Kinetic analysis of the termal decomposition of colombian vacuum residua by termogravimetry

Abstract

Five different Colombian vacuum residues were thermally decomposed in a thermogravimetric analyzer. Three heating rates were employed to heat the sample up to 650 °C. The kinetic analysis was performed by the Coats-Redfern method to describe the non-isothermal pyrolysis of the residua. A reaction model where the reaction order gradually increases from first to second order is proposed, resulting on an excellent agreement of the experimental with the calculated data. The results also indicate that the pyrolysis of a vacuum residue cannot be modeled by a single reaction mechanism.Keywords: TGA, pyrolysis, distillables, coke, coking, asphaltenes. RESUMENCinco fondos de vacío colombianos fueron procesados mediante descomposición térmica en una balanza termogravimétrica. Tres tasas de calentamiento fueron empleadas para calentar la muestra hasta una temperatura de 650 °C. El análisis cinético fue realizado mediante el método de Coats-Redfern para describir la pirólisis no isotérmica del residuo, se propuso un modelo de reacción donde el orden de la reacción aumenta gradualmente de primer a segundo orden y se encontró un excelente ajuste de los datos calculados con los datos experimentales. Los resultados también indican que la pirólisis de un fondo de vacío no puede ser modelada por un solo mecanismo de reacción.

Two-Step Thermal Cracking of an Extra-Heavy Fuel Oil: Experimental Evaluation, Characterization, and Kinetics

“…Until now, several studies have been reported on the thermal processing of heavy hydrocarbons, , their chemistry, , their kinetics, ,− and their economies . Depending upon the type of the desirable products of a thermal cracking process, different reaction conditions are employed.…”