(262ac) Solubility of Squalene and Squalene + Palmitic Acid in Supercritical Carbon Dioxide

Amaranth (Amaranthus hypochondriacus) is an ancient crop harvested in Mexico. It is highly appreciated for its nutrimental content as protein and carbohydrates source. Amaranth is widely cultivated because its easiness of growing and consumption. Recently Amaranth oil has industrial interest due its squalene content. Amaranth seeds contain 7-8% oil, an important content of palmitic acid represents fatty acids, and squalene as non-saponifiable substance.

Last century, the greatest squalene source was shark liver oil, nowadays there is an arising concern on sea animal protection, new sources of squalene are being searched. Amaranth seed oil may be a profitable alternative.

Supercritical fluid extraction with CO₂ is environmentally benign technology over organic solvents, solubility data are important to develop extraction techniques. Semi-empirical models based on density are common approaches used to correlate experimental solubility in supercritical fluids.

Experiments based on the static-analytical method. Solubility apparatus is able to reach 450 K and 40 MPa. Binary systems; squalene + CO₂ and palmitic acid + CO_2; and ternary system; squalene + palmitic acid + CO₂; were measured at high pressure (up to 30 MPa) and temperature (313 to 333 K).

The self-consistency of the data was tested according to the density-based models proposed by Mendez-Santiago and Teja, and Chrastil, the calculated values agree with an average absolute deviation 14% for first model and lower than 0.4% for Chrastil model.