Carbon dioxide hydrogenation to methanol over polybenzoxazine-based mesocarbon supported Cu–Zn catalyst

Abstract

Carbonaceous material has been generally recognized as a stable and functionalized catalyst support and has a high surface area. It has been reported that the nitrogen species can enhance metal dispersion, leading to a promising catalytic activity. To achieve this goal, a high-surface-area carbon material, so-called “mesocarbon”, was synthesized via carbonization of polybenzoxazine (PBZ). The 15% CuZn/mesocarbon catalyst was prepared by an incipient wetness impregnation with equimolar concentrations of Cu and Zn and then its applicability in the direct methanol synthesis from CO₂ hydrogenation was tested. It was found that 15% CuZn/mesocarbon catalyst exhibited the highest methanol productivity (498 mg g_cat⁻¹ h⁻¹) and CO₂ conversion (28 ± 2%) at a reaction temperature and pressure of 240 °C and 15 bar, respectively. These high catalytic properties can be assigned to the high surface area of mesocarbon (up to 471 m² g⁻¹) and high nitrogen content (2.31%), which can prevent metal agglomeration and improve hydrogen dissociation.