Pereira-Almao, PedroCarss, Andrew2014-09-242014-11-172014-09-242014http://hdl.handle.net/11023/1809This thesis investigates the recycling and deactivation of molybdenum sulfide ultra-dispersed catalyst in VGO. An Ultra Dispersed Catalyst Recycling Pilot Plant capable of continuously recycling catalyst was modified and used to carry out this work. A theoretical model to predict catalyst deactivation with time after catalyst cutoff to the plant under recycling operation was developed. The experimental concentration of catalyst followed the decline in catalyst concentration predicted by the theoretical calculation. The effect of operating conditions including space-time, recycle ratio and reaction temperature were investigated and found consistent with results in literature. Under recycle mode of operation, the quality of the hot separator bottoms material was followed with time after catalyst cutoff. As the catalyst concentration declined, the MCR conversion declined disproportionally slower than the catalyst concentration. After three passes through the reactor, the catalyst activity was at or above the activity of fresh catalyst, and thus, did not deactivate.engUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.Engineering--ChemicalCatalysisCatalystHydroprocessingDeactivationUltra-DispersedRecycleMolybdenummaster thesis10.11575/PRISM/28542