Nitrous2000
Hazard to Self
Posts: 59
Registered: 1-11-2013
Member Is Offline
Mood: No Mood
|
|
perfluoro sulphonic acid synthesis?
Hey Folks,
Anyone have any experience with making/obtaining this compound? I have seen some posts around Nafion, and commenting on cost. But nothing around
substitutes....
Has anyone looked at the use of ion-exchange resins as a substitute? There are fluoro sulfonate based resins, but they are 1) very expensive and 2)
difficult to obtain.
Any suggestions that don't start with perfluorsulfonic acid would be appreciated 
Thanks
Doug
|
|
|
njl
National Hazard
Posts: 609
Registered: 26-11-2019
Location: under the sycamore tree
Member Is Offline
Mood: ambivalent
|
|
Some perfluorosulphonic acids are used commercially as surfactants, and that's really all I (and I think most people here) can add. It would be a very
very bad idea to try to fluorinate something like this at home. What do you mean "use of ion-exchange resins as a substitute"? Substitute in what
context?
Reflux condenser?? I barely know her!
|
|
|
clearly_not_atara
International Hazard
Posts: 2799
Registered: 3-11-2013
Member Is Offline
Mood: Big
|
|
This is basically impossible. I'm sure you knew that, but anyway, let's talk about the direct cupration of fluoroform!
https://pubs.acs.org/doi/10.1021/ja2081026
Reacting the fluoroform cuprate with S2Cl2 should give perfluorodimethyl disulfide. Oxidation with hydrogen peroxide gives triflic acid. This is
adapted from the Wikipedia synthesis of triflic acid.
Disadvantages: you need tBuOK or a replacement, not sure if other alkoxides work; you probably need non-alcoholic solvents, none of this Na in EtOH
bullshit; you need to make S2Cl2; I don't have any idea what the properties of (CF3)2S2 are; we haven't even talked about how to make fluoroform
So anyway, since I picked fluoroform as a starting point, you're probably wondering, gee, how do I make fluoroform? Well, you have a couple of options
and they all suck. You can try to make it from various refrigerants; you can decarboxylate trifluoroacetic acid, if you can buy that; you can react
bromoform with various metal fluorides below -15 C; you can react formic acid with sulfur tetrafluoride. Of these the bromoform method is the original
and most practical.
In all of that time, you could probably have figured out how to steal some... 
|
|
|
Dr.Bob
International Hazard
Posts: 2751
Registered: 26-1-2011
Location: USA - NC
Member Is Offline
Mood: No Mood
|
|
Are you looking for grams or pounds of it? You can get lower MW ones still, like perfluorobutyl which is the replacement for the perfluorooctyl acid
and sullfonic acid. But the longer chain ones are almost completely banned now, and the lower chain ones are on the way out also, as they also
linger in the environment. Making them directly is nearly impossible without complex equipment. I have heard of taking the bromoperfluoroalkane
and make the Grignard, then reacting it with SO2 to generate the sulfonic acid. But that SM might also be hard to find, but not impossible.
|
|
|
wg48temp9
National Hazard
Posts: 786
Registered: 30-12-2018
Location: not so United Kingdom
Member Is Offline
|
|
Apparently 1,3,3,3-Tetrafluoropropene is available as a freeze spray in the UK and probably in other countries as well. For example Artic Spray from
ToolStation, 150ml for £11.50. As it contains a double bond I guess its relatively reactive so it may be convertible to a sulphonic acid without too
much difficulty.
I also thought it could be polymerized but I wanted to check that. According to several patents yes it can be polymerized for example:
Emulsion Polymerization
"In certain embodiments, the present invention relates to an emulsion polymerization method to produce poly-1234yf. While not limited thereto, the
polymerization may be performed using at least one radical initiator provided in an aqueous emulsion solution.
The radical initiators may include any compound that provides free radical building blocks for 2,3,3,3-tetrafluoropropene polymerization. In one
preferred aspect, the radical initiator is a persulfate compound or salt thereof. In certain preferred aspects, the persulfate initiators include, but
are not limited to, one or a combination of (NH4)2S2O8, K2S2O8, Na2S2O8, Fe2(S2O8)3, (NH4)2S2O5/Na2S2O5, (NH4)2S2O8/FeSO4, (NH4)2S2O8/Na2S2O5/FeSO4,
and the like, as well as combinations thereof.
The polymerization may be conducted in any aqueous emulsion solutions, particularly aqueous emulsion solutions that may be used in conjunction with a
free radical polymerization reaction. Such aqueous emulsion solutions, in certain preferred embodiments, include, but are not limited to, one or a
combination of degassed deionized water, buffer compounds (such as, but not limited to, Na2HPO4/NaH2PO4) and an emulsifier (such as, but not limited
to, C7F15CO2NH4, C4F9SO3K, CH3(CH2)11OSO3Na, C12H25C6H4SO3Na, C9H19C6H4O(C2H40)10H, or the like)."
From:- https://patents.justia.com/patent/20170240666
[Edited on 3/21/2021 by wg48temp9]
I am wg48 but not on my usual pc hence the temp handle.
Thank goodness for Fleming and the fungi.
Old codger' lives matters, wear a mask and help save them.
Be aware of demagoguery, keep your frontal lobes fully engaged.
I don't know who invented mRNA vaccines but they should get a fancy medal and I hope they made a shed load of money from it.
|
|
|
Dr.Bob
International Hazard
Posts: 2751
Registered: 26-1-2011
Location: USA - NC
Member Is Offline
Mood: No Mood
|
|
You can buy hexafluoropropene by the cylinder full. I think it is a by-product of PTFA production. Even more fluoriny. You can react that with
CoF3 to make octafluroropropane.
|
|
|
B(a)P
International Hazard
Posts: 1139
Registered: 29-9-2019
Member Is Offline
Mood: Festive
|
|
Quote: Originally posted by Nitrous2000  | Hey Folks,
Anyone have any experience with making/obtaining this compound? I have seen some posts around Nafion, and commenting on cost. But nothing around
substitutes....
Has anyone looked at the use of ion-exchange resins as a substitute? There are fluoro sulfonate based resins, but they are 1) very expensive and 2)
difficult to obtain.
Any suggestions that don't start with perfluorsulfonic acid would be appreciated
Thanks
Doug |
I spend my days trying to work out how to destroy and or remove these compounds from the environment and here you are trying to make it!
I am curious to know why you want to make it? They are basically ubiquitous in the environment at ppt - ppb concentrations. Go to your nearest Defence
site and collect as much surface water as you can down stream of the base. Put that water on high porosity (1000 iodine value) GAC to extract it from
the water. Then it is over to you, from here I would be looking at methods to destroy the PFSAs.
|
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
