In the production of polyamides, Platinum-palladium on carbon catalyst is used to produce hydroxylamine from nitric acid as raw material, aniline hydrogenation to dicyclohexylamine, halogenated aniline reduction alkylation, hydrazone hydrogenation to hydrazine, fatty nitrile (R-CN) hydrogenation to primary amine (RNH2), and nitroso aromatic compounds hydrogenation to aniline.