Sciencemadness Discussion Board - Haloform with IPA

Haloform with IPA

Little_Ghost_again - 17-9-2014 at 09:03

Hi
First a correction from a post I made a couple of weeks ago.
I stated the sodium hypochlorite I had was 13%, turns out if you read the small print its actually 10%.
Anyway.........
After consultation here it was sugestead I get a small beaker of the chlorite and add a few drops of IPA to see what happens.

I have now done this and the result...... NOTHING. No heat no reaction no any thing.
This was a nearly full 20 ltr container I got my beaker full from, but from the moment I opened the container I had a feeling it was a dead duck, normally I hate the smell of bleach. This had hardly any smell at all, it had the correct piss like colour but hardly any bleach smell.
I have a vague memory reading somewhere that bleach is temperature sensitive and if it is kept too warm it degrades into.......something else. The building this was kept in did get warm over the summer, so am I to assume this has now rendered it useless for this reaction? Or maybe IPA isnt going to work??
Personally I think its the storage of the hyperchlorite that was wrong and it got too warm for too long. I can get some more I guess, but time to save up again!
Before I start using this neat for cleaning down the pig house are my assumptions correct?

LG

bbartlog - 17-9-2014 at 09:57

Sodium hypochlorite solution does degrade over time, primarily by way of

3NaOCl -> 2NaCl + NaClO₃, but also some decomposition to just NaCl + O₂ occurs.

However this is a gradual process that slows as the concentration decreases, and probably doesn't account for your lack of reaction.

I also tried this combination many years ago and observed no change. However, all of the lab preps I have seen since then for oxidizing secondary alcohols with bleach use acetic acid as well (or a catalyst). See here: http://www.umich.edu/~chem216/216%20S11-Expt%202.pdf

As you can see the acetic acid is present in excess. It appears based on the mechanism outlined in the abovelinked pdf that the issue is simply that hypochlorous acid (HOCl) is the necessary agent of oxidation here, and that it isn't present as such in appreciable quantities in commercial bleach, which would be quite basic even if it didn't have added NaOH to stabilize it. Hence the need for acidification.

Little_Ghost_again - 17-9-2014 at 12:09

Quote: Originally posted by bbartlog

Sodium hypochlorite solution does degrade over time, primarily by way of

3NaOCl -> 2NaCl + NaClO₃, but also some decomposition to just NaCl + O₂ occurs.

However this is a gradual process that slows as the concentration decreases, and probably doesn't account for your lack of reaction.

I also tried this combination many years ago and observed no change. However, all of the lab preps I have seen since then for oxidizing secondary alcohols with bleach use acetic acid as well (or a catalyst). See here: http://www.umich.edu/~chem216/216%20S11-Expt%202.pdf

As you can see the acetic acid is present in excess. It appears based on the mechanism outlined in the abovelinked pdf that the issue is simply that hypochlorous acid (HOCl) is the necessary agent of oxidation here, and that it isn't present as such in appreciable quantities in commercial bleach, which would be quite basic even if it didn't have added NaOH to stabilize it. Hence the need for acidification.

My main concern was this stuff normally stinks!! I hate the smell, but tonight I could hardly detect any bleach like smell.
Fortunately we use loads of this stuff, so it will be used with less dilution than normal. I will wait until dad gets some more and use some fresh stuff. I will also try the acetic acid.
I prefer that to the easy option of changing solvent, Full report back on results and many thanks for the info
LG

Amos - 17-9-2014 at 16:06

For the record, a few drops isn't going to cut it. Chloroform is somewhat soluble in water, and the yield is lower than you'd think. You won't get that much of a warming reaction either with small amounts(and it also takes some time to initiate). I'm going to try the same thing tonight to see if maybe it works with bleach of a confirmed purity, in case yours has gone bad.

Amos - 17-9-2014 at 20:09

Okay, so I tried my own haloform reaction with IPA to see if your results were correct, Little Ghost. I chilled 100ml of 8.25% NaClO to nearly freezing, added 10ml of dry isopropanol, and left it alone for a bit. Five minutes later, the liquid was cloudy, but there was no separation of layers and it wasn't any warmer than 5 minutes at room temperature would make it. I tried adding 2 ml glacial acetic acid to catalyze the reaction. All I got was a whiff of chlorine; no reaction seems to have taken place the whole time.

bbartlog - 17-9-2014 at 20:30

2ml of glacial acetic acid is not enough to acidify 100ml of 8.25% bleach, and you have too much isopropanol for the haloform reaction to complete.

Oxidation to acetone would roughly deplete the hypochlorite, with none left for the rest of the reaction. You have approximately 125mmol of NaOCl there (and there is a little added NaOH to make it more alkaline, too). If you want to do the haloform reaction starting from IPA, you need a 4:1 mole ratio of NaOCl to IPA, so you would only be looking at 2.3 ml of IPA (30mmol). And you would want maybe 150-200mmol of acetic acid, i.e. something more like 10-12ml (but even that might not be enough ... maybe try one of the published preparations??).

You will waste a lot less time if you do some stoichiometric calculation beforehand.

[Edited on 18-9-2014 by bbartlog]

[Edited on 18-9-2014 by bbartlog]

Little_Ghost_again - 17-9-2014 at 22:28

thanks guys.
We will be getting some more soon, mine didnt go cloudy! I will also grab some acetic acid.
I am determined to get it work

Little_Ghost_again - 17-9-2014 at 23:33

WELL UPDATE!!!!

I know I shouldnt do things the way I do, but this was just a test.........

The beaker was just a test, the idea was put a little IPA in a Beaker of hypochlorite and see if it got hot.
Well it didnt.
So last night I thought I would 'just see' if adding Sodium hydroxide would salt out the IPA.
I will post pics after School but I am not sure what I have................................
The beaker is a clittle cloudy but there are clear droplets on the bottom of the beaker that dont look like IPA (kind of too shiny).
Obviously I have no idea how much IPA or Hydroxide I added

. It was a kind of I wonder what sort of thing..... OK I foofed up I didnt measure and I should have full stop.
Actually I will go take a pic now, I guess best way is decant everything into a sep funnel. Now I am not convinced this is anything but IPA on the bottom, but the beaker smells different this morning, it smells slightly sweet. BRB with a pic

Little_Ghost_again - 17-9-2014 at 23:49

Well the pic is rubbish, but the spot in it is very clear and shiny in real life, it didnt come out too good in the pic, I took a little off the bottom via pipette and it is definitely NOT IPA!!
I have never smelled Chloroform but dad has and he says he is sure that it what it is, its very sweet smelling

. So tonight I will try and recreate (why the foof dont I do it right the first time). All I had to do was measure!
Anyway try adding some hyperchlorite crystals (just a few) and leave.

Little_Ghost_again - 18-9-2014 at 00:43

Well late for School!
Did one other quick experiment, I was almost convinced that it was just IPA salted out with the added Hydroxide, so I added a drop more hydroxide and more IPA, its gone slightly cloudy again (not as much), BUT the IPA is sitting in a nice clear layer on the TOP!!!!
So surely the bottom blob of sparkly clear liquid is chloroform? What I dont get is the bleach had hardly any smell, no heat was detected, nothing happened at all until I added a small amount of sodium hydroxide, the hydroxide I added was some of the liquid from the crystals that had melted in the air.
I am So annoyed I just did a 'quick test'.
So tonight I will use hypochlorite from the same drum as before, and this time weigh and measure everything. Hopefully I can get it to work again.
How do you test for Chloroform?
So far all I have done is place 3 drips from a burette into a watch glass and 3 drips of IPA into another.
The blob evaporated way way quicker than the IPA.

Amos - 18-9-2014 at 04:15

Quote: Originally posted by bbartlog

2ml of glacial acetic acid is not enough to acidify 100ml of 8.25% bleach, and you have too much isopropanol for the haloform reaction to complete.

Oxidation to acetone would roughly deplete the hypochlorite, with none left for the rest of the reaction. You have approximately 125mmol of NaOCl there (and there is a little added NaOH to make it more alkaline, too). If you want to do the haloform reaction starting from IPA, you need a 4:1 mole ratio of NaOCl to IPA, so you would only be looking at 2.3 ml of IPA (30mmol). And you would want maybe 150-200mmol of acetic acid, i.e. something more like 10-12ml (but even that might not be enough ... maybe try one of the published preparations??).

You will waste a lot less time if you do some stoichiometric calculation beforehand.

[Edited on 18-9-2014 by bbartlog]

[Edited on 18-9-2014 by bbartlog]

Well I wasn't trying to produce chloroform for use(I've got enough of that already, believe me), though I admit it was poorly executed. I wanted to see if it was a more-or-less straightforward reaction like that of acetone, and follow steps similar to Little Ghosts's first attempt(because he was concerned something was off with his bleach). Unfortunately I didn't read your post all the way through, or I would've known to completely acidify the mixture, which would've required calculations and ultimately probably would've lead to success.

Amos - 18-9-2014 at 04:25

Quote: Originally posted by Little_Ghost_again

So tonight I will use hypochlorite from the same drum as before, and this time weigh and measure everything. Hopefully I can get it to work again.
How do you test for Chloroform?
So far all I have done is place 3 drips from a burette into a watch glass and 3 drips of IPA into another.
The blob evaporated way way quicker than the IPA.

For someone that hasn't dealt with chloroform, the way you describe it definitely sounds like your reaction worked! The lack of warming is strange, though; even when I've used frozen sodium hypochlorite in the past the reaction vessel became warm, almost hot to the touch. I think I'm going to try to redo it with the proper figures using simple household vinegar instead of glacial, that way it may actually be a functional synthesis for those that can't get their hands on acetone or GAA.

Praxichys - 18-9-2014 at 05:01

Since hypochlorite solutions are sold at low concentrations to help reduce decomposition, it is only making a bad yield worse by relying on hypochlorite to both oxidize the isopropanol to acetone and then generate chloroform from the acetone.

My advise: find some acetone! There is no need to acidify - just add the stoicheometric amount of acetone in two portions to a frozen jug of (I use 12.5%) NaClO solution, with re-freezing between additions. (Be careful - this is VERY exothermic - it takes about 90 seconds to go from frozen to warm. Adding it all at once DOES result in boiling) Let it warm to room temperature, and there will be a mess of chloroform beads on the bottom. Pour off ~90% the waste, then use a sep funnel to finish out the separation. Dry the chloroform over MgSO4 and distill.

Each gallon is going to give you something like 180ml of chloroform after losses, even if you do it sloppy and quickly like I do.

That said, I can make a liter of chloroform in an afternoon, at the cost of about $18. Check out my YouTube video.

Little_Ghost_again - 18-9-2014 at 07:09

Ok back from School, Before I left this morning I added a little more IPA, it clearly floated on the top in a layer 2 cm deep. Soooo I added more bleach and a drop more sodium Hydroxide.
The sodium hydroxide was actually the solution that was in a bowl from some sodium hydroxide crystals that had been left in the air.

I am totally sure the hypochlorite isnt as good as it was, a quick test and not conclusive but.... I had a T shirt that was splashed several months ago from this very drum, within moments it had bleached the colour out. So i got same T shirt (It's a favorite so I kept it) and dropped several drips on the T shirt.
The colour did bleach out but took ages and isnt as white!

Anyway....................
The moment I added the sodium hydroxide the IPA layer went and the solution became cloudy, I have had a electronic data logger on the beaker all day. after 26 mins this morning the beaker rose 3C from room temp, it has remained 3c higher all day and is still cloudy.

I am going to weigh and redo the whole thing later, but The whole point of this was to try without acetone. Nothing at all happened to the solution until I added the sodium hydroxide. I have no idea what that has to do with the reaction, I added it simply to see what would happen. To be honest my thinking went like this...... Ok hyperchlorite solution foofed, so probably now contains water/saltwater.
If it contains water then I can add some hydroxide and feel the heat from the reaction of sodium hydroxide with water, if its salt water then there is a chance sodium chloride with drop out as crystals (ive been playing with salt).
To my surprise none of that happened! instead my clear bleach/IPA solution went cloudy, I went to bed last night and left it like that. This morning I got up and the solution was almost clear with this really clear blob on the bottom of the beaker.
Now there was only around 300 ml in the beaker, so the size of blob made me think it was IPA. Mainly because it seems alot of chloroform from what I am pretty sure is now weakish bleach.

I have no idea what ratio's to use or anything, but at this point I dont want to know. instead I am going to do it by eye but measure the amounts. I will update later.
The pic was taken in a hurry and against a non white wall, it dosnt show how clear and sparkly the blob is. Also it smelled really sweet and a bit sickly, I am not sure I like the smell but its certainly wasnt IPA.
Also I put a drop on a watch glass and it evaporated much faster than a drop of IPA i put on another one.

Little_Ghost_again - 18-9-2014 at 07:13

I didnt add any acid! I might do one with some vinegar and citric acid (its all I have ).
I will report back later

Little_Ghost_again - 18-9-2014 at 08:10

Ok I scaled up a little bit.

502g of sodium hypochlorite
102g of IPA
90g of Sodium hydroxide

The hypochlorite

The ipa

The Hydroxide

this next pic is the hypochlorite mixed in with the IPA and shaken well, all chems at room temp (15.1c). Look close you might see the distinct layer of IPA on top

Then I waited 15 mins with no change and added the sodium hydroxide, this is the next pic

It began to cloud straight away and temp after 5 mins rose to 25.2C and so far is stuck there, I will take the temp as and when I can and report any changes.
As a side note the beaker I left this morning is now looking like this

What you cant seee in the pic is more beads of hopefully chloroform that are on the bottom, the beaker is sat at 18C

Amos - 18-9-2014 at 08:20

Normally, I'd say your addition of sodium hydroxide to the mix may have salted out the IPA you added; traditionally that's what you'd use if you wanted to remove the water from IPA. But the Isopropanol in that case would float to the TOP. If you've got something in there DENSER than water, I'm inclined to say you might've made chloroform, especially that note you made about how much clearer/shinier it was.

Here's a picture I took with the more typical acetone/hypochlorite haloform reaction, if this is what yours looks like I'd say you've got what you were after: http://sciencemadness.wikia.com/wiki/Chloroform?file=Chlorof...

Quote: Originally posted by Praxichys

Since hypochlorite solutions are sold at low concentrations to help reduce decomposition, it is only making a bad yield worse by relying on hypochlorite to both oxidize the isopropanol to acetone and then generate chloroform from the acetone.

My advise: find some acetone! There is no need to acidify - just add the stoicheometric amount of acetone in two portions to a frozen jug of (I use 12.5%) NaClO solution, with re-freezing between additions. (Be careful - this is VERY exothermic - it takes about 90 seconds to go from frozen to warm. Adding it all at once DOES result in boiling) Let it warm to room temperature, and there will be a mess of chloroform beads on the bottom. Pour off ~90% the waste, then use a sep funnel to finish out the separation. Dry the chloroform over MgSO4 and distill.

Each gallon is going to give you something like 180ml of chloroform after losses, even if you do it sloppy and quickly like I do.

That said, I can make a liter of chloroform in an afternoon, at the cost of about $18. Check out my YouTube video.

I did check your video, by the way(https://www.youtube.com/watch?v=37m_kMK7Po0), but you said in the video you only got about 100ml per gallon of sodium hypochlorite solution, which is kind of far away from 180ml. I'm not saying this to tell you that you're wrong; rather, I was wondering if the number you gave was a mistake, or if there's something different you're doing currently that gives you a higher yield? Using 8.25% NaClO I typically get about 70-80ml per jug.

Little_Ghost_again - 18-9-2014 at 09:05

Quote: Originally posted by No Tears Only Dreams Now

Normally, I'd say your addition of sodium hydroxide to the mix may have salted out the IPA you added; traditionally that's what you'd use if you wanted to remove the water from IPA. But the Isopropanol in that case would float to the TOP. If you've got something in there DENSER than water, I'm inclined to say you might've made chloroform, especially that note you made about how much clearer/shinier it was.

Here's a picture I took with the more typical acetone/hypochlorite haloform reaction, if this is what yours looks like I'd say you've got what you were after: http://sciencemadness.wikia.com/wiki/Chloroform?file=Chlorof...

Quote: Originally posted by Praxichys

Wow looks like thats it! your pic like mine dosnt exactly show how....sparkly and blueish it can make the light (I cant think how to describe it), but I am sure its the same.

UPDATE
Things didnt look right and temperature dropped to 20c, so I added another 1050g of hypochlorite. Temp gone back up to 25c.

I have put the beaker solution (most of it) into a sep funnel, its still reacting slightly and the temp is 18.9c room temp 15.2c
Here is a pic of it, again the pic dosnt do it justice, my problem with the camera is its set on RAW files (its not mine), its a Nikon D7000 so the files should be tweaked first in photoshop or the camera placed in JPEG mode.
I dont know how to do that. so I take a pic then do a screen shot of the file after loading it into the laptop, so you see a screen shot of a RAW file with no colour compensation, I will get dad to take the pics later its his camera. Then you can see what I mean by shiny.
Anyway considering its still going and the beaker is only 400ml, If it is Chloroform then the yield to me seems good, especially as the hypochlorite isnt the 10% it should be.
Is there anyway for me to titrate the strength with a acid like citric? I dont have much in the way of acids yet. in fact until I sort proper locked cupboards my chemicals are limited

Little_Ghost_again - 18-9-2014 at 09:16

I am 100% its not IPA. It might not be Chloroform but its certainly Not IPA, if you add IPA to a small amount of liquid from the original beaker then it floats. Plus IPA isnt sparkly, Also it moves almost like a blob! if you shake it then it separates into tiny beads that quickly find each other, it dosnt sit in a layer in the beaker its more of a slight dome (blob is the only way I can think of it).

EDIT!!!

Dads just got home with 50ml of chloroform from work and some drosophila melanagasta (fruit flies to you and me).

He used it to knock them out and they recovered in the same amount of time as the lab grade Chloroform. We tried knocking some out with IPA.....
If they were bigger I would dig a hole for them! So apart from how it looks, it knocks out fruit flies and they can recover, the time to knock them out is the same (roughly) as the lab stuff.

I am well Chuffed. Beaming in fact

[Edited on 18-9-2014 by Little_Ghost_again]

Actinium - 18-9-2014 at 10:14

just had a question since we are on the topic?
I wanted to try the Haloform and wanted to use acetone with the 3:1 ratio. Is it crucial to round up/down when figuring molarity? I can't exactly remember where I read it on one of the posts on this board that even slight excess of acetone isn't helpful but actually counter productive?
I ask because I'm second guessing myself on my calculations and wanted to know if I was say, 1/2ml-1ml under stoichiometric amounts with the Acetone, would the reaction still proceed?

aga - 18-9-2014 at 10:15

Congratulations !

Your post spurred me to try the haloform reaction too, with acetone.

Today there is a pea-sized drop of something Clear in the bottom of a beaker.

Also 4 other beakers with various quantities of acetone to see what happens.

No fruit flies to titrate it with though.

Little_Ghost_again - 18-9-2014 at 10:28

When I get acetone I will try with that. I will see tomorrow what I get with this new batch. If I get another result then I need to learn how to work out Mols etc and start experimenting, what I like so far is in the first beaker I did I hardly used any IPA, the hypochlorite is meant to be 10% but without doubt it has degraded.
I use this brand a great deal at home because my jobs include cleaning out various animal buildings etc and when I clean other peoples tractors they get the wheels etc sprayed first at the bottom of the drive way (bio security). So I know how it normally smells and it is way way stronger than this one. Its made by a good company (Diversey lever), this drum was at the very back of a building and had previously been opened and part used.
The building got used to store some equipment and it made it hard to get to the drum, so it got left there and I used other drums. I could do with knowing if I can titrate the hypo with a acid like citric. That way I can tell what the yield is.
I think the yield has been good considering all the factors, also I havnt had to cool anything! everything has started at around 15c and so far not gone over 25c.
Anyway is alot of fun experimenting with!

aga - 18-9-2014 at 11:06

Mols are pretty straighforward.

Best to think of a simple example, have a go at working out yourself, then start a new thread about that.

You'll 'Get It' in minutes, and then forevermore be able to work out the stoichometric amounts for any reaction.

Little_Ghost_again - 18-9-2014 at 11:56

UPDATE

Temperature risen to 28.9c (all temps taken with IR temp gun). I have a 2 Ltr conical flask with a cotton wool stopper.
Flask gently swirled 4-5 times, stopper removed and contents sniffed (wafted). Strange smell............ IPA I would describe as a Blunt/rough kind of smell and very distinctive, this smell from the flask dosnt smell like chloroform (yet) and no droplets of chloroform are visible, however the smell has a much more sweet/sickly smell that I would describe as aromatic and lingering, it leaves a taste in the back of the throat for a fairly long time >10 mins.
Smells volatile and unlike IPA is apparent as soon as the flask is opened.

While I am pretty sure this will give chloroform in the end, I want to redo tomorrow and remove a few more unknowns. For example the hydroxide liquid is a few days old and is simply sodium hydroxide prills that have reacted with the air, no water has been added intentionally.
So I have no idea of the composition of this liquid and no idea of concentration etc.
Tomorrow when I repeat I will use dry prills and make a solution (molar strength undecided at this point) .

I would really appreciate some help tomorrow in working out what reactions are taking place and what the end products are likely to be. Apart from the target compound (Chloroform) I am interested if anything else can be extracted from the liquid that is decanted from the Chloroform.
I am reading up on equations etc but at present I am at a very early stage in understanding. I know this amount of hand holding is a PITA, but it would be really appreciated

.

I dont need it for this current experiment, this was more to do with seeing if I could repeat last nights.

I am also looking into how I can calculate the strength of hypochlorite as it is, in its current form.
It is a fascinating process, I am surprised at the lack of heat, I would have expected far more, even if purely from adding hydroxide. If I can get this working correctly and a decent yield then for me its a better way than Acetone. It also seems to not require any form of temperature control (so far).

aga - 18-9-2014 at 13:05

IR temp guns aren't too reliable.

I got one, and thought it was Ace until i got a few mercury and alcohol thermometers.

For your next Haloform, do the maths first as bbartlog suggested.

It's true what bbartlog says: it saves a hell of a lot of time when you know the correct amounts of reactants.

As i understand it, this Haloform reaction is multi-step and more complicated than A+B = C.

For working out the required quantities (AKA stoichimetry) all you need is the Reactants (chemicals before reacting them together) and the Products (stuff you wanna make).

Having to have the right environment, and needing NaOH as well complicates it a bit.

Need help from an OC chemist here who knows this reaction, and can give you the Formula so you can do the stoichiometric calculations.

Anybody ?

P.S. pronunciation guide :-
stoichimetry = Stoy-ee Kim Ettry
stoichiometric = Stoy Key O Metric.

It's all just Greek and Latin to keep us all confused all the time, and keep uneducated plebs out.

E.g. 'Hydro Gen' is ancient Greek for 'Water Creator', etymylogically.

'Etymology' is also derived from ancient Greek, originally meaning Truth, then Seeker of truth, and altered via French then into English to mean 'The [truth of the] Origin of a Word'.

All specialist fields have their own sub-languages.
The Posher ones use Greek and Latin, the Peasant ones make up new words, like 'spindle'.

Amos - 18-9-2014 at 18:20

Quote: Originally posted by Little_Ghost_again

UPDATE

Temperature risen to 28.9c (all temps taken with IR temp gun). I have a 2 Ltr conical flask with a cotton wool stopper.
Flask gently swirled 4-5 times, stopper removed and contents sniffed (wafted). Strange smell............ IPA I would describe as a Blunt/rough kind of smell and very distinctive, this smell from the flask dosnt smell like chloroform (yet) and no droplets of chloroform are visible, however the smell has a much more sweet/sickly smell that I would describe as aromatic and lingering, it leaves a taste in the back of the throat for a fairly long time >10 mins.
Smells volatile and unlike IPA is apparent as soon as the flask is opened.

While I am pretty sure this will give chloroform in the end, I want to redo tomorrow and remove a few more unknowns. For example the hydroxide liquid is a few days old and is simply sodium hydroxide prills that have reacted with the air, no water has been added intentionally.
So I have no idea of the composition of this liquid and no idea of concentration etc.
Tomorrow when I repeat I will use dry prills and make a solution (molar strength undecided at this point) .

I would really appreciate some help tomorrow in working out what reactions are taking place and what the end products are likely to be. Apart from the target compound (Chloroform) I am interested if anything else can be extracted from the liquid that is decanted from the Chloroform.
I am reading up on equations etc but at present I am at a very early stage in understanding. I know this amount of hand holding is a PITA, but it would be really appreciated

Okay, I did warn you about this before, but now that you're working with such large amounts of your reactants, you need to be cautious about how much chloroform vapor you allow into the air and how long you leave these things out. Oxygen and light will convert it to phosgene, which is amongst the biggest hazards you can encounter in a home chemistry setting(as far as I know, anyway).

As for you, Actinium, my first couple of haloform reactions were not all that precise(I might've even measured by eye the amount of acetone to use without even weighing it) and there wasn't a huge jump in the amount of chloroform I got when I started being more serious with my calculations.

Little_Ghost_again - 18-9-2014 at 23:36

Quote: Originally posted by No Tears Only Dreams Now

Quote: Originally posted by Little_Ghost_again

The flask is now sealed, I will weigh the product from this batch and dispose (it isnt a huge yield).
I currently have more questions than answers!

For example

Because we had the referendum in Scotland last night, everyone stayed up until 4am. During that time the flask started to loose the yellow tinge and star to clear, there was some chloroform in the flask so I added 100g of hypochlorite. I could see chloroform begin to bead and form straight away.
Temperature was 31c in flask and 13c in room. I Added another 50g of hypochlorite before bed and again chloroform appeared to drop out almost straight away.

This morning the solution has gone a slightly cloudy very pale milk like colour, temp of flask 18.9c, room 15c.No yellow tinge, so added 20g hypochlorite.
not much happening and certainly no chloroform dropping straight out. SoI am guessing reaction is about done.

I will leave until 4pm when I get in from School. Then separate to measure Chloroform, I am guessing roughly 80ml from just over 2 ltr of solution.
Yield not great on one hand but then again I dont actually know starting concentration of this batch, I am pretty sure it had degraded.
I would like to see if I can some measure the concentration of hypochlorite in the tub. My gut feeling is the concentration is going to be a lot lower than the 10% it was meant to be.
In that case the yield would be pretty good, I havnt used much IPA in this reaction so, I will be trying again soon. I will wait until I have some Ethanol and amber reagent bottle to store the chloroform in.

If when I get home the solution is milky clear again then I will decant off and mess with that

. I am interested in what it might contain.

Its definitely worth doing again, the reaction never went above 33c even starting from room temp solutions, no cooling at all used or needed. A very small amount of solvent used (Under a Ltr).

So how do I titrate the contents on the bleach barrel? only acids I have are citric and vinegar! I can order some and some indicator solution.
I am guessing I make a 1M solution of Acid and titrate say 100ml of bleach until end point, then calculate (will read all this up first) from there.

If all the hypochlorate has been used up and all the IPA then what products are likely to be left?
If its salt then I would try and recover some (no reason, just something I want to try).
BUT none of this will happen until I have an idea of what reactions likely took place and what I am likely to have left over in the waste solution.
How long roughly before phosgene etc is likely to be a problem? If its >24hours then I will wait until later tonight to dispose of. While at School the flask is sealed with clear food rap and elastic band (seems to have cause a very slight vacuum). Flask will be put into a cupboard.

EXCEPT

I have forgotten its friday so home by 11am today

.

Anyway for safety this project will put on the back burner until I have more info and better storage etc

Little_Ghost_again - 19-9-2014 at 07:37

Ok had a few problems sorting it out lol.
Anyway I ended up with 110ml !! its really strange stuff, kind of sticks to the sides of glassware even in a liquid, then as soon as another blob touches it they fall to the bottom! turn the sep funnel upside down once or twice and it all falls to the bottom!
Anyway looks like it worked for sure!!! So as soon as my Ethanol is ready and my amber bottles are here I will make some more

. I can get IPA a fair bit cheaper than acetone so that will be handy!
Havnt had the heart to clear up yet

. But I guess for safety better I get rid for now.
So for now thats the end of my experiment, but I will come back to this one again

Amos - 19-9-2014 at 07:55

I was going to tell you that you could try stabilizing chloroform with isopropanol instead of ethanol and just keeping it out of sunlight. My container(it is amber glass) is kept pretty full to keep gas from building up on top, just in case the IPA doesn't work. Someone that has experience with chloroform or with the chemistry of stabilizing it: Could one use isopropanol instead of ethanol? Phosgene is supposed to decompose in the presence of "alcohols" (that's all it says), so I'd assume it would work.

Little_Ghost_again - 19-9-2014 at 09:55

Its ok its all gone now, I wanted to try and see if I could use IPA and get a decent yield. I am happy that I can do that, I want to find the strength of the hypochlorite as the yield was actually a lot higher than I expected. I also dont understand how it can work so well and yet produce so little heat.
Anyway I will be doing it again soon and my Ethanol will be ready to distill soon.

Little_Ghost_again - 20-9-2014 at 03:45

I thought that was the end of it!
I kept back the waste water from the reaction, the idea being once I had the knowledge to work out the reactions that had taken place I would know what was in it.
I couldnt resist trying things out though...................... So yesterday I added 230 ml of it to a sep funnel and added a pinch of table salt. I did this because as the pics show the waste is cloudy, I wondered if salt would cause anything to drop out of make the solution clearer.
This morning I have a layer at the top of clear liquid, there is around 50-60ml. I have no idea (yet) what it is, the smell is similar to IPA but not exactly, so it could be an azeotrope of the IPA I used and water from the reaction, but that dosnt make much sense, I didnt use much IPA so I am surprised there is so much of this after I got a good yield of Chloroform.
I will leave this another 24 hours then separate. Some of it I will put in a flask and maybe add sodium hydroxide, the idea being to see if I can draw any water out of it.
Some I will distill and see what temperature the distillate comes out over. First I will see if there is any sodium hydroxide in it because I dont want to distill and freeze and joints! So I will test a little with some acid.
I might even have a go at adding citric acid to some in a flask then distill it and see what comes over.

byko3y - 29-4-2015 at 00:47

I've tried to make chloroform (after failing to produce acetone) using OTC NaOCl solution.
I've measured NaOCl content to be 1.8%, but I doubt it contains only the hypochlorite.
So, I took a flask with 300 ml of this solution, which is slightly green, and slowly poured few ml of isopropanol. Nothing happened, so I though it's a good idea to add 5g of NaOH to it.
Still nothing happened, the solution remained slightly green and had an odor of IPA. Then I heated it for unknown amount of time (less than hour), and later on distillation I got my IPa back (maybe there's some chloroform in it). In the source flask I noticed some precipitate, and went like "wtf, there should be not precipitate".
I really think my hypochlorite is not a hypochlorite in fact, because when I tried to acidify it, the smell of chlorine was really horrible, though it might have been not a Cl2.

Left - solution before heating, pale green color. Right - solution after heating and filtering off a white precipitate, totaly colorless.
I think the precipitate is NaCl, old hypochlorite solutions contain a lot of it.
I measured NaOCl amount via titration with acidified HI, then a free iodine was titrated with Na2S3O3.
Normal reaction is
NaOCl + 2 HI ==> I2 + NaCl + H2O
I can suggest that the solution contained a lot of chlorate. It can give a lot of chlorine by the reaction
NaClO3 + 6 HCl ==> 3 Cl2 + 3 H2O + NaCl
While the reaction with chlorate might go like
NaOCl3 + HI ==> NaIO3 + HCl
without giving a free iodine, and there's a limited amount of iodine in the solution, so maybe the iodate was not able to oxidize hydrogen iodide into iodine, but instead gave off a free chlorine.
There could be a chlorite in the solution, or whatever, I have no other ideas.
Is there any way to measure amount of chlorate in hypochlorite solution?
Maybe I could try to regenerate the hypochlorite, is there any easy way except evaporating the free chlorine and absorbing it with NaOH solution?
UPD: tried to heat the hypochlorite solution to boiling point. I think that color of IPA+hypochlorite solution turned yellow-green after heating - this is the color I've got after heating a pure hypochlorite. And then, when the temperature is approx 90°C, some strange thing started to happen on boiling stones and on the whole surface of liquid-glass contact: smole bubbles are generated, which don't look like a boiling water, but rather some decomposition generating oxygen (chlorate decomposition?). This process generates the precipitate I mentioned above. But this time the solution remains yellow even after reaching the boiling point of water, unlike IPA+NaOCl which turns colorless.
Addition of a small amount of NaOH doesn't change anything.

[Edited on 29-4-2015 by byko3y]