Presentation on theme: "EXTRACTING ORGANIC CAFFEINE IN A SMALL ROOM Martin the Morph-Man."— Presentation transcript:
EXTRACTING ORGANIC CAFFEINE IN A SMALL ROOM Martin the Morph-Man
Overview Caffeine may be isolated from coffee, tea and other aqueous solutions by a simple acid-base extraction procedure
Disclaimer It is legal to extract compounds (e.g. caffeine) from a wide range of natural sources It is NOT legal to extract compounds from some other sources, nor to possess those compounds obtained by any means This talk is for your general interest only You are urged NOT to apply the following procedures to any natural products You are encouraged to be aware of the legal implications of any extraction procedures performed without legal sanction
Theory : Caffeine and Alkaloid Chemistry Alkaloids are heterocyclic organic compounds - ring containing carbon and nitrogen May contain (non-ring) oxygen N and O confer acid/base properties Acid/base properties influence solubility in various solvents
Theory: Acid-Base Extractions Generally: N-atoms are charged positive in acid conditions and are neutral in basic (alkaline) conditions O-atoms are neutral in acid conditions and are charged negative in basic conditions Charged compounds are more soluble in polar solvents such as water & methanol Neutral compounds are more soluble in non-polar solvents such as ether and toluene
Target compound NAME :Caffeine CHEMICAL NAME :3,7-Dihydro-1,3,7-trimethyl-1H-purine-2,6-dione ALTERNATE CHEMICAL NAMES :1,3,7-trimethylxanthine; 1,3,7-trimethyl-2,6-dioxopurine; coffeine ALTERNATE NAMES :thein; guaranine; methyltheobromine; No-Doz CHEMICAL FORMULA:C 8 H 10 N 4 O 2 MOLECULAR WEIGHT:194.19 APPEARANCE:White hexagonal or needle-like crystals MELTING POINT:238ºC SOLUBILITY:Water, Ethanol, Methanol, Acetone, Chloroform LD50 Dog:140mg/kg oral LD50 Rat:105mg/kg IV LD Low (Lethal Dose):Human deaths reported at less than 4 grams oral.
Technique 1) Cook up 2) Clarify 3) Remove fatty impurities 4) Make solution alkaline 5) Extract alkaloids to organic solvent 6) Separate organic from aqueous phase 7) Repeat extraction to solvent (steps 5&6) 8) Dry organic solvent 9) Evaporate organic solvent 10) Purify compound by recrystallisation, often from another organic solvent