Heterogeneous para-phenylamino sulfonic acid ligand functionalized on MCM-41 derived from rice husk ash: Selective mono-alkylated products of tert-butylation of phenol

•3-(4-Amino-phenylamino)-propane-1-sulfonic acid was functionalized on MCM-41.•The functionalized material had a high surface area of 468 m2 g−1.•The hybrid material was used in the tert-butylation of phenol.•The catalytic alkylation of phenol with tert-butanol (TBA), lead to 99.5% conversion.•XRD showed the structure of MCM-41 remained intact after the catalytic reaction.

A new organo-inorganic hybrid material was prepared by immobilizing 3-(4-aminophenylamino)propane-1-sulfonic acid onto functionalized mesoporous MCM-41 via simple post-synthesis method. The hybrid organo MCM-41 preserved its hexagonal honey-comb configuration after both surface chemical modification and immobilization of sulfonic acid ligand. XRD analysis exhibited three well-resolved diffraction peaks corresponding to the highly ordered mesostructure. The five intense carbon peaks of solid-state CP-MAS 13CNMR spectroscopy confirmed the grafting of sulfonic acid ligand onto the well-structured MCM-41. Surface properties of the material revealed a pore size of 1.98 nm and surface area of 468 m2 g−1. The catalytic performance of this hybrid material was tested in the alkylation of phenol with tert-butanol (TBA) and showed a high catalytic activity leading to 99.5% conversion of tert-butyl alcohol and high selectivity to monoalkylated products.

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