216 W. M. Thornton, Jr.- Estimation of Titanium. 



boiled filtrate from the ferrous sulphide in an actual separation. 

 Accordingly, to a 25 cma portion of the standard titanic sulphate 

 solution exactly three times the weight of the titanium dioxide 

 in tartaric acid was added, followed by ammonium hydroxide to 

 alkalinity and then 10 to l'i 01 " 3 of concentrated sulphuric acid. 

 The solution was then evaporated down to incipient charring of 

 the tartaric acid. The basin* was then covered with a watch glass 

 and the heating continued till further charring and frothing 

 had taken place as much as the capacity of the vessel would 

 permit. After cooling a little, 5 tn|3 of fuming nitric acid were 

 added through the lip opening with a pipette. After the 

 hist violence of the reaction was over cautious heating was 

 applied. A vigorous reaction took place accompanied by 

 much effervescence and copious evolution of brown fumes. 

 The organic matter gradually disappeared. The effervescence 

 hecame steady, finally ceased and the sulphuric acid began to 

 fume. A pale yellow syrupy liquid resulted. The liquid was 

 poured into 100 (m3 of cold water, and after filtration the tita- 

 nium precipitated exactly as described under standardization. 

 Table I shows the results of five experiments carried out in 

 the above manner. 



Table I. 



The Recovery of Titanium after Oxidation of Tartaric Acid 

 by Sulphuric Acid and Fuming Nitric Acid. 





Titanic sulphate = By 



Found 



Error 





No. 



standardization Ti0 2 



Ti0 2 



Alkali salt 





cm 3 . gi'm. 



grm. 



grin. 





1. 



25 



0-1012 



0-1015 



+ 0-0003 



HJSlaSO, 



2. 



25 



0-1012 



0-1013 



+ 0-0001 



HNaS0 4 



3. 



25 



0-1256 



0-1264 



+ 0-0008 



HK80 4 



4. 



25 



0-1256 



0-1256 



o-oooo 



HKS0 4 



5. 



25 



0-1256 



0-1259 



+ 0-0003 



HKSO, 



A solution of ferric sulphate was prepared by dissolving 

 ferric ammonium alum in water and adding a little sulphuric 

 acid to prevent the formation of basic salt. The solution was 

 standardized by potassium permanganate which had previously 

 been standardized against sodium oxalate. 



In the second series of experiments actual separations of 

 titanium from iron were carried out in the manner detailed in 

 the introduction. The filtrate from the ferrous sulphide was 



* A 200 cr,,:! platinum basin of the Blair type was found to be the most sat- 

 isfactory for the purpose. 



