Abstract

In this study, 2,4,6-trichlorophenol (TCP) was removed from aqueous solutions by clinoptilolite-rich tuff modified with cetylpyridinium bromide (CPB). CPB modification significantly increased the TCP adsorption capacity, so that the highest adsorption capacities of the natural zeolite and cetylpyridinium bromide-modified zeolite (CPB-MZ) at the same experimental conditions were determined to be 1.6 and 8.5 mg/g, respectively. Kinetic and isotherm of TCP adsorption were studied in a batch system in which kinetic experiments revealed that the TCP adsorption by the CPB-MZ reached to equilibrium in 45 min for all TCP concentrations. The kinetic of TCP adsorption onto the CPB-MZ was best described by the pseudo-second-order equation (R-2 > 0.99) while the isotherm data were best fitted with the Langmuir model (R-2 > 0.99). The continuous adsorption experiments were performed in a packed bed column. The maximum adsorption capacity (q(m)) of TCP was 16.34 mg/g according to the Langmuir model. In this system, by increasing the influent TCP concentration from 100 to 200 mg/L, the adsorption capacity increased from 19.35 to 40.78 mg/g at complete exhaustion point.