Effect of crosslinking on organic solvent nanofiltration performance of cellulose membranes

Konca, Kübra
Nanofiltration is a membrane process capable of separation of small molecules and multivalent ions due to their size and/or charge. NF is mainly used in aqueous applications. However, there are many processes that can take advantages of NF in molecules separation dissolved in organic solvents. Main challenge in Organic Solvent Nanofiltration is the limited number of membranes which can withstand a wide range solvents and have stable, predictable separation performance. Cellulose is an alternative polymer that can be used in OSN membranes as it is stable in many organic solvents due to its inter- and intra- molecular hydrogen bonds. Cellulose membranes were fabricated via phase inversion. Solutes used in tests are Bromothymol Blue (neutral,624 Da,=251.1cm3/mole), Cresol Red (neutral,382 Da,=140.1cm3/mole), Rose Bengal (anionic,1017 Da,=241.0cm3/mole) and Brilliant Blue R (anionic,826 Da,=421.3cm3/mole) and Crystal Violet (cationic,407 Da,=253.7cm3/mole). Membranes were crosslinked using two crosslinking agents: glutaraldehyde and 1,2,3,4-butanetetracarboxylic acid. Cellulose membranes was tested with five different solutes.Molecular size is a determining factor for separation of neutral dyes since BTB rejection is higher ratio than CR. BTB and CV rejections are quite close to each other while RB is retained much less than these dyes although molecular size of them are similar. GA-crosslinking did not change solvent permeance and solute rejection. After BTCA-crosslinking, CV rejection decreases slightly while RB rejection increases significantly. Amount of sorbed RB during filtration decreases significantly whereas sorbed CV increases, which may explain increased RB rejection, decreased CV rejection.


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Aslan, B; Turan, Raşit; Nur, O; Karlsteen, M; Willander, M (1999-12-02)
A Schottky type infrared detector fabricated on a p-type Si1-xGex substrate has a higher cut-off wavelength than one on a pure Si substrate because the barrier height of the Schottky junction on p-type Si1-xGex decreases with the Ge content and the induced strain in the Si1-xGex layer. We have studied the effect of the strain relaxation on the internal photoemission and I-V characteristics of a Pt/Si1-xGex Schottky junction with x=0.14. It is shown that the cut-off wavelength of the diode made on a strained...
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Sukma, Faqih Muhamad; Çulfaz Emecen, Pınar Zeynep; Department of Chemical Engineering (2016)
Cellulose is an alternative polymer that can be used in Organic Solvent Nanofiltration (OSN) where lack of chemically-stable membranes is a major problem. Cellulose, due to strong inter and intramolecular hydrogen bonding, is difficult to dissolve in many solvents, which is an advantage for OSN applications. Common solvent systems like Sodium Hydroxide/Carbon Disulfide (NaOH/CS2) or N-Methylmorpholine-N-oxide (NMMO) for cellulose solubilization are either toxic or unstable. Recent studies have shown that th...
BATTAL, T; BAC, N; Yılmaz, Levent (Informa UK Limited, 1995-01-01)
An emerging membrane morphology with future potential is mixed matrix membranes composed of two interpenetrating matrices of different materials. In this study, mixed matrix membranes of an amorphous glassy polymer(polyethersulfone) and hydrophilic zeolite (4A) were prepared. An elaborate membrane preparation technique that enables incorporation of high zeolite loading into the membrane was developed. Performance of membranes was tested by using a laboratory-scale gas separation apparatus. The permeation ra...
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İmir, Zeyne; Çulfaz Emecen, Pınar Zeynep; Department of Chemical Engineering (2019)
Cellulose, the most abundant polymer in nature, is an attractive membrane material. Hydroxyl groups in the polymer chain make it hydrophilic, which makes cellulose membranes fouling resistant. Intra and intermolecular hydrogen bonding due to these groups on the other hand gives cellulose solvent resistance which is an attractive property for membrane filtration in organic solvents. Although cellulose is insoluble in many solvents, ionic liquids dissolve cellulose so that cellulose membranes can be prepared ...
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Cytokinesis is the division of the cytoplasm and the plasma membrane into two. Nuclear division and cytokinesis take a relatively short time to happen in animal cells in which cytokinesis takes place by means of furrowing. Here we consider the cleavage of the animal cells only. Although the basic division mechanisms appear to be similar in all animal cells, the divisions that take place during early embryonic development, which are termed as cleavages, are not exactly the same as those that occur later. In ...
Citation Formats
K. Konca, “Effect of crosslinking on organic solvent nanofiltration performance of cellulose membranes,” M.S. - Master of Science, Middle East Technical University, 2018.