638 Mr. A. F. Dufton on the Separation 



From these four equations it follows that 



dA - dV a 



dh a dh 



= 1 + 



= 1 



v h . l; 



=i-k, 



if there be equilibrium between liquid and vapour : 



1 dha 



a dh 



1 



that 



is. 



dh 

 dA 



cc[k~l) 



hei 



dh. 



i -j- is the total flow of liquid at the point 



dV 

 dA 



1 + 



'/A 



I* 



(3) 



(4) 



where ,,- is the total flow of vapour. 



The upper portion of Table I. shows the necessary flosv for 

 the separation of one gram of benzene from a mass of a 

 50-per-cent. mixture of benzene and toluene. 



Table I. 



Temp. 

 °C. 



per cent, 

 in liq. 



Grams Vapour 



passing up 



C ( .H + C T I-J 8 =total. 



Grams Liquid 



flowing down 



C e H t , + T H 8 =total. 



802 



100 



1-64 + 0-00 = 1-64 



0-64+0-00=0-64 



81-8 



90 



1-65 + 0-07 = 1-72 



0-65+007=0-72 



83-5 



80 



1-65 + 0-16= 1-81 



0-65+0-16=0-81 



854 



70 



1-66+0-28 = 1-94 



0-66+0-28=0-94 



87-6 



00 



1-66+0-44=2-10 



0-66+0-44=1-10 



900 



50 



1-66+0-66=2-32 



66+0-66=1-32 



93-0 



40 



1-67 + 1-01=2-68 



0-67+1-01 = 1-68 



96-4 



30 



1-68 + 1-57=3-25 



0-68+1-57=2-25 



100-4 



20 



1-70+2-80=4-50 



0-70+2-80=3-50 



105-0 



10 



1-72 f 6-43=8-15 



0-72+6-43=715 



110-6 







L75+ oo = co 



075+ co = oo 



