Effect of Reduction Temperature on the Performance of CuCo Bimetallic Catalyst Supported on Carbon-nitrogen Carrier for Hydrogenation of Oil to Fatty Alcohol

To address the issue of low yield in the production of fatty alcohols via the hydrodeoxygenation (HDO) pathway using single-metal Cu or Co catalysts, this study constructed a carbon-nitrogen-supported CuCo bimetallic catalyst system. The CuCo/CN catalysts were first prepared at reduction temperatures of 0, 150, 200, 300 ℃, respectively. Subsequently, stearic acid was used as a model substrate to evaluate the catalytic performance under reaction conditions of 220 ℃ and 3.0 MPa H₂ for 6 h. The results demonstrate that the CuCo/CN-200 catalyst, reduced at 200 ℃, exhibited the highest stearic acid conversion (85.1%), octadecanol yield (79.1%), and space-time yield (0.46mmol_alcohol∙g_cat⁻¹∙h⁻¹). XRD analysis revealed that the CuCo/CN-200 catalyst possessed smaller crystallite sizes, thereby exposing more active sites. XPS results indicate that electron transfer between Cu and Co enhanced the hydrogenation capability of the C=O bond. FT-IR spectroscopy confirmed that the CuCo/CN-200 catalyst exhibited stronger adsorption of carboxyl groups. When applied to the hydrogenation of natural oils, the CuCo/CN-200 catalyst maintained a stable fatty alcohol yield of approximately 70%, demonstrating excellent substrate adaptability. After five reuse cycles, the octadecanol yield decreased by only 13.6%, highlighting its superior catalytic stability. This study provides theoretical insights and optimization strategies for the design of highly efficient non-noble metal catalysts.