In the Aspen reactive distillation (NRTL) kinetic equation, is the concentration based on activity?
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This post was last edited by wuwei253273 on 2010-4-30 09:47 to perform reactive distillation calculations, using the NRTL property method. Among them, the gas-liquid composition is calculated based on the liquid-phase activity; then, for the reaction kinetic concentration in the liquid phase, is it based on activity or molar concentration? In Pro2, on the kinetic input page, the liquid phase concentration can be selected based on activity/concentration; however, this option is not available in Aspen. Since there are studies in which the kinetic equations are based on activity, this question arises. Thank you!
Personally, I think it should be based on activity, as most systems deviate from the ideal state; if it is calculated based on concentration, the simulation accuracy of Aspen will be significantly reduced.
This post was last edited by wuwei253273 on 2010-4-29 at 12:55. I understand it should be based on activity. But sometimes the kinetic equation used for searching is based on concentration, and in such cases it’s difficult to decide how to set it.
The NRTL property method is used to calculate activities; whether the kinetic concentration term in the liquid phase should be based on activities or molar concentrations depends on the choice made by the user This can be chosen in Reaction’s kinetic model as being based on activity or molar concentration.
The option [Ci]basis in Aspen was ignored. I understand now
What’s going on? I don’t understand 5# wuwei253273
In reactions-reactions-kinetic, among the options after [Ci]basis, there is an option based on activity. There are various reference concentrations here; please pay attention to the notes below.
The ASPEN reactive distillation has various concentration bases to choose from
Reply to 1# wuwei253273: Senior, are you still here? I have a question regarding the plug reactor.
It seems there’s no activity, right? It’s all about molar solubility, mole fractions, and things like that