Optimized biofuel production from Triplochiton scleroxylon sawdust via microwave-assisted pyrolysis and hydrocracking: Process analysis and production revenue forecasting with Aspen Plus

Abstract

Biomass has historically been a key fuel source for activities like cooking and heating for millennia, yet modern energy demands and environmental challenges necessitate advanced methods to convert lignocellulosic waste into sustainable fuels. Microwave-assisted pyrolysis and hydrocracking show promise for biofuel production; optimizing these for lesser-studied feedstocks like Triplochiton scleroxylon sawdust can improve yield, scalability, and cost-effective biofuel upgrading in biorefineries. After performing a physiochemical analysis of the sawdust, response surface methodology using a centered composite design was applied to examine how various pyrolysis determinants affect bio-oil generation and assist in establishing the best processing settings. The variables studied include microwave power, irradiation time, and the percentage of biochar employed for wave absorption. The findings revealed that Triplochiton scleroxylon sawdust possesses valuable properties for bio-oil formulation, featuring a substantial proportion of volatile components (74.2 ± 2%) with a reduced ash level (2.9 ± 0.5%). Enhancement results showed that all pyrolysis factors had significant impacts, with a 5% level of statistical significance. Peak bio-oil output, 34.6%, was realized under the following experimental settings: microwave power of 650 W, 20 min. of irradiation, and 20% absorbent intake. The resulting bio-oil had a pH of 4.8 ± 0.4, a water content of 22 ± 2.3%, and a heating value of 17.5 ± 0.8 MJ/kg. Considering an optimal desirability rate of 0.708, the hydrocracking plan design perspectives forecasted as production metrics: 183.7 kg/h of gasoline and 35.9 kg/h of biodiesel from 1 ton/h of sawdust with a total production cost of 163,848.183 CFA francs. These observations confirm Triplochiton scleroxylon sawdust as a viable, cost-effective source for scalable biofuel production.