The perovskite-ty pe LaFe 0.9Co0.1O3 (LFCO1) and LaFe 0.1Co0.9O3 (LFCO2) nanoparticles (NPs) were prepared via sol–gel method. The structure and morphology of NPs were characterized by thermogravimetric analysis (TGA), X-ray diffraction (XRD), infrared spectroscopy (FT-IR), scanning electron microscopy (SEM),scanning tunneling microscopy (STM), energy dispersive X-ray spectroscopy (EDX), and Brunauer–Emmett–Teller (BET). The average particle size of NPs is approximately between 20 and 40 nm. The ability of calcined NPs to remove vitavax as a typical pesticide in aqueous solutions was assessed. The removal kinetic studies were conducted on LFCOs NPs with different contact time, temperatures, initia pesticide concentrations, and adsorbent doses to find the optimum conditions. The results showed both NPs can rem ove the vitavax from aqueous solution with a very high adsorption capacity. The removal proce ss follows first-order kinetics and the Langmuir adsorption isotherm model. The activati on energy and Arrhenius factor were obtained from temperature dependence of the rate constant. The thermodynamic parameters of the adsorption were also determined.

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