Efficient Alkaline Peroxide Pretreatment of Sterculia foetida Fruit Shells for Production of Reducing Sugar: Effect of Process Parameters on Lignin Removal

Abstract

The efficient delignification of low-cost lignocellulosic biomass is of utmost importance for its viable conversion to biofuel. In the current study, agricultural waste biomass of Sterculia foetida fruit shell was pretreated by heating at 60 ℃ and 121 ℃ in the presence of alkaline and alkaline peroxide conditions. The objective was to study the effects of concentration of NaOH & H2O2 and temperature on lignin removal efficiency and reducing sugar content. The structural and functional changes caused to the biomass were also studied using FTIR and XRD analysis. The optimum lignin removal of 81.66% was achieved by heating at 60 ℃ for 3 hours using 3% H2O2 and 5% NaOH aqueous solution showing an increase in crystallinity of the pretreated samples, removal of lignin as well as easy accessibility of cellulose and also indicates reduction of yield due to in situ degradation of the released sugars in the presence of NaOH and H2O2 at higher chemical concentrations. The developed pretreatment procedure showed appreciable delignification of the biomass which could be easily scaled up for continuous operations at low costs.