A green and efficient solid acid catalyst from coal fly ash for Fischer esterification reaction

A green and efficient solid acid catalyst (SAC) has been synthesized upon modification of F-type fly ash using ortho-phosphoric acid (35 wt. %). Catalyst characterization has been accomplished using different analytical techniques, such as FT-IR, XRD, SEM-EDS, and BET surface area analysis. SAC possessed excellent catalytic activity for Fischer esterification reaction between 4-aminobenzoic acid and methanol at 95 degrees C to produce methyl 4-aminobenzoate (MAB), an important precursor for the synthesis of pharmaceutical drugs, (+/-) martinelline, and (+/-) martinellic acid. This investigation suggests the utilization of fly ash to develop novel solid acid catalyst system for catalyzing industrially important esterification reaction. (C) 2015 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.