Competitive study on separation and characterization of microcrystalline waxes using two deoiling techniques

One stage fractional crystallization and solvent extraction techniques have been used to separate different microcrystalline waxes grades with different characteristics from Suez crude petrolatum. One stage fractional crystallization has been done using butyl acetate as solvent at ambient temperature of 20 °C, at different dilution solvent ratios (S/F by weight) ranging from 2:1 to 8:1 and constant washing ratio of 2:1. While, solvent extraction technique has been done at different extraction temperatures and different solvent feed ratios (S/F by weight). The extraction solvents used are dimethyl-sulfoxide (DMS), N, N, dimethyl-acetamide (DMA), and N-methyl-2-pyrrolidone (NMP). The wax products are evaluated according to TAPPI-ASTM equation and petroleum wax specifications. The data revealed that solvent extraction technique is more suitable for deoiling Suez crude petrolatum than one stage fractional crystallization technique. Also, the resulting data revealed that DMA and NMP are suitable extracting solvents for isolating of microcrystalline waxes from Suez crude petrolatum. But, according to petroleum wax specifications, DMS is not a suitable solvent for separation of microcrystalline wax from Suez crude petrolatum.

► Fractional crystallization &solvent extraction for deoiling petroleum waste by-product.
► Solvent extraction technique is more preferable.
► Obtained microcrystalline waxes according to TAAPI-ASTM equation and petroleum wax specifications.