Comparative study on separation and characterization of high melting point macro- and micro-crystalline waxes

In order to separate and characterize the high melting point macro- and micro-crystalline waxes from two different waste crudes (El-Ameria heavy slack wax and Alexandria crude petrolatum, respectively), one stage fractional crystallization has been done to separate these waxes by using different solvents at different fractionating solvent ratios ranging from 4:1 to 10:1 by weight and at constant washing solvent ratio of 2:1. The solvents used are butyl acetate, tertiary butyl acetate and cyclohexane at ambient temperature of 20 °C. Also, the fractionating temperature was studied in the range of 20–40 °C. The resulting products were subjected to bauxite adsorption treatment technique to bleach and purify the waxes. Also, different tools of analysis such as GC, XRD, DSC & TGA, H NMR, and SEM were used to characterize and compare the produced waxes. Data revealed that, butyl acetate solvent at solvent ratios of 6:1 and 8:1 by weight at fractionating temperature of 40 °C were selected as the most suitable conditions for obtaining the highest melting point macro- and micro-crystalline waxes having different n-paraffin contents, crystallinities, thermal characteristics, and degrees of branching and owning different crystal sizes. These waxes are considered as ceresins and can be used in different industrial applications.