Determination of freezing points and amounts of impurity in hydrocarbons from freezing and melting curves

Abstract

Simple time-temperature freezing and melting curves are analyzed, and a procedure is outlined for determining from them the freezing point of a given substance and the amount of impurity in it. The procedure was applied to a number of different known solutions of hydrocarbons ranging from 0.006 to 0.115 mole fraction in concentration of solute. For the systems examined, it was found that the values for the freezing point of a given substance obtained from both freezing and melting curves were always in accord within their respective limits of uncer-tainty, and that the estimated amount of impurity was in error by not more than about 10 percent of itself, on the average.