Application of deep eutectic solvent as novel co-solvent for oil extraction from flaxseed using sonoenergy

The extraction of oil from flaxseeds were carried out using deep eutectic solvents (DESs) and organic solvents with ultrasound assisted extraction. Enhancement of solvent extraction was investigated by adding novel co-solvents in the form of DESs to tetrahydrofuran (THF) and n-hexane. COSMO-RS, UFF and DFT computational method was used to study the solubility of organic solvents and DESs for oil extraction from flaxseed. It was noted that the solvent share the same non-polar region on the σ-profiles with the flaxseed oil model. Different organic solvents were screened and it was found that n-hexane and THF can achieve the highest oil yield. The addition of DES to THF negatively impacted oil yield. On the other hand, the addition of DES to n-hexane can slightly improve the extraction yield and significantly reduce the extraction temperature in comparison to n-hexane alone. Application of DES as novel co-solvent with other organic solvents can be translated to economic benefits through reducing the energy consumption and operational risks associated with the use of flammable solvent such as n-hexane. • Deep eutectic solvent (DES) introduced as co-solvent for oil extraction enhancement • Oil extraction from flaxseed was carried out with ultrasound assisted extraction • DES co-solvent added to tetrahydrofuran and hexane to observe extraction efficiency • DES co-solvent yielded comparable extraction efficiency at lower temperatures • Lower extraction temperature can be related to economic benefits and process safety