Abstract

Microwave-assisted preparation of bimetal ZnO-SiO2-pillared montmorillonite using Indonesian natural montmorillonite has been performed. The preparation was proceeded by directly dispersion of zinc oxide and tetraethyl ortho silicate as silica precursors into montmorillonite suspension with tetramethyl ammonium hydroxide followed by microwave irradiation. The effect of zinc content in the nanocomposite was studied by investigating the structure, surface textural, and surface acidity by employing x-ray diffraction (XRD), scanning electron microscopy-energy dispersive x-ray (SEM-EDX), gas sorption analysis, and pyridine adsorption-Fourier-transform Infra-Red (FTIR) method. The results of characterization notified the increasing basal spacing d001 of montmorillonite from 1.27 nm into 2.72 nm and 2.43 nm for zinc content of 5 mmol/g and 10 mmol/g, respectively. The higher zinc content is attributed to the increasing specific surface area and surface acidity which contributed to the significantly increasing catalytic activity. The conversion of 99.99% and selectivity to produce isopulegol of 66.39% were achieved as optimum activity of the time-efficient prepared pillared montmorillonite.

Keywords

References

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