A Simple Approach to Sample Preparation for Accurate and Reproducible Gas Phase Breakthrough Analysis of Adsorbent Materials

A simple approach to sample preparation for gas phase breakthrough analysis of adsorbent materials such as metal–organic frameworks is reported. To circumvent issues related to particle size, MOF powders are coated onto glass beads using only the adhesion forces between the glass surface and the particles themselves. These coatings are sufficiently stable for the coated beads to be packed into columns and used for breakthrough measurements of the pure solids. Samples prepared in this manner are compared to analogous samples coated using a binder to attach the MOF to the surface of the beads. In many cases, the approach reported here achieves higher uptake capacities and longer breakthrough times than when a binder is used, presumably because the binder partially clogs the porous structure of the MOF. In addition, an example is discussed that highlights the possibility of a reaction between the sorbent and the binder, highlighting the advantage of a simplified sample preparation method that does not require additional chemical additives.