Partial pressure claculations
Partial pressure claculations
(OP)
Can someone please guide me on partial pressure calculation for this applicaion.
I have a tank filled with acetone-polymer mixture(for simplicity I assume 100% acetone) and pressurized to 500 psig with hydrogen. What would be the partial pressure of hydrogen in the tank when the temperature is raised to 150 deg F. Pressure is maintained at 500 psig with a control valve.
Appreciate your help.
I have a tank filled with acetone-polymer mixture(for simplicity I assume 100% acetone) and pressurized to 500 psig with hydrogen. What would be the partial pressure of hydrogen in the tank when the temperature is raised to 150 deg F. Pressure is maintained at 500 psig with a control valve.
Appreciate your help.





RE: Partial pressure claculations
The total pressure is the sum of the two partial pressures of hydrogen and acetone vapor. If you know the saturation pressure of acetone at 150 F, that is its partial pressure. The remaining partial pressure is that of the hydrogen.
RE: Partial pressure claculations
best wishes,
sshep
RE: Partial pressure claculations
You have assumed "for simplicity" 100% acetone probably because the polymer has negligible vapor pressure. But if you have a solution of acetone and polymer, then the mol fraction in the liquid assuming an activity coefficient of 1.0 (which is not sure, I have encountered activity coefficients of 1.25 for acetone in non-electrolyte solutions at this level of temperatures) would have to be multiplied by the tabulated pressure to get the acetone contribution to the total pressure. Simply adding Raoult's law to the Dalton law for ideal solutions.
RE: Partial pressure claculations
You are right 25362. Vapor presuure of NBR rubber dissolved in acetone has no significant vapor pressure.Pressure control valve maintains 500 psi in the reactor as Hydrogen is being consumed.(hydrogenation on NBR rubber)
RE: Partial pressure claculations
Good luck,
Latexman
RE: Partial pressure claculations
Appreciate your comments.
Lab data on Vapor phase compostion is 98.5% in agreement with the calculated molar composition of Acetone and Hydrogen based on partial pressures. This clearly indicates that atleast in this process, NBR has no significant contribution to vapor pressure. 1.5% difference could be due to monomers in the NBR rubber that vaporizes.
RE: Partial pressure claculations
If I have acetone and water mixture(unknown composition from different sources) fed continuously to a tank at 4 psig( maintained by a PCV) and 201 deg F. What will be th e partial pressure of acetone?
Vapor pressure of acetone at 201 deg F is 46 psi.
Appreciate for educating me.
RE: Partial pressure claculations
Good luck,
Latexman