SPECTROPHOTOMETRIC DETERMINATION OF SMALL AMOUNTS OF TITANIUM IN ZIRCONIUM, ZIRCONIUM ALLOYS, HAFNIUM, NIOBIUM AND OTHER METALS, WITH DIANTIPYRINYLMETHANE

The reaction between titanium and diantipyrinylmethane to form a yellowcoloured complex in mineral acid solution, has been successfully applied to the direct spectrophotometric determination of titanium over the range 20-250 p.p.m., in zirconium, zirconium alloys and hafnium. Absorbance of the complex is measured at 390 nm. The proposed method is more sensitive than the peroxide method usually used for determining titanium in these materials. It is also less subject to interference from other metal ions, and can be applied to ZR30 alloy without preliminary separation of molybdenum. Simple modifications have enabled the procedure to be extended to the determination of titanium in niobium, tantalum, tungsten and molybdenum. In the analysis of materials containing appreciable amounts of niobium or molybdenum, absorbances are measured at 430 nm. © 1969.