Hydrofloric Acid
Hydrofloric Acid
(OP)
Dear All,
I am testing out new materials for a project that I am working on and I have just been asked it they will stand up to attack by Hydrofloric Acid. From what I can tell there is very little that can stand up to this acid, but I need to know more about it first.
Where does it naturally occur?
Is it likely to be found with petroleum products?
General background on it.
If anyone can help I would be very grateful.
Regards,
John
I am testing out new materials for a project that I am working on and I have just been asked it they will stand up to attack by Hydrofloric Acid. From what I can tell there is very little that can stand up to this acid, but I need to know more about it first.
Where does it naturally occur?
Is it likely to be found with petroleum products?
General background on it.
If anyone can help I would be very grateful.
Regards,
John





RE: Hydrofloric Acid
RE: Hydrofloric Acid
http://hazard.com/msds/
I can't think of anywhere it occurs naturally. (Doesn't mean it doesn’t)
If you are going to play with Fluorine compounds you need to be careful of more than just HF. HF is the famous, bad one but there are lots of other fluorine compounds that are nasty to very nasty.
Try Google. Esp. http://gnp.enviroweb.org/hf1.htm
tom
RE: Hydrofloric Acid
Thanks for the tips.
John
RE: Hydrofloric Acid
Fuels.
2. Aluminium, Carbon Steel and Monel all resist attack by HF
and the plants generally are made of these materials.
3. Do Not use Stainless Steels or Silicone Gaskets, they have no resistance.
4. 'HF' Acid is unstable, and is classed as a 'Fuming' Acid,
it readily and rapidly causes vapour clouds at ambient temperatures and atmospheric pressures
5. It is theoretically possible for Trace Residues to find their way offsite in the fuels, but unlikely to accumulate in vehicle fuel systems in any meaningful quantity, however
they could accumulate in storage tanks over a period of time if the conditions were right.
RE: Hydrofloric Acid
RE: Hydrofloric Acid
I don’t want to test with any new acids until I know if there is a chance it could appear naturally in a well bore.
If anyone has any other thoughts on the subject then I would be happy to hear them.
Regards,
John McGrath
RE: Hydrofloric Acid
RE: Hydrofloric Acid
RE: Hydrofloric Acid
I have found out from another source in the Coiled Tubing industry that HF is used as an acidiser to clean out perforations and such like and that it is not naturally occurring in a well bore.
Thanks for everyone’s input.
Regards,
John McGrath
RE: Hydrofloric Acid
HF is far too reactive to remain present if it did form naturally. The fluoride ions will virtually react with anything to form a stable compound.
RE: Hydrofloric Acid
As mentioned, it is a nasty acid as it is odorless and looks like water. It attacks calcium and that is why when this acid is accidently spilt on a person, he has to be treated immediately before it penetrates into the skin and attack the bone.
RE: Hydrofloric Acid
These are Kynar-PVDF, Halar-ECTFE, Tefzel-ETFE, Teflon-FEP, Hyflon-MFA, Teflon-PFA and of course PTFE.
See the websites for Dupont, Ausimont, and Atofina for more information on these flouropolymers.
http://www.ausimont.com/docs/matl_plastics.html
http://www.atofinachemicals.com/kynarglobal/index.cfm
http://www.teflon.com/
For structural integrity, use corrosion resistant fiberglass with a flouropolymer lining.
RE: Hydrofloric Acid
www.symalit.ch a manufacturer of fluoropolymer sheet
www.ausimont.com manufacturer of fluoropolymer resins
http://www.dupont.com/teflon/chemical/tefz.html
remember HF permeates fluoropolymers so it is important to know the pressure and temperature so it can be proberly designed for and constructed for this phenomenon.
good luck!
RE: Hydrofloric Acid
I ran across this analyzing a brazing process. In the brazing process, apparently you just melted the braze alloy onto the carbide using a flux that traps oxygen. However the braze alloy was silver, copper, nickel, zinc and cadmium. The flux was organic salts of potassium and fluorine. The tungsten carbide had a cobalt binder as well as various trace materials. The heating was done with an oxy-acetylene torch (figure 5,000 F) in a saw shop atmosphere so figure standard atmosphere plus oil, grease, metal fines, etc. A process this sloppy with this much energy and this many chemicals meant that there was the possibility for all sorts of accidental compounds and reactions.
Just because you do not have pure HF does not mean that you do not have HF or HF like compounds created incidentally. Also as powerful as HF is it can be potentiated by the addition of other chemicals.
If you do a spectrographic analysis or similar and find Fluorine (other halogens, etc.) you might want to consider what can happen to it during the processing.
tom