Toluene thermodynamic properties

A column with partial condenser and reboiler is to be used for the separation of benzene (1) from toluene (2), giving a distillate with 0.95 mole fraction benzene and a bottoms product with 0.10 mole fraction benzene. The column will operate at 105 kPa pressure and a reflux ratio of 4. The feed, at 55°C and a flow rate of 100 kmol/h containing 45 mol% benzene and 55 mol% toluene, enters the column at the fifth theoretical stage from the top. The estimated average relative volatility (benzene relative to toluene) is assumed constant, and estimated at 2.41. Based on the column conditions and thermodynamic properties, the predicted q-value is 1.2. It is required to determine the number of theoretical stages below the feed to complete the separation. 

This definition gives values for a> of essentially zero for spherically symmetric molecules (e.g., the noble gases). Values of o) for 176 compounds are tabulated in Appendix I. For the species in Fig. 4.3, values of to are 0.00, 0.2415, 0,4869, and 0.6341, respectively, for methane, toluene, n-decane, and ethyl alcohol. Modification of the R-K equation by the addition of as a third constant greatly improves its ability to predict vapor pressures and other liquid-phase thermodynamic properties. 

Gaw, W. J. S win ton, F. L. Thermodynamic properties of binary systems containing hexafluorobenzene. Part 4. Excess Gibbs free energies of the three systems hexafluorobenzene -l- benzene, toluene, and p-xylene Trans. Faraday Soc. 1968,64,2023-2034... 

Nissema, A. Karvo, M. Thermodynamic properties of binary and ternary systems. Part V. Vapour pressures and thermodynamic excess functions of toluene + dimethyl sulphoxide mixtures Finn. Chem. Lett. 1977, (8), 222-226... 

Karvo, M. Thermodynamic properties of binary and ternary mixtures containing sulfolane. VI. Vapour-hquid equihbtia for (benzene + sulfolane) and (toluene + sulfolane) J. Chem. Thermodyn. 1980,12, 1175-1181... 

Fernandez, J. Garriga, R. Velasco, I. Otin, S. Thermodynamic properties of binary mixtures containing n-alkylamines I. Isothermal vapour-liquid equilibrium and excess molar enthalpy of n-aliylamine + toluene mixtures. Measurement and analysis in terms of group contributions Fluid Phase Equilib. 1998,152, 243-254... 

The two monomers of major interest, styrene and ethylene, are well known and details can be found on all aspects of their technology elsewhere. Poly(ethylene-co-styrene) is primarily produced via solution polymerization techniques using metallocene catalyst/co-catalyst systems, analogous to the production of copolymers of ethylene with a-olefin monomers. Solvents that can be employed include ethyl-benzene, toluene, cyclohexane, and mixed alkanes (such as ISO PAR E, available from Exxon). The thermodynamic properties of poly(ethylene-co-styrene), including solvent interactions and solubility parameter assessments, are important factors in relation to polymer manufacture and processing, and have been reported by Hamedi and co-workers (41). 

In 2015, Jorke and colleagues [31] calculated the thermodynamic properties and the resulting equilibrium composition of 1-decene in the presence of a Rh(BIPHEPHOS) catalyst at the temperature interval between 95 and 115 C in Ai M-dimethylformamide (DMF) or toluene, taking the network of all decene isomers into consideration (Scheme 5.5). 

Statistical Methods for Calculating Thermodynamic Functions Cable 5 Calculated and observed thermodynamic properties of toluene... 

Thermodynamic contributions from the internal rotation of several symmetric tops may be readily calculated by appropriate summation of terms in Table 4. Few reliable calculations, however, have been reported. Thermodynamic properties of propane and several methyl-substituted benzenes have been reported, for example, but subsequent more accurate work has shown the necessity for considering that the internal rotation may be restricted. " Although the subsequent calculations for m-xylene and p-xylene used 6-fold internal rotation barriers of 2.1 to 3.1 kJ mol", more recent statistical calculations for toluene employing the presence of free rotation suggest that internal rotation in the two xylenes may be effectively unrestricted. 

Murakami, S. Lam, V. T. Benson, G. C. The thermodynamic properties of binary aromatic systems. II. Excess enthalpies and volumes of benzene -t toluene and toluene -H isomeric xylene mixtures at 25.deg.C J. Chem. Thermodyn. 1969,1,397 7... 

Kokkonen, R Arvola, H. Thermodynamic properties of binary and ternary systems. Vapour-liquid equilibrium data in the triethylamine + toluene system. Thermochim. Acta 1984, 77, 333-339. 

The physical piopeities of toluene have been well studied expeiimentally. Several physical properties ate presented in Table 1 (1). Thermodynamic and transport properties can also be obtained, from other sources (2—7). The vapor pressure of toluene can be calculated as follows (8), where P is in kPa and T is in K. 

For the non-oxidative activation of light alkanes, the direct alkylation of toluene with ethane was chosen as an industrially relevant model reaction. The catalytic performance of ZSM-5 zeolites, which are good catalysts for this model reaction, was compared to the one of zeolite MCM-22, which is used in industry for the alkylation of aromatics with alkenes in the liquid phase. The catalytic experiments were carried out in a fixed-bed reactor and in a batch reactor. The results show that the shape-selective properties of zeolite ZSM-5 are more appropriate to favor the dehydroalkylation reaction, whereas on zeolite MCM-22 with its large cavities in the pore system and half-cavities on the external surface the thermodynamically favored side reaction with its large transition state, the disproportionation of toluene, prevails. 

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