Removal of paraquat from aqueous solutions onto zeolite LTL

Abstract

Zeolite LTL (K_LTL and H_LTL) was used as adsorbent for the adsorption of herbicide paraquat from an aqueous solution. The characterization of zeolite LTL has been carried out through various techniques: X-ray diffraction, X-ray fluorescence spectroscopy, Fourier transform infrared spectroscopy and surface analysis. The adsorption occurred through cation exchange and the results showed that the adsorption capacity of paraquat onto K_LTL (161.71 mg/g) is higher than H_LTL (25.67 mg/g). These results can be explained by the amount of Al in the structure of zeolite and affinities of negative sites in zeolite and extra-framework cations (K+ and H+). The equilibrium data was best adjusted using the Langmuir model which has high correlation coefficient values (0.99).