Mesoporous poly(ionic liquid) solid acid for sequential dehydration of sorbitol to isosorbide

The catalytic conversion of the biomass platform compound sorbitol to isosorbide is an important reaction for the production of relevant renewable chemicals. The development of highly efficient heterogeneous catalyst materials offers promising perspectives for the sorbitol dehydration reaction. The complex competitive reactions, such as degradation and polymerization, are still a major challenge to obtain isosorbide in high yield. In this work, a series of ionic liquid functionalized polymer catalysts, P-[C3/4R]-SF, were successfully prepared by hydrothermal synthesis, which has a high surface area and strong acidity. And the catalysts were fully characterized by the N2 sorption-desorption isotherms, elemental analysis, water adsorption isotherms, FT-IR, TGA and 31P NMR, etc. As a result, the as-prepared P-[C3/4R]-SF catalysts exhibited excellent catalytic activity and stability under mild reaction condition (140 degrees C, 6 h). The yield of isosorbide is up to 75 %, and it still has good catalytic activity after five cycles. This work provides a synthesis method of ionic liquid functionalized polymer catalyst and its application in sorbitol dehydration reaction.