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[Art Montemayor]

meri:

I assume you are seeking adsorption isotherms for the system of Activated Carbon adsorbing Propanol and Butanol for the purpose of designing the physical size of required fixed adsorption beds.

The source most reliable for design purposes is the actual Activated Carbon manufacturer whose product you intend to use in the fixed beds. The next option for the information is to run a pilot plant set-up of the proposed adsorption operation with a pre-selected adsorbent and measure the results yourself or have a laboratory do it for you (this can get expensive). The third option available isn't too reliable or accurate; it's what a student or an engineer doing a feasibility study with an expected error range of approximately 50% would do: pick a generic Activated Carbon and go to the published literature describing the exact operation or one with similar solutes (impurities) and use the published sorptivity with a contingency for assuring you're on the conservative side of the design. This third option is not one to use for a serious design; it is a measure used merely for feasibility or estimating reasons prior to deciding to seriously spend engineering study costs on a project.

You haven't given us the minimum information for adding more positive responses: is the system a fixed bed? is the system a liquid system? do you propose to adsorb the propanol & butanol at the same time? or will they be adsorbed step-wise, using different adsorbents? Are you stuck with using only Activated Carbon? Can you use Molecular Sieves? What type of cycles are you proposing or debating on using? How do you proposed to regenerate the beds?

Basically, if you are doing your engineering project for your Ch E degree in Barcelona, I believe you require some "credible" and substantiated basic data. Therefore, I recommed you go directly to Activated Carbon suppliers (actually, the manufacturer is the best source) and plead with them to help you identify the sorptivity that you can use for design. I caution you on using published isotherm data for design; you have to apply an empirical and experience factor to the sorptivity of the adsorbent for designing the actual, real-life adsorption capacity. I'm sure your profs know of this and will take you to task should you employ purely theoretical data for design.

I hope this helps you out and that it at least gets you started.

Art Montemayor
Spring, Texas