Preparation and characterization of PVA membrane modified by water‐soluble hyperbranched polyester (WHBP) for the dehydration of <i>n</i>‐butanol

Zhang, Qian-Zhi; Li, Bingbing; Sun, De; Zhang, Lijun; Li, Dayong; Yang, Ping

doi:10.1002/app.43533

Cited by 10 publications

(4 citation statements)

References 34 publications

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“…The significant water uptake of pristine PVA membrane was caused by its highly hydrophilic behavior . The hydrophilicity was suppressed by TEOS cross‐linking agent , but the diffusion coefficient consequently decreased (Figure ).…”

Section: Resultsmentioning

confidence: 99%

The determination of effective diffusion coefficient from the electrochemical impedance spectra of composite poly (vinyl alcohol) membranes

Martı́n

Remiš

Gholami

2019

Env Prog and Sustain Energy

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This study presents the effect of swelling on effective diffusion coefficient of the composite poly(vinyl alcohol) (PVA) membranes through electrochemical impedance spectroscopy. The PVA based membranes were cross‐linked by sulfosuccinic acid (SSA) or tetraethylorthosilicate (TEOS) to improve the ionic conductivity and suppress the swelling. The impedance spectra of the synthesized membranes were recorded and then fitted using Randles circuit. The values of the Warburg element were analyzed and the effective diffusion coefficient was calculated for membranes in dry or wet state. Obtained values were compared with those of the Nafion NR 212 and pure PVA. A significant dependency of effective diffusion coefficient on dimension change caused by swelling was measured. In case of SSA cross‐linking, an improvement of ionic conductivity by chemical modification was observed. However, the highly hydrophilic behavior of PVA SSA samples is limiting further utilization of membrane in applications such as methanol fuel cells. To improve the stability of membrane in the wet environment, the composite PVA SSA TEOS membrane was prepared. © 2019 American Institute of Chemical Engineers Environ Prog, 38:e13146, 2019

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Section: Resultsmentioning

confidence: 99%

The determination of effective diffusion coefficient from the electrochemical impedance spectra of composite poly (vinyl alcohol) membranes

Martı́n

Remiš

Gholami

2019

Env Prog and Sustain Energy

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“…In the present case, the modification of PVA with ZSM-5 has acknowledged in depreciating its swelling behavior in the water-based application. Comprehensive articles have been reported in this regard [45][46][47][48]. The WU and area swelling results are assessed as given in Figure 6.…”

Section: Water Uptake (Wu) and Area Swellingmentioning

confidence: 99%

PVA-Based Mixed Matrix Membranes Comprising ZSM-5 for Cations Separation

et al. 2020

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The traditional ion-exchange membranes face the trade-off effect between the ion flux and perm-selectivity, which limits their application for selective ion separation. Herein, we amalgamated various amounts of the ZSM-5 with the polyvinyl alcohol as ions transport pathways to improve the permeability of monovalent cations and exclusively reject the divalent cations. The highest contents of ZSM-5 in the mixed matrix membranes (MMMs) can be extended up to 60 wt% while the MMMs with optimized content (50 wt%) achieved high perm-selectivity of 34.4 and 3.7 for H+/Zn2+ and Li+/Mg2+ systems, respectively. The obtained results are high in comparison with the commercial CSO membrane. The presence of cationic exchange sites in the ZSM-5 initiated the fast transport of proton, while the microporous crystalline morphology restricted the active transport of larger hydrated cations from the solutions. Moreover, the participating sites and porosity of ZSM-5 granted continuous channels for ions electromigration in order to give high limiting current density to the MMMs. The SEM analysis further exhibited that using ZSM-5 as conventional fillers, gave a uniform and homogenous formation to the membranes. However, the optimized amount of fillers and the assortment of a proper dispersion phase are two critical aspects and must be considered to avoid defects and agglomeration of these enhancers during the formation of membranes.

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“…So, the preparation of hydrophilic, highly permeable, water-insoluble PVA membranes is an important challenge. Crosslinking process is commonly used to improve their physical stability in aqueous systems [4,[9][10][11][12]. However, crosslinking process reduces the hydrophilicity of PVA membranes as well as their permeability.…”

Section: Introductionmentioning

confidence: 99%