plasma
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Extraction of HCl from solvent
I have a solvent wich contains 12% hydrochloric acid, is there any way to extract the acid or make it stronger ?
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plasma
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Boiling I have tried boiling it until it gets clear or yellowish and it seems like it's getting stronger (tested with sodium hydroxide), but I don't
know how long it should boil.
Thanks again [ ]
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Polverone
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What are the other ingredients in this mixture? HCl has a lower boiling point than water so unless you are removing volatile solvents you will
actually make it weaker. How are you testing it with sodium hydroxide? Adding an indicator to a solution of NaOH and then titrating it with different
acid samples?
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plasma
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I don't know what it contains except 12% HCl. It is a blue colored solution used for cleaning toilets. When boiled fumes appear after a couple of
minutes and the solution turns yellow, the odor of mint also disappears and turns into chlorine odor. When I tested this solution I just simply
dropped a few drops on some sodium hydroxide and saw how vigoursly the reaction was. It was most vigoursly after boiling and released much more
chlorine than it did before boiling. I might have evaporated some hydrochloric acid, but I also evaporated the color and smell compounds.
If this method doesn't work, do you have any suggestions on extracting the acid. Could it be done by distillation.
Thanks
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Polverone
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In the U.S. manufacturers' websites often have an MSDS (material safety data sheet) for their products, which include a detailed listing of the
ingredients. I know you are not in the U.S., but does the manufacturer of your product perhaps have a website with such information? It would be
helpful. But if not, don't despair.
I need to get something very clear: are you smelling chlorine from the toilet bowl cleaner, or are you smelling hydrogen chloride? They both have
sharp, irritating odors, but they are distinct. Something funny is going on if you are getting chlorine just by boiling your cleaner.
When you add your boiled toilet bowl cleaner to sodium hydroxide, is it at the same temperature as your unboiled material? They should be at the same
temperature when you add them to the hydroxide, otherwise the vigor of the reaction will be different even if the acid concentration is identical.
Adding hydrochloric acid to sodium hydroxide should definitely not release chlorine. I'm going to take a guess here: I think that the heat of the
reaction is boiling some hydrogen chloride from your acid and you are smelling that, not chlorine. But if I turn out to be wrong I would be most
intrigued.
Extracting the acid might be possible via distillation but I really don't think you have the equipment to do it safely if you're trying to get acid
from toilet bowl cleaner in the first place. You can make very pure hydrochloric acid by dissolving hydrogen chloride gas in distilled water.
Unfortunately, you would need concentrated sulfuric acid to make the hydrogen chloride gas, and I doubt you would be messing with toilet bowl cleaner
in the first place if you had concentrated sulfuric acid.
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plasma
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Thanks for your reply Polverone.
I agree with you, it couldn't have been chlorine that was released when boiling. I think I will just let the 12% HCl be like it is, it works for
making AP (3x amount).
I found the HCl's msds sheet but not for my toilet cleaner, there was not any data about evaporation or boiling point, so that's the reason for
boiling.
By the way, do you know about any common names or solvents which contains hydrogenperoxide. Mine contains 1-5 %, and that's low, that one is also a
toilet cleaner
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HOOPS123
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| Quote: | | I am telling you fool, sulferic is the way to go if you are making AP, get it from home depot as drain cleaner. it is 98% pure.
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There is no reason to call him a fool for asking a question. Yes, I think sulfuric acid is easier to come by, but it is his choice not yours
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madscientist
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I have heard that it is very difficult to find sulfuric acid in some countries other than the United States and the Netherlands.
I weep at the sight of flaming acetic anhydride.
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plasma
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Does Sulfuric acid give higher yields than Hydrochloric acid ?
The only sulfuric acid I can get is from car batteries, I don't think they sell it (or any other usefull chemical) without a license here in Norway.
Thanks for the support HOOPS123 and madscientist
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PHILOU Zrealone
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Below the 33% HCl is a stronger acid than H2SO4! But being a very volatile one, is a disavantage when it comes in contact with 98% H2SO4.
HCl(33%) 1 vol + 1 vol H2SO4 (98%) will result in a HCl evacuation due to the fact H2SO4 takes the water to solvate itself, produces heat and HCl
leaves the system as a gas!
Solubility of gases decreases with every T increases (reason why river/lake fishes are happy when it is 5°C and unhappy when it is 40°C; O2
concentration drop by a lot when water is hotter!).
A good way to get gasfree water is to boil it; therefore, boiling HCl will result in a weaker acid as mentioned Polverone.
HCl can be prepared easily as a gas when H2SO4 conc is boiled with NaCl; (this should work for H2SO4 of minimum 40%); lab preparation uses H2SO4 98%
on dry NaCl
H2SO4 + NaCl --> NaHSO4 + HCl
Acidity constant of HCl is 10^6
HCl -H2O-> H(+) + Cl(-)
Ka= 10^6= (concH(+))*(concCl(-))/(concHCl)
this means that you have 1/10^6 molecule of HCl that remains undissociated as H(+) and Cl(-) at the equilibrium.
For H2SO4
H2SO4 -H2O-> H(+) + HSO4(-)
Ka1= 10^4 this acid is thus 10^6/10^4=100 times less dissociated and thus 100 times less acid than HCl!
HSO4(-) -H2O-> H(+) + SO4(2-)
Ka2= 1,25*10-2 this acid is thus 10^4/(1,25*10^-2)= 800 000 times less acid than H2SO4 first proton. Subsequently, you undeerstand that
hydrogenosulfate acid is 80 000 000 times less acidic than HCl!
Now speaking of CTAP, it is catalysed by acids; if H2SO4 is used too concentrated, it heats the batch and you end up with more CDAP than CTAP. Diluted
H2SO4 being less acidic than HCl will be a poor catalyst.
1% HCl is equal as catalyst to the acidity power of 100% H2SO4!
12% is more than sufficient and prevents excessive heat due to the 88% water that cools down the batch --> CTAP is major product!
I used 33% HCl (maximum % reachable at STP) to make CTAP; and it heats a little and works fine all my aceton was converted to cristalline CTAP in less
than a night outside (5°C).
PH Z
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plasma
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Thanks for that very informative reply PH Z.
What do you think about this ratios for making CTAP.
50% HCl(12%)
30% H2O2(5%)
20% Acetone
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PHILOU Zrealone
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50% HCl(12%)
30% H2O2(5%)
20% Acetone(100%)
I would say no way!
It should be more like:
5-10% HCl (12%)
80-85% H2O2 (5%)
10% CH3-CO-CH3 (100%)
*Catalyst only enter the reaction as minor ingredients (you put it as a major ingredient).
*You also have an exces of aceton that will prevent good cristallisation due to solvatation of the low yield CTAP
*Too little H2O2 will lead to low yield!
PH Z
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plasma
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I tried your amounts whitout luck. It has been standing for two days in the fridge (T = 4 C) and no cristalls have appeared.
Adding some 30% HCl helped alot though.
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Hoffmann-LaRoche
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sulfuric/hydrochloric acid replacement
For AP synth, also NaHSO4(drain cleaners) and also my cheap favourite, NH4HSO4 will probably work.
Where i live, making NH4HSO4 from (NH4)2SO4 by heating, it is as 5-10 times cheaper as a source for strong H+.
The HSO4- ion acts as a strong acid, like HCl at the same concentration.
greetings, HLR
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PHILOU Zrealone
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I really think you should read again the concepts of pKa's and acid dissociation equilibrium constants (Ka's).
Or try to undertand what I have written before!
HCl is 100 times more acid than H2SO4 first deprotonation that is itself 800 000 times more acid than HSO4(-) !
So live with that:
HCl>H2SO4>>>>HSO4(-) on the acidity scale!
PH Z
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mick
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HCl
I thought that there is a constant boiling HCl.
If you boil water saturated with HCl, HCl comes of first, then HCl/water, then water.
I think the constant boiling mixture is about 25-30%. I think the boiling point is about 103.
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