Ordered mesoporous copper-rare earth metal-aluminum composite oxide catalyst and application thereof

Abstract

The ordered mesoporous copper-rare earth metal-aluminum composite oxide catalyst disclosed by the invention has a highly ordered mesoporous structure and a relatively high specific surface area, and the copper and rare earth metal oxide and the aluminum oxide carrier are tightly interacted and are highly uniformly dispersed. The highly dispersed Cu active component provides a large amount of ethanol dehydrogenation activity or crotonaldehyde hydrogenation centers, and the highly dispersed rare earth metal oxide and the alumina carrier provide a large amount of acid-base active centers for promoting acetaldehyde aldol condensation, so that efficient conversion from ethanol to higher alcohol is finally realized. And meanwhile, the sintering and growth of the oxides of the Cu and the rare earth metals are limited by mutual doping and strong interaction among the oxides of the Cu, the rare earth metals and the aluminum, so that the catalyst shows excellent stability in 500-hour long-time evaluation.

Description

(1) Technical field [0001] The invention relates to an ordered mesoporous copper-rare earth metal-aluminum composite oxide catalyst (CuO-MO x -Al 2 o 3 ) and its preparation method and application, the catalyst shows excellent catalytic activity, selectivity and stability in the reaction of producing higher alcohols from ethanol, and thus has good industrial application prospects. (2) Background technology [0002] Due to the depletion of fossil resources and the greenhouse effect caused by their use, the development and utilization of renewable biomass fuels has attracted more and more attention. As a renewable biomass fuel, bioethanol is widely used as a gasoline blending component in the United States, Brazil, China and other countries. However, ethanol has problems such as strong hygroscopicity, low energy density, and corrosion of engine cylinders, so it is not an ideal gasoline blending component. Compared with ethanol, n-butanol is insoluble in water, has high ene...

AI Technical Summary

Problems solved by technology

Such as high specific surface CeO 2 The supported copper-based catalyst achieved 67% ethanol conversion and up to 30 wt% butanol yield at a reaction temperature of 250 °C, but it required supercritical CO 2 In the medium, the reaction pressure greater than 10MPa has higher requirements on the material of the reaction equipment, the reaction process is more complicated, and the production capacity of butanol per unit volume of the reactor is low, and its industrial application is restricted to a certain extent [Green Chem., 2015 ,17:3018-3025.]

Activated carbon supported Cu-CeO 2 / AC catalyst is used in the reaction of ethanol dehydrogenation and condensation to produce n-butanol, which can be 2 ), LHSV=2h -1 Under the above reaction conditions, it showed 46% ethanol conversion and nearly 20wt% butanol yield, and no small molecular gas products were produced, but the catalytic activity decreased slightly in the long-term reaction evaluation [Chem.Commun., 2016, 52,13749-13752; Patent CN106076344]

[0004] Although copper-based catalysts are low in price and high in activity, copper nanoparticles are easy to sinter due to the weak interaction between the metal and the support, and the thermal stability and durability are poor [Prog.Solid State Chem.,1975,9,21 -25.]

Images