PREPARATION OF ACTIVATED CARBON FROM A CA RBONIZED PRODUCT OBTAINED FROM ROCKROSE EXTRACTED INTO PETROLEUM ETHER - INFLUENCE OF DE ACTIVATING AGENT AND THE ACTIVATION METHOD

The preparation of activated carbon from rockrose (Cistus ladaniferus, L.) was studied. The material was first extracted into petroleum ethe r and then carbonized at 600 degrees C. Activations of the char (X600; 0,32 < phi 1,00 mm) were conducted ir air at 450 degrees C and in CO2 or steam at 900 degrees C. The heat treatments of X600 were always ef fected until burn-off 40% either in the atmosphere of an only activati ng agent or successively in the atmospheres of two gasifying agents, t he partial burn-off percentages in this case being 20%. Techniques use d in the characterization of the different products were gas adsorptio n, density measurements and FT-IR. Air activation was slower and scarc ely affected the textural properties of the carbonized product. CO2 or steam activations resulted. in activated carbons with similar textura l characteristics. Steam activation was faster. The development of por osity in the activated carbons was higher than in the carbonaceous pre cursor. The successive activations with CO2 and steam gave rise to the activated carbon with the best textural properties. The FT-IR spectra of activated products suggests the presence in the materials of surfa ce olefinic C=C double bonds, aromatic rings, and oxygen functional gr oups.