Graphite anode

Fig. 7-1 Material consumption from impressed current anodes. graphite anode without coke backfill, O graphite anode with coke backfill, FeSi anode without coke backfill, A FeSi anode with coke backfill.

Successful electrolysis of aluminum requires a liquid medium other than water that can conduct electricity. The key to the Hall-Heroult process is the use of molten cryolite, Na AlFg, as a solvent. Cryolite melts at an accessible temperature, it dissolves AI2 O3, and it is available in good purity. A second important feature is the choice of graphite to serve as the anode. Graphite provides an easy oxidation process, the oxidation of carbon to CO2. ... 

Fig. 357. Preparation of strontium amalgam. a electrolysis cell b mercuiy cathode c current lead (Pt wire) d porous clay cell e anode (graphite rod) f, g water-cooled coils.

Titanium covered by platinum or by dioxide of manganese, ruthenium, iridium or other substances is most commonly used as an anode. Graphite and graphite covered with lead dioxide have also been used as anodes. Under some conditions, high pH and absence of salts in the anolyte, nickel can be used as the anode. Stainless steel is commonly used as the cathode. If current reversal is employed, the same material, platinized titanium or graphite, is used for both electrodes. Electrode chambers should be flushed with a large flow of rinse solution in order to remove the electrode reaction products. 

The model geometry is described in two dimensions. In x-direction the flux of ions and electrons accounts for charge transport perpendicular to the cell layers. The influence of ohmic drops within the current collectors is assumed to be zero, thus only three domains are taken into account. These are the anode (graphite), a porous separator and the cathode (LiFeP04). The solid diffusion within the electrode s active material particles is calculated in an additional pseudo-dimension in spherical coordinates. So at every point x within an electrode domain a second dimension r is used to describe this flux directed to or away from the particle s centre. The dimensions are coupled at the particle s surface. A binary electrolyte (one salt in one solvent) is assumed, whereas only the cation flux is described, since the anions do not contribute to the electrochemical reaction of the cell. The subscript + indicates the aforementioned cationic species (LE). 

A typical resnlt is shown in Fig. 19.10. It shows the effectiveness of propane sulton (PS) as an anode additive to improve the high-temperature stability of the anode graphite. When MCMB (graphitized mesophase carbon) 6-28 is used as the... 

Y., Bi, Z., and Yang, J. (2013) Electro-Fenton degradation of p-nitrophenol using the anodized graphite felts. 

Anode Graphite or carbon composite (rarely other materials e.g. 64115012)... 

Cathode Layered Oxide Cathode + Anode Graphite or Li/Li Eiectroiyte LiPFe in Organio Carbonates... 

The CEER process has also been used for ammoniacal etchants (Fig. 9.12(b)] when a sulphuric acid anolyte is preferred together with platinized titanium anodes graphite cathodes are retained. In this case the anode reaction is oxygen evolution etchant oxidation readily takes place chemically via dissolved oxygen in the etching machine ... 

Anode-cathode distance - 40 mm Anode - graphite and prebaked Cathode - copper plate... 

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