and a sod molecular sieve; and alkali metal ions are encapsulated in the sod molecular sieve. The alkali metal-based catalyst stabilizes alkali metal ions through the sod cage, and the alkali metal ions enhance the adsorption and activation of carbon dioxide; the transition metal oxide nano particles activate hydrogen, so that the alkali metal-based catalyst has high carbon dioxide conversion rate and carbon monoxide selectivity, and the service life of the alkali metal-based catalyst is also greatly prolonged.
Description
Technical Field
The invention belongs to the technical field of catalysts, and particularly relates to an alkali metal-based catalyst, and a preparation method and application thereof.
Background
Carbon dioxide (CO 2) is a greenhouse gas whose emissions have a significant impact on global climate change. Currently, the production of synthetic fuels and most chemicals in the chemical industry relies mainly on synthesis gas (a mixture of CO and H 2). The process of converting CO 2 into carbon monoxide (CO) can be connected with the existing industrial catalysis, no special transformation is needed, and the method is simple and easy to implement and is an important link of carbon circulation. The reaction of hydrogenation of CO 2 to CO is known as the Reverse Water Gas Shift (RWGS) reaction. The catalyst performance is critical because of the high stability and inertness of CO 2, the high reaction temperature, and the low conversion of CO 2, while by-products such as methane, methanol, etc. are produced.
The CO catalyst produced by reduction of CO 2 can be classified into alkali metal catalysts, supported metal oxides, mixed metal oxides, and transition metal carbide catalysts. The alkali metal catalyst shows excellent adsorption capacity for CO 2 and excellent reduction effect at lower temperature, but a large amount of water is generated during the reduction of CO 2, so that alkali metal is easily lost, and the catalyst is deactivated [ MORSE J R et al, energies, 2022, 15 (19): 12]. Cu-based and Fe-based are commonly used supported catalysts, and can be prepared by methods such as an impregnation method, an ion exchange method, an in-situ synthesis method and the like. However, due to its poor thermal stability, the active component of the catalyst tends to aggregate and grow at high temperatures, deactivating the catalyst [ CHEN C S ET AL, APPLIED CATALYSIS A:general, 2004, 257:97-106 ]. Noble metal supported catalysts, although remarkable, have limited their wide use in industry by their high cost and high cost [ Wang X et al ACS CATALYSIS, 2015, 5:6337-6349 ]. Mixed metal oxide catalysts can be prepared by co-precipitation or the like, but under high temperature conditions, the single metal oxide catalysts typically undergo reduction reactions to lose active sites, reducing the stability and activity of the catalyst, so that other atoms need to be introduced to form mixed metal oxides or additives need to be added to adjust the structure of the catalyst to improve the stability and activity of the catalyst, but this increases the complexity of preparation and gives poor yields [ WANG W ET AL, CATALYSIS TODAY, 2016, 259:402-408 ]. The transition metal carbide catalyst can be synthesized by a direct carbonization method, a chemical vapor deposition method, a ball milling method and the like. However, the transition metal carbide catalyst has problems of high synthesis cost, too low specific surface area, difficulty in molding, and the like, and is limited in its wide application [ MaY et al, journal of ENERGY CHEMISTRY, 2020, 50:37-43 ].
In summary, the existing catalyst for preparing carbon monoxide by carbon dioxide hydrogenation has the problems of high cost, complex synthesis method, poor conversion rate and selectivity caused by easy loss of active components or aggregation and inactivation of active components, and the like, and the problems greatly limit the development and application of the catalyst for preparing carbon monoxide by carbon dioxide hydrogenation.
Disclosure of Invention
Therefore, the invention aims to solve the technical problems of poor stability, complex preparation process and deactivation caused by extremely easy loss of alkali metal in the use process of the alkali metal-based catalyst in the prior art.
In order to solve the technical problems, the invention provides an alkali metal-based catalyst, and a preparation method and application thereof. The method has the advantages of simplicity, high efficiency, low cost and large-scale production; the prepared alkali metal-based catalyst can be used for high-efficiency and high-stability industrial production for catalyzing hydrogenation of carbon dioxide to generate carbon monoxide.
A first object of the present invention is to provide an alkali metal-based catalyst comprising transition metal oxide nanoparticles and a sod-type molecular sieve; alkali metal ions are encapsulated in the sod molecular sieve; the mass ratio of the transition metal oxide nano particles to the sod molecular sieve is 1:0.1-10.
In one embodiment of the present invention, the transition metal oxide nanoparticles have a particle size of 1nm to 500nm; the transition metal oxide is selected from one or more of copper oxide, manganese oxide, iron oxide, cobalt oxide, nickel oxide and zinc oxide.
In one embodiment of the present invention, the SOD-type molecular sieve is selected from one or more of an EMT-type molecular sieve, a FAR-type molecular sieve, a FAU-type molecular sieve, a FRA-type molecular sieve, a LIO-type molecular sieve, a LOS-type molecular sieve, a TOL-type molecular sieve, a GIU-type molecular sieve, an LTA-type molecular sieve, an LTN-type molecular sieve, a MAR-type molecular sieve, an SOD-type molecular sieve, and a TSC-type molecular sieve.
In one embodiment of the invention, the alkali metal ion is selected from one or more of sodium ion, potassium ion, rubidium ion, and cesium ion.
A second object of the present invention is to provide a process for preparing the alkali metal-based catalyst, comprising the steps of:
S1, dissolving a transition metal salt solution and a precipitant solution in water, adjusting the pH value of the solution to 6-8, and aging, washing, drying and roasting to obtain transition metal oxide nano particles;
dissolving an alkali metal source, a silicon source and an aluminum source in water, crystallizing, centrifuging, washing and drying to obtain a sod molecular sieve for encapsulating alkali metal ions;
S2, mixing the transition metal oxide nano particles in the step S1 with a sod molecular sieve for encapsulating alkali metal ions to obtain the alkali metal-based catalyst.
In one embodiment of the present invention, in S1, the concentration of the transition metal salt solution is 0.1mol/L to 5mol/L; the concentration of the precipitant solution is 0.1mol/L-5mol/L; the precipitant is one or more selected from sodium carbonate, sodium hydroxide, ammonia water and ammonium bicarbonate.
In one embodiment of the present invention, in S1, the alkali metal source is selected from one or more of alkali metal hydroxide, alkali metal oxide and alkali metal salt; the silicon source is selected from one or more of sodium silicate, silica gel, fumed silica, silica sol and tetraethoxysilane; the aluminum source is selected from one or more of sodium metaaluminate, aluminum hydroxide, aluminum isopropoxide and aluminum oxide.
In one embodiment of the invention, in S2, the means of mixing is selected from one or more of grinding, ball milling, shaking table, roller and co-spraying.
A third object of the present invention is to provide the use of said alkali metal based catalyst for catalyzing the hydrogenation of carbon dioxide to carbon monoxide.
In one embodiment of the invention, the temperature of the application is 300-700 ℃, the reaction pressure is 2-10 MPa, the gas flow rate is 10-200 mL/min, and the volume ratio of carbon dioxide to hydrogen is 1:1-10.
Compared with the prior art, the technical scheme of the invention has the following advantages:
According to the preparation method disclosed by the invention, alkali metal ions are encapsulated in the sod molecular sieve and then are directly and physically mixed with the transition metal oxide nano particles to prepare the alkali metal-based catalyst, so that the problem of alkali metal loss is effectively solved. The method has the advantages of simplicity, high efficiency, no complicated chemical process and the like, and can be used for the industrial production of high-efficiency and high-stability carbon dioxide hydrogenation reduction catalysts.
The alkali metal-based catalyst stabilizes alkali metal ions through the sod cage, and the alkali metal ions enhance the adsorption and activation of carbon dioxide; the transition metal oxide nano particles activate hydrogen, so that the alkali metal-based catalyst has high carbon dioxide conversion rate and carbon monoxide selectivity, and the service life of the alkali metal-based catalyst is also greatly prolonged.
Drawings
In order that the invention may be more readily understood, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings, in which:
FIG. 1 is a graph of time-to-conversion of carbon dioxide conversion over time at 300℃for an alkali metal-based catalyst of example 1 of the present invention;
FIG. 2 is a graph of carbon dioxide conversion versus time for the catalyst of comparative example 3 of the present invention;
FIG. 3 is a graph of carbon dioxide conversion versus time for the catalyst of comparative example 4 of the present invention;
FIG. 4 is an X-ray diffraction pattern of CuO nanoparticles, an SOD molecular sieve encapsulating alkali metal ions, and an alkali metal-based catalyst before participating in a catalytic reaction in test example 6 of the present invention;
FIG. 5 is an X-ray diffraction pattern of CuO nanoparticles, an SOD molecular sieve encapsulating alkali metal ions, and an alkali metal-based catalyst after participating in a catalytic reaction in test example 6 of the present invention;
FIG. 6 is a graph of hydrogen temperature programmed reduction (H 2 -TPR) of the CuO nanoparticles and alkali metal-based catalyst of test example 7 of the present invention;
FIG. 7 is a graph showing the adsorption isotherms of high temperature and high pressure carbon dioxide for the SOD molecular sieve of test example 8 of the present invention;
FIG. 8 is a schematic representation of the bonding of the structural motifs, sod cages, to alkali metal ions in a molecular sieve of the present invention.
Detailed Description
The present invention will be further described with reference to the accompanying drawings and specific examples, which are not intended to be limiting, so that those skilled in the art will better understand the invention and practice it.
In the present invention, the copper nitrate solutions used in examples and comparative examples were prepared by adding copper nitrate hexahydrate to deionized water at a concentration of 0.6mol/L, unless otherwise specified.
In the present invention, the sodium carbonate solutions used in examples and comparative examples were prepared by adding anhydrous sodium carbonate to deionized water at a concentration of 1mol/L, unless otherwise specified.
Example 1
The alkali metal-based catalyst of the present embodiment and the preparation method thereof specifically include the following steps:
S1, preparing transition metal oxide nano particles: heating 200mL of deionized water to 70 ℃ in a beaker, adding a copper nitrate solution and a sodium carbonate solution in parallel flow through a peristaltic pump, controlling the pH value of the solution in the beaker to be maintained at 7 in the whole process, continuously stirring and aging for 1h, filtering and washing, and then placing the solution in an oven for drying and roasting for 4h at 400 ℃ to obtain CuO nano particles with the particle size of about 200 nm;
s2, preparing an SOD molecular sieve for encapsulating alkali metal ions: adding ultrapure water, sodium metaaluminate, sodium hydroxide and sodium silicate into a clean container, preparing to obtain gel with the molar ratio of 7.5 (Na 2O)：1.0(A12O3)：2.0(SiO2)：165(H2 O), crystallizing at 100 ℃ for 12 hours, centrifuging, washing, and drying to obtain the SOD molecular sieve for encapsulating alkali metal ions;
s3, preparing an alkali metal-based catalyst: and (3) taking CuO nano particles and an SOD molecular sieve for encapsulating alkali metal ions in a mortar, wherein the mass ratio is 1:2, and grinding for 20min to obtain the alkali metal-based catalyst.
Example 2
The alkali metal-based catalyst of the present embodiment and the preparation method thereof specifically include the following steps:
s1, preparing transition metal oxide nano particles: as in example 1;
s2, preparing an SOD molecular sieve for encapsulating alkali metal ions: as in example 1;
S3, preparing an alkali metal-based catalyst: and (3) taking CuO nano particles and an SOD molecular sieve for encapsulating alkali metal ions in a mortar, wherein the mass ratio is 3:1, and grinding for 20min to obtain the alkali metal-based catalyst.
Example 3
The alkali metal-based catalyst of the present embodiment and the preparation method thereof specifically include the following steps:
s1, preparing transition metal oxide nano particles: as in example 1;
s2, preparing an SOD molecular sieve for encapsulating alkali metal ions: as in example 1;
s3, preparing an alkali metal-based catalyst: and (3) taking CuO nano particles and an SOD molecular sieve for encapsulating alkali metal ions in a mortar, wherein the mass ratio is 1:1, and grinding for 20min to obtain the alkali metal-based catalyst.
Example 4
The alkali metal-based catalyst of the present embodiment and the preparation method thereof specifically include the following steps:
s1, preparing transition metal oxide nano particles: as in example 1;
S2, preparing FAU molecular sieves for encapsulating alkali metal ions: adding ultrapure water, sodium metaaluminate, sodium hydroxide, potassium hydroxide and sodium silicate into a clean container, preparing to obtain gel with a molar ratio of 5.5 (Na 2O)：1.65(K2O)：1.0(A12O3)：2.0(SiO2)：165(H2 O), aging at 70 ℃ for 3 hours, crystallizing at 93 ℃ for 12 hours, centrifuging, washing and drying to obtain FAU molecular sieve for encapsulating alkali metal ions;
s3, preparing an alkali metal-based catalyst: as in example 1.
Example 5
The alkali metal-based catalyst of the present embodiment and the preparation method thereof specifically include the following steps:
s1, preparing transition metal oxide nano particles: as in example 1;
S2, preparing an LTA molecular sieve for encapsulating alkali metal ions: taking a clean container, adding ultrapure water, sodium metaaluminate, sodium hydroxide and sodium silicate, preparing to obtain gel with a molar ratio of 3.165 (Na 2O)：1.0(A12O3)：2.0(SiO2)：160(H2 O), crystallizing at 100 ℃ for 4 hours, centrifuging, washing and drying to obtain the LTA molecular sieve for encapsulating alkali metal ions;
s3, preparing an alkali metal-based catalyst: as in example 1.
Example 6
The alkali metal-based catalyst of the present embodiment and the preparation method thereof specifically include the following steps:
s1, preparation of CuO nano particles: as in example 1;
S2, preparing an EMT molecular sieve for encapsulating alkali metal ions: taking a clean container, adding ultrapure water, sodium metaaluminate, sodium hydroxide and sodium silicate, preparing to obtain gel with a molar ratio of 18.5 (Na 2O)：1.0(A12O3)：5.0(SiO2)：0.5(TEAOH)：240(H2 O), crystallizing at 30 ℃ for 72 hours, centrifuging, washing and drying to obtain the EMT molecular sieve for encapsulating alkali metal ions;
s3, preparing an alkali metal-based catalyst: as in example 1.
Example 7
The alkali metal-based catalyst of the present embodiment and the preparation method thereof specifically include the following steps:
s1, preparation of CuO nano particles: as in example 1;
S2, preparing FRA molecular sieves for encapsulating alkali metal ions: taking a clean container, adding ultrapure water, sodium metaaluminate, sodium hydroxide and sodium silicate, preparing to obtain gel with a molar ratio of 3.75 (Na 2O)：0.75(A12O3)：1.0(SiO2)：670(H2 O), crystallizing at 110 ℃ for 12 hours, centrifuging, washing and drying to obtain the FRA molecular sieve for encapsulating alkali metal ions;
s3, preparing an alkali metal-based catalyst: as in example 1.
Example 8
The alkali metal-based catalyst of the present embodiment and the preparation method thereof specifically include the following steps:
s1, preparation of CuO nano particles: as in example 1;
S2, preparing an LTN molecular sieve for encapsulating alkali metal ions: taking a clean container, adding ultrapure water, sodium metaaluminate, sodium hydroxide and sodium silicate, preparing to obtain gel with a molar ratio of 21 (Na 2O)：1(A12O3)：1.8(SiO2)：670(H2 O), crystallizing at 100 ℃ for 1h, centrifuging, washing and drying to obtain the LTN molecular sieve for encapsulating alkali metal ions;
s3, preparing an alkali metal-based catalyst: as in example 1.
Example 9
The alkali metal-based catalyst of the present embodiment and the preparation method thereof specifically include the following steps:
S1, preparing transition metal oxide nano particles: basically, the same as in example 1, except that the copper nitrate solution was changed to a nitrate solution in which the molar ratio of copper nitrate, zinc nitrate and aluminum nitrate was 68:29:3, to obtain CuZnAl mixed metal oxide nanoparticles;
s2, preparing an SOD molecular sieve for encapsulating alkali metal ions: as in example 1;
s3, preparing an alkali metal-based catalyst: as in example 1.
Comparative example 1
CuO nanoparticles prepared in example 1.
Comparative example 2
The CuZnAl mixed metal oxide nanoparticles prepared in example 9.
Comparative example 3
Cu (NO 3)2 is dissolved in a mixture of water and acetone, mixed with purchased SBA-15, heat-preserved for 1h at 60 ℃, and then heat-treated for 2h in vacuum at 350 ℃ at a heating rate of 1 ℃/min to obtain Cu/SBA-15.
Comparative example 4
S1, dissolving Cu (NO 3)2 and Ce (NO 3)3 in an atomic ratio of 3:7 in deionized water, and placing the obtained solution in a room temperature vacuum oven to obtain gel-like light blue salt;
S2, salt (1 g) was mixed with 1.5g SBA-15 and the solid mixture was ground in a mortar. The mortar was placed on a hot plate at 70 ℃ until the bluish salt dissolved in SBA-15, and the mixture was then placed in a room temperature vacuum oven overnight. Heating the dried mixture from room temperature to 700 ℃ in a muffle furnace at a heating speed of 1 ℃/min, preserving heat for 12h, and then cooling to room temperature; SBA-15 was removed by washing 3 times with 2mol/L sodium hydroxide solution at 70℃and the porous metal oxide product was recovered by centrifugation and washed 3 times with deionized water. Residual sodium was removed with aqueous ammonia (1 mol/L), dried at 100℃and calcined at 400℃for 1 hour to give Cu/CeO 2.
Test example 1
The alkali metal-based catalyst of example 1 was subjected to tabletting, crushing, grinding and sieving for 20-40 mesh for evaluating the reaction, and carbon dioxide conversion and carbon monoxide selectivity of the alkali metal-based catalyst under different catalytic conditions (different reaction temperatures, different reaction pressures, different gas flow rates), the carbon monoxide selectivity being the selectivity of carbon monoxide in all products including methanol, methane, etc. were investigated.
(1) Different reaction temperatures
The alkali metal-based catalyst of example 1 is applied to the hydrogenation of carbon dioxide to prepare carbon monoxide, and the reaction conditions are as follows: the reduction temperature is 300 ℃, the reduction time is 2 hours, the reaction temperature is 200 ℃, 300 ℃,350 ℃, 400 ℃, 500 ℃, 600 ℃, 700 ℃ and 800 ℃, the reaction pressure is 2.5Mpa, the volume ratio of carbon dioxide to hydrogen is 1:3, the gas flow rate is 40mL/min per gram of catalyst, and the carbon dioxide conversion rate and the carbon monoxide selectivity are measured as shown in table 1:
TABLE 1
As can be seen from Table 1, as the reaction temperature increases, the carbon dioxide conversion rate gradually increases, and the carbon dioxide conversion rate reaches 19.3% at 300℃and 34.9% at 400 ℃. This is because the higher the temperature, the higher the rate of Cu particles activating hydrogen, and the higher the carbon dioxide conversion. At temperatures above 300 ℃, the carbon dioxide conversion approaches the thermodynamic equilibrium conversion. The Cu particles are not deactivated by sintering at high temperature and the catalyst remains catalytically active. The carbon monoxide selectivity decreases with increasing temperature, particularly after 400 ℃, because the rate of Cu activation of hydrogen gradually exceeds the rate of molecular sieve activation of carbon dioxide. The selectivity of carbon monoxide can be improved without substantially reducing the carbon dioxide conversion by adjusting the ratio of Cu to molecular sieve and the space velocity.
(2) Different reaction pressures
The alkali metal-based catalyst of example 1 is applied to the hydrogenation of carbon dioxide to prepare carbon monoxide, and the reaction conditions are as follows: the reduction temperature is 300 ℃, the reduction time is 2 hours, the reaction temperature is 300 ℃, the reaction pressure is 0.1Mpa, 0.5Mpa, 1.5Mpa, 2.5Mpa and 3.5Mpa respectively, the volume ratio of carbon dioxide to hydrogen is 1:3, the gas flow rate is 40mL/min per gram of catalyst, and the carbon dioxide conversion rate and the carbon monoxide selectivity are measured as shown in Table 2:
TABLE 2
As can be seen from Table 2, as the reaction pressure increased, the carbon dioxide conversion was gradually increased, and at 3.5MPa, the carbon dioxide conversion was 31.1%. The pressure is increased, the carbon dioxide adsorption amount of the molecular sieve is increased, and the carbon dioxide conversion rate of the catalyst is increased. For the reaction of preparing carbon monoxide by hydrogenation of carbon dioxide, the pressure increase is beneficial to the progress of side reactions. However, unlike the traditional catalyst for preparing carbon monoxide by hydrogenating carbon dioxide, the selectivity of carbon monoxide of the catalyst is improved from 0.1Mpa to 3.5Mpa and only slightly reduced. In practical industrial production applications, the increase in reaction pressure also reduces the volume of the gas reaction apparatus and reduces the equipment cost. In addition, carbon dioxide conversion at 3.5Mpa exceeds equilibrium conversion at 300 ℃ (23%), also indicating that the catalyst bypasses the thermodynamic limitations of single site catalysis of conventional catalysts.
(3) Different gas flow rates
The alkali metal-based catalyst of example 1 is applied to the hydrogenation of carbon dioxide to prepare carbon monoxide, and the reaction conditions are as follows: the reduction temperature is 300 ℃, the reduction time is 2 hours, the reaction pressure is 2.5Mpa, the volume ratio of carbon dioxide to hydrogen is 1:3, the gas flow rates are respectively 10mL/min, 20mL/min, 40mL/min, 120mL/min and 200mL/min for each gram of catalyst, the carbon dioxide conversion rate and the carbon monoxide selectivity are measured at the reaction temperature of 300 ℃, the carbon dioxide conversion rate and the carbon monoxide selectivity are shown in Table 3, and the carbon dioxide conversion rate and the carbon monoxide selectivity are measured at the reaction temperature of 500 ℃ are shown in Table 4:
TABLE 3 Table 3
TABLE 4 Table 4
As can be seen from tables 3 and 4, the carbon dioxide conversion was gradually decreased with increasing gas flow rate, and the carbon dioxide conversion was 28.9% at 300℃and 51.2% at 500℃at a gas flow rate of 10mL/min per gram of catalyst. However, as the gas flow rate increases, the carbon monoxide selectivity gradually decreases at a reaction temperature of 300℃and gradually increases at a reaction temperature of 500 ℃. At 300 ℃, the by-product is mainly methanol. At 500 ℃, the byproduct is mainly methane. This is because the gas flow rate affects the progress of the catalytic reaction by kinetic factors. In terms of carbon dioxide conversion, the faster the gas flow rate, the shorter the contact time of the reactant with the catalyst, and the lower the carbon dioxide conversion. In terms of product selectivity, the faster the gas flow rate, the faster the catalyst surface species renewal, and the lower the degree of product hydrogenation. At 300 ℃, the carbon species first forms formate and other intermediates on the catalyst surface, and methanol is formed by direct desorption. The lower the space velocity, the longer the intermediate residence time, the easier it is to convert from an intermediate species to carbon monoxide, and the higher the carbon monoxide selectivity. At 500 ℃, the Cu activation hydrogen rate exceeds the molecular sieve activation carbon dioxide rate, and the carbon species may be over hydrogenated to methane. The higher the space velocity, the shorter the intermediate residence time, the less over-hydrogenation and the higher the carbon monoxide selectivity.
Test example 2
Examples 1-3 alkali metal based catalysts were used in the hydrogenation of carbon dioxide to carbon monoxide under the following reaction conditions: the reduction temperature is 300 ℃, the reduction time is 2 hours, the reaction temperature is 300 ℃, the reaction pressure is 2.5Mpa, the volume ratio of carbon dioxide to hydrogen is 1:3, the gas flow rate is 40mL/min per gram of catalyst, and the carbon dioxide conversion rate and the carbon monoxide selectivity are measured as shown in Table 5:
TABLE 5
As can be seen from Table 5, the mass ratio of CuO to SOD molecular sieve is changed from 3:1 to 1:2 at 300 ℃, and the conversion rate of carbon dioxide is improved from 12.1% to 19.3%. The change of the mass ratio of CuO to the molecular sieve drives the change of the hydrogen activation rate and the carbon dioxide activation rate in the catalyst per unit mass. The catalyst carbon dioxide conversion is optimized when the Cu hydrogen activation rate and the molecular sieve carbon dioxide activation rate are matched to each other.
Test example 3
The catalysts of examples 1, 4-8 and comparative example 1 were used for the hydrogenation of carbon dioxide to carbon monoxide under the following reaction conditions: the reduction temperature is 300 ℃, the reduction time is 2 hours, the reaction temperature is 300 ℃, the reaction pressure is 2.5Mpa, the volume ratio of carbon dioxide to hydrogen is 1:3, the gas flow rate is 40mL/min per gram of catalyst, and the carbon dioxide conversion rate and the carbon monoxide selectivity are measured as shown in Table 6:
TABLE 6
As can be seen from table 6, the pure CuO nanoparticles in comparative example 1 are almost non-reactive to the reaction, while the conversion of carbon dioxide of the alkali metal based catalysts in examples 1 and 4-8 is greatly improved, which indicates that various alkali metal-encapsulated molecular sieves containing a sod cage can cooperate with CuO to catalyze the hydrogenation of carbon dioxide to produce carbon monoxide, and also demonstrates the versatility of the sod molecular sieves. The metal particles have an activating effect on hydrogen, while the molecular sieve can adsorb activated carbon dioxide. Hydrogen overflows after being activated on Cu, and migrates to the molecular sieve to react with the carbon dioxide adsorbed and activated by the molecular sieve, so as to complete the hydrogenation of the carbon dioxide. The two components cooperate to catalyze the hydrogenation of carbon dioxide to synthesize carbon monoxide.
Test example 4
The catalysts of example 9 and comparative example 2 were respectively applied to the hydrogenation of carbon dioxide to produce carbon monoxide under the following reaction conditions: the reduction temperature is 300 ℃, the reduction time is2 hours, the reaction temperature is 300 ℃, the reaction pressure is 2.5Mpa respectively, the volume ratio of carbon dioxide to hydrogen is 1:3, the gas flow rate is 40mL/min per gram of catalyst, and the carbon dioxide conversion rate and the carbon monoxide selectivity are measured as shown in Table 7:
TABLE 7
As can be seen from table 7, the alkali metal-based catalyst of example 9 increased the carbon dioxide conversion by about 12% with substantially unchanged carbon monoxide selectivity relative to comparative example 2. On the basis of the catalytic activity of the metal particles, the catalyst is physically mixed with a molecular sieve for encapsulating alkali metal, so that the conversion rate of carbon dioxide is further improved, and the method is proved to have universality on transition composite metal oxides.
Test example 5
The catalysts of example 1 and comparative examples 4-5 were applied to the hydrogenation of carbon dioxide to carbon monoxide, respectively, under the following reaction conditions: the reduction temperature is 300 ℃, the reduction time is 2 hours, the reaction temperature is 300 ℃, the reaction pressure is 2.5Mpa, the volume ratio of carbon dioxide to hydrogen is 1:3, the gas flow rate is 40mL/min per gram of catalyst, the carbon dioxide conversion rate and the carbon monoxide selectivity are shown in table 8, and the time-conversion rate diagram of the change of the carbon dioxide conversion rate with time at the reaction temperature of 300 ℃ is shown in fig. 1,2 and 3:
TABLE 8
As can be seen from table 8 and fig. 1,2, 3, example 1 exhibited the best catalytic performance compared to comparative examples 4-5. Comparative example 4: under the given conditions (only 300 ℃), the catalytic performance of the catalyst can only be maintained for 120min. The comparative time-conversion plot shows that after about 120 minutes the catalyst performance of comparative example 4 began to decline and after about 8 hours the catalyst performance of comparative example 5 began to decline, whereas the catalyst of example 1 had a carbon dioxide conversion reduction of less than 10% of the initial conversion in a 200 hour catalytic evaluation. Further shows that the catalyst has extremely high thermal stability and can be used as an efficient and stable carbon dioxide hydrogenation reduction catalyst.
Test example 6
Based on example 1 and the test example, X-ray diffraction was performed on CuO nanoparticles (abbreviated as CuO), SOD molecular sieves (abbreviated as SOD) encapsulating alkali metal ions, and alkali metal-based catalysts (abbreviated as CuO-SOD) before and after participation in the catalytic reaction, and the results are shown in fig. 4 and 5. As can be seen from fig. 4 and 5, the characteristic spectra of XRD of copper oxide are matched before the reaction of CuO and Cu in CuO-SOD, and after the reaction, cuO maintains the state of zero-valent copper. The crystal structure of the SOD molecular sieve is kept stable before and after the reaction. Zero-valent copper has activating capability to hydrogen and does not have activating capability to carbon dioxide, so that the situation that the active sites are too close when monovalent copper and zero-valent copper are simultaneously used as active sites is avoided, and side reactions are reduced. The stable crystal structure of the molecular sieve shows that the framework collapse caused by the loss of alkali metal ions does not occur, and the performance of the catalyst is kept stable.
Test example 7
Based on example 1, hydrogen temperature programmed reduction (H 2 -TPR) tests were performed on CuO nanoparticles (abbreviated as CuO) and alkali metal based catalysts (abbreviated as CuO-SOD) on Micromeritics AutoChem II chemisorption analyzer. In a typical experiment, about 0.1g of the sample was pre-treated in an Ar atmosphere at 773K for 1h and then cooled to 323K in flowing Ar. The H 2 -TPR curve was recorded from 323K-773K in flowing 10% H 2/Ar at a heating rate of 10K/min. The results are shown in FIG. 6. As can be seen from fig. 6, after the CuO nanoparticles are physically mixed with the SOD molecular sieve encapsulating the alkali metal ions, the reduction peak of CuO is shifted to low temperature, which indicates that the two components are synergistically combined after physical mixing, the reduction temperature of CuO is reduced, i.e., the capability of Cu to activate hydrogen is improved.
Test example 8
Based on example 1, the amount of CO 2 adsorbed by a sample at 300℃under a pressure ranging from 0 to 50bar was measured on a high-temperature high-pressure gas adsorber of the national standard quantum H-Sorb 2600 using an SOD molecular sieve, and the result is shown in FIG. 7. It can be seen from FIG. 7 that the carbon dioxide adsorption amount of the SOD molecular sieve increases with the pressure rise in the pressure range of 0 to 50 bar. The results indicate that carbon dioxide is not only adsorbed on the surface of the molecular sieve, but also can be adsorbed in the sod cage under a certain pressure. This is also responsible for the increased pressure and increased carbon dioxide conversion of the catalyst, corresponding to the test results described above.
Test example 9
Based on test example 3, elemental analysis was performed on the catalyst before and after the reaction on an inductively coupled plasma atomic emission spectrometer (ICP-AES, bruk 5110). In a typical test, about 10mg of catalyst was weighed, 1mL aqua regia and 0.5mL hydrofluoric acid were added, heated to complete dissolution, cooled, and the liquid diluted with 1wt% HNO 3 solution and sized for elemental content testing. The test results are shown in table 9:
TABLE 9
As can be seen from table 9, the alkali metal-based catalyst was prepared by physically mixing CuO with different alkali metal-encapsulated molecular sieves, and the mass fraction of alkali metal in the catalyst was not changed before and after the reaction, i.e., alkali metal ions were not lost. The results demonstrate that the sod-type molecular sieve encapsulating alkali metal (fig. 8) is capable of effectively stabilizing alkali metal, maintaining long-term stability of catalyst catalytic performance.
It is apparent that the above examples are given by way of illustration only and are not limiting of the embodiments. Other variations and modifications of the present invention will be apparent to those of ordinary skill in the art in light of the foregoing description. It is not necessary here nor is it exhaustive of all embodiments. And obvious variations or modifications thereof are contemplated as falling within the scope of the present invention.
Claims (6)
1. A process for the preparation of an alkali metal-based catalyst, comprising the steps of:
S1, dissolving a transition metal salt solution and a precipitant solution in water, adjusting the pH value of the solution to 6-8, and aging, washing, drying and roasting to obtain transition metal oxide nano particles;
dissolving an alkali metal source, a silicon source and an aluminum source in water, crystallizing, centrifuging, washing and drying to obtain a sod molecular sieve for encapsulating alkali metal ions;
S2, mixing the transition metal oxide nano particles in the step S1 with a sod molecular sieve for encapsulating alkali metal ions to obtain the alkali metal-based catalyst; the mixing mode is selected from one or more of grinding, ball milling, shaking table, roller and co-spraying;
The alkali metal-based catalyst comprises transition metal oxide nano particles and a sod molecular sieve; alkali metal ions are encapsulated in the sod molecular sieve; the alkali metal ions are selected from one or more of sodium ions, potassium ions, rubidium ions and cesium ions; the SOD molecular sieve is selected from one or more of an EMT type molecular sieve, a FAR type molecular sieve, a FAU type molecular sieve, a FRA type molecular sieve, a LIO type molecular sieve, an LOS type molecular sieve, a TOL type molecular sieve, a GIU type molecular sieve, an LTA type molecular sieve, an LTN type molecular sieve, a MAR type molecular sieve, an SOD type molecular sieve and a TSC type molecular sieve; the mass ratio of the transition metal oxide nano particles to the sod molecular sieve is 1:0.1-10.
2. The method for preparing an alkali metal-based catalyst according to claim 1, wherein the particle size of the transition metal oxide nanoparticles is 1nm to 500nm; the transition metal oxide is selected from one or more of copper oxide, manganese oxide, iron oxide, cobalt oxide, nickel oxide and zinc oxide.
3. The method for producing an alkali metal-based catalyst according to claim 1, wherein in S1, the concentration of the transition metal salt solution is 0.1mol/L to 5mol/L; the concentration of the precipitant solution is 0.1mol/L-5mol/L; the precipitant is one or more selected from sodium carbonate, sodium hydroxide, ammonia water and ammonium bicarbonate.
4. The method for producing an alkali metal-based catalyst according to claim 1, wherein in S1, the alkali metal source is selected from one or more of alkali metal hydroxide, alkali metal oxide and alkali metal salt; the silicon source is selected from one or more of sodium silicate, silica gel, fumed silica, silica sol and tetraethoxysilane; the aluminum source is selected from one or more of sodium metaaluminate, aluminum hydroxide, aluminum isopropoxide and aluminum oxide.
5. Use of an alkali metal-based catalyst prepared by the process of any one of claims 1-4 for catalyzing the hydrogenation of carbon dioxide to carbon monoxide.
6. The use according to claim 5, wherein the temperature of the use is 300-700 ℃, the reaction pressure is 2-10 MPa, the gas flow rate is 10-200 mL/min, and the volume ratio of carbon dioxide to hydrogen is 1:1-10.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410476263.3A CN118059924B (en) | 2024-04-19 | 2024-04-19 | Alkali metal-based catalyst and preparation method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410476263.3A CN118059924B (en) | 2024-04-19 | 2024-04-19 | Alkali metal-based catalyst and preparation method and application thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN118059924A CN118059924A (en) | 2024-05-24 |
| CN118059924B true CN118059924B (en) | 2024-07-09 |
Family
ID=91105993
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410476263.3A Active CN118059924B (en) | 2024-04-19 | 2024-04-19 | Alkali metal-based catalyst and preparation method and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN118059924B (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106268923A (en) * | 2016-07-15 | 2017-01-04 | 中国科学院大连化学物理研究所 | A kind of preparation method and application of bifunctional catalyst |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114950534B (en) * | 2022-06-01 | 2023-09-26 | 南京工业大学 | Process for preparing aromatic hydrocarbon by catalyzing carbon dioxide hydrogenation by double-function catalyst |
-
2024
- 2024-04-19 CN CN202410476263.3A patent/CN118059924B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106268923A (en) * | 2016-07-15 | 2017-01-04 | 中国科学院大连化学物理研究所 | A kind of preparation method and application of bifunctional catalyst |
Non-Patent Citations (2)
| Title |
|---|
| Modeling of reverse water–gas shift reaction in a membrane integrated microreactor;Mert Can Ince，等;《Catalysis Today》;20230321;第第418卷卷;第1-9页 * |
| Synthesis of mesoporous sodalite from coal-fred slag for CO2 capture;Yukun Yin，等;《Journal of the Indian Chemical Society》;20240117;第第101卷卷;第1-7页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN118059924A (en) | 2024-05-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110252378B (en) | Monoatomic double-active-center Co-based ammonia synthesis catalyst and preparation method thereof | |
| CN107497439B (en) | Copper-based catalyst for reverse water gas shift reaction and preparation method thereof | |
| CN111841608A (en) | High-activity and anti-carbon composite catalyst, preparation method thereof and application thereof in methane dry gas reforming | |
| CN107029769A (en) | A kind of preparation and its application of carried copper oxide catalyst | |
| CN103374430A (en) | High-stability oxygen carrier, preparation method and applications | |
| CN118059924B (en) | Alkali metal-based catalyst and preparation method and application thereof | |
| CN109261222A (en) | A kind of preparation method of the high stability bimetallic hollow core core/shell-type catalyst for the reaction of toluene steam reforming | |
| JPWO2014057839A1 (en) | Method for producing composite oxide and composite oxide catalyst | |
| CN110893346A (en) | Bimetallic low-temperature methanation catalyst and preparation method and application thereof | |
| CN102500386A (en) | Preparation method for cerium nickel composite oxide catalytic material | |
| CN112473678A (en) | Catalyst for wet-process coke quenching steam mixed reforming of methane and preparation method thereof | |
| CN109261183B (en) | Cobalt-based catalyst for methanation of carbon dioxide and application thereof | |
| KR20230034166A (en) | METHOD FOR SYNTHESIS Ni/AlMaOx CATALYSTS FOR AMMONIA DECOMPOSITION USING CATION ANION DOUBLE HYDROLYSIS | |
| CN115155585A (en) | Carbon dioxide capture and catalytic hydrogenation olefin preparation dual-function composite material, preparation method and application | |
| CN103386307B (en) | Preparation method for Ni-Mg/Al2O3 catalyst | |
| CN112058277B (en) | High-activity catalyst for ammonia synthesis and preparation method thereof | |
| CN108043412A (en) | A kind of preparation method for synthesizing methanol by hydrogenating carbon dioxide catalyst | |
| CN114100625B (en) | Cobalt-molybdenum-based perovskite sulfur-tolerant shift reaction catalyst and preparation method thereof | |
| CN114602544A (en) | Modified Cu-CHA molecular sieve composite catalyst and preparation method and application thereof | |
| CN113522354A (en) | Preparation and application of molecular sieve supported composite metal oxide catalyst | |
| CN113292519A (en) | Magnetic gold-cobalt composite catalyst and preparation method and application thereof | |
| CN113731422A (en) | Preparation method of slurry bed methane synthesis catalyst | |
| CN112023976A (en) | Bimetallic modified MCM-41 molecular sieve catalyst, preparation method and application | |
| CN103611565B (en) | A kind of Catalysts and its preparation method of hydrogenation of dimethyl oxalate to synthesizing ethylene glycol and application | |
| CN116196936B (en) | Spherical micro-mesoporous composite material catalyst for preparing hydrogen by reforming methanol steam and preparation method and application thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant |