Graphite Oxide Membranes

Inorganic membranes Glass hollow fiber Glass hollow fiber Graphite, oxidized Schott A Gen. Westinchouse (Union Carbide Comp.) SO 98 80 120 41 0.5 0.5 ... 

Graphite membranes are obtained by drying a graphitic oxide gel on a polished surface, reducing with hydrogen at temperatures above 500°C and graphitizing the carbon membrane formed at temperatures above 2500°C. 

See osmosis. The pressure forces the water component of the solution through the membrane, thus effectively separating the components of the solution. Membranes used are cellulose acetate or graphitic oxide. This method is planned for use in a desalination plant proposed for the brackish waters of the lower Colorado River that is said to be the world s largest. It is also used in a Potomac River installation. (4) Flash distillation appears to be the most effective method so far developed for seawater desalination, accounting for about 90% of world production capacity. 

H. P. Boehm, A. Clauss, U. Hofmann, J. Chim. Phys., 58, 141 (1961). Review on graphite oxide and membranes thereof. 

Xu C, Cao Y, Kumar R et al (2011) A polybenzi-midazole/sulfonated graphite oxide composite membrane for high temperature polymer electrolyte membrane fuel cells. J Mater Chem 21 11359-11364... 

Xue C, Zou J, Sun Z et al (2014) Graphite oxide/ functionalized graphene oxide and polybenzimidazole composite membranes for high temperature proton exchange membrane fuel cells. Int J Hydrogen Eneigy 39 7931-7939... 

State-of-the-art thin film Li" cells comprise carbon-based anodes (non-graphitic or graphite), solid polymer electrolytes (such as those formed by solvent-free membranes, for example, polyethylene oxide, PEO, and a lithium salt like LiPFe or LiCFsSOs), and metal oxide based cathodes, in particular mixed or doped oxides... 

Other applications of supported liquid membranes have been related to metal speciation. For example, recently a system for chromium speciation has been developed based on the selective extraction and enrichment of anionic Cr(VI) and cationic Cr(III) species in two SLM units connected in series. Aliquat 336 and DEHPA were used respectively as carriers for the two species and graphite furnace atomic absorption spectrometry used for final metal determination. With this process, it was possible to determine chromium in its different oxidation states [103]. 

The membrane and electrode assembly used for the detection of oxides of nitrogen is similar to that used for CO detection, except that the sensing electrode is fabricated from a graphite Teflon mix. 

Pt/XC-72R catalyst mixture that was sprayed directly onto one of the graphite separator plates that came with the high-flow rate single-cell electrolysis cell. We have found that the copper(I) oxidation reaction does not require a catalyst (see below). Thus, a catalyst-free graphite separator plate was used as the anode. Nafion membranes were used as the electrolyte for H+ conduction. 

The experimental data presented in this paper demonstrates the potential of CuCl/HCl electrolysis for nuclear hydrogen production. The CuCl/HCl electrolysis reaction requires a cation exchange membrane in order to produce hydrogen at a current density that exceeds 0.1 A-cm-2. In order to carry out the hydrogen production reaction a platinum electro-catalyst is required. The copper(I) oxidation reaction, on the other hand, does not require a Pt catalyst. This reaction proceeds quite readily on Pt-free graphite electrodes. Methods to mitigate the passage of the copper ion species across the membrane need to be developed to maintain the performance of the cell at the desired level. 

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