1989 Volume 38 Issue 12 Pages T191-T195
Vanadium content in zirconium-nickel-vanadium alloys was determined by hydrogen peroxide spectrophotometry following dissolution in nitric-hydrofluoric acids and fluoride ion masking with boric acid. Interference from coexisting elements was corrected for. Procedure: a sample (<about 1 g) containing vanadium less than 140 mg was digested with 10 ml of nitric acid (1+1) and 2 ml of hydrofluoric acid in a platinum dish and 40 ml of saturated boric acid solution were added. The solution was diluted to 100 ml with water. A 10 ml aliquot of this solution was mixed with 10 ml of sulfuric acid (1+1) and 10 ml of water, and was cooled in running water. One ml excess potassium permanganate solution (0.3 w/v%) was added. After standing for 5 min, 0.7 ml of a sodium nitrite solution (3 w/v%) was added with vigorously stirring in the presence of 4 ml of urea solution (50 w/v%). Absorbance was immediately measured at 450 nm after adding 3 ml of hydrogen peroxide (3%) and diluting to 50 ml with water.
