Microwave irradiation assisted intensive and quick delignification of lignocellulosic biomass, and confirmation by spectral, morphological and crystallinity characterization.

The purpose of this work was to use a microwave-assisted technique to improve and accelerate lignin removal from rice straw biomass. Using a Box-Behnken experimental design, the effect of four critical process parameters, viz. microwave power (480-800 W), irradiation time (4-12 min), bleaching solution concentration (0.4-3.0 %), and bleaching time (1-5 h) on the delignification (%) was investigated, and the process was optimised using response surface methodology. The experimental data best fitted a quadratic model with an R2 of 0.9964. The optimized value of process parameters (in aforementioned sequence) was found to be 671 W, 8.66 min, 2.67 %, and 1 h respectively, for the best delignification of 93.51 percent.The absence of lignin peaks (1516 and 1739 cm-1) was corroborated by deconstructed morphological structure and higher crystallinity in the optimised delignified sample (53.7 %).

Application of genetic algorithm in modelling and optimization of cellulase production.

The aim of this work was to study the application of genetic algorithm (GA) in modelling and optimization of cellulose production by Trichoderma reesei from pea hull. Enzyme activity of cellulase was determined using Filter Paper Activity (FPA) assay. Optimization of process parameters was performed using mathematical (MO) and genetic optimizers to obtain combination of variables for highest possible enzyme activity. GA generated a higher value of cellulase activity (0.353 U/mL) as compared to MO (0.302 U/mL). The values of independent variables in set (GA, MO) were: agitation speed (127, 120 rpm), %H2O2 concentration (10.36, 5.0), cultivation time (112, 91 h). The investigation highlights that GA could be used as a potential optimizer for processes involving waste utilization.