Analytical method for the determination of less than five ppm of sulfur in nickel

An analytical technique for the separation and determination of less than 5 ppm of S has been developed. Ten grams of Ni are dissolved at room temperature in a solution of 0.9M in both cupric potassium chloride and hydrochloric acid. The resulting residue contains all of the S. The residue is separated on a S-free filter, washed, dried and burned in a stream of 0 to convert all of the S to sulfur dioxide. The resulting sulfur dioxide is titrated with a standard solution of potassium iodate. The proposed analytical technique gives accurate results for the determination of S in the range from 0.2-20 ppm. The precision is +0.7 ppm for the 2 ppm level. The method is also applicable to Al, Fe, Co and Cu, as well as their alloys. 13 ref.--AA.