Tuning of Catalytic Dimethyl Adipate Hydrogenation by Changing Composition of Cu–ZnO–TiO₂ Catalysts

Abstract

Cu-based catalysts with different metal compositions were synthesized. Among the binary catalysts, the Cu–ZnO catalyst showed good performance. The synergistic effect of Cu+ and Cu0 produced by reduction of copper species was an important in the hydrogenation of dimethyl adipate (DMA). The addition of the third component was conducive to improving the dispersion of Cu; therefore, the ternary catalyst with different components was further prepared. Results showed that the spatiotemporal yield of CZT-2.0 (4:2:1) at 250 °C was 9.0 g·gcat–1·h–1, which may be related to the higher value of SCu0 and the larger dispersion of the Cu. The larger specific surface area of Cu0 provides more H· active species, increasing the concentration of the H· active species and further promoting DMA hydrogenation. Moreover, the more basic surface of the CZT-2.0 catalyst will adsorb more DMA molecules and have more basic sites. From the HR-TEM results, the CZT-2.0 catalyst arranged in an ordered pore structure of hexagonal zinc ore.