Forming a Cu-Based Catalyst for Efficient Hydrogenation Conversion of Starch into Glucose

Abstract

A pellet-forming as-catalyst, CuO/Al2O3, was prepared by the precipitation–tablet molding method and characterized by the Brunner–Emmet–Teller (BET), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM) techniques and TEM. The characterization results showed that the formed CuO/Al2O3 was in situ reduced to Cu/Al2O3 and Cu2O/ Al2O3 catalysts in the reaction system. The catalytic performance of catalyzing hydrogenation starch into glucose was investigated in an autoclave over CuO/Al2O3. The yield of glucose reached 83.16% at a temperature of 160 °C, a pressure of 1.8 MPa, a 100 g starch solution of 15 wt%, a catalyst dosage of 2.25%, a reaction time of 4 h, and a rotational speed of 630 r/min. The reusability of the catalyst was evaluated, and the glucose yield did not decrease obviously even after being reused for five consecutive cycles. Starch was converted into glucose through the synergistic action of Cu+ and Cu0 catalysis. This work is expected to provide valuable insights into the design of catalysts and the hydrogenation process for efficient starch hydrogenation.