DTA derived kinetics of Jordan oil shale

Effect of demineralization and heating rate on the pyrolysis kinetics of Jordanian oil shales

“…It increases from 70 kJ/mol at 1°C/min to 83 kJ/mol at 50°C/min. These values are in close agreement with those reported by Khraisha [39] (73-77 kJ/mol at about 4°C/min) and by Haddadin and Tarawneh [42] (79.6 kJ/mol at 100°C/min), who used oil shale samples from the same locality of the samples used in the current work. Skala et al [14] also observed that activation energy increased with the increase of heating rate (103, 113 and 117 kJ/mol at 2, 5, and 10°C/min, respectively).…”

CO2 supercritical fluid extraction of Jordanian oil shale utilizing different co-solvents

“…The values of activation energies obtained for the unextracted oil shale is similar to the results obtained by others [27,28]. It can be observed that the activation energy, which is the amount of energy required for the system to process the reaction, is higher for the SCF extracted samples.…”

Kinetics and Structural Evolution During Aging of Coker Vapor Deposits

“…However, the NMR spectra of aged deposits (both 2-day and 24-day) only exhibit aromatic peak centered at 128 ppm. It should be noted that the integral intensity of 24-day aged deposits is much weaker than that of 2-day-aged deposits (7.86 × 10 7 vs. 16.02 × 10 7 ) and close to that of industrial sample B (9.04 × 10 7 ), which indicates that there is more NMR-invisible graphite in the 24-day-aged deposits. Sample D exhibits more NMR-invisible graphitic structures (integral intensity 9.29 × 10 5 ).…”

“…This model was developed for relatively low volatile content materials and processes such as coal pyrolysis [9,[15][16][17]. For the laboratory fresh deposits collected at low temperatures (<500 • C), kinetic description is made possible by a two-stage model, a first-stage kinetic model of low activation energy barrier and low preexponential factor, and a second stage of higher activation energy and preexponential factor.…”