In‐Situ Engineering of MWW Zeolite to ITQ‐2‐M Composites for Conversion of Biomass Derived Molecules

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ABSTRACT Transition metal oxy‐hydroxide (Ni, Fe, Co, Mo, and V)‐decorated ITQ‐2 composites were synthesized in‐situ via controlled delamination of layered MCM‐22(P) under optimized pH, generating highly accessible active sites with minimal diffusion limitations for biomass ‐derived molecules. The in‐situ delamination strategy avoids multistep post‐synthetic incorporation, ensuring maximum metal loading, strong anchoring, and structural integrity. Structural characterization confirmed nanosheet formation through the disappearance of the (002) interlayer reflection and broadening of intralayer reflections (220), (310)) in the X‐ray diffraction (XRD) pattern and an increase in external surface area (90 to ∼300 m 2 /g) and mesopore volume (∼0.02 to 0.40 cm 3 /g) from N 2 sorption. Field emission scanning electron microscopy (FE‐SEM) revealed a morphological transformation from stacked layers to dispersed platelets. The TEM/HR‐TEM showed uniform slit like layers (∼2.5 nm) decorated with transition metal species (1.5–4 nm). XPS studies established the existence of Ni, Fe, and Co in +2 oxidation states, whereas V and Mo existed as V 5+ and Mo 6+ species, respectively. Catalytic studies demonstrated bifunctionality: ITQ‐2‐Ni‐4 enabled complete hydrogenation of levulinic acid to γ‐valerolactone (97% selectivity) via enhanced H 2 spillover and uniform Ni dispersion. ITQ‐2‐V‐8 and ITQ‐2‐Fe‐2 achieved > 85% conversion in iso ‐eugenol oxidation to vanillin through redox cycling and peroxo‐species formation (> 90% selectivity). Though promising in activity, performance could be improved under continuous‐flow vapor‐phase conditions to mitigate coke deposition.

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