scholarly journals Bipolar Membrane and Water Splitting in Electrodialysis

2021 ◽  
Author(s):  
Ireneusz Miesiac ◽  
Beata Rukowicz
Keyword(s):  
Current Flow ◽  
Electrode Reaction ◽  
Dissociation Rate ◽  
Water Dissociation ◽  
Bipolar Membrane ◽  
Water Conductivity ◽  
Electron Hole ◽  
Bipolar Membranes ◽  
Side Process ◽  
Mobility Of Ions

AbstractThe traditional view of the conductivity of electrolytes is based on the mobility of ions in an electric field. A new concept of water conductivity introduces an electron–hole mechanism known from semiconductor theory. The electrolyte ions in the hydrogen bond network of water imitate the structure of a doped silicon lattice. The source of the current carriers is the electrode reaction generating H+ and OH− ions. The continuity of current flow is provided through the electron–hole mechanism, and the movement of electrolyte ions is only a side process. Bipolar membrane in the semiconductor approach is an electrochemical diode forward biased. Generation of large amounts of H+ and OH− has to be considered as a result of current flow and does not require any increase in the water dissociation rate. Bipolar membranes are essential in electrodialysis stacks for the recovery of acids and bases by salt splitting. Graphic Abstract

Bipolar membrane polarization behavior with systematically varied interfacial areas in the junction region

2021 ◽  
Author(s):  
Subarna Kole ◽  
Gokul Venugopalan ◽  
Deepra Bhattacharya ◽  
Le Zhang ◽  
John Cheng ◽  
...  
Keyword(s):  
Electric Field ◽  
Water Dissociation ◽  
Bipolar Membrane ◽  
Junction Region ◽  
Bipolar Membranes ◽  
Membrane Polarization ◽  
Interfacial Areas ◽  
Left Image ◽  
The Right ◽  
The Relationship

Left image is the relationship for the overpotential for water dissociation as a function of bipolar junction electric field whereas the right image presents micrographs and the procedure to make bipolar membranes with micropatterned interfaces.

Effect of added salt and increase in ionic strength on skim milk electroacidification performances

2001 ◽  
Vol 68 (2) ◽  
pp. 237-250 ◽  
Author(s):  
LAURENT BAZINET ◽  
DENIS IPPERSIEL ◽  
CHRISTINE GENDRON ◽  
BEHZAD MAHDAVI ◽  
JEAN AMIOT ◽  
...  
Keyword(s):  
Ionic Strength ◽  
Protein Profile ◽  
Skim Milk ◽  
Operation Time ◽  
Water Dissociation ◽  
Bipolar Membrane ◽  
Cathode Voltage ◽  
Experimental Conditions ◽  
Bipolar Membranes ◽  
Added Salt

Bipolar-membrane electroacidification (BMEA) technology, which uses the property of bipolar membranes to split water and the demineralization action of cation-exchange membranes (CEM), was tested for the production of acid casein. BMEA has numerous advantages in comparison with conventional isoelectric precipitation processes of proteins used in the dairy industry. BMEA uses electricity to generate the desired ionic species to acidify the treated solutions. The process can be precisely controlled, as electro-acidification rate is regulated by the effective current density in the cell. Water dissociation at the bipolar membrane interface is continuous and avoids local excess of acid. In-situ generation of dangerous chemicals (acids and bases) reduces the risks associated with the handling, transportation, use and elimination of these products. The aim of this study was to evaluate the performance of BMEA in different conditions of added ionic strength (μadded = 0, 0·25, 0·5 and 1·0 M) and added salt (CaCl2, NaCl and KCl).The combination of KCl and μadded = 0·5 M gave the best results with a 45% decrease in energy consumption. The increased energy efficiency was the result of a decrease in the anode/cathode voltage difference. This was due to an increase of conductivity, produced by addition of salt, necessary to compensate for the lack of sufficiently mobile ions in the skim milk. However, the addition of salts, irrespective of type or ionic strength, increased the required operation time. The protein profile of isolates were similar under all experimental conditions, except at 1·0 M-CaCl2.

scholarly journals Low-waste fermentation-derived organic acid production by bipolar membrane electrodialysis—an overview

2021 ◽  
Author(s):  
Éva Hülber-Beyer ◽  
Katalin Bélafi-Bakó ◽  
Nándor Nemestóthy
Keyword(s):  
Organic Acid ◽  
Acid Production ◽  
Free Acid ◽  
Raw Materials ◽  
Fermentation Broth ◽  
Water Dissociation ◽  
Bipolar Membrane ◽  
Organic Acid Production ◽  
Bipolar Membranes ◽  
Bipolar Membrane Electrodialysis

AbstractOrganic acids, e.g, citric acid, fumaric acid, lactic acid, malic acid, pyruvic acid and succinic acid, have important role in the food industry and are potential raw materials for the sustainable chemical industry. Their fermentative production based on renewable raw materials requires innovatively designed downstream processing to maintain low environmental impact and resource efficiency throughout the production process. The application of bipolar membranes offers clean and effective way to generate hydrogen ions required for free acid production from its salt. The water dissociation reaction inside the bipolar membrane triggered by electric field plays key role in providing hydrogen ion for the replacement of the cations in organic acid salts. Combined with monopolar ion-exchange membranes in a bipolar membrane electrodialysis process, material flow can be separated beside the product stream into additional reusable streams, thus minimizing the waste generation. This paper focuses on bipolar membrane electrodialysis applied for organic acid recovery from fermentation broth.

Electrodialysis Pump Based on Enhanced Water Dissociation of Bipolar Membrane

2020 ◽  
Vol 92 (9) ◽  
pp. 6263-6268 ◽  
Author(s):  
Yue Sun ◽  
Shiyuan Lin ◽  
Feifang Zhang ◽  
Bingcheng Yang
Keyword(s):  
Water Dissociation ◽  
Bipolar Membrane

ERRATA: PHOTOLUMINESCENCE PROPERTIES AND LOCAL STRUCTURE OF POLYMER-LIKE a-C:H FILMS

2000 ◽  
Vol 14 (16) ◽  
pp. 1701-1717 ◽  
Author(s):  
C. GODET ◽  
T. HEITZ ◽  
B. DRAVILLON ◽  
J. E. BOURÉE
Keyword(s):  
Local Structure ◽  
Carbon Films ◽  
Dissociation Rate ◽  
Photoluminescence Properties ◽  
Elastic Recoil ◽  
Electron Hole ◽  
Elastic Recoil Detection ◽  
Bonded Materials ◽  
Infrared Ellipsometry

In order to understand better the electronic properties of π-bonded materials, some optical and photoluminescence properties of amorphous carbon films have been investigated as a function of film density (0.9 to 1.7 g·cm-3). This study gives an overview of the radiative recombination properties in relation with local structure characterizations (in situ infrared ellipsometry and Raman spectroscopies) for a series of dual-plasma deposited polymer-like a-C:H films. Medium range topology has consequences in the hyperconjugation effects seen on infrared bands, as well as in optical and resonant Raman characteristics. Photoluminescence (PL) excitation spectroscopy reveals resonance features which are attributed to exciton-like electron-hole pairs in close Coulomb interaction. The PL efficiency shows a sharp quenching for densities above 1.3 g·cm-3 where a clear transition also occurs in the Raman "fingerprint". In addition, quantitative analysis of IR ellipsometry and Elastic Recoil Detection give evidence of a strong decrease of both the effective dynamical charge e*(C-H) and the bandwidth of sp3 C-H vibrations; this is interpreted as being a result of the increase of local strains in the carbon skeleton, meaning that matrix distortions already appear at H content values as high as 46 H at.% due to film densification. An expected consequence is the mixing between π and σ molecular orbitals and the enhancement of the dissociation rate of confined electron-hole pairs. PL quenching would thus result from both a decrease of exciton confinement and an increase of the density of accessible nonradiative centers.

PHOTOLUMINESCENE PROPERTIES AND LOCAL STRUCTURE OF POLYMER-LIKE A-C:H FILMS

2000 ◽  
Vol 14 (02n03) ◽  
pp. 274-287
Author(s):  
C. GODET ◽  
T. HEITZ ◽  
J. E. BOURÉE
Keyword(s):  
Local Structure ◽  
Carbon Films ◽  
Dissociation Rate ◽  
Elastic Recoil ◽  
Electron Hole ◽  
Elastic Recoil Detection ◽  
Bonded Materials ◽  
Infrared Ellipsometry ◽  
Quantiative Analysis

In order to understand better the electronic properties of π-bonded materials, some optical and photoluminescence properties of amorphous carbon films have been investigated as a function of film density (0.9 to 1.7 g.cm-3). This study gives an overview of the radiative recombination properties in relation with local structure characterizations (in situ infrared ellipsometry and Raman spectroscopies) for a series of dual-plasma deposited polymer-like a-C:H films. Medium range topology has consequences in the hyperconjugation effects seen on infrared bands, as well as in optical and resonant Raman characteristics. Photoluminescence (PL) excitation spectroscopy reveals resonance features which are attributed to exciton-like electron-hole pairs in close Coulomb interaction. The PL efficiency shows a sharp quenching for densities above 1.3 g.cm -3 where a clear transition also occurs in the Raman "fingerprint". In addition, quantiative analysis of IR ellipsometry and Elastic Recoil Detection give evidence of a strong decrease of both the effective dynamical charge e*(C-H) and the bandwidth of sp 3 C-H vibrations; this is interpreted as being a result of the increase of local strains in the carbon skeleton, meaning that matrix distortions already appear at H content values as high as 46 H at .% due to film densification. An expected consequence is the mixing between π and σ molecular orbitals and the enhancement of the dissociation rate of confined electron-hole pairs. PL quenching would thus result form both a decrease of exciton confinement and an increase of the density of accessible nonradiative centers.

Water dissociation phenomena in a bipolar membrane

1999 ◽  
Vol 42 (6) ◽  
pp. 589-598 ◽  
Author(s):  
Tongwen Xu ◽  
Weihua Yang ◽  
Binglin He
Keyword(s):  
Water Dissociation ◽  
Bipolar Membrane

Electrochemical Performance Evaluation of Bipolar Membrane Using Poly(phenylene oxide) for Water Treatment System

2020 ◽  
Vol 20 (11) ◽  
pp. 6797-6801
Author(s):  
Tae Yang Son ◽  
Jun Seong Yun ◽  
Kihyun Kim ◽  
Sang Yong Nam
Keyword(s):  
Tensile Strength ◽  
Ion Exchange ◽  
Water Splitting ◽  
High Efficiency ◽  
Ion Exchange Membranes ◽  
Bipolar Membrane ◽  
Porous Support ◽  
Bipolar Membranes ◽  
Phenylene Oxide ◽  
Exchange Membrane

This study describes the use of poly(phenylene oxide) polymer-based ion-exchange polymers, polystyrene-based ion-exchange particles and a porous support for fabricating bipolar membranes and the results of an assessment of the applicability of these materials to water splitting. In order to achieve good mechanical as well as good ion-exchange properties, bipolar membranes were prepared by laminating poly(phenylene oxide) and polystyrene based ion-exchange membranes with a sulfonated polystyrene-block-(ethylene-ran-butylene)-block-polystyrene) (S-SEBS) modified interface. PE pore-supported ion-exchange membranes were also used as bipolar membranes. The tensile strength was 13.21 MPa for the bipolar membrane which utilized only a cation/anion-exchange membrane. When ion-exchange nanoparticles were introduced for high efficiency, a reduction in the tensile strength to 6.81 MPa was observed. At the same time, bipolar membrane in the form of a composite membrane using PE support exhibited the best tensile strength of 32.41 MPa. To confirm the water-splitting performance, an important factor for a bipolar membrane, pH changes over a period of 20 min were also studied. During water slitting using CA-P-PE-BPM, the pH at the CEM part and the AEM part changed from 5.4 to 4.18 and from 5.4 to 5.63, respectively.

Sign in / Sign up

Export Citation Format

Share Document