MINI-FLUIDIC SILVER BASED SOLVENT EXTRACTION OF EPA/DHA FROM FISH OIL

Abstract

The extraction of Omega 3 PUFA using silver ions was compared within a mini-fluidic and conventional stirred-tank reactor, with practical extraction yields of EPA –Et, DHA- Et approaching 60 to 70 Wt.%. Equilibrium was reached in less than 36 seconds in the mini-fluidic reactor at 10°C, despite stratified flow being observed rather than previously reported slug-flow profiles. The deviation in flow pattern was attributed to a measured order of magnitude reduction in the interfacial tension between fish oils and AgNO3 solution relative to idealized solvent mixtures often employed in previously reported literature on this extraction. A conceptual process design for silver based solvent extraction of Omega 3 PUFA at an industrial scale was explored, and suggests that this process can be feasible with appropriate silver recycling strategies with regeneration costs approaching $0.70 per kg of fish oil processed.