Thornton and Hay den — Separation of Zirconium.. 137 



Art. IX. — The Separation of Zirconium from Iron and 

 Aluminum with the Aid of the Ammonium Salt of Nitro- 

 sophenylhydroxylamine (" Cupferron " 'J ; by William M. 

 Thornton, Jr., and E. M. Hayden, Jr. 



[Contributions from the Kent Chemical Laboratory of Yale Univ.— cclx.] 



In connection with a study of potassium ferrocyanide, 

 Schroder* has stated that both titanium and zirconium could 

 be quantitatively precipitated by the il cupferron" reagent 

 from their acidified solutions and that experiments were in 

 progress for estimating these two elements. Schroder gave no 

 experimental data and, as far as the authors of this paper can 

 ascertain, has not published further upon the subject. Bel- 

 lucci and Grassif have shown the " cupferron " reagent to be a 

 quantitative precipitant for titanium and that a clean separa- 

 tion of titanium from aluminum could be brought about in 

 solutions notably acid with either sulphuric or hydrochloric 

 acid. Following the work of Bellucci and Grassi, one of usj 

 has pointed out that, after throwing down the iron as ferrous 

 sulphide from a solution containing sufficient ammonium tar- 

 trate to hold up titanium, and after acidifying the iron free 

 filtrate, the titanium can be quantitatively precipitated by the 

 " cupferron " reagent notwithstanding the presence of tartaric 

 acid ; and, further, that, if the above-mentioned filtrate be 

 strongly acidified with sulphuric acid and contain also a suffi- 

 cient quantity of tartaric acid, titanium can be quantitatively 

 separated from both aluminum and phosphoric acid in one 

 operation. § On account of the great similarity in chemical 

 nature between titanium and zirconium it appeared probable 

 that in a similar way zirconium conld be parted from the three 

 substances mentioned above. Experiments with a view to 

 accomplishing these separations were very successful as far as 

 iron and aluminum were concerned. In the case of phosphoric 

 acid, however, it was found that the zirconium derivative of 

 nitrosophenylhydroxylamine,f even when the former was 



assuming a formula analogous to the one 

 lucci and Grassi for the 

 '4 titanic derivative. 



tnC 6 H 5 — N = N — — ""I assuming a formula analogous to the 



|| Zr, proposed by Bellucci and. Grassi for 



*- O — '4 titanic derivative. 



present with the zirconium in relatively small quantities, 



carried down very appreciable masses of phosphoric acid ; 



although the test solution contained 40 cm3 of sulphuric acid 



(1 : 1) and 5 grm. of tartaric acid in a total volume of 400 cm3 . 



* Zeitschr. anorg. Cheni., lxxii, 89, 1911. 

 f Gazzetta Chimica Italiana, Anno xliii, Parte I, 570, 1913. 

 X This Journal, xxxvii, 173, 1914. 

 Ibid., xxxvii 407, 1914. 



