OMAR SALIM AL-AYED, MOHAMMAD WALEED AMER, MOHAMMED MATOUQ
The oil shale (OS) sample from Sultani mine, southern Jordan, was subjected to thermogravimetric/differential thermogravimetric (TG/DTG) and differential scanning calorimetry (DSC) analysis. Analysis was used to determine the kinetic parameters in the 300–540 °C temperature range, employing different heating rates (3, 5, 10, 20, 30 °C/min). The first order conversion function was found to best represent the oil shale pyrolysis kinetics. The data in the studied pyrolysis temperature range was divided into three zones according to the behavior of the quantity ln(dx/dT/(1–x)) vs 1/T(K). In the first linear zone, the apparent activation energy and frequency factor were found to be in the range of 63.1–94.2 kJ/mol and 9.3E+3–5.03E+6, respectively. In the second zone of analysis, the apparent activation energy was found to be negative and varied between –25.8 and –2.13 kJ/mol and the corresponding frequency factor was in the range of 19.65–0.00098. In the third zone under study, the calculated apparent activation energy and frequency factors were in the range of 186.9–342.1 kJ/mol and 1.87E+12–1.46E+23, respectively.
Keywordsoil shale pyrolysis, activation energy, kinetic parameters, differential thermogravimetric analysis.