Etude d'adsorption du phénol, du 4-chlorophénol et du 4-nitrophénol sur deux charbons actifs préparés à partir des tourteaux de karité (CA-K) et des graines de coton (CA-C): étude cinétique.

Activated carbons prepared from Shea cake (CA-K) and cotton cake (CA-C) were investigated for removal of phenol and some derivatives. The two activated carbons were prepared by chemical activation using phosphoric acid as activation agent. Chemical characteristics of these activated carbons was monitored by Bohem titration and the method of Lopez-Ramon et al. while surface areas of the samples were determined by nitrogen adsorption/desorption isotherm measurement. The removal of phenolic compound was studied using batch reactor. Activated carbons CA-K and CA-C have the following characteristics: BET surface and the pore volumes are respectively 1148 m2/g and 0.607 cm3/g for CA-K, 584 m2/g and 0.298 cm3/g for CA-C. The two activated carbons are microporous activated carbon with micropores volume representing more than 70% of the total pore volume. The nature of the activated carbon and the pollutants are the key factors influencing the contact time. The study of adsorption isotherms showed that the adsorption of phenolic compound is well described by the kinetic models of Langmuir and Freundlich. According to the maximum adsorption capacities between 17.8 mg / g and 26.9 mg / g, the activated carbons CA-K and CA-C can be used for the removal of phenolic compounds from water. [ABSTRACT FROM AUTHOR]