Elite Engineer Posted October 26, 2013 Share Posted October 26, 2013 I'm trying to synthesize peracetic acid (via hydrogen perxoide + acetic acid), but want know more knowledge of its boiling point for safety reasons. Two different, reliable sources tell me two very different results of its boiling point. One source says it's 25 degrees celsius, while the other says its 119 degrees celsius +/- 23 degrees. my question is: Which boiling point is the correct one, and is it sill safe to synthesize it, and would you still synthesize if you were unsure? thx, ~ee here are the sites: claims bp = 25 degrees C: http://onlinelibrary.wiley.com/doi/10.1002/047084289X.rp034.pub3/abstract claims bp = 119 degrres C +/- 23 degrees http://www.chemspider.com/Chemical-Structure.6336.html?rid=ae43221f-23e1-4a76-8720-08dd2ee342ca Link to comment Share on other sites More sharing options...
John Cuthber Posted October 26, 2013 Share Posted October 26, 2013 The first source says "Physical Data: mp 0 °C; bp 25 °C/12 mmHg; d 1.038 g cm−3 at 20 °C." The 25 °C/12 mmHg; means that the stuff boils at 25C under a pressure of 12 mmHg. If you don't understand that sort of thing you probably shouldn't be working with explosive- far less planning to boil them. What are you hoping to achieve? Link to comment Share on other sites More sharing options...
Elite Engineer Posted October 26, 2013 Author Share Posted October 26, 2013 (edited) What are you hoping to achieve? I'm trying to observe the disinfectant properties of peracetic acid in water, as an alternative to chlorine disinfectant. However, I noticed that the second source (chemspider) says it boils at 119 degrees C +/- 23 degrees under 760 mmHg. I'm aware of the products high toxcitiy and unstability at moderately high temperatures, so I'm only using a very small amount. Boiling Point: 119.1±23.0 °C at 760 mmHg (via chemspider) -question still unanswered Edited October 26, 2013 by Elite Engineer Link to comment Share on other sites More sharing options...
John Cuthber Posted October 26, 2013 Share Posted October 26, 2013 Why do you want to know the boiling point? It's likely to explode if you boil it. Link to comment Share on other sites More sharing options...
Elite Engineer Posted October 26, 2013 Author Share Posted October 26, 2013 Why do you want to know the boiling point? It's likely to explode if you boil it. No, I just want to know if it's safe to synthesize at room temperature or not. I dont want to make it, and then have it's vapors burn my lungs. Link to comment Share on other sites More sharing options...
John Cuthber Posted October 26, 2013 Share Posted October 26, 2013 Well, you now know that, at near room temperature, it has a vapour pressure of a little under 12 mmHg. Link to comment Share on other sites More sharing options...
crytalline silver Posted November 17, 2013 Share Posted November 17, 2013 heard of colloidal silver used as disinfectant silver supposta kill up to 600 pathogens virsues and bateria just a thought crytalline Link to comment Share on other sites More sharing options...
Elite Engineer Posted November 17, 2013 Author Share Posted November 17, 2013 heard of colloidal silver used as disinfectant silver supposta kill up to 600 pathogens virsues and bateria just a thought crytalline yes, I've heard of that as well, but I'm trying to synthesize a strong oxidizer from household chemicals (yes I know about bleach, w.e). However, I did synthesize it with a weak concentration of acetic acid (vinegar) and concentrated hydrogen perxoide. I tested the pH, and it was surpisingly acidic (about 3.5) . I experienced no breathing issues, and carried out the reaction outside (about 25 degrees F). About to make a more potent soltuon and test it on a bacterial sample. Link to comment Share on other sites More sharing options...
John Cuthber Posted November 17, 2013 Share Posted November 17, 2013 You do know that hydrogen peroxide and vinegar will both kill bacteria anyway, don't you? Link to comment Share on other sites More sharing options...
Elite Engineer Posted November 18, 2013 Author Share Posted November 18, 2013 You do know that hydrogen peroxide and vinegar will both kill bacteria anyway, don't you? yes, but neither of them are very strong acids. Link to comment Share on other sites More sharing options...
hypervalent_iodine Posted November 18, 2013 Share Posted November 18, 2013 yes, but neither of them are very strong acids. Why does that matter? Surely if the point is simply to kill bacteria and both the peroxide and the acetic acid already do this, making something that poses a greater safety risk for the same purpose is a bit beyond redundant? Link to comment Share on other sites More sharing options...
John Cuthber Posted November 18, 2013 Share Posted November 18, 2013 yes, but neither of them are very strong acids. Nor is peracetic acid. Did you check the pH of the vinegar and the peroxide before you mixed them? Hydrogen peroxide solutions are often acidified because they are more stable in acid conditions. pH 3.5 isn't very acid for vinegar. Link to comment Share on other sites More sharing options...
Elite Engineer Posted November 20, 2013 Author Share Posted November 20, 2013 Nor is peracetic acid. Did you check the pH of the vinegar and the peroxide before you mixed them? Hydrogen peroxide solutions are often acidified because they are more stable in acid conditions. pH 3.5 isn't very acid for vinegar. When I made the peracetic acid, I tested it with a pH indicator strip. Comparing the results to the different pH levels, this was a minimum of 3.5, maybe less than 3, or even 2.9, 2.8. Maybe I added too much acetic acid or w.e. Why does that matter? Surely if the point is simply to kill bacteria and both the peroxide and the acetic acid already do this, making something that poses a greater safety risk for the same purpose is a bit beyond redundant? there's always epoxidation I guess. I've read some literature stating that peracetic acid is a strong oxidizer than hydrogen peroxide. Link to comment Share on other sites More sharing options...
John Cuthber Posted November 20, 2013 Share Posted November 20, 2013 Peracetic acid is a stronger oxidant than hydrogen peroxide. At the moment, your "evidence" for peracid formation is a pH measurement that won't tell you anything, made with coloured paper. Hydrogen peroxide will destroy some dyes used in that paper. You need to think this through better Link to comment Share on other sites More sharing options...
Elite Engineer Posted November 20, 2013 Author Share Posted November 20, 2013 Peracetic acid is a stronger oxidant than hydrogen peroxide. At the moment, your "evidence" for peracid formation is a pH measurement that won't tell you anything, made with coloured paper. Hydrogen peroxide will destroy some dyes used in that paper. You need to think this through better I did find some sources that say hydrogen peroxide is a slightly stronger oxidizer than PAA. Looking back, I did use excess hydrogen peroxide in my synthesis. I'm going to use concentrated acetic acid this time and mix in the correct proportions..I'll find a different pH measuring method and report back to you. Link to comment Share on other sites More sharing options...
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