Microwave Extraction of Eugenol from Cloves: A Greener Undergraduate Experiment for the Organic Chemistry Lab

Abstract

The extraction of eugenol from cloves is a frequent experiment in organic chemistry labs at the sophomore level. In this paper, the commonly used steam distillation procedure has been modified to use microwave extraction. This change resulted in a simplified procedure, a reduction in the amount of sample required, and an increase in the efficiency of the extraction of eugenol from dried cloves. These modifications led to reduction of waste and energy use. Variations of the solvent composition, solvent volume, and amount of cloves were tested. It was found that a 50/50 v/v mixture of ethanol and water with whole cloves produced satisfactory results at the undergraduate laboratory level for the selective extraction of eugenol with 1g of whole cloves in less time than steam distillation.