Dehydration of sorbitol to isosorbide over hydrophobic polymer-based solid acid

Abstract A series of hydrophobic polymer-based solid acid catalysts PDS (x) were synthesized via hydrothermal synthesis method of sodium p-styrenesulfonate hydrate (SPSS) and divinylbenzene (DVB), followed by ion exchange. The specific surface area, acid sites concentration and hydrophobicity of the catalyst can be controlled by changing the amount of sodium styrene sulfonate, and the molar ration of SPSS and DVB from 0 to 0.4. Characterization results show that the PDS (x) catalysts have mesoporous structure (9.07–10.82 nm), large surface area (635–1039 m2/g), rich acidic sites (0.25–1.72 mmol/g), high thermal stability and super hydrophobicity. Assessed in the dehydration reaction of sorbitol to isosorbide, the catalyst shows a remarkable catalytic performance when the molar ratio of SPSS to DVB is 0.3, yielding up to 81.7%, at 150 °C, which is equivalent that of H2SO4. The catalyst can be recycled five times with no significant decrease in activity. The superior performance can be attributed to the unique polymer network and acidic property.