Experimental data and modeling of vapor-liquid equilibria of the ternary system carbon dioxide + water + methylamine at 313, 333 and 353 K and pressures up to 0.4 MPa

Vapour-liquid equilibrium in the carbon dioxide — p-cymene system at high pressure

Two- and three-phase equilibria in systems containing benzene derivatives, carbon dioxide, and water at 373.15 K and 10–30 MPa

Development and extension of PSRK/UNIQUAC model to methane and nitrogen gases

High pressure vapour-liquid equilibrium in the carbon dioxide — α-pinene system

The modeling of the solubility of water and carbon dioxide in silicate liquids (flash problem) is performed by assuming mechanical, thermal, and chemical equilibrium between the liquid magma and the gas phase. The liquid phase is treated as a mixture of ten silicate components + H2O or CO2, and the gas phase as a pure H2O or CO2. A general model for the solubility of a volatile component in a liquid is adopted. This requires the definition of a mixing equation for the excess Gibbs free energy of the liquid phase and an appropriate reference state for the dissolved volatile. To constrain the model parameters and identify the most appropriate form of the solubility equations for each dissolved volatile, a large number of experimental solubility determinations (640 for H2O and 263 for CO2) have been used. These determinations cover a large region of the P-T-composition space of interest. The resultant water and carbon dioxide solubility models differ in that the water model is regular and isometric, and the carbon dioxide model is regular and non-isometric. This difference is consistent with the different speciation modalities of the two volatiles in the silicate liquids, producing a composition-independent partial molar volume of dissolved water and a composition-dependent partial molar volume of dissolved carbon dioxide. The H2O solubility model may be applied to natural magmas of virtually any composition in the P-T range 0.1 MPa–1 GPa and > 1000 K, whereas the CO2 solubility model may be applied to several GPa pressures. The general consistency of the water solubility data and their relatively large number as compared to the calibrated model parameters (11) contrast with the large inconsistencies of the carbon dioxide solubility determinations and their low number with respect to the CO2 model parameters (22). As a result, most of the solubility data in the database are reproduced within 10% of approximation in the case of water, and 30% in the case of carbon dioxide. When compared with the experimental data, the H2O and CO2 solubility models correctly predict many features of the saturation surface in the P-T-composition space, including the change from retrograde to prograde H2O solubility in albitic liquids with increasing pressure, the so-called alkali effect, the increasing CO2 solubility with increasing degree of silica undersaturation, the Henrian behavior of CO2 in most silicate liquids up to about 30–50 MPa, and the proportionality between the fugacity in the gas phase, or the saturation activity in the liquid phase, and the square of the mole fraction of the dissolved volatile found in some unrelated silicate liquid compositions.

High-pressure density and vapor–liquid equilibrium for the binary systems carbon dioxide–ethanol, carbon dioxide–acetone and carbon dioxide–dichloromethane

Prediction of vapor-liquid and liquid-liquid equilibria in phenol + hydrocarbon systems

High pressure vapor–liquid equilibria in the ternary system orange peel oil (limonene)+ethanol+carbon dioxide

Vapor–liquid equilibrium of systems containing alcohols, water, carbon dioxide and hydrocarbons using SAFT

Vapor-liquid equilibria for binary mixtures of carbon dioxide with benzene, toluene and p-xylene

Vapour-liquid equilibrium and critical locus curve calculations with the soave equation for hydrocarbon systems with carbon dioxide and hydrogen sulphide

Phase equilibria and thermodynamic properties of molecular fluids from perturbation theory

Reaction of CO2 with [Mo(N2)2Ph2PCH2CH2PPh2] in PhMe at room temperature produces a material which analyses for [Mo(CO2)2(Ph2PCH2CH2PPh2)2], and which may be a bis(carbon dioxide) complex. The recent description(1) of a CO2 complex of molybdenum, namely [Mo(CO2)2(PMe3)4], prompts us to report a homologous compound [Mo(CO2)2(Ph2PCH2CH2PPh2)2], which we isolated from the reaction of CO2 and [Mo(N2)2(Ph2PCH2CH2PPh2)2] at room temperature under tungsten-filament irradiation. The similar reaction in PhMe at reflux produces [Mo(CO)2(Ph2PCH2CH2PPh2)2](2). The yellow crystalline compound was isolated as a THF solvate inca. 75% yield and is air-stable. The i.r. spectrum contains a strong band in the 1695–1710 cm−1 region, associated with the CO2, which compares with the 1670 cm−1 band reported(1) for [Mo(CO2)2(PMe3)4] and a band at 1760 cm−1 found for [Mo(CO2)2(PMe2Ph)4](3). The diamagnetic compound has not yet provided crystals suitable for x-ray analysis. Consequently, we were not able to determine whether this is a genuine CO2 complex or whether the two CO2 molecules have combined head-to-tail, as found for [Ir(C2O4)Cl(PMe3)3](4). The31P {1H} n.m.r. spectrum shows a pair of asymmetric doublets centred atca. 108 and 78 p.p.m. downfield from (MeO)3P. This suggests that the phosphoruses are no longer equivalent. The13C {1H n.m.r. spectrum has a broad resonance at 27.1 p.p.m. downfield from TMS, which may arise from the bound CO2 in whatever form it may be. Reactions with acids and oxidising agents did not give conclusive results. Thus treatment with Br2 (4 moles) in C6H6 yields CO (1 mole) and CO2 (1 mole); H2SO4 and HCl in C6H6 produced CO2 (1 mole), as does neat CCl4. The most convincing experiment was the reaction with MeNC, which was carried out in THF under reflux in a closed system. Two moles of CO2 were evolved, and the complex product was the known material(5) [Mo(CNMe)2(Ph2PCH2CH2PPh2)2], formed in quantitative yield. We think that this material is probably a bis(carbon dioxide) complex, its stability arising from the lack of dissociation of the two diphosphine ligands, but we cannot exclude the possibility of head-to-tail ring(4). We observed no reactions with CO, H2, MeBr or P(O2CH2)3CMe, but Ph2PCH2CH2PPh2 in C6H6 under reflux produces CO2 (1 mole). Carbon dioxide in THF under irradiation reacts only slowly with [W(N2)2(PMe2Ph)4] and [W(N2)2(Ph2PCH2PPh2)2]; no products have been identified.

A new ebulliometric technique. Vapour-liquid equilibria in the binary systems ethanol- n-heptane and ethanol- n-nonane

Noncovalent interactions in 18 weakly bound binary complexes formed between either of the two end-on orientations of the CO molecule and the methylated carbon positive σ-hole associated with the hydrophobic part of the CH3-X molecules are exploited using the density functional theory to examine the physical chemistry of the recently introduced 'carbon bonds' (Phys. Chem. Chem. Phys., 2013, 15, 14377), where X = -NO2, -CN, -F, -Cl, -Br, -OH, -CF3, -CCl3, and -NH2. The two important types of interactions are identified as C···O and C···C, the latter has probably never studied before, and are found to be stabilized by charge-transfer delocalizations between the electron-acceptor and -donor natural bond orbitals of the interacting partners involved, unveiled using natural bond orbital analysis. Application of atoms in molecular theory revealed preferable quantum mechanical exchange-correlation energy channels and (3, -1) bond critical points (bcps) between the atoms of noncovalently bonded pairs in these complexes, in excellent agreement with the results of the noncovalent-interaction reduced-density-gradient (NCI-RDG) theory that revealed expected isosurfaces and troughs in the low density region of the RDG vs. sign(λ2)ρ plots. The dependencies of the C···O and C···C bcp charge densities on their corresponding local energy densities, as well as on their corresponding bond electron delocalization indices are found to exhibit nontrivial roles of these topological descriptors to explain the stabilities of the investigated binary complexes. Moreover, the vibrational red- and blue-shifts in the CO bond stretching frequencies, and concomitant elongations and contractions of the corresponding bond lengths, both with respect to the monomer values, are observed upon the formation of the C···O- and C···C-bonded complexes, respectively. The increase and decrease in the complex dipole moments, relative to the sum of their respective monomer values, are found to be a characteristic that separates the aforementioned red- and blue-shifted interactions. In analogy with dihydrogen bonding, as well as that with the charge and electrostatic surface potential model descriptions, we suggest the C···C interactions to be referred to as dicarbon bonds.