Quantitative Microscale Dynamic Column Breakthrough Apparatus for Measurement of Unary and Binary Adsorption Equilibria on Milligram Quantities of Adsorbents

Abstract

A microscale dynamic column breakthrough (μDCB) apparatus with the ability to measure unary and binary adsorption equilibria on a milligram-scale quantity of adsorbent is described. The μDCB is a low-cost system that can be constructed through minor modifications of a commercial gas chromatograph and uses a thermal conductivity detector. The small scale of the apparatus allows for the rapid collection of dynamic column breakthrough experiments. The mass balances for adsorption and desorption experiments were derived along with a description of the blank. The microscale dynamic column breakthrough apparatus was tested with 238.9 mg of zeolite 13X and 180.2 mg of activated carbon with single-component N2/He and CH4/He adsorption and desorption measurements. The measured equilibrium data agreed well with volumetrically collected data. These measurements are both accurate and precise. Multicomponent adsorption was also studied on zeolite 13X and activated carbon for CH4/N2 and CO2/CH4 mixtures. This data was compared with ideal adsorbed solution theory, extended dual-site Langmuir calculations, and the literature.