Solubility Of Butane Research Articles

Using ethane and butane as probes to the molecular structure of 1-alkyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide ionic liquids

In this work, we have studied the solubility and the thermodynamic properties of solvation, between 298 and 343 K and at pressures close to atmospheric, of ethane and n-butane in several ionic liquids based on the bis[(trifluoromethyl) sulfonyl]imide anion and on 1-alkyl-3-methylimidazolium cations, [CnC1Im] [NTf2], with alkyl side-chains varying from two to ten carbon atoms. The solubility of butane is circa one order of magnitude larger than that of ethane with mole fractions as high as 0.15 in [C10C1Im][NTf2] at 300 K. The solubilities of both n-butane and ethane gases are higher for ionic liquids with longer alkyl chains. The behaviour encountered is explained by the preferential solvation of the gases in the non-polar domains of the solvents, the larger solubility of n-butane being attributed to the dispersive contributions to the interaction energy. The rise in solubility with increasing size of the alkyl-side chain is explained by a more favourable entropy of solvation in the ionic liquids with larger cations. These conclusions are corroborated by molecular dynamics simulation studies.

Prediction of solubility of gases in polystyrene by Adaptive Neuro-Fuzzy Inference System and Radial Basis Function Neural Network

Adaptive Neuro-Fuzzy Inference System (ANFIS) and Radial Basis Function Neural Network (RBF NN) have been developed for prediction of solubility of various gases in polystyrene. Solubility of butane, isobutene, carbon dioxide, 1,1,1,2-tetrafluoroethane (HFC-134a), 1-chloro-1,1-difluoroethane (HCFC-142b), 1,1-difluoroethane (HFC-l52a) and nitrogen in polystyrene is modeled by ANFIS and RBF NN in a wide range of pressure and temperature with high accuracy. The results obtained in this work indicate that ANFIS and RBF NN are effective methods for prediction of solubility of gases in polystyrene and have better accuracy and simplicity compared with the classical methods.

Solubility of butane and isobutane in molten polypropylene and polystyrene

AbstractThe solubility of butane and isobutane in molten polypropylene (PP) and polystyrene (PS) was measured at pressures up to 3 MPa and along four isotherms from 438 to 483 K for PP and from 348 to 473 K for PS. The solubility increased with increasing pressure and decreasing temperature. At 438 K and 2 MPa, the solubilities of butane and isobutane in PP were 0.15 and 0.11 g‐gas/g‐polym, respectively. At 423 K and 2 MPa, the solubilities of butane and isobutane in PS were 0.08 and 0.05 g‐gas/g‐polym, respectively. Solubility could be correlated with the Sanchez‐Lacombe equation of state with temperature‐dependent binary interaction parameters to within 4.4% average relative deviation. Henry's constant for these gases in the PP and PS obtained in this work were used to determine correlation equations along with literature data. Polym. Eng. Sci. 44:2083–2089, 2004. © 2004 Society of Plastics Engineers.

A phase separation caused by the solubility of butane in 2-methylpropan-2-ol–water mixtures

The solubility of butane and propane at a partial pressure of 101.3 kPa has been measured at 278–335 K in a solvent consisting of water and t-butyl alcohol (2-methylpropan-2-ol), of composition up to 0.08 mole fraction t-butyl alcohol. In the solvent, a phase separation occurs when butane gas dissolves into it at low temperatures, and over a wide composition range. Conditions for this separation have been identified and related to the high solubility of butane in the solvents at atmospheric pressure. The phenomenon is compared to conventional salting-out of non-electrolytes from water.

Evidence for adduct formation in the solubilisation of hydrophobic compounds by aqueous solutions of urea

The dependence on urea (U) concentration of the solubility of benzene (B) and of the neutral iron(II) complex cis-[Fe(o-phenanthroline)2(CN)2](I) in aqueous solutions at 25 °C has been studied by u.v.–visible spectrophotometry. The increase in solubility of (I) over the range 0–4 mol dm–3 urea corresponds to a single equilibrium constant β2=[IU2]/[I][U]2= 0.7 dm6 mol–2, while the increase in solubility of B over the range 0–6 mol dm–3 urea can be explained by the existence of two overlapping equilibria with constants K1=[BU]/[B][U]= 0.03 dm3 mol–1 and K2=[BU2]/[BU][U]= 0.3 dm3 mol–1. Evaluation of the published data of Wetlaufer et al.(J. Am. Chem. Soc., 1964, 86, 508) shows that the urea-dependent solubility of butane in water at 25 °C also corresponds to the existence of two analogous equilibria. The observation of equilibria with simple stoichiometries and with solute-dependent equilibrium constants indicates that urea exerts its solubilising effect directly through the formation of specific adducts with the solute and not indirectly by disrupting the structure of the solvent.

Solubility of butane in several polar and nonpolar solvents and in an acetone-butanol solvent solution

Solubllltles of butane are reported at 101.325 kPa and for temperatures ranging from 283.15 to 313.15 K In the nine solvents benzene, cyclohexane, methanol, ethanol, lpropanol, 1-butanol, acetone, methyl ethyl ketone, and aniline, and also in two-component, acetonel-butanol, mlxed solvent solutlons. The solublllty was determlned by utlllzing the Increase In mass resuitlng from the saturation of solvent with butane gas at constant temperature and pressure.

The solubility of hydrocarbon gases in lipid bilayers

The solubilities of 8 hydrocarbon gases in lipid bilayers have been determined at 25°C using a gas chromatographic technique. Results in 96% egg phosphatidylcholine, 4% phosphatidic acid bilayers expressed as Bunsen coefficients are: CH 4 0.20; C 2H 6 0.97; C 3H 8 3.6; n-C 4H 10 17; c-C 3H 4 11; i-C 4H 10 9.5; cis-butene 25; trans-butene 25. When 29 mol% cholesterol was incorporated with these phospholipids the Bunsen coefficient was reduced slightly. The observed solubilities are somewhat lower than those found in simple hydrocarbon solvents. The relative magnitudes of the solubilities of the gases in a given bilayer are closely related to the strength of their intermolecular forces. The solubility of butane was studied more extensively. No marked effects were observed when either surface charge or acyl chain saturation was increased, but the solubility in erythrocyte ghosts was much lower than that in lipid bilayers. The partition coefficient increased with decreasing temperature in egg lecithin and dimyristoylphosphatidylcholine. The entropy of solution in each case was more negative than that in isotropic non-polar solvents, and this accounts for the lower solubility in bilayers. The negative free energy of solution per CH 2 group for n-hydrocarbons is approximately twice that previously determined [11] for n-alcohols. This suggests that the concept of group contributions to solubility may not be universally applicable to lipid bilayers.

Solubility of butane in water and salt solutions at low temperatures

Solubility of butane in water and salt solutions at low temperatures