Optimized hydrogen production via dry methane reforming with Ni/Al2O3 catalysts modified by cobalt and Boron: A design of experiments approach for enhanced performance

In this study, seven catalysts were designed, synthesized, and evaluated using the Design of Experiments (DOE) approach. The catalysts included one nickel (Ni) catalyst as a standard, two Ni catalysts promoted with boron trioxide (B₂O₃), two bimetallic catalysts in Ni-Cobalt (Co) systems, and two bimetallic catalysts also promoted with B₂O₃, all supported on γ-alumina. The γ-alumina support was synthesized via the microwave-assisted combustion method, while the metals and non-metallic promoter were incorporated using incipient wetness impregnation. The catalysts were thoroughly characterized by X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Field-Emission Scanning Electron Microscopy (FE-SEM), physisorption of N₂ and Temperature-Programmed Reduction (TPR). Activation was performed at 700 °C for 1 h under hydrogen (H₂) flow. Catalytic performance was tested in a fixed-bed quartz reactor coupled with a gas chromatograph over 12 h at a space velocity of 96 L g⁻¹ h⁻¹. Carbon formation was analyzed by XRD and Raman spectroscopy, revealing a lower degree of crystalline carbon with a disorder index of 1.29 in the sample containing the highest B₂O₃ content. Thermogravimetric analysis (TG) quantified the reduction in carbon production by up to 57.7 %, demonstrating that B₂O₃ significantly reduced coke deposition. The results indicate that the catalysts with all three components exhibited high stability, enhanced catalytic activity, and minimized coke formation. A cubic special predictive model, with an Fcalculated/Ftabulated ratio of 41.12, demonstrated high statistical significance as confirmed by the Fisher test.