Some Physical Properties of the Ternary System: Ethylene Glycol: Diethylene Glycol: Water

Abstract

aqueous solution of mixed glycols in place of solutions of single glycols. It is known that the freezing points of the binary system, ethylene glycolwater, is not a linear function of the composition (2); the freezing point of the solution is lower than that of either of the components. It might be assumed that, in a ternary system, each of the three components present tend to produce a greater lowering of the freezing point of the entire system than would be found for a binary system of two of the same components. It also may be expected that to reach the freezing point lowering produced by a definite composition of ethylene glycol-water, a smaller composition of ethylene glycol-diethylene glycol mixture might produce the same depression. Since there is no method reported for calculating exact freezing point lowering in ternary systems of volatile components, it was necessary to determine experimentally the freezing point depression in the ternary system, ethylene glycol-diethylene glycol-water in order to test the validity of the assumptions made. Also since the value of an antifreeze depends on the freezing and boiling points of its solutions, and upon the ease of identification of composition, values of freezing and boiling temperatures were found, and index of refraction and relative density were chosen as identification constants.