Fig. 12
Yields of HMF and levulinic acid from crystalline, swollen, and gelatinized cellulose. Crystalline cellulose was suspended in TFA at − 20 °C for 15 h (0 h), with subsequent heating at 55 °C for up 5 h. Materials (100 mg) were suspended in 2 mL of 100 mM each of maleic acid and AlCl3; the reaction mixtures were heated to 180 °C and held at that temperature for 15 min. ND never-dried, FD freeze-dried. Levulinic acid yield is in blue, and HMF yield is in green. Error bars represent standard deviation for triplicates