Synthesis of hierarchical ZSM‐5 using polymer macro template for selective C‐alkylation of m‐cresol with tert‐butanol

Abstract

AbstractThe present study reports nanocrystalline hierarchical zeoite ZSM‐5 as a potential alternative to homogeneous catalysts for the liquid phase tert‐butylation of m‐cresol. Polydiallyldimethylammonium chloride macro‐template was used to develop vacuum‐concentration dual template nano‐precursors by hydrothermal process. The catalytic performance was analyzed for the given reaction and the high percent conversion of reactants with excellent selectivity towards the ortho isomer, 2‐tert‐butyl‐5‐methylphenol was recorded. In contrast, the low activity and selectivity towards the tert‐butylation of m‐cresol, and the selectivity towards the desired product are noticed with the nanocrystalline zeolite ZSM‐5 synthesized without macro‐template. In addition, the catalyst is recoverable due to its robust nature, which indirectly reduces industrial wastage. Various parameters that affect the rate of the reaction were optimized. Kinetic analysis studies showed that the reaction followed first‐order kinetics with respect to tert‐ and the reaction obeyed the Langmuir‐Hinselwood mechanism. The activation energy was determined as 43.0 ± 0.2 kJ/mole. The study reveals that nanocrystalline hierarchical zeolite ZSM‐5 is an efficient, selective, simple, economical and environment‐friendly catalyst for the tert‐butylation of m‐cresol.