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Vázquez MI, Romero V, Vega V, García J, Prida VM, Hernando B, Benavente J. Morphological, Chemical Surface, and Diffusive Transport Characterizations of a Nanoporous Alumina Membrane. NANOMATERIALS (BASEL, SWITZERLAND) 2015; 5:2192-2202. [PMID: 28347115 PMCID: PMC5304769 DOI: 10.3390/nano5042192] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Accepted: 11/24/2015] [Indexed: 11/17/2022]
Abstract
Synthesis of a nanoporous alumina membrane (NPAM) by the two-step anodization method and its morphological and chemical surface characterization by analyzing Scanning Electron Microscopy (SEM) micrographs and X-Ray Photoelectron Spectroscopy (XPS) spectra is reported. Influence of electrical and diffusive effects on the NaCl transport across the membrane nanopores is determined from salt diffusion measurements performed with a wide range of NaCl concentrations, which allows the estimation of characteristic electrochemical membrane parameters such as the NaCl diffusion coefficient and the concentration of fixed charges in the membrane, by using an appropriated model and the membrane geometrical parameters (porosity and pore length). These results indicate a reduction of ~70% in the value of the NaCl diffusion coefficient through the membrane pores with respect to solution. The transport number of ions in the membrane pores (Na⁺ and Cl-, respectively) were determined from concentration potential measurements, and the effect of concentration-polarization at the membrane surfaces was also considered by comparing concentration potential values obtained with stirred solutions (550 rpm) and without stirring. From both kinds of results, a value higher than 0.05 M NaCl for the feed solution seems to be necessary to neglect the contribution of electrical interactions in the diffusive transport.
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Affiliation(s)
- María I Vázquez
- Department of Applied Physics I, Faculty of Sciences, University of Málaga, E-29071 Málaga, Spain.
| | - Virgina Romero
- Department of Applied Physics I, Faculty of Sciences, University of Málaga, E-29071 Málaga, Spain.
| | - Victor Vega
- Department of Physics, Faculty of Sciences, University of Oviedo, E-33007 Oviedo, Spain.
| | - Javier García
- Department of Physics, Faculty of Sciences, University of Oviedo, E-33007 Oviedo, Spain.
- Institute of Applied Physics, University of Hamburg, 20355-Hamburg, Germany.
| | - Victor M Prida
- Department of Physics, Faculty of Sciences, University of Oviedo, E-33007 Oviedo, Spain.
| | - Blanca Hernando
- Department of Physics, Faculty of Sciences, University of Oviedo, E-33007 Oviedo, Spain.
| | - Juana Benavente
- Department of Applied Physics I, Faculty of Sciences, University of Málaga, E-29071 Málaga, Spain.
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de Lara R, Benavente J. Use of hydrodynamic and electrical measurements to determine protein fouling mechanisms for microfiltration membranes with different structures and materials. Sep Purif Technol 2009. [DOI: 10.1016/j.seppur.2009.02.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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de Lara R, Benavente J. Electrokinetic and surface chemical characterizations of an irradiated microfiltration polysulfone membrane: Comparison of two irradiation doses. J Colloid Interface Sci 2007; 310:519-28. [PMID: 17349653 DOI: 10.1016/j.jcis.2007.01.079] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2006] [Revised: 01/15/2007] [Accepted: 01/26/2007] [Indexed: 11/30/2022]
Abstract
The effect of ionizing radiation on the surface and electrokinetic characteristic parameters for a porous membrane of pore size 0.2 mum is determined and correlated with the irradiation dose (10 and 80 J/kg). Changes in NaCl permeability and membrane system electrical resistance determined from diffusion and impedance spectroscopy measurements are consistent with the increase of membrane pore radii/porosity, in agreement with SEM micrographs and reported results. Low irradiation dose seems to clean the membrane surface of impurities, according to XPS results, but the increase of irradiation doses could affect surface roughness. Due to the relatively high pore radius, ion transport numbers are practically independent of radiation and dose, but irradiation slightly modifies the membrane solution interface by increasing its weakly electronegative character, which could be of interest in the ultrafiltration of proteins or macromolecules.
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Affiliation(s)
- R de Lara
- Grupo de Caracterización Electrocinética y de Transporte en Membranas e Interfases, Departamento de Física Aplicada I, Facultad de Ciencias, Universidad de Málaga, E-29071 Málaga, Spain
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Cañas A, Ariza MJ, Benavente J. A comparison of electrochemical and electrokinetic parameters determined for cellophane membranes in contact with NaCl and NaNO3 solutions. J Colloid Interface Sci 2007; 246:150-6. [PMID: 16290395 DOI: 10.1006/jcis.2001.8004] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2001] [Accepted: 10/01/2001] [Indexed: 11/22/2022]
Abstract
Electrochemical and electrokinetic characterizations of cellophane membrane samples have been carried out by measuring membrane potential, salt diffusion, and tangential streaming potential, which allow the determination of different characteristic membrane parameters. Experiments were made with the membrane samples in contact with NaCl and NaNO(3) solutions at different concentrations and under different external conditions (concentration gradients), in order to obtain differences in transport and membrane characteristic parameters, depending on the electrolyte considered. Salt permeability across the membrane, which was obtained from diffusion measurements, is about twice as high for NaCl solutions as for NaNO(3) solutions, which is attributed to the different sizes of the electrolytes. Membrane potential measurements keeping the concentration ratio constant (C(1)/C(2)=2) were used to determine both the effective fixed charge concentration in the membrane, X(f), and the average value of transport numbers, t(i); taking into account these values, concentration dependence of membrane potential under a different external condition (C(1)=cte=0.01 M, 5 x 10(-3)< or =C(M)< or =5 x 10(-2)) was predicted. Results show that cellophane membrane behaves as a weak cation-exchange membrane and its permselectivity to cations is practically independent of the electrolyte considered. From electrokinetic results, assuming a Langmuir-type adsorption of anions on the cellophane surface, the number of accessible sites per surface unit was obtained, which is higher for Cl(-) than for NO(3)(-), in agreement with the small radii of chlorine ions; however, no significant differences in the specific adsorption free energy were found (DeltaG(Nacl)=-22.0 x 10(3) J/mol) and (DeltaG(NaNO(3))=-23.2 x 10(3) J/mol).
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Affiliation(s)
- A Cañas
- Grupo de Caracterización Electrocinética y de Transporte en Membranas e Interfases, Departamento de Física Aplicada, Facultad de Ciencias, Universidad de Málaga, E-29071 Málaga, Spain
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Ariza MJ, Benavente J, Rodríguez-Castellón E, Palacio L. Effect of Hydration of Polyamide Membranes on the Surface Electrokinetic Parameters: Surface Characterization by X-Ray Photoelectronic Spectroscopy and Atomic Force Microscopy. J Colloid Interface Sci 2002; 247:149-58. [PMID: 16290450 DOI: 10.1006/jcis.2001.8071] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2001] [Accepted: 10/29/2001] [Indexed: 11/22/2022]
Abstract
The surface and the solid/liquid interface of two polyamide membranes, one experimental (B0) and one commercial (NF45), have been characterized by X-ray photoelectronic spectroscopy (XPS), atomic force microscopy (AFM), and zeta potential, respectively. The surface roughness, determined by AFM data analysis, is different for the two membranes, and results show that the commercial NF45 membrane presents a much lower roughness than the experimental B0 membrane. XPS data indicate that the surface of membrane NF45 is similar to that of pure polyamide, while membrane B0 contains a considerable amount of impurities. The homogeneity in depth of both membranes was also studied by determining the composition profile at different analysis angles. Streaming potential along the membrane surface or tangential streaming potential (TSP) measurements with NaCl solutions at different concentrations were carried out with both membranes to determine the zeta potential and the electrokinetic surface charge density, and a correlation between membrane surface and interface parameters is made. Some differences in atomic concentrations of membrane surface elements and X-ray photoelectronic spectra of the samples used in TSP measurements and after a drying process at 90 degrees C for 24 h can be observed when they are compared with those for fresh membranes. Electrokinetic parameters for membrane NF45 (TSP, zeta potential, and surface electrokinetic charge density) obtained from three different series of measurements strongly decrease as a result of membrane use, but for membrane B0 they are practically independent of the number of measurements. This difference in the electrokinetic behavior of the two membranes has been related to the hydration process of the surface for each sample studied by XPS and AFM.
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Affiliation(s)
- M J Ariza
- Departamento de Física Aplicada, Facultad de Ciencias, Universidad de Málaga, Málaga, 29071, Spain
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Ariza M, Cañas A, Benavente J. Electrokinetic and electrochemical characterizations of porous membranes. Colloids Surf A Physicochem Eng Asp 2001. [DOI: 10.1016/s0927-7757(01)00587-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Takagi R, Larbot A, Cot L, Nakagaki M. Effect of Al2O3 support on electrical properties of TiO2/Al2O3 membrane formed by sol–gel method. J Memb Sci 2000. [DOI: 10.1016/s0376-7388(00)00461-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Benavente J, Cañas A. Transport of NaNO3 solutions across an activated composite membrane: electrochemical and chemical surface characterizations. J Memb Sci 1999. [DOI: 10.1016/s0376-7388(98)00348-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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A network microcapillary model for electrokinetic phenomena through microporous membranes. Colloids Surf A Physicochem Eng Asp 1998. [DOI: 10.1016/s0927-7757(98)00669-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Electrokinetic characterization of a microporous non-commercial polysulfone membrane: phenomenological coefficients and transport parameters. Colloids Surf A Physicochem Eng Asp 1998. [DOI: 10.1016/s0927-7757(97)00298-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Benavente J, Jonsson G. Effect of adsorbed protein on the hydraulic permeability, membrane and streaming potential values measured across a microporous membrane. Colloids Surf A Physicochem Eng Asp 1998. [DOI: 10.1016/s0927-7757(97)00119-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Lucas D, Rabiller-Baudry M, Michel F, Chaufer B. Role of the physico-chemical environment on ultrafiltration of lysozyme with modified inorganic membrane. Colloids Surf A Physicochem Eng Asp 1998. [DOI: 10.1016/s0927-7757(97)00304-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Pastor R, Calvo J, Prádanos P, Hernández A. Surface charges and zeta potentials on polyethersulphone heteroporous membranes. J Memb Sci 1997. [DOI: 10.1016/s0376-7388(97)00186-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Benavente J, Jonsson G. Effect of Adsorption of Charged Macromolecules on Streaming and Membrane Potential Values Measured with a Microporous Polysulfone Membrane. SEP SCI TECHNOL 1997. [DOI: 10.1080/01496399708000729] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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A new method for determining transport numbers of charged membranes from convective diffusion experiments. J Electroanal Chem (Lausanne) 1994. [DOI: 10.1016/0022-0728(94)87062-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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