Toluene-Water system in Aspen
Toluene-Water system in Aspen
(OP)
Hi all, I am Eng.Antonio Aulicino (University Federico II of Naples, Italy). I am using Aspen Properties to understand what is the suitable property method for a system with toluene and water. I do the Txy diagram and xy diagram, but i didn't found a property method that gives results in agreement with literature.
-What is the property method correct for toluene-water?
In the manual there is:
"For water-hydrocarbon applications, two liquid phases often coexist with a vapor phase. Aspen Properties has two approaches for modeling these types of vapor-liquid-liquid equilibrium calculations:
·Rigorous three-phase calculations
·Calculations with a free water approximation. When you use free water approximation, Aspen Properties assumes the water phase is pure liquid water (free water)."
What i have to do
-How i can do the rigorous three-phase calculations?
My first target is to design an absorber column for toluene with pure water. The second, and most important target, is to design an absorber column not with pure water, but with a solution of water and copolymer that enhanced the solubility of toluene in water.
-Is it possibile to change in Aspen, only some properies of water (such as the viscosity and the solubility of toluene)?
Thanks all
-What is the property method correct for toluene-water?
In the manual there is:
"For water-hydrocarbon applications, two liquid phases often coexist with a vapor phase. Aspen Properties has two approaches for modeling these types of vapor-liquid-liquid equilibrium calculations:
·Rigorous three-phase calculations
·Calculations with a free water approximation. When you use free water approximation, Aspen Properties assumes the water phase is pure liquid water (free water)."
What i have to do
-How i can do the rigorous three-phase calculations?
My first target is to design an absorber column for toluene with pure water. The second, and most important target, is to design an absorber column not with pure water, but with a solution of water and copolymer that enhanced the solubility of toluene in water.
-Is it possibile to change in Aspen, only some properies of water (such as the viscosity and the solubility of toluene)?
Thanks all





RE: Toluene-Water system in Aspen
Depending on the nature of the water/copolymer mixture data, it may be possible to create a hypothetical water also.
Good Luck. It's not an easy problem.
--Mike--
RE: Toluene-Water system in Aspen
There are news. With Aspen Properties I found a property method that appears to be suitable for water-toluene: UNIFAC (or UNIQUAC) + free water calculations. But it is clear that I can not use the free water calculation if I want to do an absorber column, so I thought, as you said Mike, to change the Henry's constant for the toluene in water (from the literature), and then, when I will use the solution water/copolymer, i will change another time the Henry's constant...i will try to do this tomorrow because I have just returned from the university and I am tired.
In Aspen I have never changed properties in a property method, so If you have any advice I would be very happy; however, tomorrow I will try reading the manual.
Thanks all
RE: Toluene-Water system in Aspen
Sorry I can't be of more help.
--Mike--
RE: Toluene-Water system in Aspen
RE: Toluene-Water system in Aspen
In the past, I used UNIQUAC with ASPEN, on this system, with success.
could you attach you input file and the data you want to fit? We could have a look.
RE: Toluene-Water system in Aspen
Thanks all