Process chloroalkali

By the way, note that chlorine (Cl ) is a by-product of this process. Chlorine-containing compounds have caused a number of environmental problems as talked about in Chap. 16, and the chlorine source for these compounds was essentially this process, i.e., electrolysis of the brine to produce sodium hydroxide. Because of the environmental concerns, this process called chloroalkali process is now often... 

Besides the industrial production of PCNs there is also a release of PCNs to the environment via polychlorinated biphenyl (PCB) commercial products, in which PCNs are present as minor contaminants [3], PCNs are also formed in various incineration processes [4, 5] and industrial processes such as the production of magnesium [6], copper [7] and in chloroalkali production [8,9]. PCNs are currently widespread in the environment and are to be regarded as an environmental problem [4]. In general, PCNs are present in biota at ng g 1 levels (on lipid weight basis). High levels (2.4 pgg J) have been reported in e. g., whitetailed sea eagle from Poland [5]. 

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