Isolation of Eugenol from Cloves

The experiment conducted, isolation of eugenol from cloves, is the extraction of the essential oil. To perform this experiment cloves and water were mixed together and heated by a heating mantle in a round-bottom flask. A direct stem distillation took place, and the oil product was out aside for a week. After one week, the isolation of the eugenol actually takes place. Next the thin-layer chromatographic analysis takes place, but the experiment did not proceed to that step due to the incorrect amount of NaOH.

Introduction

The isolation of eugenol from cloves is isolated from ground cloves using the technique of steam distillation, which is often used to isolate liquid natural products from plants. Essential oils are also used to produce flavoring, fragrance, and cleaning products. The compounds found in the essential oil of cloves are eugenol, eugenol acetate, and B-caryophyllene. Smaller amounts of compounds found in the essential oil of cloves are hydrocarbons, alcohol, phenol, ether, aldehyde, ketone, acid, and ester. Essential oils are volatile and have an odor. Essential oils are often flammable, soluble in alcohol and ether but partially soluble in water. The technique used was steam distillation. The steam distillation technique was used because it lowers the pressure in the flask so that it does not have to be heated at such a high temperature. High temperatures could possibly decompose organic compounds.

Experiment

The first procedure used in the experiment was 25.3g of whole cloves into a 500ml round flask. Then add 150ml of water into the 500ml round flask. Connect the apparatus, funnel with water, distillation head, condenser, and receiver using grease and clips to hold the equipment together. Connect the equipment to a stand by the separatory funnel so it can stand alone. Place the 500 round flask into the heating mantle. Place two pipes in the two openings of the equipment. The opening closest to the 500ml round ball flask, the water will be exiting into the drain. The opening closest to the 250ml round ball flask, the water will be entering. A pipe was placed in the water outlet and turned on The water began to boil the cloves. Distilling continued until 75ml of the liquid was collected. When the water boiled to high the heat was decreased to prevent bumping. When the water level got low water was released in the 500ml round ball flask from the separatory funnel. The liquid collected was sealed with a stopper and set aside until the next lab.

The next lab, 6g of NaCl was assed to 100ml distillacte. The solution was poured into the separatory funnel. In the separatory funnel 25ml of CH2Cl2 was added, and the two solutions separated. The dichloromethane was higher density liquid and the aqueous solution was the lower density liquid. Pressure was released from the separatory funnel and tipped over 3 times. The dichloromethane which was the bottom layer was drained and collected into Erlenmeyer flask. After repeating this step 3 times, the aqueous solution was discarded which appeared white and cloudy.

Next CaCl2 was added to the flask containing CH2Cl2 extract into a graduated cylinder which was 58ml. From the total amount of the 58ml CaCl2 and CH2Cl2, one-fifth of the solution which was 11.6ml was added into an erlenmeyer flask and boiled. While boiling the CH2Cl2 evaporated. Before the solution was transferred into the vial, the vial was pre-weighed. After the solution was added the vial a hairdryer was used. The vial weighted 2.17g.

Four-fifth of the CH2Cl2 extract was transferred in the separatory funnel. 25 percent of the 50 percent NaOH was added to the separatory funnel, and collected the aqueous layers. The process was repeated 3 times. The CH2Cl2 solution was kept as well. The separatory funnel was washed with 25ml of CH2Cl2. The CH2Cl2 was then discarded and the aqueous solution was capped and left for next lab. Before CaCl2 was added to CH2Cl2 extract an Erlenmeyer was pre-weighed at 117.26g. The solvent then evaporated and weighed in at 142.45. The solvent was stored to the next lab. The next week the experiment did not go to completion.

Results

The amount of the essential oil was the little vial times 5 which was 10.85g. The amount used to isolate the essential oil was the little vial times 4 which was 8.68g. From the amount CaCl2 and CH2Cl2 solvent was 25.19g. The other results were not completed due to an error in the experiment.

Discussion

The experiment did not go to completion, because 50 percent of NaOH was used instead of 5 percent of NaOH. The pH was 15 percent. The complete process of the experiment is steam distillation of the eugenol in cloves. After the eugenol is in the distillate extract with dichloromethane. Eugenol in the dichloromethane extract is extract with potassium hydroxide. The eugenol in base extract is wash with dichloromethane, acidify with hydrochloric acid, extract with dichloromethane. Eugenol in dichloromethane extract is washed with distilled water, wash with sodium chloride, dry with sodium sulfate, and distill off dichloromethane. The result will be pure eugenol.