title: Comparative study of various pretreatment reagents on rice husk and structural changes assessment of the optimized pretreated rice husk.
abstract: The performance of alkalis (NaOH and Ca(OH)2) and acids (H2SO4, HCl, H3PO4, CH3COOH, and HNO3) in the pretreatment of rice husk was screened, and a suitable reagent was assessed for subsequent optimization using response surface methodology. From the assessment, HCl that hydrolysed rice husk well was optimized with three parameters (HCl loading, pretreatment duration, and temperature) using Box-Behnken Design. The optimized condition (0.5% (w/v) HCl loading, 125 °C, 1.5 h) is relatively mild, and resulted in ~22.3mg TRS/ml hydrolysate. The reduced model developed has good predictability, where the predicted and experimental results differ by only 2%. The comprehensive structural characterization studies that involved FT-IR, XRD, SEM, and BET surface area determination showed that the pretreated rice husk consisted mainly of cellulose and lignin. Compared to untreated rice husk, pretreated rice husk possessed increased pore size and pore volume, which are expected to be beneficial for fungal growth during fermentation.
authors.affiliation: Department of Chemical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Teck Nam
authors.initials: TN
authors.lastname: Ang
authors.forename: Gek Cheng
authors.initials: GC
authors.lastname: Ngoh
authors.forename: Adeline Seak May
authors.initials: AS
authors.lastname: Chua
mesh_terms: D000143:Acids / Q000494:pharmacology; D000468:Alkalies / Q000494:pharmacology; D000704:Analysis of Variance; D007202:Indicators and Reagents / Q000494:pharmacology; D012275:Oryza / Q000737:chemistry* / Q000187:drug effects*; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D014866:Waste Products / Q000032:analysis*
chemical_list: D000143:Acids; D000468:Alkalies; D007202:Indicators and Reagents; D014866:Waste Products