A new platinum catalyst based on poly{acrylamide-co-[3-(acryloylamino)propyltrimethylammonium chloride]} for the gas-phase reduction of nitrobenzene, phenol and the hydrodechlorination of aromatic compounds

In the following, the gas-phase hydrogenation of nitrobenzene, phenol and the hydrodechlorination of 1,2-chloronitrobenzene and 2-chlorophenol using a new platinum catalyst founded upon the title copolymer is described. It is shown that the catalyst is applicable up to a temperature of 180 degrees C. Differences in activity and selectivity with respect to a conventional Al2O3-based catalyst were disclosed. The major product of the hydrogenation of nitrobenzene is aniline, with cyclohexylamine and benzene as minor products. The reduction of phenol leads to cyclohexanone, as single product. The conversion of 1,2-chloronitrobenzene yields chloroaniline and aniline as products with selectivities depending on the temperature. 2-Chlorophenol is reduced mainly to cyclohexanone. This is interpreted by an electron transfer from nitrogen centers of the carrier to the catalytic active metal which influences the adsorption properties of the platinum particles. For the reduction of 2-chlorophenol a demonstration is given showing that the activity and selectivity of the catalyst can be changed by the use of palladium as active species.