Section III, 1921 [69] Trans. R.S.C. 



The Oiliness or Lubricating Properties of the Various Series of 

 Hydrocarbons 



Preliminary Report by W. F. Sever 



Presented by Professor E. H. Archibald, 



(Read May Meeting, 1921) 



It has long been a matter of speculation as to which series of 

 hydrocarbons possesses the property of lubrication or oiliness to the 

 greatest degree. It has been maintained by some authorities that 

 these properties are due to unsaturation. This view is to a certain 

 extent supported by the fact that the paraffin hydrocarbon CnH^n + o 

 series do not make good lubricating oils. The chief constituents of 

 lubricating oils belong to the series CnH2n, CnH2n— 2 ^^nd C^Hon— 4- 

 It is obvious that these series may represent either the saturated 

 naphthene or oelfin hydrocarbons. The majority of lubricating oils 

 contain both series, as their iodine number indicates. It was with 

 a view to decide which of these series of hydrocarbons possesses the 

 property of oihness or lubrication to the greatest degree that the 

 following work was done. 



As a preliminary investigation it seemed well to first determine 

 the difference that existed in regard to this property between the 

 saturated and unsaturated constituents of a mineral lubricating oil. 

 For this purpose a sample of lubricating oil was obtained from the 

 B.C. Refining Co. This had been distilled from a California crude 

 asphaltic base petroleum. Approximately 400 c.c. of this oil, in a 

 sépara tory funnel, was treated repeatedly with 50 c.c. of liquid 

 sulphur dioxide. At a temperature of — 10°C two layers formed, the 

 lower one consisting of a solution of the unsaturated hydrocarbons in 

 the liquid sulphur dioxide. This treatment was continued until the 

 lower or sulphur dioxide layer had only a slight colour after shaking. 

 After the separation of the saturated and unsaturated constituents 

 in this way the sulphur dioxide was removed by blowing carbon 

 dioxide through the oil. To insure complete removal the oil fractions 

 were washed several times with an alkaline solution, then with water, 

 and finally dried. 



The coefficient of friction of the two oils was then determined 

 by means of an Olsen friction machine. The following readings taken 



