Dehydration of tetrahydrofuran by pervaporation using crosslinked PVA/PEI blend membranes

Abstract

Dense blend membranes were prepared by blending hydrophilic polymers poly(vinyl alcohol) (PVA) and poly(ethyleneimine) (PEI), which were then crosslinked by glutaraldehyde (GA) in a mixture of solvents under the catalysis of hydrochloric acid (HCl) for the dehydration of tetrahydrofuran (THF) by pervaporation. The effect of experimental parameters such as feed water concentration, permeate pressure, and membrane thicknesses on permeate parameters, i.e., flux and selectivity were determined with feed water concentration less than 40 wt %. The membranes were found to have good potential for breaking the azeotrope of 94 wt % THF with a flux of 1.072 and 0.376 kg/m 2 h for plane PVA/PEI and crosslinked PVA/PEI blend membrane, which exhibited high selectivity of 156 and 579 respectively. Selectivity was found to improve with decreasing feed water concentration and increasing membrane thickness, whereas flux decreased correspondingly. High permeate pressure causes a reduction in both flux and selectivity. These effects were clearly elucidated with the aid of the known relationship among plasticization effect, degree of swelling, permeate pressure, and feed water concentration. These blend membranes were also subjected to sorption studies to evaluate the extent of interaction and degree of swelling in pure as well as binary feed mixtures. Further ion exchange capacity studies were carried out for all the crosslinked and uncrosslinked membranes to determine the total number of interacting groups present in the membranes.

Solution Viscosity‐Mediated Structural Control of Nanofibrous Sponge for RNA Separation and Purification

“…[ 28 ] Furthermore, a typical X‐ray photoelectron spectroscopy (XPS) survey spectrum of the NFSs was obtained to further confirm the above‐mentioned reactions shown in Figure 2b. The newly formed bonds of COC and CN bonds could be confirmed from C 1s (Figure 2c), O 1s (Figure 2d), and N 1s (Figure 2e) spectra, indicating the successful crosslinking of GA with PVA‐ co ‐PE, CS, and PEI [ 29 ] (XPS spectra of PVA‐ co ‐PE and CS are shown in Figures S15 and S16, Supporting Information). The peak at 398.6 eV corresponds to N 1s in CN group of the crosslinked products of GA with CS and PEI.…”

An EVOH nanofibrous sterile membrane with a robust and antifouling surface for high-performance sterile filtration via glutaraldehyde crosslinking and a plasma-assisted process

“…Thus, NFM-CP formed a unique porous structure with a loose surface and dense interior, which is capable of being a potential material for high performance sterile filtration. 23,24 The reaction equation of EVOH and GA 25 is shown in Fig. 2a and the surface chemical structure changes of NFM-CP were analyzed by FT-IR spectroscopy and XPS spectroscopy.…”

Preparation of hydrogels composed of poly(vinyl alcohol) and polyethyleneimine and their electrical response

“…As a similar result, Rao et al reported that the crosslinked PVA/PEI membrane using glutaraldehyde also showed the lower sorption in comparison with the non-cross-linked PVA/PEI membrane because of forming the compact structure after crosslinking. 28 …”