High-efficiency and durable V-Ti-Nb ternary catalyst prepared by a wet-solid mechanochemical method for sustainably producing acrylic acid acetic acid-formaldehyde condensation.

Based on the precise phase control V species adjustment of vanadium phosphorus oxides (VPOs), a series of metal oxides (NbO, MoO, WO, and BiO) were selected as modification agents to further enhance the catalytic activity and retain the excellent durability of VPO-TiO-based catalysts for the new procedure of producing acrylic acid acetic acid-formaldehyde condensation. At an elevated liquid hourly space velocity (LHSV), the (AA + MA) selectivity reached 92.3% with a (MA + AA) formation rate of 63.8 μmol g min over the Nb-decorated catalyst (catalyst VTi-Nb), and it maintained good durability for up to 100 h. The detailed characterization results of XRD, Raman, XPS, NH-TPD, CO-TPD, and H-TPR, demonstrated that the addition of NbO could observably enhance the catalytic efficiency of the VPO-TiO catalyst. It not only improved the catalyst durability by enhancing prereduction of the V species, but also enhanced the active site density to improve the catalytic activity.