Comparative study of vapour phase glycerol dehydration over different tungstated metal phosphate acid catalysts

Abstract

Tungstated metal phosphate (WO_x/MP; M = Al, Zr and Ti) solid acid catalysts were examined for vapor phase glycerol dehydration to acrolein and hydroxyacetone. The physico-chemical characteristics of the samples were explored using X-ray diffraction (XRD), N₂ sorption, Fourier-transform infrared spectroscopy (FT-IR), UV-visible diffuse reflectance spectroscopy (UV-DRS), and ex situ FT-IR investigation of the adsorbed pyridine and ammonia temperature programmed desorption (NH₃-TPD) analysis to gain an understanding of the impact of the structural and acidic nature of the catalysts upon changing the metal component. The catalytic activity and selectivity functionalities were interpreted in terms of the acidity and structural properties of the WO_x/MP catalysts. The outcomes demonstrated that WO_x/TiP was the most selective and stable catalyst during the catalytic dehydration of glycerol owing to the acceptable amount of surface acidity and the substantial number of pores available on its surface. A detailed study on WO_x/TiP was also performed to understand the interaction between the tungsten and the TiP support.