Sciencemadness Discussion Board - Scared of ClO2

Scared of ClO2

plante1999 - 4-11-2011 at 16:13

Today I tried to disolve Ni by mixing a KClO3 Sol. and 98% H2SO4. At start it was making a small amount of ClO2 so I did not care. I attempted to change the beaker of place (I was outside) but it literaly exploded with a loud sound. I was scared as hell!!! (I never saw energetic material) But I was wearing my heavy nitril glove and my goggles, my pyrex classic beaker did not survive and glass shard did not cut my glove or me....

I am absolutly not harmed.

Please be carefull with ClO2

Thanks!!!

[Edited on 5-11-2011 by plante1999]

[Edited on 5-11-2011 by plante1999]

BromicAcid - 4-11-2011 at 18:18

I had the same thing happen once when I thought it was a good idea to dissolve match heads in HCl.

Chemistry Alchemist - 4-11-2011 at 20:57

Isnt it produced a bit by reacting bleach with HCl? OMG i done that (dissolve match heads in HCl) it started to smell a but but didn't react any explosion from ClO2 :O that was a yr ago tho... i know better not to do that

madscientist - 4-11-2011 at 22:49

Chemistry Alchemist: that just produces Cl2... no ClO2.

Chemistry Alchemist - 4-11-2011 at 22:59

Thanks

i thought i read somwhere about easly producing it with bleach.... i guess i just mistaken it for Sodium Chlorite
5 NaClO2 + 4 HCl = 5 NaCl + 4 ClO2 + 2 H2O

blogfast25 - 5-11-2011 at 03:45

Quote: Originally posted by plante1999

Today I tried to disolve Ni by mixing a KClO3 Sol. and 98% H2SO4. At start it was making a small amount of ClO2 so I did not care. I attempted to change the beaker of place (I was outside) but it literaly exploded with a loud sound. I was scared as hell!!!

Did you realise before you started that you were inadvertently creating a potentially very explosive chemical compound?

Clearly you were trying to create your own version of 'a poor man's aqua regis' , but with substitutes.

For Ni, HNO3 is the recommended solvent. Try to find 'pH Down' solutions from the marihuana people: in liberal Canada you must be able to buy 35 % HNO3 (if not actually straight from eBay). Concocting unpredictable mixtures like the one you tried is not wise; an accident would have resulted sooner or later, FSM bless that this one was without real consequences!

Anyroads, glad you're in one piece...

[Edited on 5-11-2011 by blogfast25]

plante1999 - 5-11-2011 at 04:45

Quote: Originally posted by blogfast25

I calculed my ratio of H2O , KClO3 and H2SO4 to make about 40% HClO3 (which is suposed to be stable, I already make 35% and it was stable) but it seem that this conssentration was too unstable , and release ClO2.

I was trying a more conssentred ''poor man'' nitric acid. I have already make 35% HClO3 and it was disolving metal like HNO3 but I was thinking that it was too dilute.

Chemistry Alchemist - 5-11-2011 at 04:48

Would there be a way to stop ot from exploding if it forms? Or will it explode in any environment it's produced in?

plante1999 - 5-11-2011 at 04:59

Not realy , but you can make sodium chlorite which is more stable.

Lets see the nfpa 704 for ClO2 , wich scare me alot.

woelen - 5-11-2011 at 05:30

HClO3 only is stable without reductors. When a reductor is immersed in such a solution, then the chloric acid is reduced to chloride, which in turn can react to ClO2 with excess chloric acid. Just for demonstration, put a spatula of KClO3 in a few ml of 30 percent sulphuric acid and then add some table salt. Immediately the liquid turns bright yellow, due to formation of ClO2.

Bot0nist - 5-11-2011 at 05:38

Chloric acid makes some fun demos. Most everybody is familiar with its instant and violent reactions with organics or any fuels really

http://www.youtube.com/watch?v=MaLK6MMkOpQ&feature=playe...

Chemistry Alchemist - 5-11-2011 at 05:48

I think on wiki it said sodium chlorite can be made by passing chlorine dioxide through a alkaline base (sodium hydroxide) and then reduced to with hydrogen peroxide to form sodium chlorite... Correct me if Wong

how can u safely pass chlorine dioxide through sodium hydroxide with out blowing up your glassware each time chlorine dioxide is made?

Endimion17 - 5-11-2011 at 05:51

You can safely observe a test tube full of gas if it's squeaky clean and you don't try to do anything mad with it. Many stories of "horrific, violent compounds" are myths made up when people were working in dirty glassware with impure chemicals, and trying to "tease" the chemical.

Chlorine dioxide in such small amount, in a stable, nonreductive sorroundings is safe.

Chemistry Alchemist - 5-11-2011 at 06:07

So would there be another practical way to make sodium chlorite?

Neil - 5-11-2011 at 06:25

Quote: Originally posted by blogfast25

For Ni, HNO3 is the recommended solvent. Try to find 'pH Down' solutions from the marihuana people: in liberal Canada you must be able to buy 35 % HNO3 (if not actually straight from eBay). Concocting unpredictable mixtures like the one you tried is not wise; an accident would have resulted sooner or later, FSM bless that this one was without real consequences!

Nope not even 15% hydro shops only sell 12% now because of the 2008 restrictions. They want 30$ for 400ml...

Glad you are okay Plant, sorry to hear about your beaker.

blogfast25 - 5-11-2011 at 06:51

Quote: Originally posted by Endimion17

You can safely observe a test tube full of gas if it's squeaky clean and you don't try to do anything mad with it. Many stories of "horrific, violent compounds" are myths made up when people were working in dirty glassware with impure chemicals, and trying to "tease" the chemical.

Chlorine dioxide in such small amount, in a stable, nonreductive sorroundings is safe.

C'mon, Endi: ClO2 has inherently a low (maybe even positive?) heat of formation, that makes it quite unstable.

strontiumred - 5-11-2011 at 08:03

The only serious incident I had was probably the result of chlorine dioxide. I was trying to make the interhalogen compound KICl4. I stupidly capped the tube before heating a mixture of potassium iodate and conc. HCl. Took the tube out of the hot water, swirled it and bang! Glass and acid everywhere.

Even more stupidly I was not even wearing goggles. I got lucky, I used up a life that day and am now very careful. Goggles go on BEFORE I do anything!

woelen - 5-11-2011 at 08:05

ClO2 is never safe. Even in clean glassware it can explode, e.g. by bright light. Even diffuse daylight may provoke an explosion. I made the gas many times, see my website, and indeed I have had small explosions a few times. I only make test tube quantities and do not onfine the gas, and then a small explosion does no harm.

strontiumred - 5-11-2011 at 08:22

It's all about understanding the risk. If I had read up on the compound first I would probably have been OK. Even though it was only a minor side product of the reaction when the concentration reached a certain point it become unstable! I went back and did it again in an open tube and all was fine - Did the rubidium version too (thanks woelen) and that was fine too. Lovely square crystals!

plante1999 - 5-11-2011 at 12:54

Does BrO2 is instable like ClO2 or it is more stable?

Hop it is clear: do NOT use ClO2 for making a compound and check if there is a probability that ClO2 was made during an experiment. So Chemistry Alchemist do not attempt a synthesis with it.

Note: It seam that heavy nitril glove shield efficienly glass shard....

Shotgun Man - 14-11-2012 at 10:06

ClO2, according to wikipedia, will readily decompose in an explosive manner above partial pressures of 10,000 Pa, or 30% v/v. While this is true, I have concluded that ClO2 will still "pop" at concentrations of 10%v/v.

Therefore, it seems reasonable to assume that introducing a method to exhaust ClO2 and introduce atmospheric air at an appropriate rate for your set-up/quantities would alleviate the risks when dealing with ClO2 as a by-product. Provided you do not need a vacuum, this should work well even in a distillation set up.

I suspect the beaker exploded not by ClO2, but by the formation of large amounts of HClO3. Apparently it is stable when chilled at low concentrations, however at standard temperatures it may be a different story. I have heard of chloric acid solutions at room temperature loosing their shit and turning storage vessels into grenades. A quick search on wikipedia seems to verify that combining KClO3 with H2SO4 forms an unstable mixture.

AJKOER - 14-11-2012 at 11:25

Quote: Originally posted by Chemistry Alchemist

So would there be another practical way to make sodium chlorite?

Here is one route, Per Mellor, page 289, http://books.google.com/books?id=AnnVAAAAMAAJ&pg=PA289&a... to quote:

"Iodine separates from an acidified soln. of potassium iodide: 2Cl02+10HI=2HCl+4H20+5I2; in neutral soln.: 6Cl02+10KI=4KI03 +6KCl+3I2; and in the bicarbonate soln.: 2Cl02+2KI=2KCl02+I2, whereby 80 per cent, of the chlorine dioxide is converted into the chlorite."

So treat a bicarbonate solution of Potassium iodide with ClO2. Should have a good yield of Chlorite.

You can collect the Iodine and recycle to make an iodide (dissolve in NaOH or KOH to form an Iodide and some Iodate):

3 I2 + 6 NaOH = 5 NaI + NaIO3 + 3 H2O

feacetech - 14-11-2012 at 12:54

Quote: Originally posted by madscientist

Chemistry Alchemist: that just produces Cl2... no ClO2.

When i was working in water treatment a collegue in another country had the unfortunate accident of mixing HCl and hypo

its safe to safe his chemistry was as poor as his attention to detail & the result was he lost 80% of his lung function (didnt understand what the strange coloured fumes emiting form his tank of hypo were)

On a side note ClO2 was used during the USA anthrax scare to kill the spores, it was disspersed via modified colling towers (inside buildings)

A collegue told me they had to convince them they would not blow up the building and he said that there is very good and accurate data around pressure, temperature and conc of ClO2 for explosive thresholds, and that it is very predicable I havnt seen this data but if someone dug it up it would be usefull

AJKOER - 16-11-2012 at 14:10

Quote: Originally posted by AJKOER

You can collect the Iodine and recycle to make an iodide (dissolve in NaOH or KOH to form an Iodide and some Iodate):

3 I2 + 6 NaOH = 5 NaI + NaIO3 + 3 H2O

Alternately, per this net ionic equation (see http://www.sciencebuddies.org/science-fair-projects/project_... ):

C2O4- + I2 → 2 I- + 2 CO2

one could use an Oxalate or Oxalic acid to recycle all the Iodine back to Iodide.

Random - 17-11-2012 at 04:23

That was just looking for explosion man. You actually didn't create bleach but heavy metal perchlorate (or chlorate). Not sure which one but I have read that special care needs to be taken to not produce any metal percholrates while handling the said acid.

Stay safe

Eddygp - 17-11-2012 at 07:03

Safety above all.

[Edited on 17-11-2012 by Eddygp]