Lignin-based solid acid catalyst for the conversion of cellulose to levulinic acid using γ-valerolactone as solvent

Abstract

Lignin was used as a carrier and loaded with ferrous sulfide to prepare a new type of solid acid catalyst for the catalytic conversion of cellulose to levulinic acid using γ-valerolactone as the solvent. The solubility characteristic of cellulose in γ-valerolactone was studied which proved that cellulose is physically soluble in γ-valerolactone. The performance of the new solid acid catalyst was evaluated in comparison with that of the commercial catalyst CMHT. The results showed that a high yield of levulinic acid (35.64%) was obtained at 185 °C in 120 min with lignin-based catalyst, when using CMHT under the same conditions, the highest yield of levulinic acid was 48.45%, which confirmed that the lignin-based solid catalyst can be used as a catalyst for the conversion of cellulose to levulinic acid. Finally, the pathway of the conversion of cellulose to levulinic acid using the new catalyst was analysed in detail for the first time. This research provides a new method for using lignin.