Solvent extraction is a method of separating oil from nuts/seeds.
Most nuts contain oil. First the nuts are crushed to reduce their size and increase the surface area.
A suitable volatile solvent is added. The mixture is filtered.
The filtrate solvent is then allowed to crystallize leaving the oil/fat. If a filter paper is rubbed/smeared with the oil/fat, it becomes translucent.
This is the test for the presence of oil/fat.Experiment:
To extract oil from Macadamia nut seedsProcedure
Crush Macadamia nut seeds form the hard outer cover .
Place the inner soft seed into a mortar.
Crush (add a little sand to assist in crushing).
Add a little propanone and continue crushing.
Continue crushing and adding a little propanone until there is more liquid mixture than the solid.
Put the filtrate into an evaporating dish.
Vapourize the solvent using solar energy /sunlight.
Smear/rub a portion of the residue left after evaporation on a clean dry filter paper.Observation /Explanation
Propanone dissolve fat/oil in the macadamia nuts.
Propanone is more volatile (lower boiling point) than oil/fat. In sunlight/solar energy, propanone evaporate/vaporize leaving oil/fat(has a higher boiling point).
Any seed like corn, wheat , rice, soya bean may be used instead of macadamia seed. When oil/fat is rubbed/ smeared on an opaque paper, it becomes translucent.