Halic acids, HOXO2, and halates

Disproportionation of X2 in hot alkaline solution has long been used to synthesize chlorates and bromates (see oxidation state diagrams, p. 855)  

For example, J. von Liebig developed the technical preparation of KCIO3 by passing CI2 into a warm suspension of Ca(OH)2 and then adding KCl to enable the less-soluble chlorate to crystallize on cooling  

However, only one-sixth of the halogen present is oxidized and alternative routes are more generally preferred for large-scale manufacture. Thus, the most important halate, NaC103, is manufactured 

Modem cells employ arrays of anodes (Ti02 coated with a noble metal) and cathodes (mild steel) spaced 3 mm apart and carrying current at 2700Am into brine (80-100gl ) at 60-80°C. Under these conditions current efficiency can reach 93% and 1 tonne of NaC103 can be obtained from 565 kg NaCl and 4535 kWh of electricity. The off-gas H2 is also collected. 

Bromates and iodates are prepared on a much smaller scale, usually by chemical oxidation. For example, Br is oxidized to Br03 by aqueous hypochlorite (conveniently effected by passing 

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