Sciencemadness Discussion Board - Failure to make Chloroform - help

Failure to make Chloroform - help

fishfrys - 22-6-2019 at 15:52

When I try to make the chloroform, after adding the acetone to the bleach carefully and wait all I have is a cloudy mixture with no chloroform at the bottom, the container becomes warm so clearly, a reaction occurs. Could any of these ingredients in the bleach interfere with the reaction?

Non-ionic surfactants
Anionic sufactants
Perfume
Limonene

thanks

[Edited on 22-6-2019 by fishfrys]

Sulaiman - 22-6-2019 at 18:10

Chloroform is soluble in water ! (about 10 g/litre)
so you need to either;
. distill-off the chloroform (I've not tried due to fear)
. use a more concentrated bleach solution. (with good cooling and patience)

wakatutu - 22-6-2019 at 18:49

The process I've employed is generally to first make a bleach slushy - you pour off enough bleach from the gallon bottle to leave room for the liquid to expand as it freezes, then put it in a freezer for about 24 hours.

Then, you add a stoichiometric amount of acetone for the concentration of your bleach (it's not hard to figure out, just calculate how many moles of NaOCl you have in your liquid and add 1/3rd the amount of moles of acetone. I usually do it all at once, then give it a vigorous shaking, and leave it in the freezer with the cap loose to prevent pressure buildup for another 24 hours.

At this point, the aqueous layer is completely transparent and colorless, and the organic layer is readily accessed. I would definitely recommend distilling it afterward because there will be some things in there that are not chloroform.

Metacelsus - 23-6-2019 at 01:25

Quote: Originally posted by fishfrys

When I try to make the chloroform, after adding the acetone to the bleach carefully and wait all I have is a cloudy mixture with no chloroform at the bottom, the container becomes warm so clearly, a reaction occurs. Could any of these ingredients in the bleach interfere with the reaction?

Non-ionic surfactants
Anionic sufactants
Perfume
Limonene

Yeah, the surfactants will definitely mess it up. Distillation is your only option, but watch out for foam. You might just want to start over with pure bleach.

draculic acid69 - 23-6-2019 at 03:22

Bottled bleach is fine for tiny amounts of chloroform but if you want a decent amount
(More than 20ml) you need to switch to 10% pool chlorine and if you want more than a cup start with calcium hypochlorite.usually the cheapest no name brand of bleach is the best as it has no additives

[Edited on 23-6-2019 by draculic acid69]

Sulaiman - 23-6-2019 at 03:37

I have successfully used 35% sodium hypochlorite to make a small quantity of chloroform,

what is the (relative) benefit of using calcium hypochlorite ?

EDIT: the hypochlorite solution was not 35%, more like 14% to 15% ...

[Edited on 23-6-2019 by Sulaiman]

fusso - 23-6-2019 at 03:58

is 35% Na hypochlorite really a thing?

Boffis - 23-6-2019 at 04:42

If your bleach is dilute (less than 10%) try adding salt to the reaction mixture to reduce the solubility of chloroform in water. Also remember that commercial bleach contains excess NaOH which will hydrolyse the chloroform if the mixture becomes too hot.

[Edited on 23-6-2019 by Boffis]

Sulaiman - 23-6-2019 at 07:17

Quote: Originally posted by fusso

is 35% Na hypochlorite really a thing?

Probably not

Sorry, I had a brain fart,
I just checked and what I used was
"Sodium hypochlorite, 14%-15% chlorine eq."

Well caught !

XeonTheMGPony - 23-6-2019 at 07:19

Dairy uses 22% solution, so try looking at some industrial cleaner suppliers or local agricultural suppliers

Ubya - 23-6-2019 at 10:26

the surfactants clearly are the culprit. use bleach with no additives, and the more concentrated is the bleach the better

Swinfi2 - 23-6-2019 at 15:58

Tried this with the cheapest bleach available in asda (england) and all I got was cloudy gelatinous... Not chloroform. How best to dispose of chlorinated waste?

I'm thinking of making a hypochlorite/chlorate cell to make some relatively concentrated hypochlorite and start there but I need to get a regulated power supply first. Every electrochemical experiment f**ks up on me and eats the electrodes...

draculic acid69 - 23-6-2019 at 21:50

The reason for using caocl is price and concentration.bleach is 5%naocl isn't it and pool chlorine is 10%naocl,with caocl it can be more concentrated.ive never seen naocl at more than 10-11% .

Ubya - 24-6-2019 at 02:05

Quote: Originally posted by Swinfi2

How best to dispose of chlorinated waste?

add a sodium hydroxide solution to the chloroform emulsion/solution, let it react for as long as possible (a fee days?) then you can drain it in the sink (the end products should be formate and chloride)

Keras - 24-6-2019 at 05:06

Quote: Originally posted by Ubya

Quote: Originally posted by Swinfi2

How best to dispose of chlorinated waste?

Can’t you treat the waste with hydrogen peroxide? It should oxidise the Cl- ion into free Cl2 and after a few hours you can safely dispose of the rest?

[Edited on 24-6-2019 by Keras]

Ubya - 24-6-2019 at 05:14

Quote: Originally posted by Keras

Quote: Originally posted by Ubya

Quote: Originally posted by Swinfi2

How best to dispose of chlorinated waste?

add a sodium hydroxide solution to the chloroform emulsion/solution, let it react for as long as possible (a few days?) then you can drain it in the sink (the end products should be formate and chloride)

Can’t you treat the waste with hydrogen peroxide. It should oxidise the Cl- ion into free Cl2 and after a few hours you can safely dispose of the rest?

Only at really low ph chloride is oxidized by concentrated hydrogen peroxide, in basic solution nothing happens. Plus, chlorides are not a concern, why bothering to make nasty Cl2 gas to remove them?

Keras - 24-6-2019 at 05:46

I was just attempting to suggest something in the vein of Fenton's reagent. But you may well be right.

Buon pomeriggio nel caput mundi!