Highly stable phosphine modified VOx/Al2O3 catalyst in propane dehydrogenation

The relatively low cost and mild toxicity of vanadium makes it an alternative to commercially applied Pt and Cr based catalysts in propane dehydrogenation (PDH). Conventional VO x /Al 2 O 3 catalyst shows high initial activity, but deactivates fast due to severe coke formation, which requires frequent regeneration by coke combustion and causes massive CO 2 emissions. In this context, we report on the phosphine (PH 3 ) surface modification of VO x /Al 2 O 3 catalyst leading to substantial improvement of its stability. The phosphorus considerably modifies the properties of the VO x /Al 2 O 3 catalyst: (i) tunes surface acidity, (ii) separates polymerized vanadium oxide species and (iii) weakens interaction between vanadium species with alumina support. Synergy among all these factors facilitates desorption of produced propylene and inhibit the oligomerization of coke precursors, which contributed to the enhancement of the catalyst stability during propane dehydrogenation.