Case Studies in Chemical and Environmental Engineering (Jun 2024)
Hydro-deoxygenation of waste biomass pyrolysates on cobalt-sulfided catalyst for the production of BTX fuels
Abstract
Biomass has supplanted traditional fuels as the principal renewable energy source due to its carbon neutrality. Because of its high viscosity, thermal instability, and undesired coke production, biomass oil has limited applicability; however, hydro-treatment procedures can address these drawbacks and produce bio-oil fuels that meet industry standards. Consequently, compounds containing hydroxyl entities, especially oxygenated aromatics, are treated using the hydro-deoxygenation (HDO) process. Deoxygenation has seen the rise of effective transition metal-supported catalysts, both noble and non-noble, which have impeded the usage of traditional sulfided catalysts. Nevertheless, there are a number of reports in the literature of successful HDO processes using sulfided catalysts. As a model material for waste biomass, date pits were deoxygenated using 10 % Co–MoS2 produced via incipient wet impregnation in this study. The catalyst had a specific surface area of 15 m2/g, as proven by the nitrogen adsorption/desorption technique, the most essential analysis. Additionally, the catalyst was analyzed using XRD, SEM-EDX, HRTEM, and FTIR (for both the biomass deoxygenated products and the catalyst). The date pit pyrolysates were subjected to temperatures ranging from 100 to 500 °C in a 2-stage catalytic reactor for HDO. At 300 °C, 400 °C, and 500 °C, the condensable and non-condensable fractions could be identified. Deoxygenated aromatics were initially detected at 400 °C, with a complete conversion to benzene derivatives occurring at 500 °C, in contrast to the furanic products, which were primarily prevalent at 300 °C. At 18.12 % for the condensable fraction and 30.70 % for the non-condensable fraction, toluene had the highest relative area. Various oxygenated aromatic HDO reaction routes leading to toluene production were covered. The findings presented here opens the door to the potential widespread usage of Co–MoS2 in HDO processes with actual biomass fuels.
