Shock effects in nonlinear chromatography

Journal Article · Thu Dec 01 04:00:00 EST 1988 · Anal. Chem.; (United States)

DOI:https://doi.org/10.1021/ac00174a022· OSTI ID:6417229

Lin, B; Golshan-Shirazi, S; Ma, Z; Guiochon, G

Shocks are discontinuities of a function that appear under certain sets of experimental conditions, such as a shock wave. This ideal concept has to be completed by the more realistic notion of shock layer. In a shock layer the function (pressure for a shock wave, concentration in chromatography) varies very steeply, and all the points in the shock layer (e.g., in a concentration profile) move at almost the same velocity as the shock itself would in the ideal case. In nonlinear, ideal chromatography, the behavior of elution band profiles starts to deviate markedly from what takes place in linear chromatography as soon as a concentration shock forms. Under the influence of the axial diffusions and the mass transfer kinetics the actual band profiles deviate from those predicted by the ideal model. The shocks are replaced by shock layers, but their positions and migration rates are modified only very slightly. The importance of these shocks on the shape and migration rate of the bands is dramatic. Classical concepts such as those of retention time, column efficiency, and resolution must therefore be analyzed within the framework of the shock theory.

• Research Organization: Univ. of Tennessee, Knoxville (USA)
• OSTI ID: 6417229
• Journal Information: Anal. Chem.; (United States), Journal Name: Anal. Chem.; (United States) Vol. 60:23; ISSN ANCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400102* -- Chemical & Spectral Procedures
BOUNDARY LAYERS
CHEMICAL ANALYSIS
CHROMATOGRAPHY
DIFFUSION
LAYERS
MASS TRANSFER
MATHEMATICAL MODELS
NONLINEAR PROBLEMS
PULSE TECHNIQUES
QUALITATIVE CHEMICAL ANALYSIS
SEPARATION PROCESSES
SHOCK WAVES
STRATIFICATION