Low-temperature oxidation reactions of crude oils using TGA-DSC techniques

Kök, Mustafa Verşan
Nurgaliev, Danis K.
In this research, combustion behaviour of three crude oils with different degrees API gravities was analysed. The thermogravimetric analyser (TGA) and differential scanning calorimeter (DSC) experiments were performed using three different heating rates (2, 5, and 10 degrees C min(-1)) under air atmosphere. The reaction regions, burn-out temperatures, and peak temperatures were determined accordingly. Two main reaction regions, particularly the low-temperature oxidation (LTO) and high-temperature oxidation (HTO) reactions, were figured out in TGA and DSC curves, which suggested exothermic behaviour. Kinetic parameters of the crude oils were determined using model free methods (Ozawa-Flynn-Wall, OFW, and Kissinger-Akahira-Sunose, KAS), which allows the calculation of kinetic properties at progressive conversion degrees without the requirement of any reaction models and f(alpha) estimations. The variation in activation energy with respect to the conversion degree pointed out that the LTO reaction stage can be subdivided into three subzones. The results indicated that the activation energies were changing depending on the conversion degree, which is an indication of complex reaction mechanisms. The change in activation energy with respect to conversion degree showed slight variation for heavy crude oil compared with that in light crude oil.


Comparative combustion kinetics for in situ combustion process
Kök, Mustafa Verşan (Elsevier BV, 2001-03-22)
In this research, thermal characteristics and combustion kinetics of three crude oils (13-27 degrees API) were investigated using DuPont 9900 thermal analysis system (TG/DTG). A sample size of 10 mg. heating rate of 10 degreesC min(-1) were used in the temperature range of 20-700 degreesC under air atmosphere. Theoretically, combustion of fuel can be initiated whenever oxygen comes in contact with fuel. However, the temperature, composition of fuel and oxygen supply dictates the nature of this reaction. In ...
Light crude oil combustion in the presence of limestone matrix
Kök, Mustafa Verşan; Keskin, C; Madarasz, J; Bagci, S (Springer Science and Business Media LLC, 2004-01-01)
In this study the combustion characteristics of crude oils (Karakus and Beykan) in the presence of a limestone matrix were determined using the thermogravimetry (TG/DTG). Experiments were performed at a heating rate of 10degreesC min(-1), whereas the air flow rate was kept constant at 10 L h(-1) in the temperature range of 20-900degreesC. In combustion with air, three distinct reaction regions were identified in all crude oil/limestone mixtures studied known as low temperature oxidation (LTO), fuel depositi...
Combustion reaction kinetics studies of Turkish crude oils
Bagci Suat, S.; Kök, Mustafa Verşan (2004-09-01)
In this research, sixteen experiments were conducted to study the combustion reaction kinetics of Turkish crude oils (Bati Raman, Camurlu, Raman, Adlyaman, Garzan, Karakus and Beykan) in a limestone medium. A mixture of the limestone and the crude oil was subjected to a controlled heating program under a constant flow rate of air. The produced gas was analyzed for its oxygen and carbon oxides contents. Although the molar CO2/CO ratios vary during low-temperature oxidation (LTO), for fuel deposition (FD) and...
Low temperature oxidation of carbon monoxide over alkali-metal promoted palladium-tin oxide catalysts
MİRKELAMOĞLU, Burcu; Karakaş, Gürkan (2005-09-17)
The CO oxidation activity of sol-gel prepared tin dioxide based palladium and sodium-palladium promoted catalysts were investigated by XRD, XPS, DRIFTS and temperature programmed desorption techniques. XPS data suggests that alkali-metal promotion results in the formation of super-oxide species and promotes the surface segregation of Pd atoms, increasing the number of active sites for CO adsorption/oxidation. The formation of a ternary oxide of sodium and palladium is Postulated. Through sub-ambient TPD exp...
Low-temperature thermoluminescence study of GaSe: Mn layered single crystals
Delice, S.; Hasanlı, Nızamı (Informa UK Limited, 2016-01-12)
Mangan doped GaSe single crystals have been studied by thermoluminescence measurements performed with various heating rates between 0.4 and 1.0 K/s in the temperature range of 10-300 K. Thermoluminescence spectra exhibited four distinguishable peaks having maximum temperatures at 47, 102, 139 and 191 K revealing the existence of trapping levels in the crystals. Curve fitting and initial rise methods were applied to observed peaks to determine the activation energies of four trapping levels. Capture cross-se...
Citation Formats
M. V. Kök and D. K. Nurgaliev, “Low-temperature oxidation reactions of crude oils using TGA-DSC techniques,” JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY, pp. 775–781, 2020, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/47736.