Sulfonated hierarchical ZSM-5 zeolite monoliths as solid acid catalyst for esterification of oleic acid.

Sulfonated hierarchical H-ZSM-5 monoliths were synthesized via ice-templating as solid acid catalysts for biodiesel production. Characterization confirmed successful –SO₃ group grafting, increasing acid density. The catalysts achieved over 90% conversion of oleic acid in esterification, with easy recovery and reuse, and the relationship between porosity and acid density was explored. [ABSTRACT FROM AUTHOR]