A preparing method and uses of a hydrogenation catalyst

Abstract

A preparing method and uses of a hydrogenation catalyst are provided. The method includes (1) loading cerium oxide that is adopted as a carrier with a metal nickel salt, and performing calcination in an air atmosphere to obtain nickel oxide loaded by the cerium oxide; (2) fully mixing the compound obtained in the step (1) with ethanediamine and carbon tetrachloride and refluxing and reacting the mixture in xylene to obtain a nitrogen-containing polymer clad catalyst precursor, or mixing the compound obtained in the step (1) with glucose and a nitrogen-containing compound to obtain a catalyst precursor; and (3) subjecting the catalyst precursor to high-temperature calcination at 500-1000 DEG C in an inert atmosphere to obtain the nitrogen-doped carbon-clad metal nickel hydrogenation catalyst. The catalyst is used for catalyzing hydrogenation of nitrobenzene to synthesize p-aminophenol, and the conversion ratio of the nitrobenzene and selectivity of the p-aminophenol can all reach 100%.

Description

technical field [0001] The invention relates to a preparation method of a catalyst and its use for catalyzing the hydrogenation of nitrobenzene to synthesize p-aminophenol. Background technique [0002] p-Aminophenol is an important organic intermediate widely used in medicine, dyestuff and rubber and other fields. At present, the industrial production process of p-aminophenol is mainly produced in one step by catalyzing the hydrogenation of nitrobenzene in a strong acidic solution. The catalyst used in this process condition is usually a supported noble metal platinum or palladium catalyst, nitro The conversion rate of benzene can reach 90%, and the selectivity of p-aminophenol is about 85%. However, in a strongly acidic reaction medium (usually 15wt.% sulfuric acid aqueous solution), the noble metal may be poisoned and the active components will also be lost, which will have a negative impact on the service life of the catalyst and the control of production costs . [0...

AI Technical Summary

Problems solved by technology

However, in a strongly acidic reaction medium (usually 15wt.% sulfuric acid aqueous solution), the noble metal may be poisoned and the active components will also be lost, which will have a negative impact on the service life of the catalyst and the control of production costs

[0003] In order to improve the production process under such strong acidic conditions, it has also been proposed to use solid acid instead of liquid sulfuric acid to catalyze the hydrogenation of nitrobenzene to synthesize p-aminophenol in aqueous solution, thereby reducing the loss of active components. However, this process design requires A large amount of solid acid is added, and the active components of precious metals are still exposed to the acidic environment, so the loss of active components cannot be avoided; in addition, the use of solid acids instead of sulfuric acid will reduce the selectivity of p-aminophenol

Images