Reactivity of CO2 during thermal cracking of heavy paraffins under supercritical conditions

Thermal cracking of n-hexadecane was investigated in a temperature range of 450-600 degrees C in the presence of CO2. Effects of pressure and temperature on product distribution were experimentally determined under both subcritical and supercritical conditions. At 1.2 MPa and with a CO2 to n-C-16 mole ratio of 25, C-6-C-14 olefins, C-10-C-17 paraffins, and C-5-C-10 fatty acids were identified in the liquid product. Experiments conducted at 4.5 MPa (supercritical) yielded higher selectivities for fatty acids and paraffins. The product distribution of fatty acids and olefins was found to be very sensitive to pressure and temperature. It was also concluded that heterogeneous carbon formation on the reactor surface was inhibited by the supercritical phase.


Borophosphates: Hydrothermal and microwave-assisted synthesis of Na-5[B2P3O13]
Hauf, C; Yılmaz, Ayşen; Kizilyalli, M; Kniep, R (Elsevier BV, 1998-10-01)
Na-5[B2P3O13] was first prepared by high temperature synthesis (T-max = 780 degrees C) and was characterized by X-ray single crystal investigations recently. We have now succeeded in the hydrothermal synthesis of the compound and obtained single-phase products at 150 degrees C after 1-2 days. A microwave-assisted synthesis takes only 2 min to transform a solid mixture of berate and phosphate hydrates into the crystalline title compound. Pure Na-5[B2P3O13] melts at 747 degrees C and solidifies during cooling...
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Ficicilar, Berker; Doğu, Timur (2006-06-30)
Carbon dioxide sorption rate parameters and sorption capacities on two different regenerable sorbents, namely hydrotalcite and activated trona, were investigated in a fixed bed flow adsorber, in the temperature range of 400-527 degrees C and 80-152 degrees C, respectively. Hydrotalcite, which was activated at 550 degrees C, was shown to give total and breakthrough CO2 sorption capacities as high as 1.16 and 0.70 mmol/g, respectively, at 452 degrees C, in the absence of water vapor. In the presence of excess...
Diffusion in Hypersonic Flows
Gür, Hilmi Berk; Eyi, Sinan (Nova Science Pub Inc, 2020-10-01)
In hypersonic flows, air goes into chemical reaction due to high temperature. Therefore, in addition to the Navier-Stokes Equations, chemical reaction equations need to be solved to analyze hypersonic flows. A model may be need to simulate the diffusion phenomena among chemical species. It is possible to implement Fick's Law of Diffusion as well as Stefan-Maxwell Diffusion Equation. Basically, in Fick's Law of Diffusion, the driving force is the species concentration differences. This method is similar to t...
Critical behaviour of ammonia near the melting point
Yurtseven, Hasan Hamit (2002-08-01)
This study gives our calculations for thermodynamic quantities, such as the isothermal cornpressibility k(T), thermal expansivity alphap and the specific heat C-P, as a function of temperature for solid ammonia near the melting point. Our calculations, which have been performed on the basis of an experimental study given in the literature, show that those thermodynamic quantities diver e near the melting point in ammonia. This is an indication that ammonia exhibits a critical transition as one approaches th...
DC conduction in electrochemically synthesized polypyrrole films
Kaynak, A (1998-01-01)
DC conductivity measurements were performed by modified four-probe rig on electrochemically synthesized polypyrrole films at a temperature range of -30 degrees C to 120 degrees C. Conductivity increased with temperature. The temperature dependence of conductivity was very high for lightly doped polymers, decreasing as the doping level increased. The model used to describe the conduction process was the conduction model originally developed for amorphous silicon by Mott and Davis. When applied to conducting ...
Citation Formats
G. Karakaş and T. Doğu, “Reactivity of CO2 during thermal cracking of heavy paraffins under supercritical conditions,” INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, pp. 4445–4451, 1997, Accessed: 00, 2020. [Online]. Available: