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Sharma KV, Alloush RM, Salim O, Piri M. Phase behavior of n-hexane confined in unconsolidated nanoporous media: an experimental investigation at varying pore sizes and temperatures. Phys Chem Chem Phys 2024; 26:18162-18172. [PMID: 38896490 DOI: 10.1039/d4cp00936c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
We investigated the effect of confinement on the phase behavior of hexane in nanopores of mesoporous silica at varying pore diameters and temperatures using a patented gravimetric apparatus. The adsorption and desorption isotherms were experimentally measured, and the capillary condensation and evaporation pressures were calculated from the isotherms. The results show that, for all pore sizes and temperatures utilized here, the confinement of fluids significantly lowers the vapor-liquid phase transition pressures. However, its evaporation, i.e., liquid-vapor phase transition, occurs at a lower pressure than its capillary condensation counterpart. The experimental findings demonstrate that the confinement effect becomes weaker in wider nanopores due to the reduced solid-fluid interactions in larger spaces. Furthermore, it is evident from isotherms that hexane rapidly approaches a supercritical-like state at high temperatures when confined in smaller pores, resulting in an ambiguous vapor-liquid phase transition. In contrast, this behavior disappears in larger pores at similar temperatures. Moreover, the present study compares the fully gravimetric adsorption method against the thermogravimetric approach. The results show that the fully gravimetric method, which directly measures the mass of the adsorbed or condensed fluids, provides significant advantages over the thermogravimetric counterpart. The findings of this study are expected to be of fundamental interest to a wide range of science and engineering communities concerned about the behavior of heavier hydrocarbons in various industrial applications, and modeling the confined phase behavior of fluids and developing robust equations of state (EOS).
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Affiliation(s)
- Keerti Vardhan Sharma
- Center of Innovation for Flow through Porous Media Department of Energy and Petroleum Engineering, University of Wyoming Laramie, Wyoming 82071, USA.
| | - Rami M Alloush
- Center of Innovation for Flow through Porous Media Department of Energy and Petroleum Engineering, University of Wyoming Laramie, Wyoming 82071, USA.
| | - Omer Salim
- Center of Innovation for Flow through Porous Media Department of Energy and Petroleum Engineering, University of Wyoming Laramie, Wyoming 82071, USA.
| | - Mohammad Piri
- Center of Innovation for Flow through Porous Media Department of Energy and Petroleum Engineering, University of Wyoming Laramie, Wyoming 82071, USA.
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2
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Roosta A, Zendehboudi S, Rezaei N. Improving the estimation accuracy of confined vapor-liquid equilibria by fine-tuning the pure component parameter in the PC-SAFT equation of state. Phys Chem Chem Phys 2024; 26:13790-13803. [PMID: 38655721 DOI: 10.1039/d3cp05979k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
We propose a thermodynamic model that combines the Young-Laplace equation and perturbed chain-statistical associating fluid theory (PC-SAFT) equation of state to estimate capillary condensation pressure in microporous and mesoporous sorbents. We adjust the PC-SAFT dispersion-energy parameter when the pore size becomes comparable to the molecular dimension. This modelling framework is applied to diverse systems containing associating and non-associating gases, various sorbents, and a wide range of temperatures. Our simulation results show that under extreme confinement, a higher value of the dispersion-energy parameter (ε) is required. Furthermore, using the experimental saturation pressure data for 18 different associating and non-associating confined fluids, we find that the shift in the PC-SAFT dispersion energy correlates with the ratio of the sorbent mean pore size to the PC-SAFT segment size (rp/σ). By fitting to the capillary condensation data, the relative deviation between the confined and bulk PC-SAFT dispersion energy parameter is only 0.1% at rp/σ = 15; however, this deviation starts to increase exponentially as rp/σ decreases. For a sorbent with large pores, when rp/σ > 15, the capillary condensation pressure results from our model are similar to the predictions from the Kelvin equation. Using a dataset containing 235 saturation pressure data points composed of 18 pure gases and 4 binary mixtures, the overall AARD% from our model is 12.26%, which verifies the good accuracy of our model. Because the mean sorbent pore radius (rp), the PC-SAFT energy parameter (ε), and segment size (σ) are known a priori, our model estimates the corrected energy parameter for small pores and, thus, extends its applicability.
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Affiliation(s)
- Aliakbar Roosta
- Department of Separation Science, School of Engineering Science, LUT University, Lappeenranta, Finland.
| | - Sohrab Zendehboudi
- Department of Process Engineering, Memorial University, St. John's, NL, Canada
| | - Nima Rezaei
- Department of Separation Science, School of Engineering Science, LUT University, Lappeenranta, Finland.
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3
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Trzeciak K, Wielgus E, Kaźmierski S, Khalaji M, Dudek MK, Potrzebowski MJ. Unexpected Factors Affecting the Kinetics of Guest Molecule Release from Investigation of Binary Chemical Systems Trapped in a Single Void of Mesoporous Silica Particles. Chemphyschem 2022; 24:e202200884. [PMID: 36507917 DOI: 10.1002/cphc.202200884] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 12/09/2022] [Accepted: 12/09/2022] [Indexed: 12/15/2022]
Abstract
In this work, we present results for loading of well-defined binary systems (cocrystal, solid solution) and untreated materials (physical mixtures) into the voids of MCM-41 mesoporous silica particles employing three different filling methods. The applied techniques belong to the group of "wet methods" (diffusion supported loading - DiSupLo) and "solvent-free methods" (mechanical ball-mill loading - MeLo, thermal solvent free - TSF). As probes for testing the guest1-guest2 interactions inside the MCM-41 pores we employed the benzoic acid (BA), perfluorobenzoic acid (PFBA), and 4-fluorobenzoic acid (4-FBA). The guests intermolecular contacts and phase changes were monitored employing magic angle spinning (MAS) NMR Spectroscopy techniques and powder X-ray diffraction (PXRD). Since mesoporous silica materials are commonly used in drug delivery system research, special attention has been paid to factors affecting guest release kinetics. It has been proven that not only the content and composition of binary systems, but also the loading technique have a strong impact on the rate of guests release. Innovative methods of visualizing differences in release kinetics are presented.
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Affiliation(s)
- Katarzyna Trzeciak
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza Łódź, 112, 90-363, Lodz, Poland
| | - Ewelina Wielgus
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza Łódź, 112, 90-363, Lodz, Poland
| | - Sławomir Kaźmierski
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza Łódź, 112, 90-363, Lodz, Poland
| | - Mehrnaz Khalaji
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza Łódź, 112, 90-363, Lodz, Poland
| | - Marta K Dudek
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza Łódź, 112, 90-363, Lodz, Poland
| | - Marek J Potrzebowski
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza Łódź, 112, 90-363, Lodz, Poland
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4
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Yu C, Zhao J, Wang Z, Guo P, Liu H, Su Z, Liao H. Vapor-liquid phase equilibrium of n-pentane in quartz nanopores by grand canonical Monte Carlo calculation. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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5
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Adidharma H, Tan SP. Experiments of Vapor–Liquid Phase Transition of Fluids Confined in Nanopores: Implications on Modeling. Ind Eng Chem Res 2022. [DOI: 10.1021/acs.iecr.2c01514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hertanto Adidharma
- Department of Petroleum Engineering, University of Wyoming, Laramie, Wyoming 82071, United States
- Department of Chemical Engineering, University of Wyoming, Laramie, Wyoming 82071, United States
| | - Sugata P. Tan
- Planetary Science Institute, Tucson, Arizona 85719, United States
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6
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Morishige K. Revisiting the Nature of Adsorption and Desorption Branches: Temperature Dependence of Adsorption Hysteresis in Ordered Mesoporous Silica. ACS OMEGA 2021; 6:15964-15974. [PMID: 34179641 PMCID: PMC8223431 DOI: 10.1021/acsomega.1c01643] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 05/28/2021] [Indexed: 06/13/2023]
Abstract
To gain a deeper understanding as to the nature of the adsorption hysteresis due to capillary condensation of nitrogen in ordered mesoporous silicas, we calculated the temperature dependences of the activated condensation, equilibrium transition, and activated desorption pressures for nitrogen in spherical and cylindrical silica pores with several different pore sizes on the basis of semimacroscopic continuum models. The results clearly indicate that the models capture the exact nature of capillary condensation and evaporation phenomena of a fluid in cagelike and cylindrical mesopores. The temperature dependences of the adsorption hysteresis of nitrogen measured confirm previous theoretical predictions for cylindrical pores: for the ordered mesoporous silicas with cylindrical mesopores at least greater than ∼7 nm in diameter, the capillary condensation takes place via a nucleation process followed by a growth process of a bridging meniscus at pressures higher than the equilibrium transition, while the capillary evaporation takes place via a receding meniscus from pore ends at the equilibrium. For SBA-15 and MCM-41 with smaller mesopore sizes, on the other hand, the capillary condensation takes place close to the equilibrium transition pressures, while the capillary evaporation takes place at pressures lower than the equilibrium, owing to single pore blocking due to corrugation of the cylindrical pores. We discuss the effect of curvature on surface tension in capillary condensation, as well as the relation between a change in the mechanisms of adsorption and desorption and the pore corrugation in the cylindrical pores.
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Affiliation(s)
- Kunimitsu Morishige
- Department of Chemistry, Okayama University of Science, 1-1 Rida-cho, Kita-ku, Okayama 700-0005, Japan
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7
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Herz-Thyhsen RJ, Miller QRS, Rother G, Kaszuba JP, Ashley TC, Littrell KC. Nanoscale Interfacial Smoothing and Dissolution during Unconventional Reservoir Stimulation: Implications for Hydrocarbon Mobilization and Transport. ACS APPLIED MATERIALS & INTERFACES 2021; 13:15811-15819. [PMID: 33769780 DOI: 10.1021/acsami.0c22524] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Hydraulic fracturing of low-permeability rocks significantly enhances hydrocarbon production from unconventional reservoirs. However, fluid transport through low-permeability rocks and the influence of geochemical transformations on pore networks are poorly constrained. Mineral reactivity during interactions with injected water may alter the physical nature of the rock, which may affect hydrocarbon mobility. To assess alterations to the rock, we have previously conducted a hydrothermal experiment that reacted cubed rock samples (1 cm3) with synthetic hydraulic fracturing fluid (HFF) to simulate physicochemical reactivity during hydraulic fracturing. Here, we analyze unreacted and reacted rocks by small-angle neutron scattering and high-pressure mercury intrusion to determine how the pore networks of unconventional reservoir rocks are influenced by the reaction with hydraulic fracturing injectates. Our results suggest that fluid-rock interactions exhibit a two-fold influence on hydrocarbon recovery, promoting both hydrocarbon mobilization and transport. Pore-matrix interfaces smooth via the removal of clay mineral surface asperities, reducing the available surface area for hydrocarbon adsorption by 12-75%. Additionally, HFF-induced dissolution creates new pores with diameters ranging from 800-1400 nm, increasing the permeability of the rocks by a factor of 5-10. These two consequences of mineral dissolution likely act in concert to release hydrocarbons from the host rock and facilitate transport through the rock during unconventional reservoir production.
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Affiliation(s)
- Ryan J Herz-Thyhsen
- Department of Geology and Geophysics, University of Wyoming, Laramie, Wyoming 82071, United States
| | - Quin R S Miller
- Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
| | - Gernot Rother
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6110, United States
| | - John P Kaszuba
- Department of Geology and Geophysics, University of Wyoming, Laramie, Wyoming 82071, United States
- School of Energy Resources, University of Wyoming, Laramie, Wyoming 82071, United States
| | - Thomas C Ashley
- Department of Geology and Geophysics, University of Wyoming, Laramie, Wyoming 82071, United States
| | - Kenneth C Littrell
- Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6393, United States
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8
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Xiong W, Zhao YL, Qin JH, Huang SL, Zhang LH. Phase equilibrium modeling for confined fluids in nanopores using an association equation of state. J Supercrit Fluids 2021. [DOI: 10.1016/j.supflu.2020.105118] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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9
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Mohagheghian E, Hassanzadeh H, Chen Z. Evaluation of Shale-Gas-Phase Behavior under Nanoconfinement in Multimechanistic Flow. Ind Eng Chem Res 2020. [DOI: 10.1021/acs.iecr.0c02615] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Erfan Mohagheghian
- Department of Chemical & Petroleum Engineering, Schulich School of Engineering, University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - Hassan Hassanzadeh
- Department of Chemical & Petroleum Engineering, Schulich School of Engineering, University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - Zhangxin Chen
- Department of Chemical & Petroleum Engineering, Schulich School of Engineering, University of Calgary, Calgary, Alberta T2N 1N4, Canada
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10
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Rezlerová E, Brennan JK, Lísal M. Methane and carbon dioxide in
dual‐porosity
organic matter: Molecular simulations of adsorption and diffusion. AIChE J 2020. [DOI: 10.1002/aic.16655] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Eliška Rezlerová
- Department of Molecular and Mesoscopic Modelling, The Czech Academy of Sciences Institute of Chemical Process Fundamentals Prague Czech Republic
- Department of Physics, Faculty of Science J. E. Purkinje University Ústí n. Lab Czech Republic
| | - John K. Brennan
- Weapons and Materials Research Directorate U.S. Army Combat Capabilities Development Command Army Research Laboratory Aberdeen Proving Ground Maryland USA
| | - Martin Lísal
- Department of Molecular and Mesoscopic Modelling, The Czech Academy of Sciences Institute of Chemical Process Fundamentals Prague Czech Republic
- Department of Physics, Faculty of Science J. E. Purkinje University Ústí n. Lab Czech Republic
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11
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Sun H, Li H. Phase-Behavior Modeling of Hydrocarbon Fluids in Nanopores Using PR-EOS Coupled with a Modified Young-Laplace Equation. ACS OMEGA 2020; 5:15177-15191. [PMID: 32637791 PMCID: PMC7331056 DOI: 10.1021/acsomega.0c00963] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Accepted: 06/10/2020] [Indexed: 06/11/2023]
Abstract
The effect of capillary pressure on the vapor-liquid two-phase equilibrium calculation has been extensively studied for the past two decades. However, the calculation accuracy is often weakened by the false assumptions and inherent flaws present in the modeling process. In this work, a modified Young-Laplace equation proposed by Tan and Piri [Tan, S.; Piri, M. Equation-of-State Modeling of Confined-Fluid Phase Equilibria in Nanopores. Fluid Phase Equilibr. 2015, 393, 48-63.] is coupled with volume-translated Peng-Robinson equation of state to study the effect of capillary pressure on the two-phase equilibrium calculation in confined nanopores. In order to successfully apply the modified Young-Laplace equation during the vapor-liquid equilibrium calculation process, this study models the tuning parameter λ in the modified Young-Laplace equation (as proposed by Tan and Piri for perturbed-chain statistical associating fluid theory equation of state) for several pure hydrocarbons and their mixtures by matching experimental data collected from the literature. The tuning parameter λ can be expressed as a unique function for each pure substance or mixture. It is found that the tuning parameter λ shows a quadratic polynomial relationship with temperature, and the value of λ is always less than one. The λ can become negative under certain circumstances, which adjusts the capillary pressure to a lower value. It increases with an increasing pore radius; this is different from the results obtained by Tan and Piri which showed that the tuning parameter λ decreases with an increasing pore radius. The above rules apply to the tuning parameter λ obtained for both pure substances and mixtures. Using the two-phase equilibrium calculation coupled with the modified Young-Laplace equation, the calculated vapor pressures for pure substances and two-phase boundaries for mixtures match very well with the experimental data. Implementation of the modified Young-Laplace equation greatly improves the accuracy of the two-phase equilibrium calculation considering the capillarity effect. Such a modeling strategy could be integrated into a reservoir simulator to conduct more accurate flow simulations for tight/shale reservoirs.
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12
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13
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Tan SP, Barsotti E, Piri M. Criticality of Confined Fluids Based on the Tensile Strength of Liquids. Ind Eng Chem Res 2020. [DOI: 10.1021/acs.iecr.0c01848] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Sugata P. Tan
- Center of Innovation for Flow through Porous Media, Department of Petroleum Engineering, University of Wyoming, 1000 E. University Avenue, Laramie, Wyoming 82071, United States
| | - Elizabeth Barsotti
- Center of Innovation for Flow through Porous Media, Department of Petroleum Engineering, University of Wyoming, 1000 E. University Avenue, Laramie, Wyoming 82071, United States
| | - Mohammad Piri
- Center of Innovation for Flow through Porous Media, Department of Petroleum Engineering, University of Wyoming, 1000 E. University Avenue, Laramie, Wyoming 82071, United States
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14
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Maximov MA, Galukhin AV, Gor GY. Pore-Size Distribution of Silica Colloidal Crystals from Nitrogen Adsorption Isotherms. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:14975-14982. [PMID: 31633940 DOI: 10.1021/acs.langmuir.9b02252] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Silica colloidal crystals are face-centered cubic structures comprised of silica spheres with the diameters ranging between tens and hundreds of nanometers. The voids between the spheres form pores, which can be probed by nitrogen adsorption porosimetry. Here, we prepared two mesoporous samples and a macroporous reference sample and then measured nitrogen adsorption and desorption isotherms for further characterization. We proposed a straightforward procedure for calculation of the pore-size distribution of silica colloidal crystals from nitrogen adsorption isotherms. The procedure is based on the adsorption integral equation solution with a kernel of theoretical isotherms, consistent with the procedure used for many other porous materials. The solution is carried out using the non-negative least squares (NNLS) regression with Tikhonov regularization. The kernel of mesoporous isotherms is built on the basis of the macroscopic Derjaguin-Broekhoff-de Boer (DBdB) theory of capillary condensation considering the voids as a network of spheres. Application of our procedure for the analysis of the adsorption branches of experimental isotherms resulted in bimodal distributions, where the modes matched well with the sizes of the voids in the colloidal crystals face centered cubic structure: the main mode corresponds to the octahedral voids and the second mode to the tetrahedral voids. Furthermore, we modified the surface of the samples with organics and repeated the characterization procedure for the modified samples. The resulting pore-size distribution for the samples with the modified surface matched the original one quite closely. It demonstrates the procedure as a simple and efficient technique to estimate the pore-size distribution and justifies the spherical shape approximation for the voids in the silica colloidal crystals.
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Affiliation(s)
- Max A Maximov
- Otto H. York Department of Chemical and Materials Engineering , New Jersey Institute of Technology , 323 Dr. Martin Luther King Jr. Blvd , Newark , New Jersey 07102 , United States
| | - Andrey V Galukhin
- Alexander Butlerov Institute of Chemistry , Kazan Federal University , Kremlevskaya Str. 18 , 420008 Kazan , Russian Federation
| | - Gennady Y Gor
- Otto H. York Department of Chemical and Materials Engineering , New Jersey Institute of Technology , 323 Dr. Martin Luther King Jr. Blvd , Newark , New Jersey 07102 , United States
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15
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Lowry E, Piri M. Effect of Surface Chemistry on Confined Phase Behavior in Nanoporous Media: An Experimental and Molecular Modeling Study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:9349-9358. [PMID: 30008204 DOI: 10.1021/acs.langmuir.8b00986] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
It is well accepted that nanopore size is a controlling parameter in determining the phase behavior of confined adsorbate molecules. Despite this knowledge, the quantitative effect of surface chemistry on the confined phase behavior is a factor that remains obfuscated. Obtaining a complete understanding of the variables controlling confined phase behavior is a critical step in developing more complete equations of state for predictive modeling. To this end, a combined experimental and molecular modeling study was conducted to investigate the effects of surface chemistry and wetting on the confined phase behavior of propane and n-butane in modified and unmodified silica MCM-41. Isotherms were measured in four types of silica MCM-41 modified with varying sizes of alkyl groups to determine the effects of increasing surface modification. Results showed that increased pore surface coverage of carbon resulted in a notable change in the capillary condensation pressures, adsorption enthalpy, and confined critical temperature of the adsorbate. Correlations between the surface coverage of carbon and the confined critical temperature were presented and supported by thermodynamic arguments. The primary conclusions were partially supported by hybrid molecular dynamics-Monte Carlo simulations of propane adsorption in models of the four types of experimental adsorbents. Several differences were noted and explained between the experimental and modeling results. Energetic heterogeneity on the surface of the modified MCM-41 adsorbents as well as differences in adsorbate entropy induced by surface features and chemistry were suggested as primary driving factors for the observed trends. The results of this work have direct implications for improving understanding of confined phase behavior in materials of varying surface chemistries.
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Affiliation(s)
- Evan Lowry
- College of Engineering and Applied Sciences , University of Wyoming , Laramie , Wyoming 82071 , United States
| | - Mohammad Piri
- College of Engineering and Applied Sciences , University of Wyoming , Laramie , Wyoming 82071 , United States
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16
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Barsotti E, Saraji S, Tan SP, Piri M. Capillary Condensation of Binary and Ternary Mixtures of n-Pentane-Isopentane-CO 2 in Nanopores: An Experimental Study on the Effects of Composition and Equilibrium. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:1967-1980. [PMID: 29360363 DOI: 10.1021/acs.langmuir.7b04134] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Confinement in nanopores can significantly impact the chemical and physical behavior of fluids. While some quantitative understanding is available for how pure fluids behave in nanopores, there is little such insight for mixtures. This study aims to shed light on how nanoporosity impacts the phase behavior and composition of confined mixtures through comparison of the effects of static and dynamic equilibrium on experimentally measured isotherms and chromatographic analysis of the experimental fluids. To this end, a novel gravimetric apparatus is introduced and validated. Unlike apparatuses that have been previously used to study the confinement-induced phase behavior of fluids, this apparatus employs a gravimetric technique capable of discerning phase transitions in a wide variety of nanoporous media under both static and dynamic conditions. The apparatus was successfully validated against data in the literature for pure carbon dioxide and n-pentane. Then, isotherms were generated for binary mixtures of carbon dioxide and n-pentane using static and flow-through methods. Finally, two ternary mixtures of carbon dioxide, n-pentane, and isopentane were measured using the static method. While the equilibrium time was found important for determination of confined phase transitions, flow rate in the dynamic method was not found to affect the confined phase behavior. For all measurements, the results indicate qualitative transferability of the bulk phase behavior to the confined fluid.
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Affiliation(s)
- Elizabeth Barsotti
- Department of Petroleum Engineering, University of Wyoming , Laramie, Wyoming 82071, United States
| | - Soheil Saraji
- Department of Petroleum Engineering, University of Wyoming , Laramie, Wyoming 82071, United States
| | - Sugata P Tan
- Department of Petroleum Engineering, University of Wyoming , Laramie, Wyoming 82071, United States
| | - Mohammad Piri
- Department of Petroleum Engineering, University of Wyoming , Laramie, Wyoming 82071, United States
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17
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Alcohols react with MCM-41 at room temperature and chemically modify mesoporous silica. Sci Rep 2017; 7:9960. [PMID: 28855555 PMCID: PMC5577207 DOI: 10.1038/s41598-017-10090-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 08/03/2017] [Indexed: 11/12/2022] Open
Abstract
Mesoporous silica has received much attention due to its well-defined structural order, high surface area, and tunable pore diameter. To successfully employ mesoporous silica for nanotechnology applications it is important to consider how it is influenced by solvent molecules due to the fact that most preparation procedures involve treatment in various solvents. In the present work we contribute to this important topic with new results on how MCM-41 is affected by a simple treatment in alcohol at room temperature. The effects of alcohol treatment are characterized by TGA, FTIR, and sorption calorimetry. The results are clear and show that treatment of MCM-41 in methanol, ethanol, propanol, butanol, pentanol, or octanol at room temperature introduces alkoxy groups that are covalently bound to the silica surface. It is shown that alcohol treated MCM-41 becomes more hydrophobic and that this effect is sequentially more prominent going from methanol to octanol. Chemical formation of alkoxy groups onto MCM-41 occurs both for calcined and hydroxylated MCM-41 and the alkoxy groups are hydrolytically unstable and can be replaced by silanol groups after exposure to water. The results are highly relevant for mesoporous silica applications that involve contact or treatment in protic solvents, which is very common.
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18
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Gus’kov VY, Sukhareva DA, Salikhova GR, Karpov SI, Kudasheva FK, Roessner F, Borodina EV. Thermodynamic characteristics of the adsorption of organic molecules on modified МCM-41 adsorbents. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2017. [DOI: 10.1134/s0036024417070135] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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19
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Echeverría JC, Calleja I, Moriones P, Garrido JJ. Fiber optic sensors based on hybrid phenyl-silica xerogel films to detect n-hexane: determination of the isosteric enthalpy of adsorption. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2017; 8:475-484. [PMID: 28326238 PMCID: PMC5331324 DOI: 10.3762/bjnano.8.51] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 01/24/2017] [Indexed: 05/31/2023]
Abstract
We investigated the response of three fiber optic sensing elements prepared at pH 10 from phenyltriethoxysilane (PhTEOS) and tetraethylsilane (TEOS) mixtures with 30, 40, and 50% PhTEOS in the silicon precursor mixture. The sensing elements are referred to as Ph30, Ph40 and Ph50, respectively. The films were synthesized by the sol-gel method and affixed to the end of optical fibers by the dip-coating technique. Fourier transform infrared spectroscopy, N2 adsorption-desorption at 77 K and X-ray diffraction analysis were used to characterize the xerogels. At a given pressure of n-hexane, the response of each sensing element decreased with temperature, indicating an exothermic process that confirmed the role of adsorption in the overall performance of the sensing elements. The isosteric adsorption enthalpies were obtained from the calibration curves at different temperatures. The magnitude of the isosteric enthalpy of n-hexane increased with the relative response and reached a plateau that stabilized at approximately -31 kJ mol-1 for Ph40 and Ph50 and at approximately -37 kJ mol-1 for Ph30. This indicates that the adsorbate-adsorbent interaction was dominant at lower relative pressure and condensation of the adsorbate on the mesopores was dominant at higher relative pressure.
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Affiliation(s)
- Jesús C Echeverría
- Institute for Advanced Materials – Universidad Pública de Navarra, Campus Arrosadía, 31006 Pamplona, Spain
- Department of Applied Chemistry – Universidad Pública de Navarra, Campus Arrosadía, 31006 Pamplona, Spain
| | - Ignacio Calleja
- Institute for Advanced Materials – Universidad Pública de Navarra, Campus Arrosadía, 31006 Pamplona, Spain
| | - Paula Moriones
- Institute for Advanced Materials – Universidad Pública de Navarra, Campus Arrosadía, 31006 Pamplona, Spain
| | - Julián J Garrido
- Institute for Advanced Materials – Universidad Pública de Navarra, Campus Arrosadía, 31006 Pamplona, Spain
- Department of Applied Chemistry – Universidad Pública de Navarra, Campus Arrosadía, 31006 Pamplona, Spain
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20
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Wang H, Wang T, Yu M, Huang X, Zhong J, Huang W, Chen R. Elaborate control over the morphology and pore structure of porous silicas for VOCs removal with high efficiency and stability. ADSORPTION 2016. [DOI: 10.1007/s10450-016-9815-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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21
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Chiang WS, Fratini E, Baglioni P, Chen JH, Liu Y. Pore Size Effect on Methane Adsorption in Mesoporous Silica Materials Studied by Small-Angle Neutron Scattering. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:8849-8857. [PMID: 27512895 DOI: 10.1021/acs.langmuir.6b02291] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Methane adsorption in model mesoporous silica materials with the size range characteristic of shale is studied by small-angle neutron scattering (SANS). Size effect on the temperature-dependent gas adsorption at methane pressure about 100 kPa is investigated by SANS using MCM-41 and SBA-15 as adsorbents. Above the gas-liquid condensation temperature, the thickness of the adsorption layer is found to be roughly constant as a function of the temperature. Moreover, the gas adsorption properties, such as the adsorbed layer thickness and the specific amount of adsorbed gas, have little dependence on the pore size being studied, i.e., pore radius of 16.5 and 34.1 Å, but are mainly affected by the roughness of the pore surfaces. Hence, the surface properties of the pore wall are more dominant than the pore size in determining the methane gas adsorption of pores at the nanometer size range. Not surprisingly, the gas-liquid condensation temperature is observed to be sensitive to pore size and shifts to higher temperature when the pore size is smaller. Below the gas-liquid condensation temperature, even though the majority of gas adsorption experiments/simulations have assumed the density of confined liquid to be the same as the bulk density, the measured methane mass density in our samples is found to be appreciably smaller than the bulk methane density regardless of the pore sizes studied here. The mass density of liquid/solid methane in pores with different sizes shows different temperature dependence below the condensation temperature. With decreasing temperature, the methane density in larger pores (SBA-15) abruptly increases at approximately 65 K and then plateaus. In contrast, the density in smaller pores (MCM-41) monotonically increases with decreasing temperature before reaching a plateau at approximately 30 K.
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Affiliation(s)
- Wei-Shan Chiang
- Center for Neutron Research, National Institute of Standards and Technology , Gaithersburg, Maryland 20899, United States
- Department of Chemical and Biomolecular Engineering, University of Delaware , Newark, Delaware 19716, United States
| | - Emiliano Fratini
- Department of Chemistry "Ugo Schiff" and CSGI, University of Florence , via della Lastruccia 3-13-Sesto Fiorentino, I-50019 Florence, Italy
| | - Piero Baglioni
- Department of Chemistry "Ugo Schiff" and CSGI, University of Florence , via della Lastruccia 3-13-Sesto Fiorentino, I-50019 Florence, Italy
| | - Jin-Hong Chen
- Aramco Services Company, Aramco Research Center-Houston, Texas 77096, United States
| | - Yun Liu
- Center for Neutron Research, National Institute of Standards and Technology , Gaithersburg, Maryland 20899, United States
- Department of Chemical and Biomolecular Engineering, University of Delaware , Newark, Delaware 19716, United States
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22
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Giraldo L, Bastidas-Barranco M, Moreno-Piraján JC. Adsorption calorimetry: Energetic characterisation of the surface of mesoporous silicas and their adsorption capacity of non-linear chain alcohols. Colloids Surf A Physicochem Eng Asp 2016. [DOI: 10.1016/j.colsurfa.2015.10.049] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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23
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Dong X, Liu H, Hou J, Wu K, Chen Z. Phase Equilibria of Confined Fluids in Nanopores of Tight and Shale Rocks Considering the Effect of Capillary Pressure and Adsorption Film. Ind Eng Chem Res 2016. [DOI: 10.1021/acs.iecr.5b04276] [Citation(s) in RCA: 125] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Xiaohu Dong
- China University of Petroleum, Beijing 102249, China
- Department
of Chemical and Petroleum Engineering, University of Calgary, Calgary, T2N 1N4 Alberta, Canada
| | - Huiqing Liu
- China University of Petroleum, Beijing 102249, China
| | - Jirui Hou
- China University of Petroleum, Beijing 102249, China
| | - Keliu Wu
- Department
of Chemical and Petroleum Engineering, University of Calgary, Calgary, T2N 1N4 Alberta, Canada
| | - Zhangxin Chen
- China University of Petroleum, Beijing 102249, China
- Department
of Chemical and Petroleum Engineering, University of Calgary, Calgary, T2N 1N4 Alberta, Canada
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24
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Luo S, Nasrabadi H, Lutkenhaus JL. Effect of confinement on the bubble points of hydrocarbons in nanoporous media. AIChE J 2016. [DOI: 10.1002/aic.15154] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Sheng Luo
- Harold Vance Dept. of Petroleum Engineering; Texas A&M University; College Station Texas 77843
| | - Hadi Nasrabadi
- Harold Vance Dept. of Petroleum Engineering; Texas A&M University; College Station Texas 77843
| | - Jodie L. Lutkenhaus
- Artie McFerrin Dept. of Chemical Engineering; Texas A&M University; College Station Texas 77843
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25
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Sukhareva DA, Gus’kov VY, Karpov SI, Kudasheva FK, Roessner F, Borodina EV. Polarity of an МСМ-41 adsorbent surface modified with methyl and phenyl groups based on data from gas chromatography. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2016. [DOI: 10.1134/s0036024416020291] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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26
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Yuan G, Zhang J, Zhang Y, Yan Y, Ju X, Sun J. Characterization of high-alumina coal fly ash based silicate material and its adsorption performance on volatile organic compound elimination. KOREAN J CHEM ENG 2015. [DOI: 10.1007/s11814-014-0264-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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27
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Zhao H, Ma J, Zhang Q, Liu Z, Li R. Adsorption and Diffusion of n-Heptane and Toluene over Mesoporous ZSM-5 Zeolites. Ind Eng Chem Res 2014. [DOI: 10.1021/ie502496v] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- He Zhao
- Institute of Special Chemicals, Taiyuan University of Technology, Taiyuan 030024, China
| | - Jinghong Ma
- Institute of Special Chemicals, Taiyuan University of Technology, Taiyuan 030024, China
| | - Qiangqiang Zhang
- Institute of Special Chemicals, Taiyuan University of Technology, Taiyuan 030024, China
| | - Zhiping Liu
- Institute of Special Chemicals, Taiyuan University of Technology, Taiyuan 030024, China
| | - Ruifeng Li
- Institute of Special Chemicals, Taiyuan University of Technology, Taiyuan 030024, China
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28
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29
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Huang Y, Zhou D, Xie Y, Yang J, Kong J. Tunable sound absorption of silicone rubber materials via mesoporous silica. RSC Adv 2014. [DOI: 10.1039/c4ra00970c] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Mesoporous silica significantly enhanced sound absorption of silicone rubber via prolonging the propagation way and energy dissipated of acoustic wave.
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Affiliation(s)
- Yong Huang
- MOE Key Laboratory of Space Applied Physics and Chemistry
- Shaanxi Key Laboratory of Macromolecular Science and Technology
- Department of Applied Chemistry
- School of Science
- Northwestern Polytechnical University
| | - Dong Zhou
- MOE Key Laboratory of Space Applied Physics and Chemistry
- Shaanxi Key Laboratory of Macromolecular Science and Technology
- Department of Applied Chemistry
- School of Science
- Northwestern Polytechnical University
| | - Yunchuan Xie
- Department of Applied Chemistry
- School of Science
- Xi'an Jiaotong University
- Xi'an, P. R. China
| | - Jianye Yang
- College of Materials Science and Engineering
- Xi'an University of Science and Technology
- Xi'an, P. R. China
| | - Jie Kong
- MOE Key Laboratory of Space Applied Physics and Chemistry
- Shaanxi Key Laboratory of Macromolecular Science and Technology
- Department of Applied Chemistry
- School of Science
- Northwestern Polytechnical University
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30
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Zaitan H, Korrir A, Chafik T, Bianchi D. Evaluation of the potential of volatile organic compound (di-methyl benzene) removal using adsorption on natural minerals compared to commercial oxides. JOURNAL OF HAZARDOUS MATERIALS 2013; 262:365-376. [PMID: 24061215 DOI: 10.1016/j.jhazmat.2013.08.071] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Revised: 08/26/2013] [Accepted: 08/27/2013] [Indexed: 05/28/2023]
Abstract
This study is dedicated to the investigation of the potential of volatile organic compounds (VOC) adsorption over low cost natural minerals (bentonite and diatomite). The performances of these solids, in terms of adsorption/desorption properties, were compared to commercial adsorbents, such as silica, alumina and titanium dioxide. The solids were first characterized by different physico-chemical methods and di-methyl benzene (dMB) was selected as model VOC pollutant for the investigation of adsorptive characteristics. The experiments were carried out with a fixed bed reactor under dynamic conditions using Fourier Transform InfraRed spectrometer to measure the evolution of dMB concentrations in the gaseous stream at the outlet of the reactor. The measured breakthrough curves yields to adsorbed amounts at saturation that has been used to obtain adsorption isotherms. The latters were used for determination of the heat involved in the adsorption process and estimation of its values using the isosteric method. Furthermore, the performances of the studied materials were compared considering the adsorption efficiency/cost ratio.
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Affiliation(s)
- Hicham Zaitan
- Laboratory LCMC, Faculty of Sciences and Techniques, University Sidi Mohamed BenAbdellah, B.P. 2202, Fez, Morocco.
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31
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Herdes C, Carrott MMLR, Russo PA, Carrott PJM. Volatile organic compound adsorption on a nonporous silica surface: how do different probe molecules sense the same surface? LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:14940-14946. [PMID: 22060183 DOI: 10.1021/la203370c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In this work, we compare experimental results to molecular simulation results of volatile organic compound (VOC) adsorption on nonporous silica. We adopted an effective model for the rough solid surface, obtained by a temperature annealing scheme, plus an experimental/simulation nitrogen adsorption tuning process over the silica energetic oxygen parameter. The measurement/prediction of selected VOCs, specifically, n-pentane and methylcyclohexane, is presented in terms of adsorption isotherms, with an emphasis on the angle distribution analysis of the three studied probe molecules with respect to the same modeled surface.
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Affiliation(s)
- Carmelo Herdes
- Centro de Química de Évora, Universidade de Évora, 7000-671 Évora, Portugal.
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32
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Shkolnikov EI, Sidorova EV, Malakhov AO, Volkov VV, Julbe A, Ayral A. Estimation of pore size distribution in MCM-41-type silica using a simple desorption technique. ADSORPTION 2011. [DOI: 10.1007/s10450-011-9368-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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33
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Wang S, Shi Y, Ma X, Gong J. Tuning porosity of Ti-MCM-41: implication for shape selective catalysis. ACS APPLIED MATERIALS & INTERFACES 2011; 3:2154-2160. [PMID: 21608997 DOI: 10.1021/am200380a] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
This paper describes a method to regulate porosity of Ti-containing mesoporous molecular sieves (Ti-MCM-41) by employing swelling agents that are hydrophobic in nature, such as dodecylamine, n-heptane, and sym-trimethylbenzene (TMB). Physicochemical properties of the samples were investigated using XRD, FT-IR, IR spectra of pyridine absorption, UV-vis, TEM, and N(2) adsorption-desorption techniques. Addition of favorable swelling agents leads to an increase in pore size accompanied by retaining the mesostructure with a certain decrease of structure ordering. Swelling agents also have significant impact on the integration of Ti into the silica framework, which further affect the formation of Lewis acid sites. N-heptane is the most favorable agent for pore expansion of Ti-MCM-41. The material with n-heptane/CTAB ratio of 1 exhibits the largest pore size of 48.3 Ǻ, and mesopore volume of 1.266 cm(3)/g and narrow pore-size distribution. We also demonstrated that shape-selective transesterification catalytic activity of Ti-MCM-41 was greatly enhanced because of pore expansion.
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Affiliation(s)
- Shengping Wang
- Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
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34
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Dou B, Hu Q, Li J, Qiao S, Hao Z. Adsorption performance of VOCs in ordered mesoporous silicas with different pore structures and surface chemistry. JOURNAL OF HAZARDOUS MATERIALS 2011; 186:1615-1624. [PMID: 21216529 DOI: 10.1016/j.jhazmat.2010.12.051] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2010] [Accepted: 12/10/2010] [Indexed: 05/27/2023]
Abstract
Ordered mesoporous silicas with different pore structures, including SBA-15, MCM-41, MCM-48 and KIT-6, were functionalized with phenyltriethoxysilane by a post-synthesis grafting approach. It was found that phenyl groups were covalently anchored onto the surface of mesoporous silicas, and the long-range ordering of the mesoporous channels was well retained after the surface functionalization. The static adsorption of benzene and the dynamic adsorption of single component (benzene) and bicomponent (benzene and cyclohexane) on the original and functionalized materials were investigated. As indicated by the adsorption study, the functionalized silicas exhibit improvement in the surface hydrophobicity and affinity for aromatic compounds as compared with the original silicas. Furthermore, the pore structure and the surface chemistry of materials can significantly influence adsorption performance. A larger pore diameter and cubic pore structure are favorable to surface functionalization and adsorption performance. In particular, the best adsorption performance observed with phenyl-grafted KIT-6 is probably related to the highest degree of surface functionalization, arising from the relatively large mesopores and bi-continuous cubic pore structure which allow great accessibility for the functional groups. In contrast, functionalized MCM-41 exhibits the lowest adsorption efficiency, probably owing to the small size of mesopores and 1D mesoporous channels.
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Affiliation(s)
- Baojuan Dou
- Department of Environmental Nano-Materials, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China
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35
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Russo PA, Carrott MMLR, Carrott PJM. Hydrocarbonsadsorption on templated mesoporous materials: effect of the pore size, geometry and surface chemistry. NEW J CHEM 2011. [DOI: 10.1039/c0nj00614a] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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36
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Study in adsorption behavior of polymer on molecular sieves by surface and pore properties. Colloids Surf A Physicochem Eng Asp 2010. [DOI: 10.1016/j.colsurfa.2010.08.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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37
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Bhatia SK. Modeling pure gas permeation in nanoporous materials and membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:8373-8385. [PMID: 20232828 DOI: 10.1021/la9047962] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The low-pressure transport of simple fluids in nanopores and in disordered nanoporous networks is analyzed, using a recent oscillator model theory from the author's laboratory, considering the trajectories of molecules moving in the potential energy field of the fluid-pore wall interaction. The scaling behavior of the single-pore theory is discussed, and it is shown that the Knudsen model provides an upper bound to the diffusivity scaled with the pore radius. The single-pore theory is shown to apply well to ordered materials and successfully interprets recent literature data on the variation of permeability with diffusant molecular size for a DDR zeolite membrane. A peak in permeability is seen at a pore-size-dependent molecular size because of the opposing effects of equilibrium and transport. Application to disordered pore networks is also presented on the basis of a hybrid correlated random walk effective medium theory imbedding the oscillator model at the single-pore level, and a rigorous expression for the tortuosity is derived from the theory. A rich variety of behavior is predicted for the tortuosity, which can increase or decrease with increasing extent of pore size nonuniformity as well as with changes in temperature because the diffusing species preferentially flows through more conducting pores. Weakly adsorbing gases such as helium are seen to have a higher tortuosity than more strongly adsorbing ones. The predicted values of tortuosity are shown to be in line with those obtained from the interpretation of recent experimental mesoporous membrane transport data and are in the range of 5-10 whereas those extracted using the Knudsen model are unrealistically high, in the range of 10-20.
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Affiliation(s)
- Suresh K Bhatia
- School of Chemical Engineering, The University of Queensland, Brisbane QLD 4072, Australia.
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38
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Pellenq RJM, Coasne B, Denoyel RO, Coussy O. Simple phenomenological model for phase transitions in confined geometry. 2. Capillary condensation/evaporation in cylindrical mesopores. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:1393-1402. [PMID: 19138076 DOI: 10.1021/la8020244] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A simple phenomenological model that describes capillary condensation and evaporation of pure fluids confined in cylindrical mesopores is presented. Following the work of Celestini (Celestini, F. Phys. Lett. A 1997, 228, 84), the free energy density of the system is derived using interfacial tensions and a corrective term that accounts for the interaction coupling between the vapor/adsorbed liquid and the adsorbed liquid/adsorbent interfaces. This corrective term is shown to be consistent with the Gibbs adsorption isotherm and assessed by standard adsorption tests. This model reveals that capillary condensation and evaporation are metastable and equilibrium processes, respectively, hence exhibiting the existence of a hysteresis loop inadsorption/desorption isotherm that is well-known in experiment. We extend the phenomenological model of Celestini to give a quantitative description of adsorption on the pore wall and hysteresis width evolution with temperature and confinement. Direct quantitative comparison is made with experimental data for confined argon. Used as a characterizing tool, this integrated model allows in a single fit of an experimental adsorption/desorption isotherm assessing essential characterization data such as the specific surface area, pore volume, and mean pore size.
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Affiliation(s)
- Roland J-M Pellenq
- Centre Interdisciplinaire des Nanosciences de Marseille, CINaM, UPR CNRS 3118, Campus de Luminy, 13288 Marseille Cedex 09, France.
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39
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Sangthong W, Probst M, Limtrakul J. CONFINEMENT EFFECTS ON ADSORPTION AND DIFFUSION OF HEXANE IN NANOPOROUS MCM-41 WITH DIFFERENT PORE SIZES: A MOLECULAR DYNAMICS STUDY. CHEM ENG COMMUN 2008. [DOI: 10.1080/00986440801967486] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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40
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Russo PA, Ribeiro Carrott MML, Carrott PJM. Adsorption of toluene, methylcyclohexane and neopentane on silica MCM-41. ADSORPTION 2008. [DOI: 10.1007/s10450-007-9099-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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41
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Kosuge K, Kubo S, Kikukawa N, Takemori M. Effect of pore structure in mesoporous silicas on VOC dynamic adsorption/desorption performance. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:3095-102. [PMID: 17266336 DOI: 10.1021/la062616t] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The dynamic adsorption/desorption behavior of volatile organic compounds (VOCs) such as toluene (C7H8) and benzene (C6H6) was evaluated for three kinds of mesoporous silicas of SBA-15, all having almost the same mesopore size of ca. 5.7 nm, and a MCM-41 silica with a smaller pore size of 2.1 nm using a continuous three-step test. The fiberlike SBA-15 silica exhibited exceptionally good breakthrough behavior, a higher VOC capacity, and easier desorption. The fiberlike silica was composed through the catenation of rodlike particles. The rodlike silicas, by comparison, were proven to be less useful in dynamic adsorption processes because of lower dynamic VOC capacities despite having comparative porous parameters with the fiberlike silica. The large dynamic VOC capacity of the fiberlike silica was attributed to the presence of a bimodal pore system consisting of longer, one-dimensional mesopore channels connected by complementary micropores.
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Affiliation(s)
- Katsunori Kosuge
- Research Institute for Environmental Management Technology, National Institute of Advanced Industrial Science and Technology, 16-1 Onogawa, Tsukuba, Ibaraki 305-8569 Japan.
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42
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Trens P, Valentin R, Quignard F. Cation enhanced hydrophilic character of textured alginate gel beads. Colloids Surf A Physicochem Eng Asp 2007. [DOI: 10.1016/j.colsurfa.2006.09.049] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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43
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Shim WG, Lee JW, Moon H. Heterogeneous Adsorption Characteristics of Volatile Organic Compounds (VOCs) on MCM‐48. SEP SCI TECHNOL 2007. [DOI: 10.1080/01496390600956936] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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44
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Ustinov E, Do D. Application of a generalized thermodynamic approach to characterize mesoporous materials. Colloids Surf A Physicochem Eng Asp 2006. [DOI: 10.1016/j.colsurfa.2005.07.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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45
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Gribov EN, Sastre G, Corma A. Influence of Pore Dimension and Sorption Configuration on the Heat of Sorption of Hexane on Monodimensional Siliceous Zeolites. J Phys Chem B 2005; 109:23794-803. [PMID: 16375363 DOI: 10.1021/jp052462a] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Sorption of n-hexane on monodimensional pure silica SSZ-35, CIT-5, ZSM-12, and ZSM-22 zeolites with different pore dimension and on recently synthesized ITQ-29 was studied by IR spectroscopic and computational chemistry methods. Heats of sorption of n-hexane on these zeolites was determined experimentally from the temperature dependence of the intensity of IR bands of sorbed hexane as well as from theoretical calculations. Calculations have shown the different orientations of sorbed hexane molecules inside zeolite channels, which depend on the type of zeolite and loading. At high loadings, ordering of hexane inside the channels is observed due to optimization of sorbate-sorbate and sorbate-zeolite interaction energies. Such ordering is responsible for the increase of the sorption energy. A decrease of the sorption energy upon increasing the pore dimension of zeolite was observed, in agreement with results previously published in the literature. Effects of pore diameter of zeolites and ordering of molecules inside zeolite channels on the sorption energy of hexane are discussed.
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Affiliation(s)
- Evgueni N Gribov
- Instituto de Tecnologia Quimica UPV-CSIC, Universidad Politécnica de Valencia, Av. Los Naranjos s/n, 46022 Valencia, Spain
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Kowalczyk P, Jaroniec M, Kaneko K, Terzyk AP, Gauden PA. Improvement of the Derjaguin-Broekhoff-de Boer theory for the capillary condensation/evaporation of nitrogen in spherical cavities and its application for the pore size analysis of silicas with ordered cagelike mesopores. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:10530-6. [PMID: 16262317 DOI: 10.1021/la0513609] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
In a previous work, we proposed an improvement of the Derjaguin-Broekhoff-de Boer (DBdB) theory for capillary condensation/evaporation in open-ended cylindrical mesopores. In this paper, we report a further extension of this approach to the capillary condensation/evaporation of nitrogen in siliceous spherical cavities. The main idea of this improvement is to employ the Gibbs-Tolman-Koenig-Buff equation to predict the variation of the surface tension in spherical mesopores. In addition, the statistical film thickness (the so-called t-curve), which is evaluated accurately on the basis of adsorption isotherms measured for MCM-41 materials, is used instead of the originally proposed t-curve to take into account the excess chemical potential due to the surface forces. It is shown that the aforementioned modifications of the original DBdB theory that was refined by Ravikovitch and Neimark have significant implications for the pore size analysis of cagelike mesoporous silicas. To verify the proposed improvement of the DBdB pore size analysis (IDBdB), two series of FDU-1 samples, which are well-defined cagelike mesoporous materials (composed of siliceous spherical cavities interconnected by short necks), were used for the evaluation of the pore size distributions (PSDs). The correlation between the spinodal condensation point in the spherical pores predicted by the nonlocal density functional theory (NDFT) developed by Ravikovitch and Neimark and that predicted by the IDBdB theory is very good in the whole range of mesopores. This feature is mirrored to the realistic PSD characterized by the bimodal structure of pores computed from the IDBdB theory. As in the case of open-ended cylindrical pores, the improvement of the classical DBdB theory preserves its simplicity and simultaneously ensures a significant improvement of the pore size analysis, which is confirmed by the independent estimation of the average pore size by the NDFT and the powder X-ray diffraction method.
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Affiliation(s)
- Piotr Kowalczyk
- Department of Chemistry, Faculty of Science, Chiba University, Japan.
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Trens P, Tanchoux N, Galarneau A, Brunel D, Fubini B, Garrone E, Fajula F, Di Renzo F. A macrothermodynamic approach to the limit of reversible capillary condensation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:8560-4. [PMID: 16114972 DOI: 10.1021/la0507838] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The threshold of reversible capillary condensation is a well-defined thermodynamic property, as evidenced by corresponding states treatment of literature and experimental data on the lowest closure point of the hysteresis loop in capillary condensation-evaporation cycles for several adsorbates. The nonhysteretical filling of small mesopores presents the properties of a first-order phase transition, confirming that the limit of condensation reversibility does not coincide with the pore critical point. The enthalpy of reversible capillary condensation can be calculated by a Clausius-Clapeyron approach and is consistently larger than the condensation heat in unconfined conditions. Calorimetric data on the capillary condensation of tert-butyl alcohol in MCM-41 silica confirm a 20% increase of condensation heat in small mesopores. This enthalpic advantage makes easier the overcoming of the adhesion forces by the capillary forces and justifies the disappearing of the hysteresis loop.
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Affiliation(s)
- Philippe Trens
- Laboratoire de Matériaux Catalytiques et Catalyse en Chimie Organique, UMR 5618 CNRS-ENSCM-UM1, Institut C. Gerhardt, FR 1878, ENSCM, 8 rue Ecole Normale, 34296 Montpellier, France
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Trens P, Tanchoux N, Galarneau A, Fajula F. New Evidence of Confinement Effects in Mesoporous Materials and the Definition of Confined Pitzer Acentric Factors. J Phys Chem B 2005; 109:16415-20. [PMID: 16853086 DOI: 10.1021/jp051591o] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In the present work, the corresponding states principle is proposed as a new approach to clarify the comparison between adsorption-desorption isotherms obtained on porous solids. The applicability of this principle at the capillary critical point in adsorption-desorption isotherms is demonstrated. Deviations of the Clausius-Clapeyron curves in reduced coordinates are interpreted in terms of polarizability, and those are perfectly correlated using analogous Pitzer acentric factors in confined environments. New acentric factors are proposed to take confinement effects in mesoporous materials into account. Enthalpic excesses during capillary condensation could be predicted, and those are supported by calorimetric experiments.
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Affiliation(s)
- Philippe Trens
- Laboratoire de Matériaux Catalytiques et Catalyse en Chimie Organique, UMR 5618, CNRS/ENSCM/UM1, FR 1878 Institut Gerhardt, 8 rue de l'Ecole Normale, 34296 Montpellier Cedex 5, France.
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Ustinov EA, Do DD. Modeling of Adsorption and Nucleation in Infinite Cylindrical Pores by Two-Dimensional Density Functional Theory. J Phys Chem B 2005; 109:11653-60. [PMID: 16852430 DOI: 10.1021/jp050823g] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this paper, we present an analysis of argon adsorption in cylindrical pores having amorphous silica structure by means of a nonlocal density functional theory (NLDFT). In the modeling, we account for the radial and longitudinal density distributions, which allow us to consider the interface between the liquidlike and vaporlike fluids separated by a hemispherical meniscus in the canonical ensemble. The Helmholtz free energy of the meniscus was determined as a function of pore diameter. The canonical NLDFT simulations show the details of density rearrangement at the vaporlike and liquidlike spinodal points. The limits of stability of the smallest bridge and the smallest bubble were also determined with the canonical NLDFT. The energy of nucleation as a function of the bulk pressure and the pore diameter was determined with the grand canonical NLDFT using an additional external potential field. It was shown that the experimentally observed reversibility of argon adsorption isotherms at its boiling point up to the pore diameter of 4 nm is possible if the potential barrier of 22kT is overcome due to density fluctuations.
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Affiliation(s)
- E A Ustinov
- Department of Chemical Engineering, University of Queensland, St. Lucia, Queensland, Brisbane, 4072 Australia
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Ustinov EA, Do DD, Jaroniec M. Equilibrium Adsorption in Cylindrical Mesopores: A Modified Broekhoff and de Boer Theory versus Density Functional Theory. J Phys Chem B 2005; 109:1947-58. [PMID: 16851179 DOI: 10.1021/jp046534u] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
This paper presents a thermodynamic analysis of capillary condensation phenomena in cylindrical pores. Here, we modified the Broekhoff and de Boer (BdB) model for cylindrical pores accounting for the effect of the pore radius on the potential exerted by the pore walls. The new approach incorporates the recently published standard nitrogen and argon adsorption isotherm on nonporous silica LiChrospher Si-1000. The developed model is tested against the nonlocal density functional theory (NLDFT), and the criterion for this comparison is the condensation/evaporation pressure versus the pore diameter. The quantitative agreement between the NLDFT and the refined version of the BdB theory is ascertained for pores larger than 2 nm. The modified BdB theory was applied to the experimental adsorption branch of adsorption isotherms of a number of MCM-41 samples to determine their pore size distributions (PSDs). It was found that the PSDs determined with the new BdB approach coincide with those determined with the NLDFT (also using the experimental adsorption branch). As opposed to the NLDFT, the modified BdB theory is very simple in its utilization and therefore can be used as a convenient tool to obtain PSDs of all mesoporous solids from the analysis of the adsorption branch of adsorption isotherms of any subcritical fluids.
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Affiliation(s)
- E A Ustinov
- Saint Petersburg State Technological Institute (Technical University), 26, Moskovsky Prospect, 190013 Saint Petersburg, Russia
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