Experimental Investigation of Coke Deposition in the Structure of Pd-Ag/α-Al2O3 Industrial Catalyst

Document Type : Research Article


1 Department of Chemical Engineering, Faculty of Chemical Engineering, Oil and Gas, Shiraz University, Shiraz, I.R. IRAN

2 Research and Development Department, Jam Petrochemical, Jam Energy Special Zone, Assalouye, I.R. IRAN


Coke formation is one of the most important reasons for the deactivation of petrochemical and refinery catalysts. This study investigates the coke formation in the structure of Pd-Ag/ α-Al2O3 catalyst. Various hydrocarbons as coke agents including xylene, toluene, benzene, propylene and green oil were investigated at different operating parameters including flow rate, temperature, pressure and coking time. The fresh and coked catalysts were investigated with FT-IR, FE-SEM and TGA methods. The obtained results revealed that this catalyst has a low tendency for the deposition of coke that could be according to the low surface acidity of it. In addition, the deposited coke in the case of green oil seems to be due to the cracking of heavy hydrocarbons in the pores of catalyst.


Main Subjects

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