30 8. F. Peckham — Petroleum in tts 



Since 1870 Le Bel and Mnntz,* (1872) have treated Syrian 

 asphalt and several other forms of bitumen to the solvent 

 action of ethyl ic-ether. Ethylic-alcohol was then added to the 

 solution and the bitumen precipitated. The solution and pre- 

 cipitation were repeated until the precipitated bitumen was 

 quite pure. It appears as a brown powder. From solution in 

 carbon disulphide it appears in brilliant black scales, which are 

 insoluble in light petroleum naphtha (paraffines) but dissolve 

 in the heavy distillates, which fact readily accounts for the 

 difference in color between the light and heavy natural oils. 

 These authors remark that, " Its (asphaltene) presence in nat- 

 ural bitumens proves that they have not been submitted to 

 distillation, nor even the action of a high temperature, which 

 corroborates the most generally received opinion respecting 

 their origin, that they have been directly derived from coal or 

 lignite." 



Subsequent research by Le Bel showed that a resinous sub- 

 stance remained dissolved in the ether that was readily acted 

 on by sulphuric acid. Distillation converted it into a residue 

 of carbon, light oils and gas. These light oils when treated 

 with iodohydric acid yielded compounds of the olefine series. 



Later, Cabotf discovered that paraffines subjected to the 

 action of sulphur at temperatures above their boiling points 

 were converted into hydrogen sulphide and carbon. At about 

 the same time Jenney,;j; aspirated air continuously for forty or 

 more hours, through refined illuminating and lubricating oils, 

 in presence of litharge and at a temperature of 100° C.-110° C. 

 By this means he converted a portion of the oil into a solid 

 oxidized residue, a portion distilled into the receiver, and a 

 portion remained in the retort. These residues were either 

 brilliant black solids or brownish flocculent precipitates, which 

 were all soluble in carbon disulphide. 



Lastly, I have lately found that a heavy fraction of a distil- 

 late, that was a transparent mobile fluid, obtained by distilling 

 California petroleum at nearly a red heat, when left to stand 

 in an open Becker glass for from 12-14: months, had become 

 so charged with asphaltene, that the addition of petroleum 

 naphtha or any of the liquids in which asphaltene is insoluble, 

 at once produced a brown flocculent precipitate. This obser- 

 vation completely contradicts the conclusion reached by Le 

 Bel and Muntz, and stated above, that natural oils containing 

 asphaltene could not have been distilled or subjected to high 

 temperatures. 



* Bulletin de la Societe Chemique de Paris, xvii, 156. 



f American Chemist, vii, 20; Chemical News, xxxvi, 114; Wagner's Berichte, 

 1876, p. 1110. 

 % American Chemist, v, 309; Wagner's Berichte, 1875, p. 1060. 



