Well-Dispersed H3PW12O40/H4SiW12O40 Nanoparticles on Mesoporous Polymer for Highly Efficient Acid-Catalyzed Reactions

With the depletion of fossil fuels, development of renewable energy has attracted wide attention in recent years. The well-known polyoxometalates (POMs) of H3PW12O40 (denoted as PW12) and H4SiW12O40 (denoted as SiW12) are effective catalysts for acid-catalyzed reactions. Nevertheless, industrial application of PW12 and SiW12 is largely restricted by the agglomeration, separation, leaching and recycling issues. Moreover, the PW12 and SiW12 tend to deactivate strong proton sites due to the small surface area of 10 m2·g–1. To overcome these problems, the PW12 and SiW12 have been fabricated onto a mesoporous polymer of PDVB-VBC (compound 1) with a large surface area via tris(2-aminoethyl)amine (TAEA), resulting in the formation of new heterogeneous catalysts of PDVB-VBC-TAEA-PW12 (compound 3) and PDVB-VBC-TAEA-SiW12 (compound 4). Both compounds 3 and 4 possess mesoporous structures with high surface area of 121 m2·g–1 and 131 m2·g–1, respectively. And they have shown highly efficient and selective dehydration of fructose to 5-hydroxymethylfurfural (5-HMF) in dimethyl sulfoxide (DMSO) as well as esterification of lauric acid (LA) to methyl laurate. Moreover, the catalysts can be recycled for at least five times with no obvious decrease of reactivity. Therefore, such catalysts have great potential for further application from a chemical engineering point of view.