Microwave‐Assisted Hydrothermal Synthesis of CuO–ZnO–ZrO2 as Catalyst for Direct Synthesis of Methanol by Carbon Dioxide Hydrogenation

• Published in: Energy technology (Weinheim, Germany) Germany), 2017-11, Vol.5 (11), p.2100-2107
• Main Authors: Huang, Chong, Mao, Dongsen, Guo, Xiaoming, Yu, Jun
• Format: Article
• Language: English
• Subjects: Adsorption; Carbon dioxide; Catalysis; Catalysts; Catalytic activity; Chemical synthesis; Copper; Copper oxides; Dispersion; Hydrogenation; Methanol; microwaves; Nitrous oxide; Oxides; Physicochemical properties; Selectivity; Spectroscopy; Spectrum analysis; supported catalysts; Surface area; Surface chemistry; Temperature; X-ray spectroscopy; X-rays; zinc; Zinc oxide; Zirconium dioxide
• ISSN: 2194-4288; 2194-4296
• DOI: 10.1002/ente.201700190

A series of CuO–ZnO–ZrO2 catalysts was prepared by a facile microwave‐assisted hydrothermal synthesis method and used for the direct synthesis of methanol by CO2 hydrogenation in a fixed‐bed reactor at 240 °C, 3.0 MPa, CO2/H2=1:3 (v/v), and space velocity of 2400 mL gcat−1 h−1. The effects of the hydrothermal synthesis temperature (80–150 °C) on the physicochemical properties and catalytic activity of the CuO–ZnO–ZrO2 catalysts were investigated by using several techniques, including XRD, N2 adsorption, reactive N2O adsorption, SEM with energy‐dispersive X‐ray spectroscopy, X‐ray photoelectron spectroscopy, temperature‐programmed reduction by H2, and the temperature‐programmed desorption of adsorbed CO2 and H2. The catalyst prepared at 120 °C possessed a high surface area, a high dispersion of Cu species, a high adsorption capacity for CO2 and H2, and thus exhibited a high CO2 conversion and methanol selectivity. The surface area of metallic Cu (SCu) is the critical factor in determining the activity of the CuO–ZnO–ZrO2 catalyst. Microwave catalyst: The performance of a CuO–ZnO–ZrO2 catalyst prepared by microwave‐assisted hydrothermal synthesis is influenced greatly by the hydrothermal synthesis temperature. The catalyst prepared at 120 °C possesses a high surface area, high dispersion of Cu species, high adsorption capacity for CO2 and H2, and thus a high CO2 conversion and methanol selectivity.