Retention of stationary phase and partition efficiency of multilayer helical column rotated around its horizontal axis

Using a multilayer helical separation column coaxially mounted on a horizon tal rotary shaft, retention of the stationary phase and partition efficienc y were studied at various rotation speeds ranging from 20 to 800 rpm. A bin ary two-phase solvent system composed of chloroform/water was used to elute the lower organic phase through the head of the rotating column. The resul ts indicated that best retention of the stationary phase was obtained at a low rotation speed of 75 rpm yielding the highest peak resolution between c affeine and theophylline. Because of its simplicity and low rotation speed, the system has a potential to be scaled-up for an industrial-scale separat ion simply by increasing the capacity of the helical column.