TY - JOUR

T1 - An Approximate Expression for the Minimum Plate Height Produced by Knox's Equation

AU - Carr, Peter W.

AU - Sun, Lifang

PY - 1998

Y1 - 1998

N2 - The van Deemter (h = A + B/v + Cv) and the Knox equations (h = av1/3 + b/c + cv) are the most widely accepted equations for describing the dependence of the plate height on mobile phase linear velocity. The simple form of the analytical solution for the minimum plate height obtained from van Deemter's equation allows one to locate the optimum velocity and minimum plate height and to obtain insight into the contribution of A, B, and C terms to the minimum plate height. Although Knox's equation provides better fit s to liquid chromatography data than van Deemter's equation, the exact solution of the minimum plate height based on Knox equation is too complicated to be informative. In this work, we describe a simple approach to estimating the minimum plate height based on Knox's equation. For typical HPLC conditions, the relative error of the estimates is generally less than 3%. The approximate analytical solution for the minimum plate height based on Knox's equation indicates the important contribution of the column packing term to the minimum plate height.

AB - The van Deemter (h = A + B/v + Cv) and the Knox equations (h = av1/3 + b/c + cv) are the most widely accepted equations for describing the dependence of the plate height on mobile phase linear velocity. The simple form of the analytical solution for the minimum plate height obtained from van Deemter's equation allows one to locate the optimum velocity and minimum plate height and to obtain insight into the contribution of A, B, and C terms to the minimum plate height. Although Knox's equation provides better fit s to liquid chromatography data than van Deemter's equation, the exact solution of the minimum plate height based on Knox equation is too complicated to be informative. In this work, we describe a simple approach to estimating the minimum plate height based on Knox's equation. For typical HPLC conditions, the relative error of the estimates is generally less than 3%. The approximate analytical solution for the minimum plate height based on Knox's equation indicates the important contribution of the column packing term to the minimum plate height.

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U2 - 10.1002/(SICI)1520-667X(1998)10:1<149::AID-MCS19>3.0.CO;2-Z

DO - 10.1002/(SICI)1520-667X(1998)10:1<149::AID-MCS19>3.0.CO;2-Z

M3 - Article

AN - SCOPUS:0347658714

SN - 1040-7685

VL - 10

SP - 149

EP - 152

JO - Journal of Microcolumn Separations

JF - Journal of Microcolumn Separations

IS - 1

ER -