Selective metal catalyst for aminophenol

Abstract

The invention provides a preparation method and use of a selective metal catalyst for aminophenol. The preparation method comprises the following steps: (1) supporting metal nickel salt by using terbium oxide as a carrier, and then calcining in an air atmosphere to obtain terbium oxide-supported nickel oxide; (2) then, evenly mixing the compound, obtained in the step (1), with diacetyl ammonia andcarbon tetrachloride, and carrying out a reflux reaction in xylene to obtain a catalyst precursor coated with a nitrogen-containing polymer; or mixing the compound, obtained in the step (1), with glucose and a nitrogen-containing compound to obtain a catalyst precursor; (3) calcining the catalyst precursor at the high temperature of 500-1000 DEG C in an inert atmosphere to obtain the nitrogen-doped carbon-coated metal nickel selective metal catalyst for the aminophenol. The catalyst is used for catalyzing nitrobenzene for realizing the hydrogenation synthesis of p-aminophenol, and the conversion rate of the nitrobenzene and the selectively of the p-aminophenol can reach 100%.

Description

technical field [0001] The invention relates to a preparation method of a catalyst, in particular to the use of a selective metal catalyst for 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 . [0003] In order to ...

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