Study of 2,4-D herbicide removal from aqueous solutions using synthesized TiO2-zeolite nanocomposite by laser irradiation.

TiO₂/Zeolite composite was synthesized through a sol-gel approach continuously. TiO₂/Zeolite composite was exposed to laser irradiation until conversion to TiO₂/Zeolite nanocomposite (T/Z) and T/Z was modified with m-phenylenediamine (N-T/Z). The resulting N-T/Z was characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray, dynamic light scattering, and thermogravimetric analysis. The average range of particle size of the N-T/Z was about ~140 nm. The N-T/Z product was evaluated as a sorbent for removing 2,4-D from aqueous solutions. The adsorption operational parameters were investigated in a batch system. The complete removal of 2,4-D was investigated under optimum conditions in real samples by high-performance liquid chromatography. A 2,4-D removal efficiency of 72%-99% was obtained from the river, well, and agricultural drainage water samples. The pseudo-second-order kinetic model fitted the 2,4-D removal, and equilibrium data well followed the Langmuir model. The maximum adsorption capacity of the obtained sorbent was q_max = 4.914 mg g^-1. The product had excellent stability for reprocessing in several runs without losing adsorptivity significantly. [ABSTRACT FROM AUTHOR]