6 replies to this topic

[nannanine]

helo

I want to separate hydrogen from liquid, so I want to ask on how to determine the temperature and pressure in a separator to separate hydrogen from a mixture of fatty alcohol, methanol, and methyl ester. thank you.

[shvet1]

Find H2 Henry's low constants for these materials. Check NIST database if you have an access to AspenOne.

[breizh]

Hi,

Consider this table for H2 Henry's coefficient.

Pay attention to the units.

Breizh

[nannanine]

thank you for answering to my question.

i want to ask again about what kind of separator can i use to separate the hydrogen from a liquid mixture if I use the henry law coefficient?

thank you

Hi,

Consider this table for H2 Henry's coefficient.

Pay attention to the units.

Breizh

[breizh]

Hi,

Is it a continuous process or a batch process? check for boiling points of your components.

what is the composition of the feed?

 

what is the specification of the final product?

 

It should be a distillation, right?

 

Breizh 

[nannanine]

I am a chemical engineering student working on my final project, which involves designing a fatty alcohol plant using a hydrogenation process with methyl ester as the feedstock and hydrogen. The liquid phase hydrogenation process is conducted continuously. However, I am facing challenges in separating hydrogen from the mixed product stream coming out of the hydrogenation reactor. Previously, I attempted to use flash calculation to determine the temperature and pressure in the separator, but the results indicated a negative temperature and excessively high pressure. I aim to achieve complete separation of hydrogen from the product mixture. Therefore, I would like to know how to select the appropriate separator and the calculations needed to ensure the efficient separation of hydrogen from the product mixture. 

the boiling point of the components in the separator:

h2 = -252,76 C

methyl ester = 417 C

fatty alcohol = 344 C

methanol = 64,7 C

 

 

thank you for your help

Hi,

Is it a continuous process or a batch process? check for boiling points of your components.

what is the composition of the feed?

 

what is the specification of the final product?

 

It should be a distillation, right?

 

Breizh 

[Pilesar]

 

 I aim to achieve complete separation of hydrogen from the product mixture. 

 

Aim at 'mostly separation' instead of 'complete separation'. What do you find as the hydrogen content in the liquid? Calculate the composition at the temperature and pressure of your process. What real harm is there with miniscule H2 in the liquid? Is it really economical to try to remove more H2? Trace components in your system is real life. 100% purity is not real life.