Extracting Caffeine

Obtain two uncoated alertness aid tablets and record the mass
The mass was 0.735g

Crush the two alertness aid tablets using a mortar and pestle
The mass of the crushed tablets is 0.728g

Place the crushed tablets in a beaker containing 60ml of distilled water and 8g of sodium carbonate

Heat the mixture on the hot plate.
Allow it to boil for two minutes, then turn the hot plate off and allow the contents to settle.

Carefully filter the alertness aid pill mixture into the separatory funnel. Rinse the residue remaining in the glass with a small amount of water

Allow the aqueous filtrate to cool down to room temperature as it is dangerous to add dichloromethane to a warm solution.

Add 7ml of dichloromethane to a cooled solution. The aqueous layer will be on the bottom, and the caffeine/dichloromethane will be on top, due to the density

Place the stopper in the neck of the separatory funnel and shake gently.
Invert the funnel while holding the
stopper securely in the neck, and vent the separatory funnel through the stopcock.
The caffeine will be extracted from the aqueous phase to the organic phase

Drain the organic layer into the labelled Erlenmeyer flask

Repeat this process twice to ensure that the organic layer has been completely collected
(Total of three times)

Once the extracts have been collected, add a fair amount of drying agent and let it sit in the flask for several minutes
Try to add the drying agent little by little

Decant the dichloromethane solution into a 50ml beaker, and gently evaporate the solvent away in the hood

Measure the mass of the crude product in the beaker
My mass was 0.467g

Two samples: Aqueous layer

Two samples: Organic layer

Two samples: tablet binder material and impurities that went undissolved

Two samples: Aqueous layer containing caffeine

Recrystallizing Caffeine

Add 12-15ml of cold acetone to the beaker
Warm up the beaker on the hot plate, and allow the crude product to dissolve.

Remove the Erlenmeyer flask from the hot plate and allow it to cool

With a pipet, add petroleum, one drop at a time, swirling in between drops. Continue until there is a cloudiness in the solution

Recover the recrystallized product through vacuum filtration using a Hirsch funnel

Transfer the product to filter paper and allow it to air dry for twenty minutes

Measure the mass and melting point of the recrystallized product
Final mass: 0.416g
Melting point: 231-234 degrees celcius