Purifying Used Cooking Oil


This investigatory project determines the possibility of purifying used cooking oil using sedimentation method. The activated carbon was also used in the experiment to absorb some dissolved substances in the oil. There were three different setups used in this study namely; Setup 1 (sedimentation was done once); Setup 2 (sedimentation was done twice); and Setup 3 (sedimentation was done thrice).

The purified oil was compared to commercial oil in terms of color, odor, and clearness using acceptability test. Viscosity test was also done in the laboratory.

The means of the samples were compared and revealed that purified oil had no significant difference to commercial cooking oil in terms of color/clearness and odor as the result of the acceptability test. Therefore, sedimentation is a possible method of purifying used cooking oil.


Oil used in cooking foods is commonly derived from vegetables. Cooking oil is commonly used for frying. Oil used for frying is usually thrown away.

This study tried to find a way to purify used oil.

Materials & Equipment

Selected References:

Johanson G., 1993. Swedish quality requirements for oil used for margarine, and some comparative analyses of edible oils, In: P.D. Turner (editor), The Quality and Marketing of oil Product. Incorporated Society of Planters, Kuala Lumpur, pp. 20-31. Wolvesperges, A., 1992. Factors affecting the quality of oil, In: P.D. Turner (editor), The Quality and Marketing of oil Product Incorporated Society of Planters, Kuala Lumpur, pp. 45-52. Cocks, L.V. and Van Rede, C., 1993. Laboratory handbook for oil and fat analysis, Academic Press, London, p. 419.

Further clarification of the procedures and results should be directed to the researchers and adviser.

Cornelio S. Santiano
Mark Anthony M. Waminal
Gian Dave C. Dimla

Mrs. Racquel C. Diaz
Talavera National High School