Cyclohexane, vapour pressure

At each cyclohexane vapour pressure level, the oxygen permeance through the open pores of the membrane was measured. 

Ewing, M.B., Sanchez Ochoa, J.C. (2000) The vapour pressure of cyclohexane over the whole fluid range determined using comparative ebulliometry. J. Chem. Thermodyn. 32, 1157-1167. 

Bawn, C. E. H. Patel, R. D., "High Polymer Solutions. Part 8. The Vapour Pressure of Solutions of Polyisobutene in Toluene and Cyclohexane," Trans. Faraday Soc., 52, 1664 (1956). 

The vapour pressure at 21 5° C. is 2 29 mm. of mercury. It is readily soluble in the organic solvents alcohol, ether, benzene, acetone, cyclohexane. It also dissolves in water (i gm. per 1,000 ml. of water), hydrolysis taking place. 

This technique, developed by Eyraud [140] modified by Katz et al. [143] and recently by Cuperus et al. [141], is based on the controlled blocking of pores by capillary condensation of a vapour (e.g. CCli, methanol, ethanol, cyclohexane), present as a component of a gas mixture, and the simultaneous measurement of the gas flux through the remaining open pores of the membrane. The capillary condensation process is related to the relative vapour pressure by the Kelvin equation. Thus for a cylindrical pore model and during desorption we have... 

Kaminishi, G.-L, Yokoyama, C., and Takahashi, S., 1987. Vapour pressures of binary mixtures of carbon dioxide with benzene, N-hexane and cyclohexane up to 7 MPa. Fluid Phase Eq., 34 83-99. 

The partial vapour pressures of mixtures of carbon tetrachloride and cyclohexane were measured by Scatchard, Wood, and Mochel (J. Amer. Chem. Soc. 1939, 61, 3206). They applied corrections to convert vapour pressures to fugacities and derived values for the excess Gibbs function G- by means of the formula... 

Doping can be achieved from the vapour phase (if the vapour pressure is sufficiently high), or in solution, chemically as well as electrochemically. In the latter case the polymer is one of the electrodes in an electrochemical cell and the process can be carefully controlled. The incorporation of solvent molecules is not considered in any of the diffraction studies, although it is sometimes stated that it may occur for smaller, polar molecules (e.g. for NH3, but not, say, in the case of cyclohexane). 

Inoue et al. [150] demonstrated that large amounts of carbon tetrachloride can be absorbed into 1-dimensional tunnels in copper(II) trans-1,4-cyclohexane dicarboxylate (Figure 14) under the saturated vapour pressure at room temperature, and the desorption can be performed easily by evacuation above room temperature. It was also confirmed that the absorption/desorption is reversible. The thermodynamic and structural properties were studied for the empty (non-absorbed) sample and partially-filled (10, 22 and 31% of the fiill carbon tetrachloride-absorbed) samples, using adiabatic calorimetry between 13 and 300 K and by powder XRD with high-energy synchrotron radiation. The heat- capacity anomaly due to the first-order phase transition observed in the empty sample was not observed in the fully-absorbed sample. However, the partially absorbed samples showed smaller heat-capacity anomalies at lower temperatures than the empty sample. Such phenomena were compared with the previous results for toluene-absorbed samples [151-153] and tfie differences were discussed. 

Column C. At the temperature assumed to be available with a normal industrial steam supply, a high solvent vapour pressure can be generated from a safe toluene/residue mixture. The pressure would be more than ample to allow for pressure drop through fractionating equipment and to condense at atmospheric pressure in this case. Cyclohexane is marginal in this respect but can probably just produce a residue mixture below LEL and be condensed without the use of vacuum in a low-pressure-drop plant. 

Ternary mixtures are known where the mixture has a higher vapour pressure than any of its components, for example ethyl alcohol, chloroform and hexane isopropyl alcohol, ethyl acetate, and cyclohexane. In all probability the number of components may be still greater but no actual observations appear to have been recorded. 

Martin, M. L. Youings, J. C. Vapour pressures and excess Gibbs free energies of cyclohexane -I- n-hexane, + n-heptane and n-octane at 298.150 KAust. J. Chem. 1980,33, 2133-2138... 

Jain, D. V. S. Yadav, O. P. Thermodynamics of n-alkane solutions Part III - Vapour pressure excess free eneigy for n-octtuie - cyclohexane system Indian J. Chem. 1971, 9,342-345... 

Thermodynamic properties of (n-alkoxyethanols + organic solvents). Xll. Tofed vapour pressure measurements for (n-hexane, n-heptane or cyclohexane -1- 2-methoxyethanol) at different temperatures J. Chem. Thermodyn. 2001,33,47-59... 

Nath, J. Dixit, A. P. Total vapour pressures for binary hquid mixtures of acetone with tetrachloroethylene, trichloroethylene, methylene chloride, 1,2-dichloroethane and cyclohexane at 273.15 K Fluid Phase Equilib. 1990,60, 205-212... 

Dahmani, A. Ait Kaci, A. Jose, J. Vapour pressures and excess functions of N,N,N ,N -tetramethylaIkanediamine + cyclohexane. A group contribution study of the N-N proximity effect Fluid Phase Equilib. 1997,130,271-279... 

The above equation relates directly the ratio of the weights of the two components present in the distillate of a mixture of two immiscible liquids to the molecular weights and vapour pressure of the two pure components. Examples of such pairs include water-cyclohexane, water-nitrobenzene, water-bromobenzene, water-aniline, etc.. 

A Nudepore membrane is characterised with perraporometry using cyclohexane as condensable vapour. At a relative pressure of 0.78 a high oxygen flux can be observed which does not increase further upon decreasing the relative vapour pressure. The t-layer of cyclohexane in the pore is 0.5 nm. The expraiment is performed at 34 C. 

The vapour pressures of pure liquid benzene and pure liquid cyclohexane at 40 are respectively 182.6 mmHg and 184.6 mmHg, and at this temperature they form an azeotrope containing 49.4 mole % benzene, and exerting a total pressure of 206.2 mmHg. 

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