.
Now to separate solute (B) form (C) the following conditions must be met,
(6)
and 
(7)
Having established the down-flow of stationary phase the conditions defined in equations (6) and (7) must be met by adjustment of (QG(2)) and (T(2)). In a similar manner, using suitable restrictions, the pressures at the sample inlet and that of the outlet for solute (B) must be made equal (or close to equal) to reduce cross-flow.
Finally, solute (C) can be recovered under the following condition,
(8)
Courtesy of Benzole Producers Ltd. (ref.7)
Figure 27 The Extraction of Pure Benzene from Coal Gas by continuous Extraction Using a Moving Bed Technique
