Controlling Cellulose Membrane Performance via Solvent Choice during Precursor Membrane Formation

Tekin, Fatma Seden
Çulfaz Emecen, Pınar Zeynep
Fabrication of cellulose membranes by alkaline hydrolysis of cellulose acetate (CA) membranes is a simple alternative method to preparing cellulose membranes via phase inversion from their ionic liquid solutions. In this study, three different solvent systems were used to fabricate cellulose acetate membranes by phase inversion, which are dimethyl sulfoxide and its mixtures with acetone and acetic acid. Acetone as cosolvent led to an asymmetric morphology with the densest selective layer, whereas acetic acid led to a loose, almost isotropic structure with high porosity and pore connectivity, also reflected in the pure water permeance and molecular weight cutoff (MWCO) of the CA membranes. Comparing the effects of these cosolvents on the phase inversion process, acetic acid decreased the solvent quality, increased nonsolvent-solvent interactions, and in total decreased the polymer solutions' stability against phase separation. The phase inversion rate when acetic acid was used as cosolvent was also markedly lower, which was attributed primarily to the solvent's much higher viscosity. After alkaline hydrolysis of the CA membranes, which converted them into cellulose membranes, the permeance and MWCO of large-pore, small-pore, and dense membranes changed in different directions. This was attributed to a changing membrane structure due to partial degradation of cellulose chains in an alkaline medium, which in turn can affect transport through both the pores and the membrane matrix.


Effect of solvent choice on cellulose acetate membrane fabrication by phase inversion and deacetylation by alkaline hydrolysis
Tekin, Fatma Seden; Çulfaz Emecen, Pınar Zeynep; Department of Chemical Engineering (2022-8)
In this study, the effect of solvent choice on cellulose acetate (CA) membrane morphology and performance was investigated to relate this to the thermodynamics and kinetics of phase inversion. Three different solvent systems were used, which are dimethyl sulfoxide (DMSO), the mixture of DMSO: acetone (DA) and DMSO: acetic acid (DHAc) in the ratio of 1:1. Water was used as non-solvent. Acetone and acetic acid were chosen due to their similar solvent quality for cellulose acetate based on Hansen solubility pa...
Cellulose-based membranes via phase inversion using [EMIM]OAc-DMSO mixtures as solvent
Durmaz, Elif Nur; Çulfaz Emecen, Pınar Zeynep (2018-03-16)
Cellulose and cellulose acetate membranes were fabricated by phase inversion from their solutions in 1-ethyl-3-methylimidazolium acetate ([EMIM] OAc), or its mixture with dimethyl sulfoxide (DMSO). Inclusion of DMSO in the solution decreased crystallinity and rejection for both polymers. When cellulose solutions were coagulated in ethanol crystallinity and rejections were lower, and cellulose acetate membranes coagulated in ethanol had a loose, macroporous morphology, which was attributed to the poor nonsol...
Effect of carboxylic acid crosslinking of cellulose membranes on nanofiltration performance in ethanol and dimethylsulfoxide
Konca, Kubra; Çulfaz Emecen, Pınar Zeynep (2019-10-01)
Cellulose membranes were fabricated via phase inversion using 1-ethyl-3-methylimidazolium acetate as solvent and acetone as volatile cosolvent. 1,2,3,4-butanetetracarboxylic acid was used to partially crosslink the hydroxyl groups of cellulose, thereby changing mechanical properties of the membranes and the interactions with solvents, ethanol and dimethyl sulfoxide, and solutes. Rejection of dyes of similar size, Bromothymol Blue, Rose Bengal and Crystal Violet were shown to correlate inversely with sorptio...
Cellulose membranes for organic solvent nanofiltration
Sukma, F. M.; Çulfaz Emecen, Pınar Zeynep (2018-01-01)
Cellulose membranes were fabricated by phase inversion from solutions of cellulose in 1-ethyl-3-methylimidazolium acetate ([EMIM] OAc) as solvent and acetone as volatile cosolvent. The rejection of Bromothymol Blue ( 624 Da) in ethanol increased and the permeance decreased by increasing the cellulose concentration in the solution prior to coagulation, either by having more cellulose in the starting solution or by evaporating the volatile cosolvent. Drying the membranes after coagulation further increased th...
Effect of preparation parameters on the performance of conductive composite gas separation membranes
Gulsen, D; Hacarloglu, P; Toppare, Levent Kamil; Yılmaz, Levent (2001-02-15)
Mixed matrix composite membranes of a conducting polymer, polypyrrole (PPy), and an insulating polymer, polybisphenol-A-carbonate (PC) were prepared by a combined in-situ polymerization and solvent evaporation. Mixed matrix composite membranes were synthesized to combine the good gas transport properties of conductive polymer, PPy, with good mechanical properties of PC.
Citation Formats
F. S. Tekin and P. Z. Çulfaz Emecen, “Controlling Cellulose Membrane Performance via Solvent Choice during Precursor Membrane Formation,” ACS APPLIED POLYMER MATERIALS, vol. 5, no. 3, pp. 2185–2194, 2023, Accessed: 00, 2023. [Online]. Available: