Sorption, kinetics and thermodynamics studies of atrazine herbicide removal from water using iron nano-composite material

Atrazine organic pollutant has been found in several water resources of the world. It is highly toxic and carcinogenic in nature. Atrazine is removed by adsorption on iron composite nanoparticles. The composite nanoparticles were synthesized, analyzed and applied for atrazine uptake from water. Residual atrazine was monitored by gas chromatography-mass spectrometry. The maximum atrazine removal (95 %) was achieved using contact time 30.0 min, concentration 30.0 A mu g/L, pH 7.0, dose 2.5 g/L and temperature 20.0 A degrees C. The adsorbent was selective for atrazine adsorption. The results obeyed Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherms. Delta GA degrees values were -6.05, -6.11 and -6.15 kJ/mol at 20, 25 and 30 A degrees C temperatures, respectively. The value of Delta SA degrees was -2.45 x 10(-3) kJ/mol K. It showed decline in entropy of atrazine uptake. The adsorption followed pseudo-second-order kinetics. The adsorption mechanism was liquid film diffusion. The proposed adsorption method is inexpensive, fast and reproducible. It can be used to remove atrazine from any water sample/source.