In Castner's process (as employed at Oldbury and Niagara Falls and in Germany) fused caustic soda is electrolysed.
Soc., 1856, p. 30) electrolysed an equimolecular mixture of potassium and calcium chlorides (which melts at a lower temperature than potassium chloride) also between carbon electrodes; whilst Castner's process, in which caustic potash is electrolysed, is employed commercially.
Castner's sodium patents appeared, and The Aluminium Co.
Of Oldbury was promoted to combine the advantages of Webster's alumina and Castner's sodium.
Per lb, the greater part of the expense being due to the constant failure of the retorts; in 1887 Castner's sodium cost less than is.