| dc.description.abstract | The present study investigates about the deactivation of catalyst during the fast pyrolysis of biomass. A mixture of spruce and pine was used as the feedstock. The simulations were carried out using COMSOL Multiphysics 5.3. The study aims to determine the behavior of deactivation on various operating parameters or conditions: different temperature (773, 823, and 873 K) and fluidizing gas velocity (0.4, 0.5, and 0.6 m/s). The mode of deactivation considered in this study was due to carbon deposition or fouling, blockage of the pore of the catalyst due to coke deposits on the surface of the catalyst that prevents the reactants to flow through its active sites, thus, decreasing the activity of the catalytic conversion process. The results showed that at high temperature the deactivation occurs rapidly for the porosity decreases the most at the said condition. Gas velocity greatly affects the time on stream of the species which also affects the deactivation of the catalyst as also mentioned by other researchers. The average porosity along the centerline of the catalyst bed at 0.4, 0.5, and 0.6 m/s is about 0.49, 0.483, and 0.498, respectively. Although, when the whole surface of the catalyst bed was considered, it is noticeable that the least gas velocity suffered from deactivation more than that of with high fluidizing gas velocity which means that the catalyst has the least carbon deposits on the catalyst bed. In conclusion, the catalyst gathered carbon deposits more at high temperature and at low fluidizing gas velocity and with that said, catalyst will deactivate further at this condition. Note that the value of the product should also be considered when performing catalytic biomass fast pyrolysis. | en_US |