Selective Absorption of Gaseous Hydrocarbons

An analysis of a patent specification on this procedure affords an example of the effectiveness of the R-line approach in bringing into focus the essential pattern of 

The solubility in Sp of 13 hydrocarbons with bp 4 C were reported in the form ml gas/100 ml Sp for 26°C at presumably a total pressure of 1 atm (see Table 29). These vol./vol. values are in the mole ratio form, and since Spis common to all the systems, the vol./vol. values are approximately comparable among themselves but are not so with vol./vol. values entailing another liquid S because the density and molecular weight of S are disturbing factors. The density of Sp was not stated nor 

The pressures were recorded as psia, and these have been converted into atmospheres (1 atm = 760 mm Hg). The volumes of gas recorded appear to be those measured at 1 atm i.e., the mass of gas represented by the volume for 1 atm at 25°C is the mass of gas dissolved by Sp at the stated Pa atm. In Fig. 136,1 have plotted the Na vs Pa values for ethane and ethene. It is seen that the ethene line is just on the left of the R-line for ethene, but the line for ethane is much further to the left of the R-line for ethane. This would appear to indicate that the acid function of Sp has some effect with reference to the basic function of the double bond. However, it is desirable to compare the data with those for an alcohol such as isopropanol. 

In Fig. 137,1 have indicated how the few data for the other named hydrocarbons fit into the R-line diagram. The propene line is nearer the R-line for propene than the propane line is to its own R-line, and both lines are on the left of each R-line. The lines for the remaining hydrocarbons are decidedly on the left of each R-line. 

An estimate of the intensity of the basic function of unsaturated hydrocarbons has been given on the basis of the mp curves of binary mixtures with HCl and HBr at low temperatures. Terres and Assemi (1956) described the formation of more 

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