Surface charge characterization of nanofiltration membranes by potentiometric titrations and electrophoresis: Functionality vs. zeta potential

We present an experimental study on the electrofluidic transistor in this paper. A novel and easy way to integrate the transistor into a microchannel is developed. The performances of the insulating layer, especially the leakage current under gate voltage, are carefully characterized. The change of surface charge on silica surface by gate polarization is measured, however, by measuring the streaming current, the gating effect on zeta potential has not been observed. This result should imply new assumption in the understanding of the charge regulation in the electrical double layer under gate polarization.

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Charge characteristics (surface charge vs. zeta potential) of membrane surfaces to assess the salt rejection behavior of nanofiltration membranes

Separation and Purification Technology ◽

10.1016/j.seppur.2020.117026 ◽

2020 ◽

Vol 247 ◽

pp. 117026

Author(s):

Byung-Moon Jun ◽

Jaeweon Cho ◽

Am Jang ◽

Kangmin Chon ◽

Paul Westerhoff ◽

...

Keyword(s):

Zeta Potential ◽

Surface Charge ◽

Nanofiltration Membranes ◽

Salt Rejection ◽

Membrane Surfaces

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Characterization of surface charge and zeta potential of colloidal silica prepared by various methods

Korean Journal of Chemical Engineering ◽

10.1007/s11814-014-0112-5 ◽

2014 ◽

Vol 31 (11) ◽

pp. 2088-2093 ◽

Cited By ~ 6

Author(s):

Gyeong Sook Cho ◽

Dong-Hyun Lee ◽

Hyung Mi Lim ◽

Seung-Ho Lee ◽

Chongyoup Kim ◽

...

Keyword(s):

Zeta Potential ◽

Surface Charge ◽

Colloidal Silica

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Nanofiltration membranes for salt and dye filtration: effect of membrane properties on performances

Water Science & Technology ◽

10.2166/wst.2021.125 ◽

2021 ◽

Author(s):

Meltem Ağtaş ◽

Türkan Ormancı-Acar ◽

Başak Keskin ◽

Türker Türken ◽

İsmail Koyuncu

Keyword(s):

Contact Angle ◽

Zeta Potential ◽

Mechanical Strength ◽

Membrane Properties ◽

Nanofiltration Membranes ◽

Data Set ◽

Membrane Performance ◽

Different Temperatures ◽

Dye Solutions

Abstract In this study, commercial nanofiltration membranes (Toray, NF 270, Desal 5 L) were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, optical profilometry, contact angle, mechanical strength and zeta potential measurements. Filtration performance tests were conducted with distilled water, MgSO4 solution and synthetic dye solutions, respectively. Among three commercial membranes, the Toray membrane was thought to be better choice. Additional experiments were carried out for a more detailed characterization of the selected membrane. Therefore, firstly, flux and removal efficiency was monitored by using dye solutions at different pH values, and then experiments were carried out to observe the effect of different temperatures. Also, another filtration test with NaCl solution was performed for the Toray membrane. As the main purpose of this study, we aimed to establish a significant correlation between the structural properties of membranes and their performances. In light of the results obtained, it was observed that the contact angle, mechanical strength and surface roughness values of the membrane significantly affected the membrane performance. It was concluded that the most important parameter in dye removal was the zeta potential. As a result of this work, a data set of commercial membranes was created and is available to all membrane users.

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Physicochemical Characterization of Natural Wollastonite and Calcite

Minerals ◽

10.3390/min10030228 ◽

2020 ◽

Vol 10 (3) ◽

pp. 228 ◽

Cited By ~ 1

Author(s):

Murat Olgaç Kangal ◽

Gülay Bulut ◽

Onur Guven

Keyword(s):

Zeta Potential ◽

Surface Charge ◽

Chemical Stability ◽

Raw Materials ◽

Physicochemical Characterization ◽

Contact Angles ◽

Thermal Resistivity ◽

Bright Color ◽

High Alkalinity

Wollastonite and calcite minerals are significant raw materials and are extensively used due to their unique properties. Wollastonite is used in plastics, paint, ceramics, paper, resins, and in construction as a substitution for asbestos due to its chemical stability, thermal resistivity, needle-like shape, and brightness. Calcite is one of the most used raw materials because of its low hardness, high alkalinity, sorptive properties, white and bright color. Wollastonite and calcite are two minerals found together in nature. The most common method used for separating these two minerals is flotation. In this study, the surface properties of pure mineral samples were investigated. The pH profiles of both minerals were obtained by measuring the surface charge of particles followed by the measurement of the zeta potential in different collector concentrations. The wettability of minerals was examined by measuring their contact angles.

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Incorporation of micro/nanoparticles of PCL with essential oil of Cymbopogon nardus in bacterial cellulose

International Journal of Advances in Medical Biotechnology - IJAMB ◽

10.25061/2595-3931/ijamb/2018.v1i2.18 ◽

2018 ◽

Vol 1 (2) ◽

pp. 37

Author(s):

Aline Krindges ◽

Vanusca Dalosto Jahno ◽

Fernando Morisso

Keyword(s):

Particle Size ◽

Particulate Matter ◽

Essential Oil ◽

Zeta Potential ◽

Bacterial Cellulose ◽

Culture Medium ◽

Static Culture ◽

Cymbopogon Nardus ◽

Cellulose Membranes

Incorporation studies of particles in different substrates with herbal assets growing. The objective of this work was the preparation and characterization of micro/nanoparticles containing cymbopogon nardus essential oil; and the incorporation of them on bacterial cellulose. For the development of the membranes was used the static culture medium and for the preparation of micro/nanoparticles was used the nanoprecipitation methodology. The incorporation of micro/nanoparticles was performed on samples of bacterial cellulose in wet and dry form. For the characterization of micro/nanoparticles were carried out analysis of SEM, zeta potential and particle size. For the verification of the incorporation of particulate matter in cellulose, analyses were conducted of SEM and FTIR. The results showed that it is possible the production and incorporation of micro/nanoparticles containing essential oil in bacterial cellulose membranes in wet form with ethanol.

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Dispersive evaluation and surface chemistry of advanced, multifunctional silica/lignin hybrid biomaterials

Open Chemistry ◽

10.2478/s11532-013-0322-4 ◽

2013 ◽

Vol 11 (11) ◽

pp. 1860-1873 ◽

Cited By ~ 6

Author(s):

Magdalena Nowacka ◽

Łukasz Klapiszewski ◽

Małgorzata Norman ◽

Teofil Jesionowski

Keyword(s):

Zeta Potential ◽

Surface Charge ◽

Electrochemical Sensors ◽

Relevant Information ◽

Structural Features ◽

Kraft Lignin ◽

Morphological Properties ◽

Wide Range ◽

Hybrid Biomaterials

AbstractAdvanced silica/lignin hybrid biomaterials were obtained using hydrated or fumed silicas (Aerosil®200) and Kraft lignin as precursors, which is a cheap and biodegradable natural polymer. To extend the possible range of applications, the silicas were first modified with N-2-(aminoethyl)-3-aminopropyltrimethoxsysilane, and then with Kraft lignin, which had been oxidized with sodium periodate. The SiO2/lignin hybrids and precursors were characterised by means of determination of their physicochemical and dispersive-morphological properties. The effectiveness of silica binding to lignin was verified by FT-IR spectroscopy. The zeta potential value provides relevant information regarding interactions between colloid particles. Measurement of the zeta potential values enabled an indirect assessment of stability for the studied hybrid systems. Determination of zeta potential and density of surface charge also permitted the quantitative analysis of changes in surface charge, and indirectly confirmed the effectiveness of the proposed method for synthesis of SiO2/lignin hybrid materials. A particularly attractive feature for practical use is their stability, especially electrokinetic stability. It is expected that silica/lignin hybrids will find a wide range of applications (polymer fillers, biosorbents, electrochemical sensors), as they combine the unique properties of silica with the specific structural features of lignin. This makes these hybrids biomaterials advanced and multifunctional.

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