Synthesis and characterization of polyacrylamide‐grafted sodium alginate copolymeric membranes and their use in pervaporation separation of water and tetrahydrofuran mixtures

Abstract

Polyacrylamide-grafted sodium alginate (PAAm-g-Na-Alg) copolymeric membranes have been prepared, characterized, and used in the pervaporation separation of 10-80 mass % water-containing tetrahydrofuran mixtures. Totally three membranes were prepared: (1) neat Na-Alg with 10 mass % of polyethylene glycol (PEG) and 5 mass % of polyvinyl alcohol (PVA), (2) 46 % grafted PAAm-g-Na-Alg membrane containing 10 mass % of PEG and 5 mass % of PVA, and (3) 93 % grafted PAAm-g-Na-Alg membrane containing 10 mass % of PEG and 5 mass % of PVA. Using the transport data, important parameters like permeation flux, selectivity, pervaporation separation index, swelling index, and diffusion coefficient have been calculated at 30°C. Diffusion coefficients were also calculated from sorption gravimetric data of water-tetrahydrofuran mixtures using Fick's equation. Arrhenius activation parameters for the transport processes were calculated for 10 mass % of water in the feed mixture using flux and diffusion data obtained at 30, 35, and 40°C. The separation selectivity of the membranes ranged between 216 and 591. The highest permeation flux of 0.677 kg/m 2 h was observed for 93% grafted membrane at 80 mass % of water in the feed mixture.

Hydrophilically surface-modified and crosslinked polybenzimidazole membranes for pervaporation dehydration on tetrahydrofuran aqueous solutions

“…To improve the separation performance, Oikawa et al prepared pyridine-containing poly(acylhydrazone)s which showed high water selectivity in pervaporation dehydration on THF/water mixtures [31]. Kurkuri et al grafted polyacrylamide to sodium alginate to increase the stability of the corresponding membranes used for dehydration pervaporation on THF aqueous solutions [32]. The separation performance of the membranes was attractive, but preparation of the polymers involved complicated synthesis route.…”

Novel polyion complex films from chitosan and quarternized poly(4‐vinyl‐N‐carboxymethylpyridine) containing zwitterion structure units

“…Chitosan, 1 sodium alginate, poly(acrylic acid) (PAA)/polysulfone (PSF) composite, poly(vinylidene fluoride)/poly(styrene sulfonate) composite, polypyrrolidone/poly(methacrylic acid) composite, sulfonated cellulose/poly(dimethylammmonium chloride) ion complex, PAA/polymer with quaternary ammonium groups on the main chain ion complex, j-caraginan/poly [1,3-bis(4-alkylpyridium)propane bromide] ion complex membranes, 2 ionomeric membranes of perfluorosulfonic acid (PFSA) polymer, 3 polydimethylsiloxane-coated polyetherimide membranes, 4 poly(vinyl alcohol)-poly(N-vinyl pyrrolidone) blends, 5 sodium alginate, poly(vinyl alcohol) blend membranes, 6 and so on, which have been used for the dehydration from the organic solvents and have shown high water-permselectivity. In addition, the graft-and block-copolymerization membranes have also shown high water-permselectivity such as poly(vinyl alcohol) (PVA)-g-(nylon4), polycarbonateg-vinylpridine, PSF-g-acrylamido (AAm), PVA-g-(NIso-propylacrylamido), poly(butyl terephthalate)-block-poly(ethylene oxide), 2 porous substrates of high density polyethylene-g-vinyl monomers, 7 sodium alginate-g-polyacrylamide, 8,9 polyacrylonitrile-g-poly-(vinyl alcohol), 10 and so on. Among the membrane materials, the hydrophilic polysaccharide polymers such as chitosan have gained special interest because they have shown the highest flux and separation factors of any hydrophilic materials tested for the pervaporation dehydration.…”

Characterization and performance evaluations of sodium zeolite‐Y filled chitosan polymeric membrane: Effect of sodium zeolite‐Y concentration

“…6 It is also applied in the dehydration of the following: alcohol using a surface resintering expanded poly(tetrafluoroethylene), 7 butanol using an asymmetric sulfonated polystyrene sulfonated poly(ether sulfone), 8 phenol using a polyamide membrane, 9 isopropanol using a sodium alginate (SA)/polyacrylamide blend membrane, 10 isopropanol using an polyacrylonitrile/ alginate membrane, 11 isopropanol using a sodium zeolite-Y (NaY zeolite) incorporated SA membrane, 12 light oil using a PVA/poly(acrylic acid-co-maleic acid) membrane, 13 toluene using a composite membrane, 14 hydrazine using an ethylcellulose membrane, 15 and dehydration of tetrahydrofuran using a polyacrylamide-grafted SA copolymeric membrane. 16 Pervaporation is also used in the removal of small quantities of volatile organic solutes or organic solvents from water using hydrophobic membranes.…”