Extra Column Dispersion - Dispersion in Contemporary LC Columns > Page 5

 

Thus,  and (1)

Consequently the Volume variance of the peak () is given by,

  (2)

Table 1. Properties of Three Common Types of Contemporary LC Columns

 

Column 1 2 3
I.D. (mm) 4.6 3 1
Length (cm) 3 10 20
Part. Diam. (mm) 3 5 10
Flow Rate (ml/min) 1 0.5 0.020
Efficiency (n) 6250 12500 6250
Ther.Dead Vol (ml) 0.299 0.424 0.094
(ml) 3.78 4s = 15.1 3.79 4s = 15.2 1.19 4s = 4.76
(ml2)   1.43 x 10-5   1.44 x 10-5   1.41 x 10-6
(ml) 22.68 22.74 7.14
(ml2)   5.15 x 10-4   5.18 x 10-4   5.08 x 10-5
(ml) 1.19 4s = 4.76 1.20 4s = 4.8 0.38 4s = 1.52
(ml2) 1.43 x 10-6 1.44 x 10-6 1.42 x 10-7
Vi (k'=0) 5.0 5.0 1.57
Vi (k'=5) 30.0 30.0 9.42
Practical Vi (k'=0) 0.87 0.88 0.27
Practical Vi (k'=5) 5.24 5.25 1.65
Practical Vi (k'=0) Capill. Col.100mm 0.073 ml Capill. Col.200mm 0.412 ml Capill. Col.300mm 0.760 ml
Practical Vi (k'=5) 0.746 ml 4.219 ml 7.784 ml