40S Thornton, Jr. — Separation of Titanium from Iron, etc. 



tion of sulphuric acid be too small, the aluminum is carried 

 down with the titanium in considerable measure. 



For these experiments two standard solutions of titanic 

 sulphate were employed. These were made by acting on 

 specially prepared potassium fluotitanate with concentrated 

 sulphuric acid until all the hydrofluoric acid had been displaced, 

 diluting and making up to known volume. The first solution 

 was standardized by taking two weighed portions of 25 cra3 each 

 and precipitating the titanium by hydrolysis of the acetate 

 upon boiling in the manner previously described by the author.* 

 Duplicate determinations gave the following results : 



Titanic sulphate solu. Titanic oxide 



(a) 25 cm3 =0=27-308 grm. 0-1427 grin. 0-5226$ 



(b) 25 em3 27-319 grm. 0-1428 grm. 0'5227$ 



Since these two results agreed so closely, the value obtained in 

 (b) was arbitarily taken as correct. The second solution was 

 standardized by taking weighed portions of 25 c,n3 and 24 cm3 re- 

 spectively and determining the titanium in one (a) by the ace- 

 tate method and in the other (b) by the " cupferron" method 

 of Bellucci and Grassi.f Two determinations gave the 

 following results : 



Titanic sulphate soln. Titanic oxide 



(«) 25 cm3 =C= 27-814 grm. 0-1066 grm. 0-3822$ 



(b) 24 cmS =0=26-667 grm. 0-1022 grm. 0-3822$ 



Since these two determinations agreed exactly, the value here 

 obtained was taken as correct. 



The first series of experiments were carried out with a view 

 to obtaining favorable conditions for the separation of titanium 

 from aluminum. Known quantities of aluminum were added 

 by weighing off dry ammonium aluminum sulphate, which had 

 been purified by two recrystallizations. To the solution con- 

 taining the titanium and aluminum and a weighed amount of 

 tartaric acid (except in the case of experiments (1) and (2) which 

 were made in the absence of tartaric acid) redistilled ammonium 

 hydroxide was added until the solution became neutral to 

 litmus paper. A definite volume of sulphuric acid (made by 

 diluting one volume of acid of sp. g. = 1-84 with an equal 

 volume of water) was then added and the solution made up to 

 the volume designated in the last column of Table I. Twenty 

 cubic centimeters of a 6 per cent "cupferron' 1 solution was 

 then added and the beaker set aside for the precipitate to 

 settle. The time of standing does not appear to matter a 



* Loc. cit., p. 174. f Loc. cit. 



