Synthesis and catalytic properties of highly ordered mesostructured silica-pillared α-zirconium phosphate: Self-assembly via interlayered templating method

Abstract

We present a facile organic surfactant templating self-assembly method with suitable cationic surfactant method for silica-pillared α-ZrP with ordered interlayered mesoporous structure. The synthetic silica-pillared α-ZrP powders with interlayer spaces and interlayer pore sizes ranging from 3.0 to 3.7nm and 1.4 to 2.1nm by varying the molar ratio of surfactant/α-ZrP during self-assembly process. The structure and properties of the silica-pillared α-ZrP powders were characterized by using XRD, SEM/TEM, FT-IR, TPD and N2 adsorption–desorption isotherms systematically. A bilayers arrangement-molecular micelles1 phase transformation formation mechanism was proposed for the molecular assembly. The acylation reaction of fatty acid methyl esters (methyl stearate) with ethanolamine to form monoethanolamides was chosen as a probe reaction to evaluate the catalytic activity of the resulting microspherical silica-pillared α-ZrP materials, which showed high activity, with about 92.9% methyl stearate conversion at 393K for 16h. The enhanced performance in the reaction is determined by the large surface area, ordered pore size and the increased number of acidic sites in the silica-pillared α-ZrP powders.