Scilight Press

In this study, the impact of alkali and acid pre-treatments on the structure and composition of rice straw (RS), along with the biogas and methane production potential of the pre-treated substrates was investigated. XRD and Fourier Transform Infrared Spectroscopy demonstrated the partial decomposition of rice straw and alteration of lignin structure as an outcome of pre-treatment by un-bonding the ether chain inside lignin molecules. After pre-treatment with NaOH, hemicellulose and lignin significantly reduced up to 89.45 and 93%, respectively. Cumulative methane yield after 40 days of anaerobic digestion (AD) of RS pre-treated with 1, 2, 3 and 4% NaOH was 28.97, 55.78, 95.08 and 55.64%, respectively, higher than the untreated sample. The acid pre-treatment was not very effective in the enhancement of biogas and methane production. The findings of this study indicated that 3% NaOH pre-treatment had the potential to be an effective way to increase the viability of producing methane from rice straw.