Abstract
Hiroshi Sogo. The present writer carried out several researches on the subject from the accuracy and easiness of the practical veiw pts, and succeeded to get the reliable results to be shown in the following summary:
(1) In case of carbon and special steels, the oxidation method by nitric and hydrochloric acid is the most reliable process to get the accurate results while the evolution method is used to show very of ten too low results by the incomplete solubility.
(2) In case of pig irons, the evolution method is only useful to estimate small Part of sulphur in it and most part of sulphur is remained in the evolution flask. The application of the oxidation method by nitric and hydrochloric acid nearly always gives low results, and in such a case conaiderable amount of sulphur is found unestimated in the remaining residue with silica and graphite.
Then in this method the residue must be re-examined for sulphur, although the treatment is very tedious and liable to do failure.
Therefore in this work, the present writer tried and succeded to determine the total sulphur in pig iron by fusion method with the mixture of sodium peroxide and sodium carbonate (1:1).
And he has found this method is the most reliable and universally applicable one for determination of sulphur in pig iron
Now then the writer is wanted to add the experimental results with three different methods to emphasize his researches which were applied to the Swedish pig irons.
