Speed of Analysis

The analysis time in chromatography for a given solute is calculated from:

-'-'min

2dp

uopt

3Dm

-'-'min

= 0.1 d-

uopt

Dm

On the other hand, speed of analysis is of no value if resolution, i.e. plate number, is insufficient. For equal pressure drops across capillary (maximum plate number Nc) and packed (maximum plate number Np) columns:

Np dr

The relative speed of analysis of packed and capillary column SFC may be compared by means of the parameter Hmm/wopt. For values of k between 1 and 5:

For equal speeds of analysis, therefore, dc = 2.6dp. For a given separation, it follows that analysis on currently available capillary columns with i.d. 50 |im is much slower than on columns packed with 3 or 5 |im particles.

Hence, from this analysis, a 50 |im capillary generates 450 times as many plates as a column packed with 5 |im particles. However, if N is set at 5000 plates for both columns, a typical ratio of analysis times would be 2.5 in favour of the packed column.

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

Get My Free Ebook


Post a comment