The determination of ziroconium (and hafnium) in niobium and other metals with catechol violet

Abstract

A procedure, based on the extraction of zirconium ions with a solution of tri-n-octylphosphine oxide in cyclohexane, and the formation of a zirconiumcatechol violet complex in the organic extract, has been successfully applied to the determination of zirconium, over the range 20 to about 1000 p.p.m., in niobium. Alloying amounts of chromium, cobalt, molybdenum and tungsten do not interere.The procedure has also been satisfactorily applied to the determination of zirconium in complex nickel-base alloys, and tests have shown that the method should be equally applicable to the determination of zirconium in aluminium, copper, iron, stainless steels, magnesium, titanium, tantalum, tungsten and vanadium. In the analysis of tantalum-or tungsten-base materials, a preliminary separation of zirconium from the parent metal is necessary.Hafnium ions are also extracted into a solution of tri-n-octylphosphine oxide in cyclohexane, and produce a coloured complex with catechol violet in the organic extract; the procedure is, therefore, equally applicable to the determination of hafnium provided that zirconium is absent.

Instrumental multielement proton activation analysis of high-purity niobium using both .gamma.-ray and x-ray spectrometry

“…detector, the concentration of Ta and Na was 50 ppm and 10 ppm, respectively. c Based on different separation and determination procedures, using various definitions of detection limit: Ti (9), Fe (35), Zr (36), Mo (7, 37), Sb (10), Hf (36), Ta (38), W (7, 37). d Limits of detection calculated by using the "working" expressions proposed by Currie (39); they represent rounded limits of detection for Nb-WCT obtained under optimum conditions with regard to nuclide and line measured, cooling and counting time (see Table VII).…”

Analytical coordination chemistry :

“…The basic method as developed by Young and White [48] and more recently modified by Wood and Jones [49] has been applied with good success to the determination of zirconium in NBS-11565 a maraging steel. Briefly, the procedure involves the extraction of Zr + ^from a 7 M nitric acid medium with a 0.1 M solution of trioxtylphosphine oxide (T0P0) dissolved in cyclohexane.…”

Nonferrous metallurgy. II. Zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, and tungsten

“…Khcpkar and Dhara (247) extracted zirconium into mesityl oxide, back-extracted it into water, and determined it with alizarin. Wood and Jones (586,587) used pyrocatechol violet following a TOPO extraction and Hibbits, Rosenberg, and Williams (198) used a cupferron precipitation, then a TOPO extraction followed by a pyrocatechol violet determination. Leeb and Hecht (291) used pyrocatechol violet for zirconium in steel and Uzumasa, Hayashi, and I to (562) used it following a TTA extraction.…”

“…Concentration by extraction of their 8quinolinolates into chloroform or by anion exchange prior to spectrographic determination was proposed by Moro- I. Spectrophotometric Methods Reagent: Material (References) Xylenol orange: Ti, Nb, Ta, Mo, W (117)) Nb (132,207)) following extraction (359) Arsenazo III: Study of complexes (70); following TTA extraction (379); Hf (330); bronzes and Cu alloys ( 405)) steel and cast iron (468) Arsenazo: Study of complexes (378) Quinalizarinsulfonic acid: Silicate rocks (101) Alizarin red S: Granite (475)) Cu (518) Alizarin: Following extraction (247) Pyrocatechol violet: Following TOPO extraction (198,586,587)) following TTA extraction (562)) steel ( 291) Quercetin: Study of conditions ( 568)) Mg or Al (413) 8-Quinolinol: Mo ( 480)) Study of conditions and interferences (564) Thorin: W (527) 3" -sulfo -2",6" -dichloro -3,3' -dimethyl -4 -hydroxyfuchon -5,5'dicarboxylic acid: Study of conditions and interferences (44) Picramine R and Nitrosulfophenol S: Study of conditions (467) Naphthazarin and /3-hydronaphthazarin: Study of complexes (53) Chlorosulfophenol S: Fe(112) Fluotitanic acid-hydrogen peroxide: Study of conditions (149) 2,5-Dibromo-3,6-dihydroxyquinone: Study of complex (184) 2,6,7-Trihydroxy-9-methyl fluorone: Study of conditions (419) Nuclear fast red: Study of conditions (417) Pyrogallolsulf onephthalein: Study of complex (385) Gallein: Study of conditions and interferences (244) Review including reagents suitable for spectrophotometric determination (82) Arsenazo III: Iron and steel (232) Alizarin red S: Study of complex and interferences (459) 5-Dimethylamino-2-(2-thiazolylazo)phenol: Study of complex (334) 8-Quinolinol: Cr, Mo (271)) W ( 519)) water (346) 7-1 odo-8-quinolinol: Study of conditions and interferences (279) Xylenol orange: Study of conditions and interferences (72,…”