Manchester Memoirs, Vol. xlvi. ('1902), No. 11. 



XI. On a Modification of Rose's Method of Separating 

 Cobalt and Nickel. 



By R. L. Taylor, F.C.S. 



Read February i8th. Received March 4th, igo2. 



Numerous methods have been proposed for the pur- 

 pose of separating cobalt and nickel when in solution 

 together. The two metals, however, are so much alike 

 in their general properties, that very few methods appear 

 to give satisfactory results, and those few are as a rule 

 troublesome and tedious. 



The method which I have described as " Rose's 

 method " was proposed by him over 50 years ago {Pogg. 

 Annal., Bd. 71, p. 545), and a translation of Rose's paper, 

 by T. H. Henry, appeared in the Chemical Gazette for 

 1847, page 362, accompanied by some remarks on the 

 method by the translator. The process, while fairly 

 satisfactory, was very tedious and troublesome, and, 

 probably for that reason, it appears to have gone out 

 of use. It is described in Gmelin's Handbook and in 

 various editions of Fresenius' Quantitative Analysis, but 

 very few modern text-books even mention the reaction 

 (which is interesting and important) upon which the 

 method depends. For example, it is not referred to in 

 Roscoe and Schorlemmer's Treatise on Chemistry, and 

 there is no mention of it in the newer Watts' Dictionary 

 of Chemistry. 



Rose's method depends upon the fact that cobalt is 

 precipitated as the black sesquioxide by various insoluble 

 carbonates (such as those of barium, strontium and 



Aday loth, igo2. 



