SUPERCRITICAL EXTRACTION OF LINSEED OIL: ECONOMICAL VIABILITY AND MODELING EXTRACTION CURVES

Abstract

The aim of the present study was to use supercritical technology to recover linseed oil (Linum usitatissimum L.) using carbon dioxide (alone or modified with ethanol as solvent) to determine the influence of the technique on the chemical composition of the oil obtained, model the kinetic curves of extraction, and estimate the manufacturing cost of the process. The experiments were conducted at 323 K, pressure of 25 MPa, constant solvent flow of 1.7 × 10⁻⁵ kg/s, and extraction time of 5 h. The highest yield was obtained with the addition of cosolvent (28.8%). The SFE process of linseed oil manufacture proved to be economically viable, resulting in a product with a specific cost of 13.21 US$/kg_oil. As to oil composition, the main fatty acids detected were linolenic and oleic acid.

Keywords:

• Carbon dioxide
• Flaxseed
• Linum usitatissimum L.
• Linseed oil
• Manufacturing cost

Acknowledgments

The authors thank LASEFI/FEA/UNICAMP for permission to use the TECANALYSIS software and the National Council for Scientific and Technological Development (CNPq) for financial support.

Notes

^a Only CO₂ was used as extractive solvent.

^b CO₂ + ethanol at 5% (v/v).

nd = not determined.

FCI = value of fraction of investment (US$/year); CRM = raw material cost (US$/year); COL = operational labor cost (US$/year); CUT = utilities cost (US$/year); CWT = waste treatment cost (US$/year); COM = manufacturing cost (US$/year).