GC024 The Original Van Deemter Equation: Packed columns

Van Deemter identified three effects that contribute to peak broadening in packed columns:

Eddy diffusion (term A), longitudinal molecular diffusion (the term B) and mass transfer in the stationary phase (the term C). The Van deemter Equation is:

H = A + B/µ + Cµ

Where H is the plate height, and µ the linear gas velocity. A small value indicates a narrow peak (the desired condition). Minimize each term is the way to maximize column efficiency.

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