1984 Volume 70 Issue 10 Pages 1377-1384
A new spectrophotometric method for determination of elemental sulfur in blast furnace slag has been developed. The outline of the procedure is as follows. A slag sample is powdered with n-hexane using a disk mill and elemental sulfur in the sample is extracted into n-hexane at the same time. The ultraviolet absorption of the n-hexane layer is measured at 275 nm to determine the quantity of elemental sulfur.
By using this method elemental sulfur can be determined with high accuracy, provided the amount is higher than 0.002%. The coefficient of variations at the 0.05 and 0.2% levels of elemental sulfur are 2.3 and 1.4%, respectively. The time required for analysis of one sample is less than 10 min. There is no interference effect for sulfur compounds in the slag sample such as sulfate, thiosulfate, sulfite, sulfide and poly-sulfides.
When a slag sample is powdered under the dry condition before the n-hexane extraction, lower analytical values are obtained, because elemental sulfur changes into poly-sulfides by the reaction with Ca components of the slag sample. This chemical change is found to be suppressed by simultaneous performance of powdering and extraction. Based on this technique, an analytical method is proposed and successfully applied to determine elemental sulfur in a slag sample.