Band broadening radial temperature gradients

Figure 3.11 Band-broadening due to thermal effects (a) thermally equilibrated, (b) negative radial temperature gradient with significant axial gradient, (c) positive radial temperature gradient with minor axial gradient. From Wolcott, R.G., et al. J. Chromatogr. A. 2000, 869 211-230, with permission.

The temperature gradient also affects the analyte diffusivity and retention on the column. Thus, both diffusivity and retention factors are a function of pressure and temperature. Frictional heating can cause a nonuniform increase or radial gradient in temperature inside a column, which can have a detrimental effect on the separation, resulting in band-broadening and poor peak shape (40,41). 

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