Membranes electrosynthesis

There are various ways in which CMEs can benefit analytical applications. These include acceleration of electron-transfer reactions, preferential accumulation, or selective membrane permeation. Such steps can impart higher selectivity, sensitivity, or stability to electrochemical devices. These analytical applications and improvements have been extensively reviewed (35-37). Many other important applications, including electrochromic display devices, controlled release of drugs, electrosynthesis, and corrosion protection, should also benefit from the rational design of electrode surfaces. 

Bubble electrodes — Figure 2. Bubble electrode for electrosynthesis 1 - bubble electrode, 2 - ion exchange membrane, 3 - Pb02 anode. Arrangement A is for single-phase operation, and arrangement B and C are for two-phase electrolysis (electrolysis of emulsion) (reproduced from [v])... 

The three kinds of reactors already described in this section are all traditional cross-flow reactors with permeable plates or membranes. The electrochemical filter-press cell reactors used, e.g., for electrosynthesis, are equipped with cation-selective membranes to prevent mixing of the anolyte and the catholyte. These cell reactors are therefore good examples of the extended type of cross-flow reactors according to the definition transferred from the filtration field. The application of the electrochemical filter-press cell reactor technique... 

Sigmatropic rearrangement 677, 697 Sihca gel membranes 1082 Silphinene, electrosynthesis of 1183, 1187 Silver compounds, as oxidants 1307-1311 Silybin, synthesis of 1308, 1310 Silydianin 1180 Silylation, of phenols 934, 935 Silylcyanation, asymmetric 694, 695, 702 Simmons-Smith cyclopropanation, asymmetric 694... 

Electrosynthesis with Perfluorinated Ionomer Membranes in Chlor-Alkali Cells... 

The field of electrochemical science has been quietly revolutionized during this past decade by development and application of a new family of perfluorinated ionomer ion-exchange membrane separators in concert with new cell designs and stable electrode systems for electrosynthesis (1) (2). 

These new membranes are much more than structural supports. The perfluorocarbon structures impart oxidative and hydrolytic resistance to the membrane materials while their cationic strength rejects anions. This combination of unusual ionic character and exceptional chemical resistance makes these materials prime candidates for use as electrolytic separators for electrosynthesis (3). 

Processes that depend critically on these phenomena include energy storage and conversion, corrosion and corrosion control, membrane separations, deposition and etching by electrolytic and plasma processes, electrosynthesis of organic and inorganic chemicals, production and refining of metals, pollution detoxification and recovery, desalination, and many others. 

Liao, H., Zhang, Z., Nie, L., and Yao, S. (2004). Electrosynthesis of imprinted polyacrylamide membranes forthe stereospecific L-histidine sensor and its characterization by AC impedance spectroscopy and piezoelectric quartz crystal technique, 1. Biochem. Biophvs. Methods. 59, 75-87. 

Burton LL (1996) Electrochemistry with DuPonfs Nafion membranes, Tenth Int l Symp on Electrosynthesis in the Chem Industry. 

As compared to mesoporous oxide nanofibers, much lesser attention has been paid to their mesoporous amorphous carbon analogues. However, mesoporous carbon exhibits superior resistance to acids and bases, excellent heat resistance, as well as high intrinsic electric conductivity. Potential applications for hybrid membranes consisting of mesoporous carbon within hard templates include size-selective electrosorption, electrosynthesis of nanostructures, catalysis, separation and storage. The first reported procedure for the synthesis of mesoporous carbon nanofibers involved the preparation of... 

R.L. Dotson and K.E. Woodard, Electrosynthesis with Perfluorinated lonomer Membranes in Chlor-Alkali Cells. In A. Eisenberg and H.L. Yeager (eds), Perfluorinated lonomer Membranes, ACS Symposium Series, 180, American Chemical Society, Washington, D.C (1982), p. 311. 

Very many types of organic synthesis can now be carried out electrochemically, often more advantageously than by other means. Organic electrosynthesis, always multi-disciplinary, now includes photoelectrochemistry, electro-catalysis, bioelectrochemistry and others. Some of the scientific and technological developments which led to the present status of the field will be cited the use of potential control, the invention of the potentiostat, the combination of electrochemistry with spectroscopy, the use of ion-selective membranes the large-scale production of sorbitol, adiponitrile, and dimethyl sebacate. 

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