Sciencemadness Discussion Board

Synthesis of Phosphorus Pentoxide

100PercentChemistry - 12-9-2015 at 12:14

I know it can be made with Phosphorus, but that is hard to get. Are there any good methods you know of? Can I make it with Phosphoric Acid?

aga - 12-9-2015 at 13:30

Strange desperate tone to your post 100PercentChemistry.

Do you really need it for something ?

100PercentChemistry - 12-9-2015 at 14:03

I am using it to dehydrate. https://m.youtube.com/watch?v=i8WGGnfXII8. Is this banned, I wasn't aware of anything like that. I asked him if I could use anything else and he said not that I i know of. Sorry if I sounded desparate. The acetonatrile can be used as a solvent. My main use is to synthesize other chemicals from that. It is expensive to buy where I found. I can also use that to make acetyl chloride, and use that to make acetic anhydride which is useful also. Do you knew another chemical that would work?

[Edited on 12-9-2015 by 100PercentChemistry]

[Edited on 12-9-2015 by 100PercentChemistry]

aga - 12-9-2015 at 14:13

You just want to burn paper ( i watched the video ) ?

100PercentChemistry - 12-9-2015 at 14:20

https://m.youtube.com/watch?v=i8WGGnfXII8 to https://m.youtube.com/watch?v=Q2ArDw0vf2Q to https://m.youtube.com/watch?v=MSXrEUcTNi8 I have some ideas for the acetic annydride. I also want to use it to synthesize acetanalide so I can try out the p nitroanaline reaction myself. Again is there any more commonly available chemical I could use to dehydrate instead of Phosphorus pentoxide???

[Edited on 12-9-2015 by 100PercentChemistry]

aga - 12-9-2015 at 14:29

Do i have to watch all the videos ?

Edit:

Better to just ask questions about your Ideas than post links to a load of videos.

[Edited on 12-9-2015 by aga]

gdflp - 12-9-2015 at 15:28

Quote: Originally posted by 100PercentChemistry  
I am using it to dehydrate. https://m.youtube.com/watch?v=i8WGGnfXII8. Is this banned, I wasn't aware of anything like that. I asked him if I could use anything else and he said not that I i know of. Sorry if I sounded desparate. The acetonatrile can be used as a solvent. My main use is to synthesize other chemicals from that. It is expensive to buy where I found. I can also use that to make acetyl chloride, and use that to make acetic anhydride which is useful also. Do you knew another chemical that would work?

No aga, it is not a dehydrogenation, it is a dehydration; and a very difficult one at that. Phosphorus pentoxide is the only compound that I know of that will work, and it cannot be synthesized from phosphoric acid without elemental phosphorus being an intermediate, that adds all sorts of elements of complexity. If you're in the US, a cheap source of P2O<sub>5</sub> is from Firefox F/X, it will be cheaper than making it yourself from phosphoric acid.

In addition, synthesizing acetamide, then from that going to acetonitrile, acetyl chloride, and finally acetic anhydride is far too much work for a relatively simple compound and is a waste of time and money. See the "acetic anhydride preparation" thread and Magpie's thread in Prepublication for syntheses of acetic anhydride from anhydrous sodium acetate and S<sub>2</sub>Br<sub>2</sub>/S<sub>2</sub>Cl<sub>2</sub>. <i>Hint, acetic anhydride is not necessary to acetylate aniline</i>

Sulaiman - 13-9-2015 at 01:56

If it is just that you want acetic anhydride
I bought it here http://onyxmet.com/?route=product/product&filter_name=ac...
quick, easy, cheap.

aga - 13-9-2015 at 02:56

Quote: Originally posted by gdflp  

No aga, it is not a dehydrogenation, it is a dehydration

Really ? Ah crap.

Even the words in OC are difficult.

I'll delete that post seeing as it's utterly wrong.

byko3y - 13-9-2015 at 06:12

Phosphoric acid can be dehydrated to P2O5, you need something like 500°C, but the problem is that there are only few materials which can hold the hot HPO3-P2O5. The only one material I know is graphite. Glass will melt really fast, most metals will corrode quickly, something like platinum or gold can be used. So what you need is a platinum reactor with platinum tubes leading into receiver for P2O5 vapors. Pretty easy and straightforward method, as you can see.

Bert - 13-9-2015 at 07:19

Try a google search on your terms of interest + sciencemadness.org, there are a TON of existing threads on both Phosphorus compounds and acetic anhydride production.

And read the FAQ. http://www.sciencemadness.org/madscifaq.html#2.1_Board_topic...

Also try plainly stating what your ends are, with references and/or description of any work you have performed. Then you can do it outside of beginnings!

I deleted your double post.