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Theory

 

The entropy per mole of an n-component ideal mixture is given by


 equation12
where tex2html_wrap_inline140 is the mole fraction of the ith constituent. If there are only two constituents, we have


eqnarray18

If the mixture has tex2html_wrap_inline144 moles of the second constituent, we get
equation22

The energy required to separate the mixture is


 equation25

For those who didn't follow the derivation, of (4), we summarize. R is the universal gas constant 8.314 joules per mole per degree Kelvin, T is the absolute temperature at which the separation takes place and x is the mole fraction in the mixture of the substance being extracted.



John McCarthy
Thu Aug 21 09:12:21 PDT 1997