Preparation, performance test method and application of zirconium-containing supported nano-ruthenium catalyst

Abstract

The invention discloses a preparation method, a performance test method and an application of a zirconium-supported nano-ruthenium catalyst. The preparation method comprises the following steps: S1, dissolving Al(NO3)3.9H2O or Co(NO3)2.6H2O and ZrOCl2.8H2O in water; S2, adding triethylamine, and carrying out temperature control treatment and aging on the obtained solution; S3, carrying out suctionfiltration on the aged solution to obtain a filter cake; S4, grinding the filter cake obtained in step S3 to form a powder, calcining the powder, and cooling the calcined powder to room temperature in order to prepare a ZrxAlO carrier or a CoZrxO carrier; S5, dropwise adding a polyvinylpyrrolidone solution to an aqueous solution of ruthenium hydrochloride in the dark; S6, adding the ZrxAlO carrier or the CoZrxO carrier to a mixed solution obtained in step S5, dropwise adding a sodium borohydride solution, carrying out suction filtration on the obtained solution, and performing washing; and S7, placing a filter cake powder obtained in step S6 in a tubular furnace, introducing hydrogen, cooling the tubular furnace to room temperature, and taking out the solid powder to obtain the Ru / ZrxAlOcatalyst or the Ru / CoZrxO catalyst. Two zirconium-supported nano-ruthenium catalysts with stable performances, which are the Ru / ZrxAlO catalyst and the Ru / CoZrxO catalyst, are prepared in the invention, and the catalysts are bifunctional heterogeneous catalysts having both a hydrogenation site and an acidic site.

Description

technical field [0001] The invention relates to the field of catalysts and their applications, in particular to the preparation, performance testing methods and applications of zirconium-containing supported nano-ruthenium catalysts. Background technique [0002] It is predicted that by 2030, 20% of transportation fuels and 25% of chemicals will be produced from lignocellulosic biomass, the only renewable carbon source capable of replacing fossil fuels. Lignocellulosic biomass is economical, abundant and has wide global availability. More importantly, lignocellulosic biomass is sustainably renewable and its derived monomers can be converted into fuels and many valuable chemicals. Currently, much research effort is devoted to developing efficient catalytic conversion pathways for the production of renewable fuels and chemicals from lignocellulosic biomass. As one of the most promising platform molecules for renewable fuels and value-added chemicals, γ-valerolactone (GVL) ha...

AI Technical Summary

Problems solved by technology

[0005] 1) The homogeneous catalyst used in the industrial hydrogenation of levulinic acid to γ-valerolactone is difficult to prepare, the cost is high, the reaction conditions are harsh, the catalyst recycling effect is poor, and it is difficult to recycle

[0006] 2) Although the commonly used noble metal catalysts such as Ir, Rh, and Pt have good catalytic performance and cycle availability, they are very expensive, which will greatly increase the production cost

In addition, factors such as the use of volatile organic additives, high-pressure operation, etc. limit their application in industry

[0007] 3) Industrial non-precious metal catalysts contain metal elements such as Cu, Ni, Cr, etc., and there are problems such as high catalyst toxicity, high dosage and low activity, too harsh reaction conditions and easy leaching of active metals.

In particular, a large amount of coke is easily produced during the catalytic reaction, which will undoubtedly increase the separation and purification process and cost

[0008] 4) Ruthenium-based noble metal catalysts with relatively low prices usually have the best activity and selectivity, but there is a problem of poor catalyst stability. The performance of supported nano-ruthenium catalysts depends greatly on the choice of support, and some supports cannot achieve The high dispersion of metal nanoparticles cannot prevent the sintering of catalyst precious metals and the formation of coke

[0009] 5) For supported nano-metal catalysts, higher hydrogen pressure will make it difficult to control the degree of hydrogenation of levulinic acid, which leads to the generation of a large number of by-products

The intermediate product after hydrogenation of levulinic acid needs to be acidified, dehydrated and closed at high temperature, but the acidic sites of the carrier are difficult to adjust, which greatly reduces the selectivity of the target product γ-valerolactone

[0010] 6) The catalyst needs to work effectively at a higher temperature and hydrogen pressure, which requires high requirements on the reaction vessel. Under harsh conditions, the catalyst is prone to irreversible deactivation, and at the same time, the risk factor of the reaction is very high, thereby increasing the production cost

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