scholarly journals How Molecular Weight Cut-Offs and Physicochemical Properties of Polyether Sulfone Membranes Affect Peptide Migration and Selectivity during Electrodialysis with Filtration Membranes

Membranes ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 153 ◽  
Author(s):  
Sabita Kadel ◽  
Geneviève Pellerin ◽  
Jacinthe Thibodeau ◽  
Véronique Perreault ◽  
Carole Lainé ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Physicochemical Properties ◽  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Negative Charge ◽  
Protein Hydrolysate ◽  
Filtration Membranes ◽  
Polyether Sulfone ◽  
Wide Range

Filtration membranes (FMs) are an integral part of electrodialysis with filtration membranes (EDFM), a green and promising technology for bioactive peptide fractionation. Therefore, it is paramount to understand how physicochemical properties of FMs impact global and selective peptide migration to anionic (A−RC) and cationic (C+RC) peptide recovery compartments during their simultaneous separation by EDFM. In this context, six polyether sulfone (PES) membranes with molecular weight cut-offs (MWCO) of 5, 10, 20, 50, 100 and 300 kDa were characterized and used during EDFM to separate peptides from a complex whey protein hydrolysate. Surface charge, roughness, thickness and surface/pores nature of studied PES membranes were similar with small differences in conductivity, porosity and pore size distribution. Interestingly, global peptides migration to both recovery compartments increased linearly as a function of MWCO. However, peptide selectivity changed according to the recovery compartments and/or the peptide’s charge and MW with an increase in MWCO of FMs. Indeed, in A−RC, the relative abundance (RA) of peptides having low negative charge and MW (IDALNENK and VLVLDTDYK) decreased (45% to 19%) with an increase in MWCO, while the opposite for peptides having high negative charge and MW (TPEVDDEALEK, TPEVDDEALEKFDK & VYVEELKPTPEGDLEILLQK) (increased from 16% to 43%). Concurrently, in C+RC, regardless of MWCO used, the highest RA was observed for peptides having low positive charge and MW (IPAVFK & ALPMHIR). It was the first time that the significant impact of charge, MWCO and pore size distribution of PES membranes on a wide range of MWCO was demonstrated on EDFM performances.

Determination of T2 cut-off for shale reservoirs: a case study from the Carynginia formation, Perth Basin, Western Australia

2017 ◽  
Vol 57 (2) ◽  
pp. 664 ◽  
Author(s):  
M. Nadia Testamanti ◽  
Reza Rezaee ◽  
Yujie Yuan ◽  
Dawei Pan
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Petroleum Industry ◽  
Bound Water ◽  
Invasive Technique ◽  
Sources Of Information ◽  
Vacuum Oven ◽  
Low Field ◽  
Wide Range

Over recent decades, the low-field Nuclear Magnetic Resonance (NMR) method has been consistently used in the petroleum industry for the petrophysical characterisation of conventional reservoirs. Through this non-invasive technique, the porosity, pore size distribution and fluid properties can be determined from the signal emitted by fluids present in the porous media. Transverse relaxation (T2) data, in particular, are one of the most valuable sources of information in an NMR measurement, as the resulting signal decay can be inverted to obtain the T2 distribution of the rock, which can in turn be correlated with porosity and pore size distribution. The complex pore network of shales, which can have a large portion of pore sizes in the nanopore and mesopore range, restricts the techniques that can be used to investigate their pore structure and porosity. The ability of the NMR technique to detect signals from a wide range of pores has therefore prompted the quest for more standardised interpretation methods suitable for shales. Using low-field NMR, T2 experiments were performed on shale samples from the Carynginia formation, Perth Basin, at different saturation levels. The shale samples were initially saturated with brine and the T2 spectrum for each sample was obtained. Then, they were placed in a vacuum oven and their weight monitored until a constant value was reached. T2 curves were subsequently obtained for each of the oven-dried samples and a cut-off value for clay-bound water was calculated.

Porosity and pore size distribution of shales: a case study of the Carynginia Formation, Perth Basin, Western Australia

2017 ◽  
Vol 57 (2) ◽  
pp. 660
Author(s):  
M. Nadia Testamanti ◽  
Reza Rezaee ◽  
Jie Zou
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Gas Adsorption ◽  
Pore Network ◽  
Pore Sizes ◽  
Wide Range ◽  
Pore Characterisation ◽  
Shale Reservoirs ◽  
Mercury Injection Capillary Pressure

The evaluation of the gas storage potential of shale reservoirs requires a good understanding of their pore network. Each of the laboratory techniques used for pore characterisation can be applied to a specific range of pore sizes; but if the lithology of the rock is known, usually one suitable method can be selected to investigate its pore system. Shales do not fall under any particular lithological classification and can have a wide range of minerals present, so a combination of at least two methods is typically recommended for a better understanding of their pore network. In the laboratory, the Low-Pressure Nitrogen Gas Adsorption (LP-N2-GA) technique is typically used to examine micropores and mesopores, and Mercury Injection Capillary Pressure (MICP) tests can identify pore throats larger than 3 nm. In contrast, a wider range of pore sizes in rock can be screened with Nuclear Magnetic Resonance (NMR), either in laboratory measurements made on cores or through well logging, provided that the pores are saturated with a fluid. The pore network of a set of shale core samples from the Carynginia Formation was investigated using a combination of laboratory methods. The cores were studied using the NMR, LP-N2-GA and MICP techniques, and the experimental porosity and pore size distribution results are presented. When NMR results were calibrated with MICP or LP-N2-GA measurements, then the pore size distribution of the shale samples studied could be estimated.

On the characterization of pore size distribution of building materials

2017 ◽  
Vol 41 (3) ◽  
pp. 247-263 ◽  
Author(s):  
LF Dutra ◽  
N Mendes ◽  
PC Philippi
Keyword(s):  
Relative Humidity ◽  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Building Materials ◽  
Mercury Porosimetry ◽  
Energy Performance ◽  
Volume Distribution ◽  
Wide Range

Moisture affects significantly the energy performance of air conditioning systems, the durability of materials, and the health of occupants. One way of reducing those effects, without increasing the energy costs, is by means of using porous material ability of absorbing and releasing moisture from/to the adjacent environment, which attenuates the indoor relative humidity variation. This natural ability is intrinsically related to the porous microstructure. Therefore, the characterization of the pore space is an important research theme in the building physics area. This article aims to present a method for obtaining the pore size distribution based on adsorption isotherms and mercury porosimetry data. First, the theoretical formulation based on the Gibbs free energy for a two-phase (liquid–vapor) system, using the De Boer and Zwikker model, is presented, allowing the calculation of the critical adsorbed thickness for pore filling, critical radius, adsorbed moisture content, capillary condensation content, available surface for adsorption, and the distribution of micropores for a wide range of radius. The adsorption isotherm curve is estimated for high relative humidity values through mercury porosimetry, along with the adsorption curve obtained from the experiment. The pore volume distribution calculated by this method can be used to estimate transport coefficients for liquid and vapor phases.

scholarly journals Adamantane-Based Micro- and Ultra-Microporous Frameworks for Efficient Small Gas and Toxic Organic Vapor Adsorption

Polymers ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 486 ◽  
Author(s):  
Wenzhao Jiang ◽  
Hangbo Yue ◽  
Peter Shuttleworth ◽  
Pengbo Xie ◽  
Shanji Li ◽  
...  
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Bet Surface Area ◽  
Organic Vapors ◽  
Practical Applications ◽  
Organic Vapor ◽  
Surface Areas ◽  
Wide Range ◽  
Microporous Organic Polymers

Microporous organic polymers and related porous materials have been applied in a wide range of practical applications such as adsorption, catalysis, adsorption, and sensing fields. However, some limitations, like wide pore size distribution, may limit their further applications, especially for adsorption. Here, micro- and ultra-microporous frameworks (HBPBA-D and TBBPA-D) were designed and synthesized via Sonogashira–Hagihara coupling of six/eight-arm bromophenyl adamantane-based “knots” and alkynes-type “rod” monomers. The BET surface area and pore size distribution of these frameworks were in the region of 395–488 m2 g−1, 0.9–1.1 and 0.42 nm, respectively. The as-made prepared frameworks also showed good chemical ability and high thermal stability up to 350 °C, and at 800 °C only 30% mass loss was observed. Their adsorption capacities for small gas molecules such as CO2 and CH4 was 8.9–9.0 wt % and 1.43–1.63 wt % at 273 K/1 bar, and for the toxic organic vapors n-hexane and benzene, 104–172 mg g−1 and 144–272 mg g−1 at 298 K/0.8 bar, respectively. These are comparable to many porous polymers with higher BET specific surface areas or after functionalization. These properties make the resulting frameworks efficient absorbent alternatives for small gas or toxic vapor capture, especially in harsh environments.

Macroporous Thermosets via Chemically Induced Phase Separation

1996 ◽  
Vol 431 ◽  
Author(s):  
J. Kiefer ◽  
R. Porouchani ◽  
D. Mendels ◽  
J. B. Ferrer ◽  
C. Fond ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Phase Separation ◽  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
New Technology ◽  
Curing Temperature ◽  
Low Molecular Weight ◽  
Closed Cell ◽  
Chemically Induced

AbstractWe have explored a new technology based on chemically induced phase separation that yields porous epoxies and cyanurates with a closed cell morphology and micrometer sized pores with a narrow pore size distribution. When the precursor monomers are cured in the presence of a low molecular weight liquid, the desired morphology results from a phase separation and a chemical quench. After phase separation, the porosity is achieved by thermal removal of the secondary liquid phase, specifically by diffusion through the crosslinked matrix. In respect to the thermodynamics and kinetics, the origin of the phase separation process can be identified as nucleation and growth. The influence of internal and external reaction parameters, such as chemical nature of the low molecular weight liquid, its concentration and the curing temperature on the final morphology are presented. Thus, the morphology can be controlled ranging from a monomodal to bimodal pore size distribution with pore sizes inbetween 1 to 10 μm. These porous thermosets are characterized by a significantly lower density, without any loss in thermal stability compared to the neat matrix. Such new materials demonstrate great interest for lowering the dielectric constant and for improving the fundamental understanding of the role of voids in stress relaxation and toughening.

A New Approach for Building Composite Cores for Corefloods in Complex Carbonate Rocks

2021 ◽  
Author(s):  
Yildiray Cinar ◽  
Ahmed Zayer ◽  
Naseem Dawood ◽  
Dimitris Krinis
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Capillary Pressure ◽  
Size Distribution ◽  
Carbonate Reservoir ◽  
Reservoir Rock ◽  
Rock Types ◽  
Pore Structures ◽  
Irreducible Water Saturation ◽  
Wide Range

Abstract Carbonate reservoir rocks are composed of complex pore structures and networks, forming a wide range of sedimentary facies. Considering this complexity, we present a novel approach for a better selection of coreflood composites. In this approach, reservoir plugs undergo a thorough filtration process by completing several lab tests before they get classified into reservoir rock types. Those tests include conventional core analysis (CCA), liquid permeability, plug computed tomography (CT), nuclear magnetic resonance (NMR), end-trim mercury injection capillary pressure (MICP), X-ray diffraction (XRD), thin-section analysis (TS), scanning electron microscopy (SEM), and drainage capillary pressure (Pc). We recommend starting with a large pool of plugs and narrowing down the selection as they complete different stages of the screening process. The CT scans help to exclude plugs exhibiting composite-like behavior or containing vugs and fractures that potentially influence coreflood results. After that, the plugs are categorized into separate groups representing the available reservoir rock types. Then, we look into each rock type and determine whether the selected plugs share similar pore-structures, rock texture, and mineral content. The end-trim MICP is usually helpful in clustering plugs having similar pore-throat size distributions. Nevertheless, it also poses a challenge because it may not represent the whole plug, especially for heterogeneous carbonates. In such a case, we recommend harnessing the NMR capabilities to verify the pore-size distribution. After pore-size distribution verification, plugs are further screened for textural and mineral similarity using the petrographic data (XRD, TS, and SEM). Finally, we evaluate the similarity of brine permeability (Kb), irreducible water saturation (Swir) from Pc, and effective oil permeability data at Swir (Koe, after wettability restoration for unpreserved plugs) before finalizing the composite selection. The paper demonstrates significant aspects of applying the proposed approach to carbonate reservoir rock samples. It integrates geology, petrophysics, and reservoir engineering elements when deciding the best possible composite for coreflood experiments. By practicing this workflow, we also observe considerable differences in rock types depending on the data source, suggesting that careful use of end-trim data for carbonates is advisable compared to more representative full-plug MICP and NMR test results. In addition, we generally observe that Kb and Koe are usually lower than the Klinkenberg permeability with a varying degree that is plug-specific, highlighting the benefit of incorporating these measurements as additional criteria in coreflood composite selection for carbonate reservoirs.

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