Poly(2-chloroaniline) (P2ClAn) /pumice (Pmc) and poly(o-toluidine) (POT)/Pmc composites were synthesized via the chemical oxidative polymerization of 2-chloroaniline and o-toluidine in the presence of a dispersion of Pmc powders in water solvent with an (NH4)(2)S2O8 oxidant. The composites were characterized with Fourier transform infrared (FTIR) spectroscopy, thermo-gravimetric /differential thermal analysis (TG-DTA), and scanning electron microscopy devices. The presence of P2ClAn and POT in the structure of the composites was confirmed by FTIR. The results of analysis show strong interactions between the homopolymers and Pmc. The applicability of the P2ClAn/ Pmc and POT/Pmc composites were investigated for the removal of Cr(VI) ions in water. Batch adsorption experiments were carried out as a function of pH, initial concentration, time, adsorbent dosage, and temperature. The batch sorption kinetics were tested, and the applicability of the Langmuir and Freundlich adsorption isotherms for this system was tested at 20 +/- 1 degrees C. An initial pH of 3.0 was most favorable for Cr(VI) removal by all adsorbents. The adsorption capacities obtained were 0.187 and 4.959 mmol/g of adsorbent for POT/Pmc and P2ClAn/Pmc from the Freundlich and Langmuir adsorption isotherms, respectively. (c) 2007 Wiley Periodicals, Inc.