Diaphragms modified deposited asbestos

The primary variables [87,88] in depositing a diaphragm are the asbestos type and bath composition, rate of deposition, and baking, which are elaborated below. The guidelines discussed here are applicable with all the modifiers, although the precise values of the operating variables depend on the requirements at a given site. 

Separation of the anode and cathode products in diaphragm cells is achieved by using asbestos [1332-21 -4] or polymer-modified asbestos composite, or Polyramix deposited on a foraminous cathode. In membrane cells, on the other hand, an ion-exchange membrane is used as a separator. Anolyte—catholyte separation is realized in the diaphragm and membrane cells using separators and ion-exchange membranes, respectively. The mercury cells contain no diaphragm the mercury [7439-97-6] itself acts as a separator. 

The current cell employs vertical DSA coated titanium anodes, vertical cathodes of woven wire mesh bolted to a perforated steel backplate, and a vacuum-deposited modified asbestos diaphragm. A single bipolar element may have 100 m of both anode and cathode active area. The anode of one element is connected to the cathode of the next by copper spring clips. This connection is immersed in the cell liquor during operation. Figures 33 B and 34 show these internal cell parts. 

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