MODELING AND SIMULATION OF CARBON MASK ADSORPTIVE REACTORS

A carbon gas mask is considered in this paper for the elimination of C NCl by adsorption in the activated carbon support-and simultaneous sec ond order chemical reaction with the impregnant metal. A model, taking into account nonlinear adsorption, chemical reaction, film and intrap article mass transfer resistances, and axial dispersion is written and solved by the moving finite elements method. In the very short beds u sed in carbon gas masks, axial dispersion is probably important. Simul ations are carried out for different values of the parameters in order to assess the influence of the intraparticle and film mass transfer r esistances and of the rate of reaction on the system behavior in the p resence of axial dispersion. It is shown that, although axial dispersi on does not alter the general behavior of the system, its presence can reduce dramatically the usefulness of these respirators. On the other hand, two different-correlations give more than 1 order of magnitude differences in the value of axial dispersion to be expected in the bed .