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Specialty Chemistry Forums => Chemical Engineering Forum => Topic started by: seshwanth on August 23, 2007, 06:58:00 AM

Title: reg absorption column
Post by: seshwanth on August 23, 2007, 06:58:00 AM
My question is, for a absorption column to be effective or for the seperation to be effective how should the temp and pressure be? wheather temp and pressure should be high? with a valid reason ? . same as in the case of adsorption column?
thank u 
Title: Re: reg absorption column
Post by: Mr Peanut on August 23, 2007, 08:52:36 PM
I hate to answer a question with questions but it really does matter.

Your phase is liquid or gas?

Your absorbent is activated carbon, SDVB, zeolite, prep chromatography bed (type), sodium metal, other?

The component you want to absorb is?

The mobile phase (the thing you are not absorbing) is?
Title: Re: reg absorption column
Post by: Montemayor on August 23, 2007, 10:45:45 PM

I hate to bring up basics when I believe everyone reading this knows the difference between the Unit Operations of Absorption and Adsorption, but I'll do it anyway because I think this thread will die from confusion if I don't.

Adsorbents such as "activated carbon, zeolite, prep chromatography bed (type), sodium metal", and others have nothing whatsoever to do with Absorption.  Solid adsorbents do not absorb.  Using either term in place of the other will lead to mass confusion.  The two Unit Operations are very, very different and should be understood by all reading this thread.

The conditions of temperature and pressure in an absorption column usually are set by the process in question.  Normally, the higher the pressure - the better the absorption factor; the lower the temperature, the better the absorption factor.  But those are only generalities.  Sometimes, such as in the case of CO2 absorption with an MEA solution can cause problems if the CO2 originates in a condensable hydrocarbon stream.  Some of the hydrocarbons can condense with a lower temperature in the absorption column and cause a serious MEA solution contamination and cause foaming and other problems in the absorber and in the stripper.  So it all depends on the Process and also on the chemistry in question.

Basically, your question is too general or vague and you need to be specific if you have a case in mind.   If you don't have a specific case in point, then you can only speculate.

Title: Re: reg absorption column
Post by: JoeWong on August 24, 2007, 02:38:59 AM

I believe if you read those chapters in Perry engineering handbook or any good operation unit book and think a little bit more, you will have the idea of how pressure & temperature affect the separation process.

Also you may search online e.g. google, wikipedia, etc. You may find some answers.



Also read HERE...

Mr. Montemayor,
We may just provide general response to general question.
There are some question even worst..."What is a logic ?". For this kind of question, i will choose to ignore.

Title: Re: reg absorption column
Post by: seshwanth on August 24, 2007, 09:05:45 AM
Thanks for all those u fired me. anyway i hav to thank for reply and giving me a solution. i am just a beginner in chemical engg.

with regards