Isolation of Clove Oil
Objective The objective of this experiment is to perform a steam distillation using a microscale distillation apparatus and isolate a natural product from cloves. Introduction By performing steam distillation we can isolate eugenol at lower temperature than its usual boiling point of 248 degree Celsius. Eugenol belongs to a category called essential oil.
Many of these compounds are used as flavoring and perfumes and in the past were considered the essence of plant from which they were derived. Structure of eugenol (clove oil) and eugenol acetate: Reagents: Eugenol, CH2Cl2, Br2, FeCl3, Methanol
Procedure: Co-distillation We first combine 15 mL of water with 1 g of crushed, ground cloves in a 25-mL round-bottom flask. Then added a spin bar to the 25-mL round-bottom flask and assembled the microscale distillation apparatus. We made certain that the ground cloves were well wetted. We maintained the temperature of the sand bath at approximately 130 °C and wrapped the bottom of the still with aluminum foil. Then periodically transfer the distillate from the Hickman head to a 15 mL screw cap centrifuge tube and continue the steam distillation until 5–8 mL of distillate have been collected.
Then we started the extraction process by adding 2 mL of CH2Cl3 to the water–eugenol emulsion. Cap the tube and shake it frequently. We then allowed the layers to separate and transferred the CH2Cl2–eugenol solution to a clean, dry 5- mL conical vial. We made sure no water was transferred in this step. Then we added 1 mL of CH2Cl2 to the water–eugenol emulsion, cap and shake the tube. Allowed the layers to separate and transfer the CH2Cl2–eugenol solution to the 5-mL vial used previously and made certain that no water is transferred during this step.
We then added 1 mL of CH2Cl2 to the water–eugenol emulsion and shook the tube. We allowed the layers to separate and transferred the CH2Cl2–eugenol solution to the 5-mL vial used in previous step. We made certain that no water was transferred during this step. Finally we finished the co distillation process by drying the CH2Cl2–eugenol solution with 2-3 microspatulas of anhydrous sodium sulfate. Evaporation Transfer the dried CH2Cl2–eugenol solution to a clean, dry, tared, 5-mL conical vial. And rinse the drying agent with a few drops of CH2Cl2 and transfer CH2Cl2 rinse to the 5- mL conical vial.
In a fume hood, evaporate the CH2Cl2 using a hot water bath at approximately 40 °C max 55 °C. Classification Test of eugenol (clove oil) The eugenol isolated will be tested for unsaturation using the Br2Test and aromaticity with the ferric chloride test. Br2 Test First we dissolved the clove oil in 2? 3 mL of methanol then added 5 drops of clove? oil solution to a test tube. Then we added few drops of Br2 reagent and gently swirled and recorded our observations. W then prepared a control slide and matched our results to it. FeCl3 test
Dissolved the clove oil in 2? 3 mL of methanol Added 5 drops of clove? oil solution to a test tube Added a few drops of FeCl3 solution to test tube Gently swirled and record your observation Results and Calculations: Br2 test results. Original Br2 was yellow in color but when it was added to our solution it turned colorless. This shows that we had double bonds formation. Benzene gives us double bonds. Our results matched the result we obtained when we compared with control that we had created. FeCl3 test results: Our solution turned light yellowish in color.
Control was dark orange in color. Discussion: Our benzene results indicated that we had double bonds formation. Benzene gives us double bonds. Our results matched the result we obtained when we compared with control that we had created. Our FeCl3 test gave us light yellowish color solution while the control was somewhat orange. This could probably mean that we had Eugenol acetate instead of Eugenol. References: Introduction to Organic Laboratory Techniques: A Microscale Approach. Pavia, Lampman, Kriz, and Engel. (1999) Saunders College Publishing.