Ketalization of glycerol with acetone to solketal over a phenolic resin-based solid acid

The ketalization of glycerol with acetone to (2,2-dimethyl-1,3-dioxolan-4-yl) methanol (solketal) is a potential method to produce a high added value glycerol derivative. Herein, a series of phenolic resin-based solid acids were fabricated by the copolymerization of 4-hydroxybenzenesulfonic acid (PhOH-SO3H) with various aldehyde monomers and applied as catalysts for the ketalization of glycerol with acetone to produce solketal at room temperature. The relationship between structural properties and catalytic performance of these phenolic resin-based solid acids for this reaction was investigated with the help of various characterization techniques and discussed in detail. It was found that the solid acid sample (PST-1.5) derived from terephthalaldehyde and PhOH-SO3H with molar ratio of 1.5:1 not only exhibited the highest glycerol conversion of 93 % with selectivity to solketal of 98 % under the optimal reaction conditions, but also showed excellent stability in glycerol conversion after five cycles. There is a competition between hydrophobicity and –SO3H density on the solketal yield, and the excellent catalytic performance of PST-1.5 was attributed to the synergistic effect of its weak hydrophilicity and rather abundant acid sites. [Display omitted] •The sulfonated phenolic resin is active to the ketalization of glycerol with acetone.•The highest glycerol conversion is 93 % with selectivity to solketal of 98 %.•Weak hydrophilicity and –SO3H density of the catalyst are the decisive factors for this reaction.•The hydrophilicity and –SO3H density of phenolic solid acid can be adjusted and controlled.•No obvious deactivation can be observed for phenolic solid acid catalyst.