Adsorbents for Dilute CO and N2 Removal

The commercial performance of a H2 PSA process (online time, productivity, product purity) is generally dictated by the adsorption characteristics of the most 

An extensive study of optimum adsorbents for CO and N2 removal from SMROG for H2 production revealed that the use of highly Ca-exchanged, binderless A zeolite in the product end of the PSA column could increase the H2 productivity by -10% and the overall H2 recovery by -1.0 percentage point compared with those for a standard 5A zeolite (-70% Ca-exchanged NaA zeolite) when N2 in the product 

The majority of the published literature on improved adsorbents for H2 purification by PSA deals with equilibrium adsorption properties (adsorption capacities of the impurities and their selectivities over H2) of the materials. The adsorbents are generally chosen in such a way that the kinetics of adsorption of the impurities into the adsorbents are relatively fast, primarily being controlled by macro- and mesopore diffusion within the adsorbent particles. The kinetics of adsorption may, however, become an issue for the removal of the trace amounts (ppm) of a relatively weakly adsorbed impurity (N2 or CH4) at the product end of an H2 PSA due to the existence of a very low driving force for the adsorption process. It was suggested that a layer 

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