A study on catalytic co-pyrolysis of cellulose with seaweeds polysaccharides over ZSM-5: Towards high-quality biofuel production

Abstract During pyrolysis process, hundreds of parallel and successive pyrolytic reactions between different constituents take place forming complex products. Understanding the pyrolysis behavior of each individual component as well as the interaction of different components is a challenge to further elucidate the complex biomass pyrolysis process. The present study aimed to explore the effect of celluloses (CE), as a main component of lignocellulosic biomass, on catalytic co-pyrolysis of Enteromorpha clathrata polysaccharides (ENP) and Sargassum fusiforme polysaccharides (SAP). The yields of bio-oil and non-condensable gas of pyrolyzed algal polysaccharides showed the lowest values, with the highest bio-char yield. However, co-pyrolysis of algal polysaccharides with CE enhanced the bio-oil yield of ENP and SAP by 34% and 29%, respectively, over the corresponding individual pyrolyzed polysaccharides. The results of GC–MS and FTIR of bio-oils confirmed the synergistic interaction between polysaccharides and CE during co-pyrolysis. Furthermore, bio-oils yields increased by 7.0% and 14.4% by catalytic co-pyrolysis of ENP + CE and SAP + CE, respectively. Interestingly, ZSM-5 resulted in significant reduction in acids and N-containing compounds of the produced bio-oil. In addition, ZSM-5 catalytic co-pyrolysis of the two studied polysaccharides with cellulose sharply increased furans and ketones proportions. The present results suggested catalytic co-pyrolysis as more favorable process for enhanced production of upgraded bio-oil.