Capturing Coke Precursors in a Pd Lattice: A Carbon-Supported Heteropoly Acid Catalyst for the Dehydration of Glycerol into Acrolein

Supported heteropoly acid catalysts are frequently used in the dehydration of glycerol into acrolein because of their high activity. However, they are easily deactivated by coke that can become deposited on the catalyst surface. Herein, we report a technique that significantly decreases coke formation by capturing coke precursors in a Pd lattice. The Pd-added H3PW12O40/C catalyst (Pd-PWC) showed stable catalytic activity and the amount of deposited coke formed was decreased to about 40?% of that without Pd addition. The catalysts were characterized by XRD, HR-TEM, XPS, NH3-TPD, and TGA methods. These results showed that the palladium lattice on the carbon support was easily loosened and that coking precursors were incorporated into the Pd lattice of the catalyst under the reaction conditions used. Consequently, the amount of coke that was deposited onto the active sites of the catalysts was significantly decreased.