Vapour Pressure of Hexafluorobenzene 1

[natllc]

What would be the vapour pressure of Hexafluorobenzene at 553K (280C)

Bruce, Nichols Technology

 

[25362]

The NIST webbook provides the Antoine equation constants for up to 516.67 K. I wonder whether it would be acceptable to extrapolate to 553 K using Clausius-Clapeyron.

 

[PaoloPemi]

as you probably know at 553 K with pure Hexafluorobenzene you are above it's critical point (my software, Prode, returns for Tc 516.72 K),
for these cases I use the critical pressure (32.886 Bar.a according the same source) as limiting value.

 

[25362]

Paolo, a star for you. I missed that point.

 

[natllc]

Thanks, but to put it in real terms, we have 4cc Hexafluorobenzene contained in a sealed 4cc container operating at 90-100C but must be rated for short duration at 280C maximum. What would be the pressure @ 280C? Our problem is that there is a foil sealed opening in the container (for piercing at the appropriate time) and we are concerned the foil will not contain the pressure generated at the higher temperature.

Bruce, Nichols Technology

 

[Latexman]

Is it hydraulically full? If so and the liquid expands, the pressure can get quite high. Like a Gazillion Bar. More than enough to pop a foil seal.

Good luck,
Latexman

Need help writing a question or understanding a reply? forum1529

 

[Latexman]

Take a look at this thread for thermal expansion - thread124-171158

Good luck,
Latexman

Need help writing a question or understanding a reply? forum1529

 

[PaoloPemi]

if it's full of liquid you may estimate the max. pressure inside the container solving a system which considers

a) thermal expansion of liquid (and container)
b) compressibility of liquid and expansion (under pressure) of container

if possible I would recommend to leave a little vapor, this could solve many problems.

 

[natllc]

Thanks so much for the comments, you guys are great. Adding a vapour space would solve the problem but this is getting more complicated than I had first thought. It's obvious I will need to get someone to provide consulting for this. Thanks so much for your insights.

Bruce, Nichols Technology