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Vapor Pressure Data Hunt 1

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fbrwiz33

Chemical
Joined
Jul 29, 2008
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US
I am looking for vapor pressure data for a Naphtha fraction sold as a plastic extrusion aid. I have a CAS number but it isn't getting me anywhere yet. Does anyone have suggestions as to where to look or how to proceed? This isn't a pure compound but a blend of components. Is there a way to estimate this. I found some Naphtha data but it isn't the right MW or boil pt.
 
To characterize a product you need:
- the specific gravity
- the boiling point (pure component) or the mean average boiling point temprature ie Tmav (petroleum cut).

Maxwell correlations are only useful for "wide" petroleum cuts. For "thin" ones, Tmav can be evaluated by the arithmetic mean value of the initial end and end boiling point temperature of the TBP distillation: Tmav=(IBP+EBP)/2.

Now, you probably want the True Vapor Pressure (TVV) at temperature T. Knowing the Reid Vapor Pressure (RVP measured at 37.8ºC and given in gage pressure), the ASTM distillation curve, T and using the Coordination Research Council corrrelation (via an abacus), you can access the TVV at T (absolute pressure).

Hope it helps

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