Liquid-phase alkylation of benzene with ethylene over postsynthesized MCM-56 analogues

MCM-56 analogues were postsynthesized via a mild acid treatment technique from hydrothermally synthesized MCM-22 lamellar precursors with Si/Al ratios of 15–45. The physicochemical properties of MCM-56 were characterized by XRD, SEM, N2 adsorption, XPS, 29Si and 27Al MAS NMR, NH3-TPD and pyridine adsorption IR techniques. In comparison to MCM-22 with 3-dimensional MWW topology, the postsynthesized MCM-56 showed a broad X-ray diffraction of emerged 1 0 1 and 1 0 2 reflections and possessed a structural disorder along the layer stacking direction. Composed of partially delaminated MWW nanosheets, MCM-56 analogues had a larger external surface than MCM-22. The MCM-56 and MCM-22 catalysts were employed in the liquid-phase alkylation of benzene with ethylene. MCM-56 analogues exhibited a higher yield of ethylated benzenes and a higher catalytic stability than MCM-22, proving to serve as promising solid-acid catalysts for processing bulky molecules in petrochemical industry.

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► MCM-56 analogues were postsynthesized from MCM-22 precursors with various Si/Al ratios.
► MCM-56 analogues possess a partially delaminated structure consisting of disordered collection of MWW sheets.
► MCM-56 analogues are more active and durable than MCM-22 in the alkylation of benzene with ethylene.