Effects of <i>p</i>-Toluenesulfonic Acid in the Conversion of Glucose for Levulinic Acid and Sulfonated Carbon Production

Abstract

This work investigates the possibility that valuable levulinic acid and sulfonated carbon could be produced in a one-pot reaction. p-Toluenesulfonic acid is used as an acidic catalyst as well as a sulfonating agent in the reaction, and its main effects are determined, depending on the water dosage. Relatively low water dosage is conductive to sulfonated carbon formation with high H+ exchange capacity and −SO3H intensity, good carbon framework, improved thermal stability and surface hydrophobicity, and good catalytic activity. In contrast, low water dosage is detrimental to levulinic acid yield. Under optimal reaction conditions, the total carbon utilization ratio of levulinic acid and sulfonated carbon reaches 70%. The sulfonated carbon shows good catalytic activity in the esterification of levulinic acid with ethanol, resulting in a high conversion ratio (93%).