TiO2 and SiO2 supported Wells-Dawson heteropolyacid H6P2W18O62 as the catalyst for ETBE formation

Catalysts containing 5–25 wt.% of Wells-Dawson heteropolyacid H6P2W18O62 supported on silica and titania (anatase) differing by the surface area and porosity were investigated using XRD, FTIR spectroscopy and catalytic tests. They were active and selective in gas-phase synthesis of ethyl-tert-butyl ether (ETBE) at temperatures as low as 40 °C. It has been demonstrated that the heteropolyacid H6P2W18O62 is present at the support surface predominantly in form of nanocrystallites exhibiting higher activity than that, pure, in form of the microcrystallites (a few μm thick).