manicmajor Posted May 4, 2006 Share Posted May 4, 2006 I tried looking up information regarding the BET Theory (http://en.wikipedia.org/wiki/BET_theory), but I was unable to find anything related to assumptions made from the BET Theory. Background: I'm doing a lab report on physical adsorption. A discussion question asks "Consider each of the five assumptions inherent to BET theory..." I understand the equation as listed in Wikipedia, but would anyone know assumptions that were made or can be pulled from the equation? Link to comment Share on other sites More sharing options...
encipher Posted May 4, 2006 Share Posted May 4, 2006 I think i can recall a few: 1. That the adsorbed molecules stay put 2. That the energy of absorbtion is the same for all layers except the first. 3. That the enthalpy of adsorbtion is the same for all the layers. If i remember any others Ill post. Link to comment Share on other sites More sharing options...
manicmajor Posted May 4, 2006 Author Share Posted May 4, 2006 That was what I was trying to figure out Link to comment Share on other sites More sharing options...
encipher Posted May 4, 2006 Share Posted May 4, 2006 I don't quite recall the fourth.. i beleive there are only 4... not 5. At least i dont remember a fifth. Anyways the forth has to do with the formation of layers.. but i dont remember. Should've paid more attention in class =\ Link to comment Share on other sites More sharing options...
encipher Posted May 4, 2006 Share Posted May 4, 2006 Well, I found this in a document on UFL's site: The B.E.T. theory is based on several assumptions: i) adsorbent consists of a regular array of adsorption sites equal in energy, with a constant enthalpy of adsorption in the monolayer, DHA ii) adsorption is localised to these sites iii) neighbouring adsorbed molecules do not interact iv) multilayer formation is unlimited v) enthalpy of adsorption in second and subsequent multilayers is equal to the enthalpy of liquefaction, DHL vi) adsorption or desorption may only occur on or from exposed sites. Link to comment Share on other sites More sharing options...
manicmajor Posted May 4, 2006 Author Share Posted May 4, 2006 What is UFL? Link to comment Share on other sites More sharing options...
encipher Posted May 4, 2006 Share Posted May 4, 2006 University of Florida . (actually it wasnt ufl.. wasnt wearing my glasses) here's the URL: http://www.staff.ncl.ac.uk/a.j.fletcher/isotherms.htm Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now