Cooling rate for WAT

[mrswax]

hello to all,

By using differential scanning calorimetry which perfect cooling rate does it use for measuring wax appearnce temperature, for measuring melting poing, 10°C/min is common used.
from my experience WAT affect by changing the cooling rate (e.g petroleum product), however some crude oils haven't this behaviour, so by having different values of WAT which cooling rate I should consider as a correct one.
If you have any idea about this area please let me know.
thanks

 

[25362]

As far as I know cooling rates and sensitivity act in opposite directions.

Looking at the following links may be of help:

ASTM E 793, E 1356, E 1953-02, D 6604-00, D 3418.

http://www.ifp.fr/IFP/fr/IFP02OGS.n...00553AF6/$file/coutinho_v54n5.pdf?openelement

http://www.engineeringreference.com/Properties/moreproperties.htm

 

[m777182]

It is an idea maybe that you could perform tests by a few (at least three) different cooling rates and extrapolate the temperature of wax appearance to zero cooling rate where actually you cannot measure it. It is the way I am using by solubility determinations.
m777182