606 REPOET — 1891. 



allow, that it contained iron and carbonic oxide in the proportion of 1 equivalent 

 of iron to 4'126 of carbonic oxide, or very nearly 1 to 4. 



Since these results were communicated to the Chemical Society (J une 18, 

 1891) the author has continued the study of this bod}', in collaboratioii with 

 Dr. Carl Langer, and has obtained it as an amber-coloured liquid, which, on 

 standing, deposits tabular crystals of a darker colour, and solidifies entirely below 

 — 21° C. to a mass of needle-shaped crystals. It boils at 102° C, but leaves a 

 small quantity of green-coloured oil behind. 



Several analyses and vapour density determinations have been made, but it is 

 not yet certain whether a pure substance is in hand or a mixture of several iron 

 carbonyls. The author hopes to be able very shortly to publish a full account 

 of this interesting substance, which differs considerably in its chemical behaviour 

 from nickel carbon oxide. 



The fact that under ordinary circumstances nickel alone is acted ou when 

 a mixture of this metal with any other metallic or mineral substances is treated 

 by carbonic oxide gas led the author to institute experiments to ascertain whether 

 it would not be possible by means of carbonic oxide to extract nickel direct from 

 its ores, and such metallurgical products as nickel speiss and nickel matte. As the 

 nickel is volatilised at the ordinarj' temperature in the form of a vapour dissemi- 

 nated through other gases from which it can be deposited without first condensing 

 the nickel compound by simply heating these gases to the moderate temperature of 

 200° C, as it is thus obtained in the form of bright coherent masses of great 

 purity, as the carbonic oxide used is completely liberated and can be employed 

 over and over again, and as small quantities of the poisonous nickel compound 

 which may escape decomposition would thus never leave the closed apparatus 

 in which the process would be carried out, it seemed probable that such a process 

 might be capable of industrial application, and might prove more economical than 

 the very complicated operations metallurgists have now to resort to to produce 

 tolerably pure nickel. 



Experiments carried out under the author's instructions by Dr. Langer with a 

 great variety of nickel ores from all parts of the world, containing from 4 to 40 

 per cent, of nickel, as well as a number of samples of nickel speiss and nickel 

 matte, have proved that as long as the nickel is combined with arsenic or sulphur 

 the process is entirely successful on a laboratory scale. In the majority of cases 

 the nickel has been extracted almost completely in three to four days. 



Such ores or matte or speiss have in, the first instance to be calcined, so as to 

 convert the nickel completely into oxide. The mass is then reduced in a current 

 of hydrogenous gases, in practice water-gas, at a temperature of 450° C. It is 

 cooled down to ordinary temperature and treated with carbonic oxide in a suitable 

 apparatus. For this purpose any good apparatus for treating solids by gases, of 

 which a great number are in common use, will answer. Methodical apparatus 

 moving the reduced ore in a direction opposite to the current of carbonic oxide, at 

 the same time exposing fresh surfaces, facilitates the operation. After a certain 

 time the action of the carbonic oxide upon the nickel becomes sluggish. The mass 

 is then heated to about 350° C. in a current of carbonic oxide, which regenerates 

 the activity of the nickel. This may be done in the same apparatus, but it is 

 preferable to use a separate apparatus connected with the first, and from which it 

 is returned to the first by mechanical means, so that each apparatus can be kept at 

 the same temperature. The carbonic oxide gas can be employed dilute, as it 

 is obtained from gas-producers ; but since it is contiuuousl}' recovered, a purer gas 

 such as can be cheaply prepared by passing carbonic acid through incandescent 

 coke is more advantageous, as it extracts the nickel more quickly and requires 

 smaller apparatus. The gas charged with the nickel compound leaving the 

 apparatus is passed through tubes or chambers heated to about 200° C, in which 

 the nickel is deposited. The gas leaving these tubes is returned to the first 

 apparatus and circulates continuously. From time to time the nickel is removed 

 from the tubes in which it has been deposited. To facilitate this operation thin 

 nickel sheets bent to fit the tubes are inserted, on which the nickel deposits, and 

 which are easily taken out. The metal so obtained is almost chemically pure; 



