textex
Harmless
Posts: 26
Registered: 29-3-2011
Member Is Offline
Mood: No Mood
|
|
Preparing sodium oxylate
Hello
I hope this one is in the right place.
Anyways, i need some sodium oxylate for a star comp, i saw that you can prepare it from oxalic acid which is pretty easy to get in a 10-15 solution
and NaOH on wikipedia in a 1:2 molar ratio.
I guess that the reaction will go like (CO2H)2 + 2NaOH -> C2Na2O4 + 2H2O that.
Anyways, anyone done it before? Cant find much about it on the net. I guess that the best thing to do would be to make a solution of the NaOH and pour
it in?
|
|
madscientist
|
Thread Moved 29-3-2011 at 13:27 |
Random
International Hazard
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 1018
Registered: 7-5-2010
Location: In ur closet
Member Is Offline
Mood: Energetic
|
|
This is simple neutralisation. Mix oxalic acid and NaOH, you will get sodium oxalate.
Though, I wouldn't recommend you messing with pyro compositions without even knowing basic chemistry. I think you don't even know basic things about
safety and that could lead you to injuries.
[Edited on 29-3-2011 by Random]
|
|
textex
Harmless
Posts: 26
Registered: 29-3-2011
Member Is Offline
Mood: No Mood
|
|
Well, i do know some basic chemistry, and i kind of knew how that reaction would be,but im gonna admit i aint that experienced. But incase i missed up
on anything its always good to have a second opinion other than my own ![;)](./images/smilies/wink.gif)
And judging what i know or dont know on safety on one post....
|
|
Bot0nist
International Hazard
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 1559
Registered: 15-2-2011
Location: Right behind you.
Member Is Offline
Mood: Streching my cotyledons.
|
|
I was into amateur pyrotechnics before I really starting amateur chemistry. Both hobbies are dangerous and both can and have killed. As a young
teenager I made black powder and flash, and as an adult I enjoy making small rockets and various other little projects like aerial shells and flash
pots/fountains. It has been a very fun hobby for me and I have always been able to remain safe by using common sense and learning from the mistakes
others have made in the past.
I think the importance of learning as much as one can from before attempting something dangerous relates to chemistry in a more extreme way than even
pyrotechnics.
That being said, it doesn't sound like what your wanting to do is that dangerous as long as your not oblivious to to basic lab safety.
Also, if you just need it for your star comps and are not really interested in the chemistry of the salt why not buy it. Its like $15-$20 a pound, but
many places won't ship it so you may have a drive.
|
|
Random
International Hazard
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 1018
Registered: 7-5-2010
Location: In ur closet
Member Is Offline
Mood: Energetic
|
|
Quote: Originally posted by textex ![](images/xpblue/lastpost.gif) | Well, i do know some basic chemistry, and i kind of knew how that reaction would be,but im gonna admit i aint that experienced. But incase i missed up
on anything its always good to have a second opinion other than my own ![;)](./images/smilies/wink.gif)
And judging what i know or dont know on safety on one post.... |
Everything is up to you, I just warned you. Though, I am sure it's better to warn someone than giving him information about something dangerous and
not warning him. By the way, use stoichiometry for the best results.
|
|
woelen
Super Administrator
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 7998
Registered: 20-8-2005
Location: Netherlands
Member Is Offline
Mood: interested
|
|
I agree with Random. Home chemistry in general involves some risk and pyrotechnics involves much more risk, due to the inherently energetic reactions
involved.
I would strongly recommend that you try to understand basic chemistry. First you have to learn walking before you can go running.
This reaction you want to do is a nice example of using basic chemistry knowledge. Suppose I start with 100 grams of oxalic acid, how much NaOH is
required to make sodium oxalate? You should be able to answer that question.
In real life things are even more complicated. Do you have anhydrous oxalic acid, or do you have the dihydrate, H2C2O4.2H2O? This is important to
know. If you don't know, then you have to find out yourself by carefully neatralizing a solution of known concentration of the acid with a solution of
known concentration of NaOH and check how much NaOH is needed to concentrate the solution.
Yet another issue you may encounter is that sodium oxalate is only very sparingly soluble. You need to start off with moderately concentrated
solutions of oxalic acid and sodium hydroxide and carefully add the NaOH slowly while stirring. At a certain point Na2C2O4 will separate.
In total you better can have a slight excess of NaOH instead of oxalic acid. Your end product must be absolutely free of acid, otherwise pyrotechnic
mixes with it may become dangerously unstable, especially when combined with chlorates (chlorates and acid is a NO GO in pyrotechnics). Your home made
material also should be allowed to dry very well in contact with air. If a slight excess of NaOH is used, then it will be hygroscopic, but this
property soon disappears if it picks up some CO2 from the air and makes carbonate. Some carbonate in your mix is not bad, it may even help stabilize
your composition somewhat.
As you see, there are many things to think about, even when performing such a simple reaction. For this reason I would say: First think, than act!
|
|
textex
Harmless
Posts: 26
Registered: 29-3-2011
Member Is Offline
Mood: No Mood
|
|
I guess that this would be the calculation for 100g acid:
C2H2O4= 90,03 g/mol
NaOH = 39.99 g/mol
100g / 90,03 = 1,11 * 2 = 2,22 * 39,99 = 88,77 g NaOH
After checking the sources of oxalic acid, the only reasonable price i found is a cleaning agent which contains around 10-15 as stated in the MDS.
Pharmacy had a pretty steep price, and i dunno if i feel like ordering it.
And yeah, im considering using it in a chlorate comp, which i know is pretty unstable, especially S*, acids etc. But its not like im planning to make
anything out of the first batch i make if i do it.
|
|
entropy51
Gone, but not forgotten
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 1612
Registered: 30-5-2009
Member Is Offline
Mood: Fissile
|
|
Quote: Originally posted by textex ![](images/xpblue/lastpost.gif) | After checking the sources of oxalic acid, the only reasonable price i found is a cleaning agent which contains around 10-15 as stated in the MDS.
Pharmacy had a pretty steep price, and i dunno if i feel like ordering it. | Hereabouts the hardware stores
sell wood bleach which is quite good oxalic acid.
|
|