Adsorption process design reliability

In the simplest type of adsorption processes in which an adsorption column is used to remove a trace impurity from a process stream, the main requirement for rational design is an estimate of the dynamic or breakthrough capacity of the bed. In such systems the adsorbable impurity is invariably strongly adsorbed with a favorable isotherm and the concentration profile therefore rapidly approaches constant-pattern form. The constant-pattern assumption provides the basis of a very simple design method which permits reliable scale-up from small-scale laboratory experiments. 

An apparatus with high sensitivity is the heat-flow microcalorimeter originally developed by Calvet and Prat [139] based on the design of Tian [140]. Several Tian-Calvet type microcalorimeters have been designed [141-144]. In the Calvet microcalorimeter, heat flow is measured between the system and the heat block itself. The principles and theory of heat-flow microcalorimetry, the analysis of calorimetric data, as well as the merits and limitations of the various applications of adsorption calorimetry to the study of heterogeneous catalysis have been discussed in several reviews [61,118,134,135,141,145]. The Tian-Calvet type calorimeters are preferred because they have been shown to be reliable, can be used with a wide variety of solids, can follow both slow and fast processes, and can be operated over a reasonably broad temperature range [118,135]. The apparatus is composed by an experimental vessel, where the system is located, which is contained into a calorimetric block (Figure 13.3 [146]). 

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