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The objective of this study is to assess the storage of acid gas, containing CO2 and H2S, in a depleted naturally fractured reservoir (NFR) using single matrix block (SMB) approach. The acid gas dissolution in oil is considered by Peng‐Robinson equation of state and compositional simulation. The PHREEQC package is used to determine acid gas solubility in formation brine. Three types of acid gases with different compositions are used for this study and their swelling behavior and miscibility in relation to the reservoir oil are analyzed. An SMB model, with a matrix block surrounded by fractures, is constructed, and validated for simulation of a real experiment. The simulation is conducted for synthetic and real reservoir fluids when the oil is in its residual saturation. A sensitivity analysis is performed to study the effects of key parameters, such as acid gas composition, reservoir pressure, permeability, porosity and matrix height on the storage capacity and oil recovery factor. The matrix has a volume of 27 m3 and about half of acid gas storage is achieved in the first 5 years while the simulations are run for 30 years. The results show that up to 90% of remained oil is recoverable, and more than 0.67 kmol of acid gas per cubic meter of matrix is stored whether matrix contains a real oil or a synthetic one. Higher storage is achieved for higher matrix porosities and heights and large H2S proportion in acid gas. In all cases about 10% of acid gas is trapped in water and the remaining 90% is dissolved in oil. The mineral trapping was more active in CO2‐rich acid gases. While about 10 kg of the matrix rock was dissolved in the acidic brine when the acid gas contained H2S, the amount of the dissolved minerals in acidic brine resulted from the injection of CO2‐rich acid gas was more than 16 kg. Finally, this study gives a comparative analysis of the storage performance of acid gas mixture and pure CO2. © 2024 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This study explored diethanolammonium chloride ([DEA]Cl) as a potential ionic liquid from low‐cost and commercial ones for gas separation. There are three kinds of functional sites in [DEA]Cl: acidic NH2+, hydrogen‐bond OH, and nucleophilic Cl−. The separation of NH3/N2/H2, SO2/CO2/N2, and H2S/CO2/CH4 was considered, because the three mixtures are extensively involved in many industrial processes. The experimental results demonstrated that [DEA]Cl exhibited excellent ability to separate the mixture of NH3/N2/H2. The [DEA]Cl also exhibited the proper capacity to separate SO2/CO2/N2, but the capacity of [DEA]Cl for the separation of H2S/CO2/CH4 was inferior. The theoretical calculations revealed that NH2+ and OH worked synergistically to contribute to the ability of [DEA]Cl for excellent separation of NH3 from NH3/N2/H2, with Cl− contributing to the proper separation of SO2 from SO2/CO2/N2. This study provides experimental and theoretical basis for the industrial application of [DEA]Cl in the area of gas separation. [ABSTRACT FROM AUTHOR]

Methods for predicting Henry's law constants Hij are important as experimental data are scarce. We introduce a new machine learning approach for such predictions: matrix completion methods (MCMs) and demonstrate its applicability using a data base that contains experimental Hij values for 101 solutes i and 247 solvents j at 298 K. Data on Hij are only available for 2661 systems i + j. These Hij are stored in a 101 × 247 matrix; the task of the MCM is to predict the missing entries. First, an entirely data‐driven MCM is presented. Its predictive performance, evaluated using leave‐one‐out analysis, is similar to that of the Predictive Soave‐Redlich‐Kwong equation‐of‐state (PSRK‐EoS), which, however, cannot be applied to all studied systems. Furthermore, a hybrid of MCM and PSRK‐EoS is developed in a Bayesian framework, which yields an unprecedented performance for the prediction of Hij of the studied data set. [ABSTRACT FROM AUTHOR]

The catalytic activity of metal nanoparticles (NPs) supported on porous supports can be controlled by various factors, such as NPs size, shape, or dispersivity, as well as their interaction with the support or the properties of the support material itself. However, these intrinsic properties are not solely responsible for the catalytic behavior of the overall reaction system, as the local environment and surface coverage of the catalyst with reactants, products, intermediates and other invloved species often play a crucial role in catalytic processes as well. Their contribution can be particularly critical in liquid‐phase reactions with gaseous reactants that often suffer from low solubiltiy. One example is D‐glucose oxidation with molecular oxygen over gold nanoparticles supported on porous carbons. The possibility to promote oxygen delivery in such aqueous phase oxidation reactions via the immobilization of heterogenous catalysts onto the interface of perfluorocarbon emulsion droplets is reported here. Gold‐on‐carbon catalyst particles can stabilize perfluorocarbon droplets in the aqueous phase and the local concentration of the oxidant in the surroundings of the gold nanoparticles accelerates the rate‐limiting step of the reaction. Consequently, the reaction rate of a system with the optimal volume fraction of fluorocarbon is higher than a reference emulsion system without fluorocarbon, and the effect is observed even without additional oxygen supply. [ABSTRACT FROM AUTHOR]

We present a new strategy to estimate the temperature‐dependent vapor–liquid equilibria and solvation free energies of dilute neutral molecules based on only their estimated solvation energy and enthalpy at 298 K. These two pieces of information coupled with matching conditions between the functional forms developed by Japas and Levelt Sengers for near critical conditions and by Harvey for low and moderate temperature conditions allow the fitting of a piecewise function that predicts the temperature‐dependent solvation energy for dilute solutes up to the critical temperature of the solvent. If the Abraham and Mintz parameters for the solvent and solute are available or can be estimated from group contributions, this method requires no experimental data and can still provide accurate estimates with an error of about 1.6 kJ/mol. This strategy, which requires minimal computational resources, is shown to compare well with other methods of temperature‐dependent solvation free energy prediction. [ABSTRACT FROM AUTHOR]

We describe a field study where tracer gas was injected into a subsurface cavity created by a small chemical explosion beneath the water table. The main objective of the study is to compare the migration of sulfur hexafluoride (SF6) and xenon (Xe) through an explosion‐generated fracture network and to study the influence of ground water on gas transport. A mixture of tracer gases (50% of SF6 and 50% of Xe) was injected on 31 October 2018 and gas sampling continued until 8 November 2018. We observe similar trends in SF6 and Xe concentrations at four ground surface sampling sites. The changes in the SF6/Xe ratios with time show that more SF6 than Xe is observed during the barometric pressure lows when the absolute measured concentrations are highest. Conversely, the ratio SF6/Xe is less than 1 during the high‐pressure intervals when absolute measured concentrations are low. The results of the experiment suggest that during barometric pressure lows the tracer is migrating to the surface primarily by advective gas phase transport, whereas during barometric pressure highs, advection is suppressed and near‐surface evaporation of interstitial pore fluid with tracer dissolved in it becomes more important. Thus, the results of the experiment show that the gas concentrations at the surface are controlled by the combined effects of the gas dissolution into pore water and the barometric pressure fluctuations. Plain Language Summary: We injected a mixture of two tracer gases (Xe and SF6) into an underground explosion‐generated cavity and monitored their concentrations at the surface. The arrival times at the surface were similar for both gases. The observed ratios of SF6 and Xe concentrations typically varied by about a factor of 2 over a million‐fold range of measured concentrations and correlate with the absolute gas concentrations. Our results indicate that the breakthrough times and the concentrations of the tracer gases are affected by fluctuations of the barometric pressure. Key Points: We conducted a unique field‐scale experiment to compare the migration of two tracer gases, SF6 and Xe, through fracture networks, generated by chemical explosionsThe observed arrival times were similar for both gases; SF6 concentrations usually tracked Xe concentrations within a factor of 2 over concentration variations of 6 orders of magnitudeThe observed surface concentrations are affected by the fluctuations in the atmospheric pressure and by gas solubilities in pore water [ABSTRACT FROM AUTHOR]

A popular and desirable function of superhydrophobic coatings is their remarkable ability to retain an entrapped layer of air, called a plastron, when submerged underwater. The drawback is that the air layer is short‐lived due to solvation into the surrounding liquid. While manipulating the solubility of gases using temperature is a possible approach, it generally requires inefficiently heating large volumes of water. Following the demonstrated ability to maintain air bubbles on superhydrophobic surfaces for drag reduction, this article introduces a novel method of extracting gas from water to replenish and stabilize the plastron on superhydrophobic surfaces for sustained antifouling abilities. This method involves locally heating the liquid surrounding a superhydrophobic coating, reducing gas solubility, and causing the gas to nucleate at the liquid–air interface. The approach requires a relatively low energy input, due to the small volume of locally heated water. With a constant supply of equilibrated water and minimal energy input, the plastron can survive indefinitely without the need for a mechanical delivery of air. The thermoregenerating superhydrophobic samples were shown to exhibit excellent antifouling behavior and inhibited diatom attachment over a period of 5 days. [ABSTRACT FROM AUTHOR]

Liquid Organic Hydrogen Carrier (LOHC) systems have attracted growing attention in recent years as efficient way to store and transport hydrogen in the existing infrastructures for liquid fuels. This contribution highlights the additional feature that hydrogenation of the LOHC compound dibenzyltoluene with technical relevant H2/CO2 gas mixtures (up to 30 % CO2) gives access to hydrogen purification and hydrogen storage in one single process step. Alumina supported Rh and Pd catalysts proved to be especially suitable for this task. The rhodium catalysts enabled efficient aromatics hydrogenation in the temperature range of 120 °C to 150 °C with moderate methane formation (CH4/CO2<0.1 at 150 °C). The palladium catalyst showed the lowest selectivity to methane formation (CH4/CO2<0.1 at 270 °C) and promising hydrogenation activity at temperatures above 200 °C even in the presence of CO and CO2. Separation and storage! The hydrogenation of the LOHC compound dibenzyltoluene with technical relevant H2/CO2 gas mixtures (up to 30 % CO2) gives access to hydrogen purification and hydrogen storage in one single process step. Rh and Pd catalysts supported on alumina are especially suitable for this task showing high selectivity for aromatics hydrogenation over CO2 hydrogenation. [ABSTRACT FROM AUTHOR]

Abstract: To gain insight into the influence of metal–organic framework (MOF) fillers and polymers on membrane performance, eight different composites were studied by combining four MOFs and two polymers. MOF materials (NH2‐MIL‐53(Al), MIL‐69(Al), MIL‐96(Al) and ZIF‐94) with various chemical functionalities, topologies, and dimensionalities of porosity were employed as fillers, and two typical polymers with different permeability‐selectivity properties (6FDA‐DAM and Pebax) were selected as matrices. The best‐performing MOF–polymer composites were prepared by loading 25 wt % of MIL‐96(Al) as filler, which improved the permeability and selectivity of 6FDA‐DAM to 32 and 10 %, while for Pebax they were enhanced to 25 and 18 %, respectively. The observed differences in membrane performance in the separation of CO2 from N2 are explained on the basis of gas solubility, diffusivity properties, and compatibility between the filler and polymer phases. [ABSTRACT FROM AUTHOR]

Abstract: The solubility of propylene, ethylene, and propylene–ethylene mixtures in isotactic polypropylene (iPP) is measured with a high‐pressure sorption balance at different temperatures and pressures. The obtained sorption isotherms of both binary systems (propylene–iPP and ethylene–iPP) are fitted with the Sanchez–Lacombe equation of state. It is found that both binary interaction parameters for ethylene and propylene in iPP decrease with temperature. At temperatures above 70 °C, the overall solubility of ethylene plus propylene mixtures can be modeled using purely binary systems. However, at temperatures under 70 °C it is necessary to use a ternary solubility model that accounts for interactions between the penetrants and the polymer. Furthermore, at lower temperatures, the total solubility of the gas mixture is higher than the sum of gas solubilities of individual components because the anti‐solvent effect of ethylene (on propylene) is weaker than the co‐solvent effect of propylene on ethylene. Moreover, the molar ratio of ethylene to propylene dissolved in iPP increases with temperature and pressure. Desorption studies show that the effective diffusion coefficient increases with pressure and temperature and that the effective diffusivity of gaseous ethylene–propylene mixtures is lower than that of either of the individual gases. [ABSTRACT FROM AUTHOR]

A novel approach using a semipermeable Teflon AF-2400 tube-in-tube membrane contactor was developed for the measurement of gas solubility in organic solvents. This membrane ensures gas saturation of liquids in continuous flow at a specific pressure and temperature. After liquid decompression, the amount of gas outgassed was measured with a bubble meter and used for solubility calculation. The proposed method was applied to the measurement of oxygen solubility in toluene and benzyl alcohol. Validation experiments were initially performed by comparing the obtained oxygen solubility in toluene with literature data. With higher temperature, the solubility of oxygen in benzyl alcohol was found to increase, indicating that the oxygen-dissolving process is endothermic. Finally, an empirical correlation of Henry's law constant as a function of temperature was determined. [ABSTRACT FROM AUTHOR]

In this Perspective, we provide a detailed discussion of the techniques and methods used for determining the solubility of gases in ionic liquids (ILs). This includes various experimental measurement techniques, equation of state (EOS) modeling, and predictive molecular-based modeling. Many of the key papers from the past 15 years are discussed and put into the context of the latest advances in the field. Limitations of these methods plus future developments and new research opportunities are discussed. © 2017 American Institute of Chemical Engineers AIChE J, 2017 [ABSTRACT FROM AUTHOR]

Solvent effects on the reaction equilibrium of the 1-dodecene hydroformylation in a decane/N,N-dimethylformamide solvent system is investigated. The reaction was performed at different decane/N,N-dimethylformamide ratios and at temperatures between 368 K and 388 K. The equilibrium concentrations of all reactants and products were determined experimentally. The enthalpy and Gibbs energy of this reaction at the ideal-gas standard state were determined by quantum-chemical calculations in good agreement with literature data. Moreover, quantum-chemically calculated standard Gibbs energies of reaction at infinite dilution in liquid decane/DMF-solvent mixtures allowed a qualitative prediction of the solvent effect on the equilibrium concentrations. Based on the standard Gibbs energy of reaction at the ideal-gas standard state and on fugacity coefficients calculated using the Perturbed-Chain Statistical Associating Fluid Theory, the equilibrium concentrations of reactants and products for the 1-dodecene hydroformylation performed in decane/N,N-dimethylformamide mixtures of different compositions could be predicted in very good agreement with experimental data. © 2017 American Institute of Chemical Engineers AIChE J, 63: 4576-4585, 2017 [ABSTRACT FROM AUTHOR]

In this work, aqueous 1-allyl-3-methylimidazolium formate ([Amim][HCOO]) was studied as a potential sorbent for CO2 separation. The density and viscosity of aqueous [Amim][HCOO] were measured at temperatures ranging from 293.15 to 333.15 K at atmospheric pressure. The solubility of CO2 and CH4 in dry [Amim][HCOO] as well as the CO2 solubility in aqueous [Amim][HCOO] were measured at pressures up to 1.8 MPa and temperatures of 298.2, 313.2, and 333.2 K. The results showed that the density and viscosity of aqueous [Amim][HCOO] as well as the CO2 solubility in aqueous [Amim][HCOO] decreased upon increasing the water concentration and temperature. The viscosity was very sensitive to the water concentration. The experimental density and viscosity of aqueous [Amim][HCOO] were fitted to semiempirical equations, and the excess molar volume and viscosity deviations were calculated to investigate the interaction between the [Amim][HCOO] ionic liquid and water. The experimental vapor-liquid equilibrium was represented with the nonrandom two-liquid and Redlich-Kwong model. The model parameters can be further implemented into Aspen Plus software to conduct process simulations. [ABSTRACT FROM AUTHOR]

A modified version of a standard device for measuring gas adsorption and desorption isotherms and surface area of adsorbents and catalysts (ASAP (Accelerated Surface Area and Porosimetry System) 2020, Micromeritics USA) is used for the first time to measure gas solubilities (i.e., CO2) in low vapor pressure liquids (i.e., the IUPAC standard ionic liquid 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C6mim][Tf2N])) in the Henry's law region. The solubility data are in very good agreement with the reported data in literature. Furthermore, the Henry's law constants are calculated from the solubility data and compared to the experimental data found in literature. The results from this study demonstrate that Micromeritics ASAP 2020 is a suitable apparatus for gas absorption by solvents with reduced vapor pressures. © 2017 American Institute of Chemical Engineers AIChE J, 63: 2981-2986, 2017 [ABSTRACT FROM AUTHOR]

This article presents the design and construction of a new isochoric saturation apparatus for the determination of gas solubility in liquids based on the gas drop pressure method. The major improvement of this design is the separation between the solubility and the gas cells. With this separation, the change of pressure and temperature inside the system is minimum when the gas gets in contact with the liquid and it allows degassing the liquid in an easy way. The performance of the equipment was evaluated measuring the solubility of argon and nitrogen in pure water at 283.15, 288.15, 293.15, and 298.15 K. The gas solubility was calculated according to the Henry's law. The results obtained and the comparison with literature values show that the equipment provides an accurate and precise method for determination of gas solubility in water. © 2017 American Institute of Chemical Engineers AIChE J, 63: 3105-3109, 2017 [ABSTRACT FROM AUTHOR]

Significance The gas solubility in 1-dodecyl-3-methylimidazolium [C12MIM] based ionic liquids (ILs) was measured at temperatures (333.2, 353.2, and 373.2) K and pressures up to 60 bar for the first time. The popular UNIFAC-Lei model was successfully extended to long-chain imidazolium-based IL and gas (CO2, CO, and H2) systems. The free volume theory was used to explain the gas solubility and selectivity in imidazolium-based ILs by calculating the fractional free volume and free volume by the COSMO-RS model. Furthermore, the excess enthalpy of gas-IL system was concerned to provide new insights into temperature dependency of gas (CO2, CO, and H2) solubility in ILs. The experimental data, calculation, and theoretical analysis presented in this work are important in gas separations with ILs or supported ionic liquid membranes. © 2017 American Institute of Chemical Engineers AIChE J, 63: 1792-1798, 2017 [ABSTRACT FROM AUTHOR]

Choline chloride + phenylacetic acid-based deep eutectic solvents are studied. Their most relevant experimental physicochemical properties at different mixing ratios together with the CO2 solubility data obtained in wide pressure and temperature ranges are reported. The presented materials exhibit a significant CO2 capture performance with low corrosion effect when compared with the most common amine-based CO2 capture agents. Detailed rheological measurements are carried out and various models are applied to describe the dynamic flow behavior of the solvents. The CO2 absorption mechanism is evaluated by studying the behavior of the liquid gas and interface. Due to the advantages of low cost, nontoxicity, and favorable physical properties, these solvents are an environmentally promising alternative for effective CO2 capture technological applications. [ABSTRACT FROM AUTHOR]

ABSTRACT A systematic strategy to molecularly design flexible tough hydrolyzed polymers of intrinsic microporosity (hPIM-1) films from the PIM-1 polymer is explored in this study. Flexible films can be fabricated from N-methyl-2-pyrrolidone (NMP) by appropriate hydrolysis conditions. The optimal weight ratio of NaOH/H2O/EtOH in the base-catalyzed reaction is 0.5/2/2. Because of the highly polar carboxylic acid groups, the resultant hPIM-1 has a lower water contact angle. The hPIM-1 has one-half fractional free volume compared to PIM-1 which is in good agreement with permeability. Moreover, hPIM-1 follows as the same dual-mode sorption model as PIM-1. To the best of our knowledge, this is the first ever reported flexible hPIM-1 film in the literature. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 344-354 [ABSTRACT FROM AUTHOR]

Artificial neural networks (ANN) are used to correlate and predict the solubility of air gases (oxygen, nitrogen, and argon) in saline solutions. Several network architectures were considered in the study and correlated and predicted values of solubility were compared with values obtained from the literature. The model is general in the sense that just one model can correlate and predict the solubility of any of the three gases. As a measure of the accuracy of the method, the average relative deviation, the average relative absolute deviation, and the maximum relative absolute deviation are evaluated. The ANN model obtained give lower deviations than analytical models presented in the literature. The chosen ANN model give absolute deviations lower than 1% with some few exceptions and maximum relative absolute deviations are always below 6%. [ABSTRACT FROM AUTHOR]

The article presents abstracts on environmental topics which include the solubility of air gases in saline solutions for mining processes, concentration and hysteresis behavior of dissolved oxygen in rivers, and the enhanced activity of immobilized horseradish peroxidase for phenols removal.

The solubility of commercially available natural gas in commercially available diesel fuel at room temperature and defined pressure is investigated experimentally. The gas phase is considered to be pure methane. The use of Henry's law to model the solubility is discussed. Solubility is given in terms of the mole fraction and the volumetric mass concentration of dissolved gas and the corresponding Henry's coefficients. The solubility is compared to that of pure methane in pure hexadecane, which is similar to diesel fuel with respect to the mean carbon number. [ABSTRACT FROM AUTHOR]

Soluble gas stabilisation ( SGS) is a recently proposed method to extend the shelf life of food. However, no studies have determined the amount of carbon dioxide absorbed in food and particularly in oysters. Thus, the aim of this study was to determine CO2 absorption and desorption rates in oysters during the solubilisation process. Cooked oysters were placed in the apparatus's chamber, CO2 was injected into the chamber, and the SGS process started at different pressures, temperatures and gas/product (g/p) ratios. CO2 absorption and desorption rates were obtained from data of CO2 concentration in the chamber headspace and calculated by mathematical models. The results showed higher absorption rates under higher pressure, higher g/p ratio and lower temperature (0 °C). The concentration of CO2 dissolved in the oysters was 21008.45 mg CO2 kg product−1. On the other hand, lower desorption rates occurred for the lowest pressure (200 kPa) and lowest gas/product ratio (1:1). For CO2 desorption from oysters, it was observed that 10 min was enough to desorb a large amount of CO2 under normal atmosphere. [ABSTRACT FROM AUTHOR]

The gas solubility of pure oxygen and of pure carbon dioxide as well as of their gaseous mixture are measured in the ternary liquid mixture cyclohexane + cyclohexanone + cyclohexanol at 313.6 K with a high-pressure view-cell technique using the synthetic method. The new experimental data are used to assess the capability of molecular simulation and conductor-like screening model (COSMO)-SAC to predict multicomponent fluid-phase coexistence behavior. These methods are also compared systematically on the basis of experimental binary fluid-phase coexistence data. In that comparison also the Peng-Robinson (PR) equation of state is included as a reference. Molecular simulation and COSMO-SAC yield good results and are found to be far superior to the PR equation of state both in predictive and in adjusted mode. © 2013 American Institute of Chemical Engineers AIChE J, 59: 2236-2250, 2013 [ABSTRACT FROM AUTHOR]

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Cover illustration. A molecular‐level view of the gas absorption process in which an ionic liquid is used to separate carbon dioxide from methane. Image courtesy: Kristina Davis, University of Notre Dame Center for Research Computing. 10.1002/aic.15957 [ABSTRACT FROM AUTHOR]

Review: 49 refs. [ABSTRACT FROM AUTHOR]