SECTION III., 1902 [ 47 ] TRANS RH 167207: 
IV.-—An Experimental Investigation of the Conditions Determining 
the Oxidation of Ferrous Chloride. 
By A. McGitt, B.A., B.Sc. 
(Read May 27, 1902.) 
The following sequence of reactions, having in view the production 
of free chlorine and carbonate of soda from common salt, by the 
agency of carbon and oxygen, is satisfactory so far as theory is con- 
cerned. 
First Stage-—The decomposition of chloride of sodium by sul- 
phurie acid, with production of sulphate of soda and hydrochloric 
acid. 
Second Stage.—Treatment of the sulphate of soda with peroxide 
of iron and carbon, to produce carbonate of soda and sulphide of iron. 
Third Stage—Decomposition of the sulphide of iron by hydro- 
chloric acid, with production of ferrous chloride and sulphuretted 
hydrogen. 
Fourth Stage-—Oxidation of ferrous chloride, (by air or oxygen) 
to ferric oxide and free chlorine. 
Fifth Stage—Oxidation of sulphuretted hydrogen to sulphuric 
acid. | 
It will be seen that the complete process involves a continuous 
supply of common salt, carbon and oxygen, and furnishes a continuous 
output of carbon monoxide, carbonate of soda and free chlorine. 
The sulphuric acid and ferric oxide introduced at the first and 
second stages, are reproduced in the fifth and fourth stages respec- 
tively; while the hydrochloric acid, sulphate of soda, sulphide of iron, 
chloride of iron and sulphuretted hydrogen only exist as phases within 
the cycle. 
The following diagrammatic presentation of the cycle will make 
this more evident. In the diagram the materials used are heavily 
underlined; the substances removed from the cycle are enclosed in 
brackets; while the arrows connect the names of such substances as 
are present at different phases of the process, and undergo reciprocal 
change within it. Of these, sulphuric acid and ferric oxide, which 
are introduced at the beginning of the process, and reproduced at the 
end of it, are indicated by broken lines. 
The reaction occurring in the first stage is successfully carried 
out in the ordinary manufacture of salt cake. 
