Preparation method of butanediol secondary hydrogenation catalyst by butynediol two-step hydrogenation

Abstract

The invention provides a method for preparing a butanediol secondary hydrogenation catalyst through adopting the butynediol two-step hydrotreation, and the method comprises the following steps: an accelerant is introduced into an alumina carrier; the carrier is heated; mixed nickel complex solution containing organic nickel salt, inorganic nickel salt and surfactant is prepared; the mixed nickel salt solution is dipped on the heated carrier, and the catalyst product with the nickel content of 5-25 w% and the accelerant content of 0.001-6 w% can be obtained by drying, baking, deoxidizing and passivating. The catalyst can be used in the process of preparing the butanediol secondary hydrogenation by adopting the butynediol two-step hydrotreation, the carbonyl can be reduced to be lower than 0.2 mg (KOH)*g<-1>, and the contents of acetal and butylene glycol are enabled to be reduced to the lowest level. Through the subsequent rectification, the butylene glycol product with the purity more than or equal to 99.5 percent and the chromaticity lower than or equal to 10 AHPA can be produced.

Description

technical field [0001] The invention relates to a two-stage hydrogenation catalyst, in particular to a preparation method of a two-stage hydrogenation catalyst for 1,4-butynediol hydrogenation to 1,4-butanediol. Background technique [0002] The two-step hydrogenation of 1,4-butynediol to 1,4-butanediol involves the following process: the first step (also known as one-stage hydrogenation) generally adopts a suspended bed (or bubbling slurry bed), using Raney-nickel catalyst, low-pressure hydrogenation at 50-80°C, 1-3MPa hydrogen pressure, hydrogenation of 1,4-butynediol to 1,4-butanediol, while the solution contains butanol , unsaturated hydrogenation product butene diol, butene diol isomerization product 4-hydroxybutyraldehyde and acetal obtained by condensation reaction of aldehyde and alcohol; because 4-hydroxybutyraldehyde and acetal cannot pass rectification method to remove, the presence in the product affects the purity and quality of the product, and further high-pr...

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Problems solved by technology

Due to the pulverization of silica gel under the high pressure of the second stage reaction, the fine particles produced will cause the pressure fluctuation of the reactor, resulting in the occurrence of parking accidents

The poor stability of the catalyst greatly affects the normal production

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