Kinetic analysis of ceria nanoparticle catalysed efficient biomass pyrolysis for obtaining high-quality bio-oil

Bio-oils obtained from biomass pyrolysis are being recognized as the next generation energy source. However, this technology has not yet been fully employed in real practice because of highly viscous and complex chemical nature of pyrolytic products and also due to lack of adequate understanding of such non-isothermal reactions. Catalysts can be used to upgrade the quality of bio-oils by enhancing the pyrolysis reaction efficiency and breaking down higher molecular weight compounds into simpler products. The study of the kinetics of this pyrolysis process explicates in depth knowledge about the reaction mechanism to have a better control over the efficiency of pyrolysis conversion of the biomass constituent. In this study, we focus on the kinetic analysis of ceria nanoparticles catalysed pyrolysis of cellulose, the major constituent of lignocellulosic biomass, for production of high-quality bio-oil. A non-isothermal kinetic analysis method identifies the reaction to be following a 'one and a half order' pathway and establishes significant lowering of activation energy after addition of the nanocatalyst. The merit of the nanocatalyst was again ascertained by performing qualitative analysis of pyrolytic liquids from cellulose in the presence of both bulk and nanosized ceria catalysts. It was observed that CeO2 nanoparticles improved the pyrolysis process enhancing the C-C bond scission reactions. As a result, percentage amount of lower molecular weight (96-144) compounds in the pyrolytic liquids increased with the addition of nanocatalyst (highest being 100% for 7% ceria nanocatalyst).