Small particle liquid chromatography flow rate

An alternative strategy for fast liquid chromatography uses short columns packed with small particles operated at high flow rates and often elevated temperatures to separate simple mixtures under conditions were resolution is compromised but still adequate for identification purposes [252-258]. Small diameter particles provide larger plate numbers by virtue of their relatively small interparticle mass transfer resistance combined with a shallow increase in the reduced plate height as the reduced mobile... 

High-Performance Liquid Chromatography. The difference between classical LC and HPLC can be explored by referring to Figures 21.13 and 21.14. For classical LC, large porous particles with dp = 100-250/ m (Fig. 21.13A) are packed into columns with internal diameters of 1-5 cm (Fig. 21.14A). Little pressure is required to permit slow solvent flow between these large particles. Normally, a small head of liquid in the column above the surface of the packing or, in some cases, a reservoir container connected to and placed above the column acts as the constant-pressure source. Pressure drops are of the order of 0.1-1 atmosphere. Flow rates are very... 

In modern chromatography, the separation columns are tightly packed with small particles of about 1-5 pt m in diameter. To achieve ambient flow rates in these columns, high pressures of up to 300-400 bar must be generated. A typical instrumental setup for this high pressure or high performance liquid chromatography HPLC) is shown in Fig. 2.6. 

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