Unlike activated charcoals, which are porous, graphitized carbon blacks (GCBs) are generally non-porous. Consequently, the entire surface of these materials is available for interactions that depend solely on dispersion (London) forces. Carbotrap™ signifies material that is 20/40-mesh size, whereas Carbopack™ signifies material that is smaller than this mesh. Unlike most GCBs, Carbopack™ X is porous. Its surface area of 240m2/g provides greater adsorption strength than other GCBs; hence it is a unique bridge between GCBs and carbon molecular sieves. Carbopack™ Y, with a surface area of 24m2/g, bridges the characteristics of Carbopack™ B and Carbopack™ C.