FeCl3 and acetic acid co-catalyzed hydrolysis of corncob for improving furfural production and lignin removal from residue

In order to increase furfural yield and lignin removal, both FeCl3 and acetic acid were used to co-catalyze the hydrolysis of corncob. A series of experiments were carried out to investigate the effects of acetic acid, FeCl3 concentrations and temperatures on furfural production and residue characteristics. The results showed that high FeCl3 concentrations caused serious cellulose degradation while acetic acid was more effective for lignin removal. A maximum furfural yield of 67.89% (35.74% higher than that in conventional sulfuric acid-catalyzed process) was obtained at 180 °C in the presence of 20 mM of FeCl3 and 3% of acetic acid. Simultaneously, lignin removal reached 54.79%, and 74.29% of the cellulose was remained for further utilization. Acetic acid and FeCl3 co-catalyzed hydrolysis was not only a high efficiency and environmental friendly technique, but also provided a possibility to utilize the furfural residue for ethanol production and other industries.