Influence of Intercalation-Exfoliation-Reduction Technique towards the Physico-Chemical of VPO Catalysts

الملخص EN

Four VPO catalysts were synthesized through intercalation and exfoliation in various alcohols and subsequent reduction of the exfoliated VOPO4 sheets with various alcohols to produce VOHPO4⋅0.5H2O.

The resulting VOHPO4⋅0.5H2O that undergoes the intercalation-exfoliation-reduction (IER) process will be further activated into VPO catalysts, and addition of 1 mole % Bi(NO3)3⋅5H2O in the first stage of this experiment has also being investigated.

The synthesized materials were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and temperature-programmed reduction (TPR) in H2.

Catalytic evaluation of the IER-treated and Bi-doped VPO catalysts was also studied on microreactor.

The VPO catalyst produced through IER using 2-butanol and ethanol with addition of Bi, IERC(2Bu-Et)RBi1, gave the highest MA selectivity due to reactive O2− species released from the additional crystalline V5+ phase formed by doping 1% bismuth as promoter (O2−-V5+ pair) at relative lower temperature.

Nevertheless, the VPO catalyst produced through IER using isobutanol, IERC(isoBu), gave the highest activity due to high amount of reactive O− species released from V4+ phase (O−-V4+ pair) whereby the IERC(isoBu) catalyst synthesized consists of high percentage of V4+ (93 %).