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Specialty Chemistry Forums => Biochemistry and Chemical Biology Forum => Topic started by: Black_Forest on August 14, 2006, 08:27:14 PM

Title: working with NaF and KF
Post by: Black_Forest on August 14, 2006, 08:27:14 PM
Hi!
I would like to ask if you have some experience how is to work with NaF and KF at 1000°C but in the lab not under fumecoboard.
I know that is toxic but I do not see at the moment how to protect myself since the lab is not well equipped
Thank you for your advice!
Title: Re: working with NaF and KF
Post by: woelen on August 18, 2006, 05:06:46 PM
If you want to use NaF and/or KF at 1000 C, and if you don't have any protection, then PLEASE DON"T DO THIS!

Fluorides are insidiously toxic and really nasty. At ordinary temperatures, NaF and KF are not that dangerous, but on addition of even weak acids, the VERY dangerous HF is formed, but at temps of 1000 C or so, you may have some volatility of the fluoride.

Many people think of fluoride, just as the other halogenides (chloride, bromide, iodide), but this is a big mistake. The other halogenides are almost non-toxic (at least, if the cation is non-toxic) and their acids, although corrosive, are not long-term toxins and only are toxic due to their corrosiveness. The fluorides and the acid HF are of a totally different nature and the concentrated acids HCl, HBr and HI are childrens toys, compared to HF or hot metal fluorides. Some of the greater 19th century chemists (Davis, Moissan, Scheele) have suffered from very severe health problems due to fluoride poisoning over a longer time and IIRC some of these great chemist died a prematurely due to the bad effects of fluoride poisoning.
Title: Re: working with NaF and KF
Post by: Black_Forest on August 20, 2006, 05:33:47 PM
woelen,

I agree with you.
When I was PhD student in G****** people were paying much attention to such things but now, in U** I cannot believe that is allowed to work in such bad conditions in a such prestigious school.
Personally I have no motivation to work and I feel very bad.
Title: Re: working with NaF and KF
Post by: Borek on August 20, 2006, 05:40:36 PM
When I was PhD student in Germany people were paying much attention to such things but now, in USA I cannot believe that is allowed to work in such bad conditions in a such prestigious school.

AFAIK Americans can be quite paranoid about safety so it sounds incredible. Can you share some details?
Title: Re: working with NaF and KF
Post by: Black_Forest on August 20, 2006, 10:13:33 PM
you ask me
Can you share some details?
say which details do you want more precisely  ;D
Title: Re: working with NaF and KF
Post by: Borek on August 21, 2006, 02:55:28 AM
say which details do you want more precisely  ;D

such prestigious school.

Which school and who asks you to work in such conditions - but I see you have already started to hide facts editing earlier posts.
Title: Re: working with NaF and KF
Post by: Black_Forest on August 21, 2006, 12:16:29 PM
you are right.

I cannot say, but it is true what  is happen
Title: Re: working with NaF and KF
Post by: Borek on August 21, 2006, 12:28:44 PM
you are right.

I cannot say, but it is true what  is happen

Sorry, but I don't buy it. I am more then sure that in every school there are people responsible for lab safety and that you can contact them if you are asked to do things you feel dangerous.
Title: Re: working with NaF and KF
Post by: Black_Forest on August 25, 2006, 02:21:30 PM
 :-[
one hole from the upper part was open and I had "opportunity" to breath some white dust at 1000^C!
Title: Re: working with NaF and KF
Post by: Borek on August 25, 2006, 02:27:17 PM
:-[
one hole from the upper part was open and I had "opportunity" to breath some white dust at 1000^C!

And you should immediately report it to authorities.
Title: Re: working with NaF and KF
Post by: Black_Forest on August 25, 2006, 02:38:54 PM
this how you think!
but I am affraid to not loose my work !

it is a problem about the cultural  code ! the atitude! the fear!
Title: Re: working with NaF and KF
Post by: Borek on August 25, 2006, 03:18:26 PM
this how you think!
but I am affraid to not loose my work !

You prefer to loose health/life?
Title: Re: working with NaF and KF
Post by: english on August 31, 2006, 02:36:09 PM
:-[
one hole from the upper part was open and I had "opportunity" to breath some white dust at 1000^C!

Um that sounds pretty bad you might want to have that checked out.

I don't know much of fluorides nor have done any work with them but I do know that HF is capable of literally eating through your skin.  I don't know of this white dust you speak of but involving fluroride at temps of 1000°C, I know it's probably bad.