THIS PROCEDURE WILL SHOW YOU HOW MAKE CHLOROFORM FROM SIMPLE HOUSEHOLD CHEMICALS.

 

 
WARNINGS: DON'T DO THIS; IT'S VERY DANGEROUS.  APART FROM THE RISK OF INJURY FROM BLEACH THAT MAY BOIL IF YOU DON'T COOL THE REACTION PROPERLY, CHLOROFORM IS NASTY STUFF.  DO NOT INHALE CHLOROFORM FOR ANY REASON.  EVER.  DO NOT SKIP THE ICE; THE BLEACH WILL BOIL, SENDING BLEACH AND CHLOROFORM FUMES INTO THE AIR.  STORED CHLOROFORM CAN REACT TO FORM PHOSGENE, THE WWI CHEMICAL WEAPON.  DO NOT STORE CHLOROFORM IN PLASTIC OR METAL CONTAINERS.  USE SAFETY GOGGLES.


DESCRIPTION

CHLOROFORM IS A LIQUID ONCE USED AS AN ANESTHETIC, AND A SOLVENT FOR SPECIMEN PRESERVATION.  IT FINDS USES TODAY IN ORGANIC CHEMISTRY AS A SOLVENT BUT LITTLE ELSE DUE TO THE EMERGENCE OF LESS DANGEROUS ALTERNATIVES.  CHLOROFORM'S CHEMICAL FORMULA IS CHCl3 AND IT BOILS WITH SLIGHT WARMING TO 61 CELSIUS. 

CHLOROFORM CAN BE PRODUCED WITH A SIMPLE REACTION BETWEEN HYPOCHLORITE AND ACETONE.  HYPOCHLORITE CAN BE FOUND IN POOL SHOCK AND BLEACH AS SODIUM OR CALCIUM SALTS.  THE REACTION IS HIGHLY EXOTHERMIC, SO THE REACTION MUST BE KEPT COOL TO PREVENT VAPORIZATION OF THE FORMED CHLOROFORM, OR WORSE, BOILING OF THE SOLUTION.  THE FORMED CHLOROFORM IS CONTAMINATED WITH WATER AND SOME SALTS, WHICH CAN BE REMOVED BY VACUUM FILTERING AND DRYING WITH MAGNESIUM SULFATE.

CHLOROFORM PRODUCED IN THIS MANNER CAN BE USED TO SOLVENT WELD PLASTICS LIKE ACRYLIC (ANY APPLICATION WHERE DCM, DICHLOROMETHANE IS NORMALLY USED) OR TO PRESERVE SPECIMENS LIKE INSECTS.

NOTE: AS DESCRIBED THE REACTION DOES NOT PRODUCE ENOUGH CHLOROFORM FOR EXTRACTION.  YOU'LL NEED TO USE AT LEAST A GALLON OF BLEACH AT A TIME (AND SUITABLE AMOUNT OF ACETONE) IN ORDER TO RECOVER ANY USEABLE QUANTITY OF CHLOROFORM.
 

MATERIALS        

 -BLEACH OR POOL SHOCK (LIQUID)
-ACETONE (NOT NAIL POLISH REMOVER)
-ICE!!  LOTS AND LOTS OF ICE.

EQUIPMENT        

-MISC. GLASSWARE

PROCEDURE

  

WHY?

1.  ASSEMBLE YOUR MATERIALS BEFOREHAND.  MAKE SURE YOU HAVE PLENTY OF ICE, YOU'LL NEED TO REFRESH THE SUPPLY AT LEAST ONCE DURING THE REACTION.

  
2.  POUR YOUR BLEACH INTO A GLASS OR BUCKET.  I USED 1 CUP OF BLEACH WHICH IS NOT ENOUGH FOR A USEFUL REACTION. DO YOU NEED TO ASK?
3.  ADD AN EXCESS OF ICE TO THE BLEACH AND ALLOW IT TO COOL FOR 5 MINUTES.  REPLACE ANY ICE THAT MELTS. STARTING WITH COLD BLEACH CONTROLS THE TEMPERATURE LATER, AS WELL AS SLOWING THE REACTION.  BOTH ARE A GOOD IDEA IN THIS CASE.
4.  ADD ONE VOLUME OF ACETONE FOR EVERY 50 VOLUMES OF HOUSEHOLD BLEACH (THE RATIO IS 25:1 IF USING POOL SHOCK).  I USED ABOUT 5 ML OF ACETONE FOR MY 1 CUP OF BLEACH.  BE WATCHING FOR THE REACTION OVERHEATING; ADD ICE IF IT MELTS.  IN ABOUT 10 TO 20 MINUTES THE REACTION WILL BEGIN TO CLOUD UP: THE CHLOROFORM IS INSOLUBLE AND FALLS OUT OF THE SOLUTION.  IT TAKES TIME TO SETTLE, HOWEVER, WHICH MAKES THE SOLUTION APPEAR CLOUDY.
5.  WHEN THE REACTION IS NEARLY COMPLETE (20+ MINUTES), THE ENTIRE VESSEL WILL HAVE CLOUDED (SAVE FOR THE LIQUID NEAREST THE ICE) AND MOST OF THE GREENISH BLEACH COLOR WILL BE GONE. THE COLOR CHANGE INDICATES ALL THE BLEACH HAS BEEN REACTED.
6.  ALLOW THE SOLUTION TO SETTLE FOR A HALF HOUR.  IF IT STILL HASN'T SETTLED, GIVE IT A FEW STIRS.  IF YOU HAVE DONE A LARGE REACTION (1+ GALLON) THIS PROBABLY ISN'T NECESSARY. STIRRING HELPS THE CHLOROFORM DROPLETS COALESCE INTO DROPS BIG ENOUGH TO SETTLE.
7.  IN A SHORT WHILE THE CHLOROFORM WILL HAVE COLLECTED AT THE BOTTOM OF THE VESSEL.  IN SMALL REACTIONS, IT WILL APPEAR TO BE A POWDER AT THE BOTTOM.  LARGER REACTIONS WILL SEE A DUSTY / CLEAR 'BUBBLE'. SMALL REACTIONS DON'T PRODUCE ENOUGH CHLOROFORM TO PRESS ITSELF INTO A SINGLE DROP.  BYPRODUCT SALTS FROM THE REACTION CLING TO THE DROPLETS' SURFACE AND ISOLATE THEM FROM ONE ANOTHER.  A LARGE REACTION WILL PRODUCE ENOUGH GLOBULES SUCH THAT THEIR OWN WEIGHT WILL PRESS THEM INTO A SINGLE MASS.
8.  VERY CAREFULLY POUR OFF MOST OF THE REMAINING SOLUTION, BEING CAREFUL NOT TO LOOSE ANY CHLOROFORM.  
9.  EXTRACT THE CHLOROFORM WITH A SEPARATION FUNNEL OR OTHER INSTRUMENT.  DON'T USE AN EYEDROPPER; HEAT FROM YOUR BODY WILL CREATE PRESSURE IN THE DROPPER AND CAUSE CHLOROFORM TO SQUIRT OUT. THIS PICTURE SHOWS THE 'POWDER' IS ACTUALLY TINY DROPLETS OF CHLOROFORM


READER QUESTIONS

JEREMY - How would you go about storing it (besides in glass) pressurized or under vacuum? and the approximate shelf life?

ANSWER - Apart from glass you’re quite limited.  The only option would be a type of plastic that it cannot attack; I don’t know of any off hand.  Storing it pressurized offers no real advantage over storing at atmospheric pressure, but storing under vacuum is a bad idea due to the volatility.

Shelf life is short; maybe two weeks before side reactions become significant.  For longer storage it should be stabilized with methanol.

GOT A QUESTION OF YOUR OWN?  CLICK HERE TO ASK IT!