Effect of asphaltenes on pyrolysis kinetics of saturates

Abstract

The pyrolysis reaction kinetics of saturates and the effect of asphaltenes on kinetics of saturates were investigated. Residues obtained from two Turkish crudes (Yenikoy asphaltic crude oil and Luleburgaz crude oil) were fractionated into saturates, aromatics, resins and asphaltenes using the SARA technique. The samples were characterized by elemental analysis and proton NMR. The pyrolysis reactions were carried out at 400, 450 and 500 degrees C for reaction times ranging from 30 to 300 min in batch tubing reactors. Saturates, coke and asphaltenes product fractions were recovered by using a solvent extraction sequence. The variations of products yields were used to calculate the reaction rate constants and the activation energies for neat saturates and saturates-asphaltenes mixture pyrolysis. The reactivity of saturates was strongly affected by the presence of asphaltenes in the reaction environment. Experimental results provided insight into heavy oil pyrolysis reaction kinetics and coke formation. (C) 2000 Elsevier Science B.V. All rights reserved.