In-situ phosphorized catalyst for preparing cycloalkane from lignin as well as preparation method and application of catalyst

Abstract

The invention relates to a cycloalkane catalyst prepared from lignin through in-situ phosphorization and a preparation method and application of the cycloalkane catalyst, Cu-Mg-Al hydrotalcite serves as a precursor of the catalyst, a Cu / CuMgAlOx intermediate is obtained through calcination and reduction, and then the catalyst is prepared through in-situ phosphorization. The preparation method specifically comprises the following steps: respectively dropwise adding a mixed solution containing Cu < 2 + >, Mg < 2 + > and Al < 3 + > and a NaOH solution into a Na2CO3 solution, controlling the temperature and pH of the mixed solution, and precipitating; after dropwise adding is finished, aging, filtering, washing and drying the mixed solution in a stirring state to obtain a precursor; grinding the precursor into powder, and calcining to obtain a metal oxide; metal oxide is reduced and activated to obtain an intermediate, and mixed powder of red phosphorus and the intermediate is subjected to in-situ phosphorization in an inert atmosphere to obtain the catalyst. The catalyst has high catalytic activity on deep deoxidation of cycloalcohol intermediates in the lignin conversion process, and the yield and selectivity of cycloalkanes in the product are improved.

Description

technical field [0001] The invention belongs to the field of lignin conversion, and relates to an in-situ phosphatized lignin-to-cycloalkane catalyst and a preparation method and application thereof. Background technique [0002] Lignin is one of the main components of lignocellulosic biomass, which is composed of aromatic rings connected by carbon-carbon bonds and aromatic ether bonds. Its unique aromatic chemical structure makes it an effective source of naphthenic hydrocarbons. The conversion of lignin into naphthenes generally requires two steps: the first step is to break the carbon-carbon bonds and ether bonds between the aromatic rings of the lignin, so that the lignin macromolecules are depolymerized into single benzene ring products; the second step It is the hydrodeoxygenation of single benzene ring products, removing the oxygen-containing functional groups around the benzene ring and the unsaturated bonds of saturated benzene rings and branched chains. Among many...

AI Technical Summary

Problems solved by technology

[0005] During the preparation process of ex-situ phosphating method, there is pyrolysis to produce phosphine harmful gas, and direct discharge will pollute the environment. At the same time, the remaining elements after decomposition are mixed into the catalyst as impurities, which increases the washing cost of the catalyst.

The in-situ phosphating method can avoid the above problems, but the current in-situ phosphating method has harsh phosphating conditions (required temperature is too high) in the preparation process, making the method less economical