pH of activated carbon surface as an indication of its suitability for H2Sremoval from moist air streams

Samples of activated carbons of different origins were tested as removers o f hydrogen sulfide at room temperature. The breakthrough capacity was evalu ated using a lab designed test. The surface properties of the carbons were studied using Boehm titration, nitrogen sorption and thermal analysis. The results obtained indicate that the choice of unimpregnated carbon for hydro gen sulfide removal should be based on the parameters describing surface ac idity such as pH, number of acidic groups, or weight loss during thermal tr eatment associated with the presence of acidic functional groups. There are certain threshold ranges of these quantities which, when exceeded, have a dramatic effect on the H2S breakthrough capacity. (C) 2001 Elsevier Science Ltd. All rights reserved.