PETR 127 |
| Thermodynamic equilibrium calculations are performed at 298 to 1000 K and 1 bar for a mixture of 46 compounds obtained from hydrocracking of decalin with an assumption that the reaction mixture behaves as an ideal gas. The quantum chemical method, G3MP2, is used to calculate the standard free energy change of formation for compounds for which the thermochemical data are not available in the open literature. Thermochemical properties of individual reactions show that the endocyclic cracking reactions of naphthenes differ from acyclic and exocyclic cracking reactions by negative standard entropy change of reaction. The ratios of equilibrium constants for individual endocyclic cracking reactions over exocyclic and acyclic cracking reactions increase with increasing temperatures. The equilibrium calculations reveal that the selectivity of ring opening products of decalin can be maximized by favoring the formation of unsaturated compounds at higher operating temperatures. Experimental results from hydrocracking of decalin on a Pt-Ir/HY zeolite catalyst along with the thermodynamic predictions suggest that higher operating temperatures will help maximizing the selectivity of ring opening products. |
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Chemistry of Petroleum and Emerging Technologies
9:00 AM-12:00 PM, Thursday, August 23, 2007 Boston Park Plaza -- White Hill Rm, Oral
Division of Petroleum Chemistry |