Green process prorogue by xylanase enzyme and cellulose-derived sulfonated graphene oxide-like reinforcement in xylose and furfural production from corncob biomass

In this study, a process following the principles of green chemistry was applied for effective agricultural by-product conversion into biochemicals. Corncob was synergistically pretreated with a mixture of hydrogen peroxide:glacial acetic acid (1:2:2 wt/v/v) which was denoted as C-HPAC and then xylanase enzyme-assisted hydrolysis to obtain the highest xylose content of 1.99g with 66.41 % separation efficiency at 50 °C for 15h, and xylanase enzyme content of 0.4g/3g C-HPAC. Otherwise, the sulfonated graphene oxide-like structural material (EC-SGO) was synthesized through the sulfonation method using various concentrations of H2SO4 agent with EC-GO that was calcined with the mixture of ferrocene and cellulose (1:1 wt/wt) at 300 °C for 30 min. The highest furfural yield was 76.63 ± 2.23 % under the conditions of 60 mg EC-SGO catalyst, xylose concentration of 3 g/L, and NaCl 0.05 mol/L, at 180 °C in 60 min. Hence, the synergistic effect of NaCl and Brønsted acid sites (−SO3H) was confirmed through the XPS spectrum with an acid content of 0.6895 mmol/gcatalyst and depicted simultaneously a vital role through the proposal mechanism of converting xylose to furfural. The synthesized catalyst retains its stability for the multiple cycles of furfural production. Furthermore, this work has provided a route for the fractional separation of xylose and cellulose with assisted-enzymatic.