Electro sorption

Graphite finds wide range of applications in the electrodes for certain types of rechargeable batteries and supercapacitors, in electro-sorption/desorption electrodes, as anodes in a number of processes of... 

Electro sorption at electrodes and its relevance to electrocatalysis and electrodeposition of metals. 

We will come back to the lyotropic sequence in sec. 3.10g and to the electro-sorption of organic molecules on silver Iodide in sec. 3.12. 

Instance, n-alcohols do not influence o (pH) curves on alumlnall, although they do so on rutile ). Best studied is the adsorption of surfactants but, although the Influences of and pH are sometimes considered, systematic a° plus electro-sorption Investigations are virtually non-existent. 

Electro-sorption Electrochemical reduction Electrochemical oxidation... 

Main Characteristics of Kaowool 700 Grade Paper That Was Used for Preparation of Electro-Sorption Membranes... 

FIGURE 40.5 Schematic representation of the electro-sorption experiment. 

Chemical Composition of Two Model Effluent Solutions Used in Electro-Sorption Experiments... 

Chemical Composition of Ni Effluent before Electro-Sorption, after Electro-Sorption, and after Desorption Experiment (mg L )... 

Purification Degree of Mine Effluent Model Solution as a Result of Electro-Sorption Experiment... 

R. E. Lacey. Electro sorption and Desorption Process for Demineralization. Report 398. U.S. Office of Saline Water Research and Development Program, 1969. 

The same relationships also apply to the enthalpy and the entropy of electrosorption. The enthalpy of electro sorption turns out to be less (in absolute value) than the enthalpy of chemisorption of the same molecule on the same surface from the gas phase. On the other hand, the entropy of chemisorption from the gas phase is, as a rule, negative, since the molecule RH is transferred from the gas phase to the surface, losing in the process three degrees of freedom of translation. This is also true for electrosorption, but in this case n molecules of water are transferred from the surface to the solution, leading to a net increase of 3 (n— 1) degrees of freedom. As a result, the entropy of electrosorption is usually positive. Remembering the well known thermodynamic relationship... 

Thermal GLC Diffusion Condensation Sorption GSC Sorption Volatili- zation LLC Distilla- tion Extraction LSC Ppt1 n Electro-deposition Crystallization Ring Oven Subli- mation Soln. Zone Refining Sieving Magnetic Techniques... 

As the mobile phase moves through the capillary containing the sorbent under the effect of this electro-osmotic flow (EOF), sample components partition between the two phases in sorption and diffusive mechanisms characteristic of liquid chromatography. Ions in the sample move both under the influence of EOF and by their added attraction toward the oppositely charged electrode (electrophoresis). Uncharged components, on the other hand, move only under the influence of EOF. Thus, sample components, in general, separate by chromatographic and, sometimes, electrophoretic processes. 

Kreuer et al. [25] investigated the membrane properties, including water sorption, transport (proton conductivity, electro-osmotic water drag and water diffusion), microstructure and viscoelasticity of the short-side-chain (SSC) perfluorosulfonic acid ionomers (PFSA, Dow 840 and Dow 1150) with different lEC-values. The data were compared to those for Nafion 117, and the implications for using such ionomers as separator materials in direct methanol and hydrogen fuel cells discussed. Tire major advantages of PFSA membranes were seen to be (i) a high proton conductivity. 

The heavy metals are removed predominantly by the electromigration process, while the organic contaminants are removed by electroosmosis. The presence of heavy metals causes the zeta potential of the soil to be less negative and even result in a positive value, affecting the electro-osmotic flow and sorption of the contaminants. 

The transport of contaminants under an electrical field in soil is governed by several processes, including electromigration, electro-osmosis, diffusion, sorption, solubilization, and chemical and biological reactions. 

The sorption and desorption of chlorinated pesticides limits the potential success of electro-osmotic transport. The sorption of hydrophobic organic compounds (HOCs) is a partitioning type of process and can be represented by linear isotherms until aqueous phase solubility is approached (Chiou, Peters, and Freed, 1979). Karickhoff (1981) reported that the sorption isotherm was linear for HOCs up to half of the aqueous phase solubility level of the solute. Although HOCs adsorb to mineral surfaces mainly due to van der Waals forces (Schwarzenbach, Gschwend,... 

Cosolvent-enhanced electrokinetic remediation of chlorinated pesticides has yet to be explored. Few studies have shown enhancements in the transport of polycyclic aromatic hydrocarbons (PAHs) when cosolvents were used (Maturi and Reddy, 2008 Reddy and Saichek, 2003). The potential success of cosolvents depends on their ability to mobilize the HOCs and to increase the EOF. It was shown that 10% n-butylamine generated the greatest EOF, followed by 20% n-butylamine and water (Maturi and Reddy, 2008). The sorption of solvents to the soil matrix may not be as high as the surfactants, which cause a better solubilization with the same amount of electro-osmotic transport. 

A humidity-sensitive conducting polymer actuator made up of PEDOT doped with poly(4-styrenesulfonate) (PEDOT/PSS) was fabricated [47]. Water vapor sorption and electro-active actuating behavior of free-standing PEDOT/PSS films were investigated by sorption isotherm and electromechanical analyses. The non-porous PEDOT/PSS film, with a specific surface area of 0.13 m g sorbed water vapor of 1,080 cm (STP)g , corresponding to 87 wt%, at relative water... 

Okuzaki, H., and K. Funasaka. 2000. Electro-responsive polypyrrole film based on reversible sorption of water vapor. Synth Met 108 127. 

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