Carbon-supported Pd/NiO-CoOx nanoparticles for highly selective and stable 1-nitroanthraquinone hydrogenation

Abstract

1-aminoanthraquinone has numerous applications in chemical industry, for example, it is an important intermediate for producing anthraquinone dyes. In this work, Pd/NiO/C, Pd/CoOx/C, and Pd/NiO-CoOx/C (C-carbon black) are prepared by room-temperature hydrazine hydrate and replacement reduction methods. All as-prepared catalysts have been characterized by XRD, SEM, TEM, HRTEM, XPS, STEM-EDX elemental mapping and line-scanning et al., The Pd-related species are highly dispersed on the nickel, cobalt or nickel-cobalt oxide nanoparticles (NPs), the interaction of Pd–NiO (or CoOx, NiO-CoOx) is present. Pd/NiO-CoOx/C provides 99.2 % conversion of 1-nitroanthraquinone and 91.0 % selectivity to 1-aminoanthraquinone for 1-nitroanthraquinone hydrogenation under the following reaction conditions: H2 pressure-3.0 MPa, 60 °C, 4 h. The catalytic behaviors of Pd/NiO-CoOx/C for 1-nitroanthraquinone hydrogenation are much better than Pd/NiO/C and Pd/CoOx/C mainly due to the interaction of Pd–NiO-CoOx, synergy effect of Pd and NiO-CoOx, and high Pd dispersion.