Dynamics of carbon dioxide breakthrough in a carbon monolith over a wide concentration range

Monoliths, and structured column packings in general, offer the advantage of allowing increased throughput and reduced pressure drops. The performance of a monolith is commonly based on models of an equivalent characteristic channel representative of the system. The HETP or the dispersion of a breakthrough curve are indicative of the separation efficiency of an adsorption column, and what is typically observed is that the experimental results are below expectation. We present a detailed model that we have developed recently, which takes into account the distribution of the size of the monolith channels, the distribution of the wall thicknesses as well as the number of monolith sections in the column. In this contribution, the mathematical model is extended to include nonlinear isotherms and a procedure to determine the equilibrium parameters from a modified moment equation is applied to characterise the system CO(2) on a carbon based monolith. Model predictions, based on independently measured kinetic parameters, are shown to provide an excellent match to the experimental results over a wide range of gas phase concentrations.