SORPTION OF PHENOL AND PARA-CHLOROPHENOL FROM WATER USING CONVENTIONAL AND NOVEL ACTIVATED CARBONS

A comparative study of the sorption of phenol and p-chlorophenol from water has been performed using novel samples prepared by carbonisation and subsequent activation of straw and used rubber tyres as well as conventional activated carbons based on coal, coconut shell and wood. Pseudo-equilibrium sorption of phenol and p-chlorophenol obeys a Freundlich type adsorption isotherm of the form; q = k c(n) in the adsorbate concentration range 0-6 mmol l(-1). Measured values of k and n indicate that the sorption of phenol and p-chlorophenol onto active carbons derived from straw and used rubber tyres is almost identical to that for conventional activated carbons. The rate of adsorbate uptake has been measured and the sorption half-times lie in the range 1.4-15 min for phenol. The sorption kinetics of the straw and rubber tyre based carbons are likewise identical to conventional carbons based on coal and wood but appreciably faster than the coconut shell sample selected for comparison.