Exploratory Study on Thermal Microwave-Assisted Decomposition of Eucheuma Cottonii Carrageenan to 5-Hydroxymethylfurfural and Levulinic Acid in Aqueous Medium

Abstract

Carrageenan which is a renewable and abundant shows a potential as an energy feedstock. Carrageenan which can be extracted from Eucheuma cottonii can decompose to hydroxymethylfurfural (HMF) and levulinic acid (LA). This work is to study decomposition process of carrageenan to HMF and LA. Carrageenans were used and poured into microwave tube filled with sulfuric acid solution. The reactions were performed at a temperature (160–190°C), a loading concentration (0.025-0.15 g/mL) and batch times which is up to 120 min. The highest experimental HMF yield was 18.4 mol%, and LA was 29.7 mol%. The possible autocatalytic role of acetic acid (AA), formic acid (FA) and levulinic acid which were produced during the reaction, was investigated by conducting reactions in the presence of these acids. As a result, FA particularly shows a role as a catalyst.