ADSORPTION-ISOTHERMS OF PHENOLIC-COMPOUNDS FROM AQUEOUS-SOLUTIONS ONTO ACTIVATED CARBON-FIBERS

Liquid-phase adsorption equilibria of eight phenolic compounds onto ac tivated carbon fibers were measured in the concentration range 40-500 g . m(-3) at 303 K. High adsorption capacities were observed for the c hlorinated phenols compared to the methyl-substituted phenols. Several two- and three-parameter isotherm equations were tested. Among the eq uations tried, the three-parameter equation of Jossens et al. based on a heterogeneous surface adsorption theory was found to be the most sa tisfactory over the entire range of concentration. The widely used two -parameter equations of Langmuir and Freundlich were not applicable to the present adsorption systems.