Supported ammonium metatungstate as highly efficient catalysts for the vapour-phase O-methylation of catechol with methanol

Ammonium metatungstate (AMT) impregnated SiO2, TiO2 and Al2O3 catalysts were found to be highly active and selective for the vapour-phase O-methylation of catechol with methanol. Particularly, the AMT/SiO2 catalyst with 7.9 wt% W content showed the highest catechol conversion (97.1%) and the highest guaiacol yield (88.1%).