Molybdate-pillared hydrotalcites

Polyoxometalate-pillared hydrotalcites were also screened for activity for the dehydrogenation of t-butylethylbenzene to t-butylstyrene. Table III shows that molybdate-pillared hydrotalcites outperformed other pillared hydrotalcites. 

It was initially hoped that running the reaction under oxidative dehydrogenation conditions would lead to higher conversions. Studies with molybdate-pillared hydrotalcites under more optimized conditions showed that the presence of oxygen in the feed simply kept the catalyst from coking up as fast as if oxygen were not included. Unfortunately, even with the presence of oxygen in the feed, molybdate-pillared hydrotalcites were found to lose approximately 40% of their activity after 100-150 hours on stream. 

The results in Table II suggest that molybdate- and vanadate-pillared hydrotalcites contain both acidic and basic sites, the basic sites located on the metal hydroxide sheets, and the acidic sites located on the polyoxometalate pillars. 

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