CN-121972178-A - Nb-based composite oxide supported metal catalyst, preparation method and application thereof in hydrodeoxygenation aviation oil production

Abstract

The application belongs to the field of catalysis, and provides a Nb-based composite oxide supported metal catalyst, a preparation method and application thereof in hydrodeoxygenation aviation oil production. The catalyst comprises a gamma-Al 2 O 3 and Nb 2 O 5 (or NbOPO 4 ) dual carrier and one or more hydrogenation active metals. The hydrodeoxygenation catalyst provided by the application has good acidity and hydrogenation performance under the interaction of two carriers, and the acidity and hydrogenation performance are proved to be superior to those of the original single-carrier catalyst through characterization, and the performance of the hydrodeoxygenation catalyst in hydrodeoxygenation aviation oil of biomass derivative aldol condensation products (long-chain oxygen-containing compounds) is far superior to that of the single-carrier catalyst with the same metal loading.

Inventors

• CHEN LUNGANG
• ZHU NING
• HUANG HAIYUN
• ZHANG XINGHUA
• MA LONGLONG

Assignees

• 东南大学

Dates

Publication Date

20260505

Application Date

20260226

Claims (10)

1. 1. A Nb-based composite oxide supported metal catalyst, characterized in that the catalyst is denoted xM/NyAz and comprises one or more hydrogenation-active metals, wherein M and x are metal and metal loadings, respectively, N and a are Nb-containing support and γ -Al 2 O 3 support, respectively, and the ratio of y and z is the mass ratio between the two supports.
2. 2. The Nb-based composite oxide supported metal catalyst according to claim 1, wherein the hydrogenation active metal is one or more of Pt, pd, rh, ru, ni, co, cu, and the Nb-containing support comprises Nb 2 O 5 and NbOPO 4 .
3. 3. The Nb-based composite oxide supported metal catalyst according to claim 1, wherein the hydrogenation active metal component in the catalyst accounts for 0.2 to 20wt% of the catalyst based on the total mass of the catalyst, and the mass ratio of the two carriers in the catalyst is 0 to 4:1.
4. 4. The method for producing a Nb-based composite oxide supported metal catalyst according to claim 1, characterized by comprising: Mixing the Nb carrier, the gamma-Al 2 O 3 carrier, the metal salt solution and the dispersing agent, stirring at normal temperature, heating to evaporate water, drying, roasting in air atmosphere, and then placing in hydrogen-inert gas mixture for reduction to obtain the Nb-based composite oxide supported metal catalyst.
5. 5. The method for preparing a Nb-based composite oxide supported metal catalyst according to claim 4, wherein the dispersant is ethanol or ethylene glycol, and the ratio of the dispersant to the carrier is 1 to 4 ml/8 g.
6. 6. The preparation method of the Nb-based composite oxide supported metal catalyst according to claim 4, wherein the stirring time at normal temperature is 6-24 hours, the drying condition is that the drying is carried out for 12-36 hours at 90-100 ℃, the roasting condition in the air atmosphere is that the temperature is firstly increased to 240-260 ℃, the temperature is kept for 1-3 hours, then the temperature is increased to 350-750 ℃, the roasting is carried out for 4-6 hours, the heating rate is 1-3 ℃ per minute, the reduction condition is that the temperature is firstly increased to 240-260 ℃ in the 8-12 vol% H 2 /Ar atmosphere, the temperature is kept for 1-3 hours, the temperature is increased to 400-600 ℃ and the reduction is carried out for 2-6 hours, and the heating rate is 1-3 ℃ per minute.
7. 7. The method for producing a Nb-based composite oxide supported metal catalyst according to claim 4, wherein the metal salt is one or more of palladium nitrate, palladium sulfate, palladium chloride, palladium acetate, and nickel nitrate.
8. 8. Use of the catalyst of any one of claims 1 to 3 in hydrodeoxygenation of aviation oil, wherein the method comprises: And in the presence of the catalyst and an organic solvent, the condensation product of furfural and ketone is subjected to hydrodeoxygenation reaction to generate C8-C16 alkane.
9. 9. The use according to claim 8, wherein the hydrodeoxygenation aviation oil is prepared by stirring the composition for 2-10 hours at a temperature of 200-280 ℃ and a hydrogen pressure of 1-5 MPa, the organic solvent is cyclohexane, and the ketone is one or more of acetone, 2-butanone, 3-pentanone, 2-hexanone, 2, 5-hexanedione, methyl isobutyl ketone, cyclopentanone, cyclohexanone and levulinic acid.
10. 10. The use according to claim 8, wherein the ratio of reaction substrate, catalyst and organic solvent is 0.1 g:0.01 to 0.04 g 5: 5 mL.

Description

Nb-based composite oxide supported metal catalyst, preparation method and application thereof in hydrodeoxygenation aviation oil production Technical Field The invention belongs to the field of catalysis, and particularly relates to a Nb-based composite oxide supported metal catalyst, a preparation method and application thereof in hydrodeoxygenation aviation oil production. Background In view of the irreversible consumption of renewable resources worldwide, the increasing demand for fuels, and the potential concerns over the greenhouse effect, it is imperative to develop new, sustainable and environmentally friendly energy sources to synthesize liquid fuels. In this context, biomass is considered to be the most promising resource for the production of hydrocarbonaceous liquid fuels. In order to achieve the aim, biomass is converted into fuel or chemicals with high added value, a lignocellulose hydrolysate furfural is selected as a raw material, aldol condensation reaction is carried out on the raw material and other small molecular ketones which can be obtained through biomass conversion to prolong carbon chains, long-chain oxygen-containing compounds with carbon chain numbers which meet the fuel standard are obtained, and then, long-chain alkane is obtained through hydrodeoxygenation reaction. The process can achieve the aim of obtaining alkanes with different properties by adjusting ketones to adjust fuel properties. However, the molecular structure of the obtained condensation product is complex, the hydrodeoxygenation reaction process involves a plurality of reaction links, and the reaction conditions and the catalyst need to be optimized to realize efficient conversion and utilization. The hydrodeoxygenation catalyst needs to possess both hydrogenation sites, which are typically metal sites, and deoxygenation sites, which are acidic sites, which are functional. The currently developed Hydrodeoxygenation (HDO) catalysts generally face a plurality of challenges, such as high catalyst cost, severe reaction conditions caused by insufficient catalytic activity, and the fact that the carbon chain length of the obtained alkane product does not meet aviation fuel standards, which severely limit the practical application of the alkane product in industry. Most of the hydrodeoxygenation catalysts used in research remain noble metal catalysts, and are superior in performance but expensive in cost. It is therefore desirable to provide a catalyst that is less costly and has greater hydrodeoxygenation properties. Disclosure of Invention The invention aims to provide a preparation method of a Nb-based composite oxide supported metal catalyst and application of the Nb-based composite oxide supported metal catalyst in preparing aviation oil by hydrodeoxygenation, and the catalyst prepared by the method has more excellent activity and stability. In order to achieve the above purpose, the technical scheme provided by the invention is as follows: A Nb-based composite oxide supported metal catalyst, the catalyst being denoted xM/NyAz, the catalyst comprising one or more hydrogenation-active metals, the catalyst support comprising a mixture of Nb, al, O and P elements, wherein M and x are metal and metal loadings, respectively, N and a are Nb-containing support and γ -Al 2O3 support, respectively, and the ratio of y and z is the mass ratio between the two supports. Further, the hydrogenation active metal is one or more of Pt, pd, rh, ru, ni, co, cu. Further, the hydrogenation active metal component in the catalyst accounts for 0.2-20wt% of the mass of the catalyst. Further, the Nb-containing carrier includes Nb 2O5 and NbOPO 4 having properties similar thereto. Further, based on the total mass of the catalyst, the mass ratio of the two carriers in the catalyst is 0-4:1. According to another aspect of the present invention, there is provided a method for preparing a hydrodeoxygenation catalyst, comprising: Mixing the Nb carrier, the gamma-Al 2O3 carrier, the metal salt solution and the dispersing agent in a beaker, stirring at normal temperature, heating to evaporate water, drying, roasting in air atmosphere, and then placing in a hydrogen-inert gas mixed gas for reduction to obtain the Nb-based composite oxide supported metal catalyst. Further, the dispersing agent is ethanol or glycol, and the mass ratio of the dispersing agent to the carrier is (1-4) mL/8 g. Further, the stirring time at normal temperature is 6-24 hours. Further, the drying condition is that the drying is carried out for 12-36 hours at the temperature of 90-100 ℃. Further, the roasting condition in the air atmosphere is that the temperature is firstly increased to 240-260 ℃, the heat is preserved for 1-3 hours, then the temperature is increased to 350-750 ℃, the roasting is carried out for 4-6 hours, and the temperature increasing rate is 2 ℃ per minute. Further, the reduction condition is that under the atmosphere of 8-12 vol% H 2/Ar (8-12 vol% is the v