The use of lignocellulosic biomass to produce value-added chemicals like furfural, a platform chemical typically produced via acid-catalyzed dehydration of pentose sugars derived from hemicellulose, is gaining attention in the biorefinery industry. Cottonseed hulls (CSH), an abundant by-product of the cotton industry, represent a promising source for furfural production due to relatively higher hemicellulose content (11.6-24.5%) in comparison to hemicellulose content of other lignocellulosic biomasses such as wheat bran (22%), bagasse (16.52%), and hemp (10.60%). The objective of this study is to optimize the furfural production process using Box-Behnken design (BBD), a response surface methodology, to maximize furfural yield from CSH. The effects of three critical variables on furfural yield were systematically investigated: pre-treatment using varying ratios (5:1-15:1) of 1% H2SO4 to CSH (1% H2SO4:CSH); acid hydrolysis using varying concentration (2.5-7.5%) of H2SO4 to CSH (% H2SO4:CSH); and reaction time ranging from 30 to 90 min. Statistical analysis using ANOVA confirmed the model significance (p < 0.05) and revealed that all three variables (either individual or interaction) had significant effects on furfural yield. The optimized process conditions: pretreatment of 11.731 (1% H2SO4:CSH), acid hydrolysis of 6.74% (% H2SO4:CSH), and a reaction time of 81.2 min with desirability 1 resulted in a furfural yield of 14.34%. The study successfully demonstrates the application of BBD in optimizing the production of furfural from CSH, thus enhancing its potential as an economically viable feedstock for the biorefinery industry contributing to the advancement of biomass conversion technologies for the sustainable production of high-value chemicals.
