Hydroxyl‐Rich Deep Eutectic Solvents Assistant Synthesis of VPO and Its Application in Selective Oxidation of n‐Butane

Abstract

AbstractDeep eutectic solvents (DESs) consisting of choline chloride (ChCl) and polyols (Ethylene glycol (EG), 1,4‐Butanediol (BDO), Glycerol (GL), and Xylitol (XYL)) as a green and effective promoter assisting the synthesis of vanadium phosphorus oxide (VPO) were innovatively proposed and investigated in detail for the selective oxidation of n‐butane to maleic anhydride (MA). The catalytic results showed that the performance of VPO catalysts was improved significantly with the addition of polyols DESs. A combination of techniques including SEM, TEM, XRD, FT‐IR, Raman, XPS, and TG‐DTA were employed to investigate the effect of DES on the structure of VPO. We correlated the structure of the catalysts with catalytic performance and found that the n‐butane conversion was positively correlated with the intensity ratio of I (020)/I (204) for catalysts, and the MA selectivity of VPO catalysts was negatively correlated with the vanadium average oxidation state on the catalyst surface.