Comprehensive Analysis on Anomalous Phenomenon of Ethanol-Soluble PVB Membrane for Ethanol Recovery via Pervaporation

Poly(vinyl butyral) is selected as a promising ethanol-permselective membrane based the solubility parameter theory, however it exhibits anomalous water perm-selectivity in practical pervaporation process. Comprehensive analysis based on experimental and theoretical methods were carried out to explore the inherent mechanism of the anomalous performance. Firstly, sum frequency generation vibrational spectra and contact angle were developed to quantify the surface reconstruction of membrane in air and ethanol, which indicated that hydrophilic hydroxyl tended to expose on membrane surface with ethanol thus improved the membrane affinity to water. Meanwhile, swelling behaviors proved more water would accumulate in the ethanol swollen membrane. Furthermore, theoretical analysis in terms of sorption and diffusion process, based on the UNIFAC-FV model and Fujita free volume theory, confirmed the mechanism of anomalous phenomenon of poly(vinyl butyral) membrane. The comprehensive investigation was expected to provide insights into the basic separation mechanism of pervaporation process.

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Lasalocid Acid Antibiotic at a Membrane Surface Probed by Sum Frequency Generation Spectroscopy

Langmuir ◽

10.1021/acs.langmuir.9b03752 ◽

2020 ◽

Vol 36 (12) ◽

pp. 3184-3192 ◽

Cited By ~ 1

Author(s):

Thaddeus W. Golbek ◽

Lars Schmüser ◽

Mette H. Rasmussen ◽

Thomas B. Poulsen ◽

Tobias Weidner

Keyword(s):

Membrane Surface ◽

Sum Frequency Generation ◽

Sum Frequency ◽

Sum Frequency Generation Spectroscopy ◽

Frequency Generation

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Sorption and diffusion measurements in ternary polymer–solvent–solvent systems by means of a magnetic suspension balance—Experimental methods and correlations with a modified Flory–Huggins and free-volume theory

Chemical Engineering Science ◽

10.1016/j.ces.2006.12.062 ◽

2007 ◽

Vol 62 (8) ◽

pp. 2254-2266 ◽

Cited By ~ 35

Author(s):

Wilhelm Schabel ◽

Philip Scharfer ◽

Matthias Kind ◽

Ioan Mamaliga

Keyword(s):

Free Volume ◽

Experimental Methods ◽

Magnetic Suspension ◽

Free Volume Theory ◽

Magnetic Suspension Balance ◽

Solvent Systems ◽

Ternary Polymer ◽

And Diffusion ◽

Solvent Solvent ◽

Polymer Solvent

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Pulsed and Steady Field Gradient NMR Diffusion Measurements in Polymers

Rubber Chemistry and Technology ◽

10.5254/1.3536078 ◽

1985 ◽

Vol 58 (3) ◽

pp. 527-560 ◽

Cited By ~ 33

Author(s):

Ernst D. von Meerwall

Keyword(s):

Spin Echo ◽

Concentrated Solutions ◽

Free Volume Theory ◽

Polymer Systems ◽

Polymer Molecules ◽

Self Diffusion ◽

Semidilute Solutions ◽

Nmr Diffusion ◽

Nmr Methods ◽

And Diffusion

Abstract Some twenty years after the development of the steady and pulsed gradient spin-echo NMR methods of measuring self-diffusion, these techniques are now maturing and experiencing a surge of interest, much of it concentrated on polymer systems. The methods are briefly reviewed here, together with the most important results in polymers, with particular concentration on work described within the last few years. The research is divisible into three categories: diffusion of diluent and penetrant molecules in rubbery high polymers, diffusion of polymer molecules in dilute and semidilute solutions with liquid solvents, and diffusion of macromolecules dissolved in concentrated solutions or melts of equivalent or different polymers of arbitrary molecular weight. The review includes the main theoretical interpretations of the experiments, particularly the free-volume theory in its various forms and power-law behaviors postulated by recent refinements of tube/reptation and scaling theory. This article represents an updated elaboration of an earlier review.

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Modification of ion-exchange membrane surface by plasma process. Part 2. Monovalent cation permselective membrane from perfluorosulfonate cation exchange membrane

Journal of Membrane Science ◽

10.1016/s0376-7388(00)82077-3 ◽

1990 ◽

Vol 54 (1-2) ◽

pp. 163-174 ◽

Cited By ~ 14

Author(s):

Zempachi Ogumi ◽

Yoshiharu Uchimoto ◽

Masanori Tsujikawa ◽

Kazuaki Yasuda ◽

Zen-Ichiro Takehara

Keyword(s):

Ion Exchange ◽

Cation Exchange ◽

Membrane Surface ◽

Monovalent Cation ◽

Cation Exchange Membrane ◽

Ion Exchange Membrane ◽

Plasma Process ◽

Permselective Membrane ◽

Exchange Membrane

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Molecule transfer mechanism in 2D heterostructured lamellar membranes: The effects of dissolution and diffusion

10.22541/au.162834995.52283705/v1 ◽

2021 ◽

Author(s):

Chongchong Chen ◽

Xiaoli Wu ◽

Jie Zhang ◽

Jingjing Chen ◽

Xulin Cui ◽

...

Keyword(s):

Diffusion Processes ◽

Cyanuric Acid ◽

Membrane Surface ◽

Transfer Mechanism ◽

Two Dimensional ◽

Polar Solvents ◽

Nonpolar Solvents ◽

Self Assembling ◽

Resistance Transfer ◽

And Diffusion

Two-dimensional (2D) lamellar membranes are promising for efficient molecule transfer, while the underlying molecule transfer mechanism is rarely elucidated. Herein, heterostructured nanosheets are prepared by self-assembling small-sized hydrophilic cyanuric acid melamine (CMN) and hydrophobic g-C3N4 nanosheets. The resultant lamellar membranes show comparable affinity to both polar and nonpolar solvents, allowing them to dissolve on membrane surface and diffuse through membrane channels. Permeance results demonstrate that the transfer of polar solvents is controlled by dissolution and diffusion processes, while that of nonpolar solvents is governed by dissolution process. And the corresponding equations are established. Importantly, polar solvents are induced to form ordered arrangement in hydrophilic nanodomains and then maintain this state in hydrophobic nanodomains, affording low-resistance transfer thus high permeance: 1025 L m-2 h-1 bar-1 for acetonitrile. In contrast, nonpolar solvents with disordered arrangement acquire lower permeance than that of polar ones, but with comparable diffusion ability in these membranes.

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U.S. Counties' Efforts and Results

Handbook of Research on Strategies for Local E-Government Adoption and Implementation ◽

10.4018/978-1-60566-282-4.ch019 ◽

2009 ◽

pp. 367-389

Author(s):

Zhenyu Huang

Keyword(s):

Regression Analysis ◽

Socioeconomic Factors ◽

Web Sites ◽

Comprehensive Analysis ◽

Government Officials ◽

Analysis Methodology ◽

Government Web Sites ◽

Comprehensive Picture ◽

Adoption And Diffusion ◽

And Diffusion

This chapter presents a comprehensive analysis of the 3,099 U.S. counties’ adoption and diffusion of e-government and the functions provided by their Web sites. By using content analysis methodology, the services and functions of U.S. county e-government Web sites are investigated and analyzed. The research finds that U.S. counties’ e-government adoption is highly associated with socioeconomic factors; in addition, the functionalities of local e-government Web sites are significantly related to multiple socioeconomic factors according to the regression analysis. The chapter provides government officials and practitioners a comprehensive picture of U.S. local e-government practice. It sheds light on e-government research by bringing in a valuable research instrument and comprehensive analysis of e-government adoption and diffusion.

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