Synthesis and characterization of polyaniline Zr(IV) molybdophosphate for the adsorption of phenol from aqueous solution

In the present investigation, a composite cation exchange material has been synthesized by the sol-gel method and used as an adsorbent for the removal of phenol from aqueous solutions. Scanning electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction and transmission electron microscopy studies were performed to characterize the polyaniline Zr(IV) molybdophosphate (PZMP) particles. The average size of the PZMP was in the nano-range. Batch adsorption studies were carried out to study the effect of various parameters like effect of pH, initial concentration, contact time and temperature. Increase in the initial phenol concentration with time could effectively increase the phenol adsorption capacity. Adsorption data of phenol agreed well with Langmuir, Freundlich, Temkin and Dubinin-Redushkeuich (D-R) isotherms at different temperatures. The maximum phenol adsorption capacity was obtained as 25.144 mg/g for 50 mg/L initial phenol concentrations. Thermodynamic parameters showed that adsorption of phenol were endothermic, spontaneous and thermodynamically favorable. The kinetic data followed pseudo-second order kinetic model.