Accurate blank corrections for zero length column experiments

Abstract

In this study we present a new methodology for correcting experimental Zero Length Column data, to account for contributions to the measured signal arising from extra-column volumes and the detector. The methodology considers the experimental setup as a series of mixing volumes with diffusive pockets whose contributions to the overall measured signal can be accurately described by simple model functions. The composite effect of the individual contributions is subsequently described through the method of convolution. It is shown that the model parameters are closely related to the physical characteristics of the setup components and as such they remain valid over a range of process conditions. The methodology is firstly validated through fitting to experimental experiments without adsorbent present. The inverse procedure of deconvolution can in turn be applied to experimental data with adsorbent, to yield corrected data which can readily be modelled using standard tools for equilibrium and kinetic analysis. A number of case studies is finally presented exemplifying the effect of applying accurate blank corrections, demonstrating also the application to a nonlinear adsorption system.

Structural Chemistry, Flexibility, and CO2 Adsorption Performance of Alkali Metal Forms of Merlinoite with a Framework Si/Al Ratio of 4.2

“…Prior to ZLC measurements, the samples were activated overnight at 523 K (Na 6.2 -, Cs 6.2 -MER) or 573 K (K 6.2 -MER) under a flow of helium. The as-received signals were corrected to account for effects which are intrinsic to the experimental setup, by means of a deconvolution procedure as described in Verbraeken et al 30 This procedure yields the concentration of the gas as it leaves the column and removes extra-column contributions, such as those arising from the detector. The materials' potential for gas separation was tested via breakthrough experiments.…”

Cation Ordering and Exsolution in Copper‐Containing Forms of the Flexible Zeolite Rho (Cu,M‐Rho; M=H, Na) and Their Consequences for CO2 Adsorption

“…To enable analysis of both breakthrough and ZLC results, blank runs were also carried out [51] . These consist of repeating the column experiments under the same conditions as described above, but without adsorbent.…”

“…To enable analysis of both breakthrough and ZLC results, blank runs were also carried out. [51] These consist of repeating the column experiments under the same conditions as described above, but without adsorbent. In this case the column is filled with 2 mm glass beads to give a pressure drop and void fraction close to that observed in the presence of the samples.…”

A quantitive microscale dynamic column breakthrough apparatus for measurement of unary and binary adsorption equilibrium on milligram quantities of adsorbent

“…Of additional importance is the extra-column volume upstream of the bed. The upstream volume from the valve to the bed should be fully swept so as to avoid the complications associated with stranded pockets of gas which can complicate the analysis of the breakthrough curves [31]. To meet these requirements, a Bronkhorst Mini-Cori M12 coriolis mass flow meter (200 ± 0.02 g/hr) was installed upstream of the adsorbate gas mass flow controller, MFC-2.…”