Abstract
The authors made the determination of water-soluble sulphate sulphur, HCl-soluble sulphate sulphur, HCl-insoluble sulphide sulphur, HCl-insoluble sulphate sulphur, and HCl-soluble sulphide sulphur in iron ores such as Takai, Gumma, Kamaishi, and pyrite-and pyrrhotite-cinders, and, using the data obtained, tried to estimate the amount of the error in FeO values determined by the usual method which arises from the reduction of ferric iron by H2S evolved from soluble sulphide and the interference of soluble ferrous compounds, especially ferrous sulphide, other then FeO. According to the results,it was found that among the materials investigated the error estemated is nearly zero only in the case of Gumma ore, which does not contain any soluble sulphide in it, while in other cases it can not be ignored, especially in the extreme case of pyrite cinder where it amounts to nearly 100%.
