Structure and catalytic consequence of Mg‐modified VOx/Al2O3 catalysts for propane dehydrogenation

Supported VO x catalysts are promising nonoxidative propane dehydrogenation (PDH) materials for their commercially attractive activity and propylene selectivity. However, they frequently suffer from rapid deactivation caused by coke deposition. This article describes the promoting role of magnesium on the stability of VO x /Al 2 O 3 catalysts for PDH. A series of VO x /Al 2 O 3 and Mg‐modified VO x /Al 2 O 3 catalysts were synthesized by an incipient wetness impregnation method. The catalysts were carefully characterized by Raman spectra, UV‐Vis spectra, STEM, TGA and in situ DRIFTS. We showed that the stability of a 12V/Al 2 O 3 catalyst was significantly improved on addition of small amounts of MgO. Experimental evidences indicate that V 2 O 5 nanoparticles emerge in the 12V/Al 2 O 3 samples, and appropriate Mg addition helps dispersing the V 2 O 5 nanoparticles into 2D VO x species thus decreasing coke formation and improving stability in nonoxidative dehydrogenation of propane. © 2017 American Institute of Chemical Engineers AIChE J , 2017