Sciencemadness Discussion Board

H2O2 question

Camroc37 - 7-8-2015 at 08:37

I don't use my home-concentrated H2O2 often, but when I took it out today I noticed a white powder that has settled on the bottom. What is this?

MrHomeScientist - 7-8-2015 at 09:29

There's no way anyone can answer such a vague question. We need more information than that. How did you concentrate it? What was your initial source of the peroxide? How long has it been in storage? My first thought is some impurity in the original stock, or a remnant of whatever process you used to concentrate it, but without knowing more we can't be sure. Why not run some tests on it?

szuko03 - 7-8-2015 at 10:09

I would be careful with peroxide and random powders it may form they tend to be sensitive explosives. I doubt thats what this is but I just wanted to toss that out there. But as MHS said without anymore info who knows what it could be.

aga - 7-8-2015 at 11:20

It is The Powder of Most Splendid Whiteness, the like of which has never before been seen, yet was foretold it's coming in the darkest ancient pages of the books of divine knowingness.

Alternatively, just filter it out and have a look at it.

Brom - 7-8-2015 at 18:41

If anyone ever needs 50% h2o2 I can get it by the gallon. I am looking into starting a chemical supply business considering the distributors that I have relationships with. I also can get bulk explosive (or tech) grade AN and many other hard to find chemicals

Brom - 7-8-2015 at 18:44

I hope this was not the wrong thread to post this. If so I apologize to the science madness community.

Camroc37 - 7-8-2015 at 19:17

I boiled off the water. It was initially 3% hydrogen peroxide. I'm hardly a professor so I don't know what "tests" I can run on it.

kecskesajt - 7-8-2015 at 23:44

My theory:
Common drug-store H2O2 is stabilised with K/Na phosphates.Due to its solubility,I think it wont precipitate.But you could had other Ca or Mg ions in your glassware wich is makes insoluble alkaline earth phosphates.Its quite possible because I saw your video about Ca metal + water reaction.

battoussai114 - 8-8-2015 at 05:17

Quote: Originally posted by Camroc37  
I boiled off the water. It was initially 3% hydrogen peroxide. I'm hardly a professor so I don't know what "tests" I can run on it.

Usually when working with compounds that came from peroxides there isn't much testing I'd be willing to do, you never know if the mystery material is energetic or not and I wouldn't do chemical testing because of it. So unless I could get a UV-Vis or Raman Spectra I'd just filter it and get rid of it.

DeepBluePotato - 8-8-2015 at 06:50

Quote:
Quote:
A) I had no idea you could actually concentrate H202 using home technology. It was my understanding that it's too unstable to remain in solution after reaching distillation temperatures.

[quote=MrHomeScientist]There's no way anyone can answer such a vague question. We need more information than that. How did you concentrate it? What was your initial source of the peroxide? [etc]


B) If we assume a certain level of sophistication, namely that they cannot themselves understand the possible outcomes of H202 storage, we can assume their behavior pattern by extrapolating from an average person's level of understanding.

C) [quote=kecskesajt]My theory:
Common drug-store H2O2 is stabilised with K/Na phosphates.Due to its solubility,I think it wont precipitate.But you could had other Ca or Mg ions in your glassware wich is makes insoluble alkaline earth phosphates.Its quite possible because I saw your video about Ca metal + water reaction.

Camroc37 - 8-8-2015 at 16:49

The boston round bottle it is in has never been used for anything else. I used a beaker to boil it. I have seen this powder in other places online, and on some videos people have even mentioned this powder as "a sign you used concentrated H2O2". I guess I can filter it, separate it carefully, and burn about a tenth of a gram to see what happens.

The Chemistry Shack - 9-8-2015 at 04:49

Quote: Originally posted by Camroc37  
The boston round bottle it is in has never been used for anything else. I used a beaker to boil it. I have seen this powder in other places online, and on some videos people have even mentioned this powder as "a sign you used concentrated H2O2". I guess I can filter it, separate it carefully, and burn about a tenth of a gram to see what happens.


Not that this will answer your question, but did you boil down the solution or heat-evaporate it at around 80 to 90 C? Because boiling hydrogen peroxide tends to decompose all of it, so if you boiled than you probably have water at this point. I think the phosphate option would make the most sense, except more information is needed to answer it. If the bottle has been in storage for a while with no precipitate, then unless a large amount of the solution was allwoed to evaporate, I don't see why any phosphates would precipitate, as their solubility remains constant. Perhaps it was a temp issue? Was the solution/weather colder than normal when you observed the precipitate?

Bot0nist - 9-8-2015 at 10:54

The members telling you that it is a fools errand to "boil" a hydrogen peroxide solution in order to concentrate it are correct. Unless you are boiling out the diluting fraction of water at much lower temeratures by utilizing reduced pressures with proper glassware and a vacuum pump. Heating a solution of H<sub>2</sub>O<sub>2</sub> until it starts to boil under standard pressure will reach temeratures that will rapidly decompose the H<sub>2</sub>O<sub>2</sub> in the solution as it boils, likely leaving you with nothing more than water.

Upon searching this forum you will find several threads about concentrating the common and very dilute OTC hydrogen peroxide solutions to various and more useful strengths. Many of these threads contain methods that can be used to great success, and are well within the abilities of even the most novice and unequiped hobbiests. Several members here have, over the years, posted workable and effective methods, and even detailed and reproducible experimentals on this subject as well as ways to determine, at least roughly, what concentration was achieved. M1tanker, myself, and several others have posted first hand experiances and conclusions in the past. They are available to any and all intrested to take advantage of. Just a mere search away.

Please, UTFSE, search multiple related terms and phrases, and you will be provided with all the information, procedures, and even step by step "recipes" for the concentration of dilute H<sub>2 </sub>O<sub>2</sub> solutions that one could ever need.

I wish you luck, and fortuitous searching. Knowledge is power, and in this age of easily and freely available information, ignorance is a choice.

[Edited on 9-8-2015 by Bot0nist]

ave369 - 12-8-2015 at 00:29

In my country, we have vacuum canning sets, which consist of lids for common glass jars with nipples, and pumps that draw air from jars through those nipples. A good vacuum canning set provides a nice way to concentrate H2O2. You just pour the dilute solution in a common pickle jar, seal it with the vacuum lid and start working with the pump, while gently heating the jar at the same time. Soon, water starts to boil at the reduced pressure. Keep working with the pump to extract water vapor from the jar. Keep pumping until a desired concentration of H2O2 is achieved.

j_sum1 - 12-8-2015 at 00:38

Sounds interesting. How efficient is this? How much H2O2 decomposes? Any reason why this couldn't be done with a vacuum pump and flask?

ave369 - 12-8-2015 at 10:58

It's the same as vacuum pump and flask. But pickle jars and vacuum canning sets are much easier to come by in rural Russia. I have to take a train to Moscow, or risk ordering by Mail of Russia (which is notorious for breaking glassware en route) to get a Bunsen flask. And pickle jars and vacuum canning sets, this I can buy at the town store.

As for the losses, it's hard to tell. Because the peroxide I can buy at the town drugstore can have anything from 2% to 5% (or none at all, if it's expired). So the yield is unpredictable. I know when to stop, when the peroxide starts to oxidize my fingertip white. However, I can easily end up with no peroxide at all.



[Edited on 13-8-2015 by ave369]

DeepBluePotato - 14-8-2015 at 09:01

Quote: Originally posted by ave369  
In my country, we have vacuum canning sets, which consist of lids for common glass jars with nipples, and pumps that draw air from jars through those nipples. A good vacuum canning set provides a nice way to concentrate H2O2. You just pour the dilute solution in a common pickle jar, seal it with the vacuum lid and start working with the pump, while gently heating the jar at the same time. Soon, water starts to boil at the reduced pressure. Keep working with the pump to extract water vapor from the jar. Keep pumping until a desired concentration of H2O2 is achieved.


Fascinating! Can you get a picture of this technology? Preferably on a breast, since I assume the technology would be similar and it'd make sense to vac-seal that too, since breastmilk is unpasteurized.

[Edited on 14-8-2015 by DeepBluePotato]

chemrox - 14-8-2015 at 17:31

how's he supposed to check the concentration? bp? could he distill it with a water pump?

the white powder could be a metal cation precipitated by peroxycarbonic acid (?) Na+ or Ca++. The manufacturer probably used local water not thoroughly distilled. See http://www.tappsa.co.za/archive3/Journal_papers/decompositio...

[Edited on 15-8-2015 by chemrox]

ave369 - 15-8-2015 at 01:10

Quote: Originally posted by DeepBluePotato  

Fascinating! Can you get a picture of this technology? Preferably on a breast, since I assume the technology would be similar and it'd make sense to vac-seal that too, since breastmilk is unpasteurized.

[Edited on 14-8-2015 by DeepBluePotato]


Sorry, I don't quite understand you. What do you mean by "breast" and how it relates to hydrogen peroxide?


Oh, I've just realized: you are poking fun at the word "nipple". For your information: I was referring to pressure nipples. As in, devices that let the air go one way and don't let it go the other way. And not the kind you imagined, you dirty Western profligate. The State Television was right when they said you are all perverts! And I thought it was just propaganda...



[Edited on 15-8-2015 by ave369]

Bot0nist - 15-8-2015 at 15:37

It was a lame joke, but you shouldn't generalize. I don't assume your tanked on vodka.

[Edited on 15-8-2015 by Bot0nist]

ave369 - 15-8-2015 at 23:07

I just countered a lame joke with an equally lame one.