[bosox99]

I attempted to extract caffeine from coffee grounds using the following method:
-Measure about 25 g of coffee grounds into a filter
-Pour through ~150 ml of brine dried isopropyl alcohol
-Boil this solution until practically dry
What remained was about 2 grams of brown powder.
Anybody know what this powder contains (besides, hopefully, caffeine, and probably some salt)? Also would like to hear any other methods you know for extracting caffeine, and some methods of purifying my product?

[Yggdrasil]

Here's a protocol for the extraction of caffeine from tea that I wrote a while ago: http://www.scienceforums.net/topic/6531-caffine/?p=195207

Here's an old discussion from these forums about caffeine extraction:
http://www.chemicalforums.com/index.php?topic=7094.0

My suggestion for your protocol would be to brew coffee, and extract the caffeine into organic solvent rather than extracting everything into alcohol first.  You're probably extracting out caffeine plus a lot of water-soluble contaminants as well.