ASSESSMENT OF ACTIVATED CARBON STABILITY TOWARD ADSORBED ORGANICS

Activated carbon adsorption technology is an important industrial process used in solvent recovery and air pollution abatement systems. The safe use of activated carbon requires an understanding of the conditions that might promote carbon bed exotherms. A test method has been developed which evaluates the relative oxidative activity characteristics of carbons containing organic molecules and their relative potentials for resulting in carbon bed exotherms. Results indicated that the degree of oxidizability of adsorbed organic molecule plays an important role. However, various carbons exhibited different levels of oxidative behavior toward adsorbed oxidizable organic solvents. The solvent reaction initiation temperature for methyl ethyl ketone oxidation on the carbons investigated ranged from 239 to 383 K. Observed reaction enthalpies indicated a difference of more than a factor of 5 between the least reactive and most reactive carbons. This test method predicts trends in carbon and solvent reactivities similar to those determined from column studies reported in the literature.