Crystallization of a multiparaffinic wax in normal tetradecane

The thermodynamic and structural studies of the formation of solid deposits in solutions, that consist of a commercial multiparaffinic wax in the normal tetradecane, used as solvent, are carried out by X-ray diffraction as the temperature decreases from the liquid state, chromatography analyses of (liquid and solid) phases separated at equilibrium, and simple and differential thermal analyses. The experimental results highlight that the first deposits, observed just below the liquidus point, form a single orthorhombic multi-C, solid solution that consists of all the n-alkanes of the commercial wax from C-20 to C-42; the thermodynamic behaviour of (wax + C-14) mixtures in the course of the crystallization resembles binary eutectic solidification of the C-14 solvent on the one hand, and the wax as a single pseudo-component on the other hand. (C) 2000 Elsevier Science Ltd. All rights reserved.