Effect of pore structure and surface chemistry of virgin activated carbonson removal of hydrogen sulfide

Three activated carbons of various origins were tested as H2S adsorbents, c hosen to differ significantly in surface area, pore structure and surface c hemistry. The carbons were characterized by sorption of nitrogen and water vapor, potentiometric titration, Boehm titration, and thermal analysis. The results showed that a heterogeneous carbon (having micro- and mesopores) w ith chemical surface functionality performs better than apparently neutral, predominantly microporous materials with high surface areas. This is thoug ht to be due to the adsorption of water on surface groups which enhances th e oxidation of H2S to sulfur or ultimately to sulfuric acid. (C) 1999 Elsev ier Science Ltd. All rights reserved.