Cooperative Dual Hydrogen Donor System for Hydrodeoxygenation of Lignin Derivatives over NiAl Catalyst

ABSTRACT

The transformation of lignin into value‐added chemicals offers a promising strategy for sustainable carbon utilization. However, the hydrodeoxygenation of lignin derivatives remains a significant challenge, particularly due to the reliance on high‐pressure molecular hydrogen and noble‐metal catalysts. In this work, a highly active and efficient non‐noble metal‐based NiAl (NA) catalyst was developed for the hydrodeoxygenation of lignin‐derived compounds. The NA catalyst was synthesized via calcination followed by reduction of the NA‐LDH precursor. Detailed structural, compositional, surface, and morphological analyses were carried out to gain deep insights into the catalyst's properties. The NA catalyst demonstrates excellent activity for vanillin HDO, achieving 95% vanillin conversion and 93% yield of 2‐methoxy‐4‐methylphenol (MMP) at 180°C in 5 h. Moreover, several control and poison reactions were conducted to confirm the dual cooperative effect among hydrogen sources, Ni nanoparticles, and mixed‐metal oxide support. The NA catalyst exhibits excellent catalytic activity for a variety of lignin‐derived substrates. Additionally, the NA catalyst shows good recyclability for multiple cycles with a gradual decline in catalytic activity. The developed reaction protocol shows excellent values for the environmental factor (3.53) and mass intensity (2.52). Hence, this work has potential to enable green and sustainable conversion of biomass‐based compounds into value‐added chemicals.