Comparison of the surface features of two wood-based activated carbons

The surface features of two carbons of wood origin were compared. One sampl e was manufactured using phosphoric acid activation and the other using pot assium hydroxide activation. To check the susceptibility to oxidation and t he stability of the porous structure, the samples were oxidized with ammoni um persulfate. Structural properties of carbons and their oxidized counterp arts were determined using sorption of nitrogen. Surface acidity was evalua ted using Boehm titration, potentiometric titration, inverse gas chromatogr aphy, and diffuse reflectance FTIR. It was demonstrated that, despite the s ame wood origin, the carbons significantly differ in their pore structure a nd surface chemistry. The carbon obtained using KOH activation is homogeneo usly microporous with high surface area around 2300 m(2)/g (BET). On the ot her hand, the carbon manufactured using phosphoric acid contains a high vol ume of mesopores and its surface area is significantly lower. The carbons a lso differ in their surface chemistry and susceptibility to oxidation.