Ni Nanoparticles Supported Montmorillonite Clay for Selective Catalytic Transfer Hydrodeoxygenation of Vanillin into 2-Methoxy-4-methylphenol

The targeted catalytic transfer hydrodeoxygenation (CTHDO) of vanillin (VAN) to 2-methoxy-4-methylphenol (MMP) holds promise as a noteworthy subject in the domain of bio-oil utilization, offering potential as a future biofuel and finding versatile use in fragrances and pharmaceutical industry. In this study, stable, cost-effective Ni nanoparticles supported on montmorillonite (MMT) clay was synthesized for eco-friendly, alcohol-mediated CTHDO of VAN to MMP. The Ni(10 %)/MMT catalyst achieved >99 % VAN conversion and 95.2 % MMP selectivity using isopropanol (IPA) as a solvent and hydrogen donor. Characterization encompassing PXRD, SEM, TEM, and XPS confirmed successful Ni integration onto MMT. NH3-TPD, pyridine-IR, and H-2-TPR analysis evaluated catalyst surface acidity and reducibility. The synergy between surface-modulated acidity of MMT and Ni nanoparticles collectively facilitated IPA and VAN activation, driving CTHDO performance. The Ni(10 %)/MMT catalyst displayed sustained activity over five recycles. Its exceptional stability and performance underscore its potential as an eco-friendly, sustainable, non-noble transition metal-based catalyst for the hydrogenating lignin bio-oil model compounds, contributing to greener catalytic advancements.