Synthesis of solketal from glycerol over modified SiO2 supported p-phenolsulfonic acid catalyst

Acetalization of glycerol with acetone could convert surplus glycerol into an important fuel additive (solketal). In this work, a stable solid acid catalyst was synthesized in a facile polycondensation of p-phenolsulfonic acid on KH560 modified SiO2 (PSF/K-SiO2) and used in the acetalization of glycerol at room temperature. Characterization results confirmed that PSF/K-SiO2 possessed larger surface area and surface acidity than that of PSF resin (copolymer of p-phenolsulfonic acid and formaldehyde) and non-modified SiO2 supported PSF resin (PSF/SiO2). As a result, PSF/K-SiO2 was extremely active and stable in the acetalization of glycerol. At 25 degrees C, the detected conversion of glycerol reached 86.3% with a 97.7% selectivity of solketal at 1.5 h. The best yield of solketal over PSF/K-SiO2 could reach 93.1 g-solketal/g-cat/h, and PSF/K-SiO2 could be recycled at least 5 times without obvious decrease in reactivity.

Automated summary

A stable solid acid catalyst, PSF/K-SiO2, was synthesized and demonstrated to be highly active and stable in the acetalization of glycerol at room temperature, achieving a high solketal yield with good recyclability.