Equipment and Experimental Methods in HPIEC

The equipment used in HPIEC is different from that used in CIEC. The columns, valves, and pipes are exposed to high pressures. This requires them to be not only corrosion resistant to acids, bases, and other chemical agents, but they also need to be pressure resistant. Because of this, the materials used in their construction are required to be of higher quality than the material used to construct the CIEC devices. The devices, e.g., the column, valves, pipes, sieves, pressure vessels, and pressure gauges used by the authors, were primarily made of special stainless steel. Some junctions were made of polytetrafluoroethylene plastic. Usually the last column of a system of columns was made of glass so as to permit observation of the separation affected. 

The three-column system is primarily used in basic studies and simple separations. Important parameters and functions are listed in Table 4 while its configuration is shown in Fig. 1. 

Column number Material Function Cross section (cm Height of column (cm) Height of resin bed (cm) Diameter of resin (mm) 

M high pressure pump Vp pressure gauge B charing hooper C adsorption columns C2 C3 separation columns W1-W15 valves 

The first column provides the two essential functions of adsorption and separation. If the mixed species are easily separated lower column ratios are required and the loading capacity can be increased or reduced. For a basic study only the third column, a glass one, is used. The change of bandshape can, as a result, be directly observed while the migration rate of the separation band can be easily monitored by watching its movement in this glass column. 

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