Synthesis and characterization of MCM-41-SO₃H organic-inorganic hybrids

A novel method to introduce sulfonic acid groups directly into MCM-41 by direct synthesis and post-synthesis modification is presented. Their activity as acid catalysts for the acetalization of benzaldehyde and ethylene glycol is examined. The mesoporous organic-inorganic hybrids prepared by the methods have uniform mesopores and high surface area. These hybrids also show high activity for the acetalization. The post-synthesis modified hybrid has higher activity than the directly synthesized hybrid, which is consistent with its higher number of acid sites.