Adsorption isotherm data for water vapor on F-200 7 × 14 Tyler mesh activated alumina are obtained at (5, 15, 25, and 35) °C in the range 0% to approximately 95% relative humidity using a static gravimetric technique. F-200 is a commercially available adsorbent that has become very popular in industry for drying compressed air via pressure or temperature swing adsorption. The equilibrium isotherms are presented in tabular as well as in graphical form. The equilibrium data are measured in both directions:  adsorption and desorption. A pronounced hysteresis between the adsorption and the desorption legs is present at all temperatures. When plotted versus the relative humidity, the equilibrium data are essentially independent of temperature. The complete removal of the adsorbed water requires regeneration at elevated temperature (290 °C) under vacuum. The data reported in this study can be used in industrial design as well as in the theoretical studies on the adsorption/desorption mechanisms of water vapor on activated alumina.

Single component adsorption equilibrium data for water vapor on commercially available activated alumina F-200 measured in a previous study (Serbezov, 2003) is correlated by two adsorption isotherm equations, both of which are based on the adsorption potential theory. The first equation is the well known Dubinin-Astakhov (D-A) equation. The second equation is obtained from a methodology proposed by Kotoh et al. (1993). It is referred to as a dual mechanism adsorption potential (DMAP) equation because it is a linear combination of two D-A terms with n = 1 where each term accounts for a specific mechanism of water retention. The D-A equation has two fitting parameters; the DMAP equation has three fitting parameters. The DMAP model provides a better fit for the adsorption data than the D-A model, while neither model describes the desorption data well. Analysis of the DMAP equation parameters shows that most of the water is retained by virtue of capillary condensation. In addition to fitting the experimental data, the heat of adsorption was calculated as function of the relative humidity and adsorbent loading. When capillary condensation is present, the heat of adsorption is only slightly higher than the latent heat of vaporization.

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A comprehensive theoretical study of the problem of multicomponent adsorption−desorption in sorbent particles under pressure swing conditions is carried out in this study. A rigorous mathematical model is formulated for the process in which the dusty-gas model and the commonly used Fickian model are employed to describe the coupling of the mass fluxes and the partial pressures in the pore space, with or without viscous flow. The dusty-gas model is used as a standard against which the performance of the Fickian model is tested. Computations are carried out for binary and quaternary mixtures. It is found that the rigorous model (the one based on the dusty-gas model) predicts faster responses for the partial pressures of the components in the mixture. Faster responses are also observed when the viscous flow is accounted for in the transport model, with the effect being considerably stronger in the case of the Fickian model. The obtained results are also used to investigate the performance of the Glueckauf linear driving force approximation for multicomponent systems. It is concluded that like the Fickian diffusion model on which it is based, this approximation cannot predict, even qualitatively, the dynamic responses of the partial pressures in a multicomponent system.

This paper summarises the results of an international survey of academics and industrialists on what should be prioritised in the first, and often only, control course taken by engineering undergraduates. The results are made up both of quantitative data whereby respondents selected from a number of options, and also of qualitative data where respondents entered free comments. Reflections on the results and summaries of common trends are given to help readers consider how the curriculum in their own institutions might be updated and modified to meet modern requirements. At the time of writing the survey had around 500 respondents covering a good spread of nationalities, employment status and engineering disciplines.