Removing atrazine herbicide from water with an efficient metal–organic framework

Abstract

Metal–organic framework (MOF) synthesis has been studied for over 50 years, yet its use in adsorbing herbicides is still under investigation. This study examined the effects of amino‐MIL‐101(Fe) on the adsorption and removal of atrazine (AZ). The novel amino‐MIL‐101(Fe) nanoadsorbent has been completely characterized after and before the adsorption process using Fourier‐transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM), X‐ray diffraction (XRD), energy‐dispersive X‐ray photoelectron spectroscopy (XPS), and nitrogen adsorption–desorption isotherm. The Brunauer–Emmett–Teller (BET) surface area of the novel amino‐MIL‐101(Fe) nanoadsorbent before and after five‐time reuse were 1222 and 1038 m2/g, respectively. The amino‐MIL‐101(Fe) nanoadsorbent was found to have the greatest adsorption capacity (qmax) of 321.55 mg/g. Variables such as herbicide concentration, pH, adsorbent dosage, and temperature that affect the adsorption process have been investigated. It was found that the ideal conditions for high adsorption capacity were pH 4 and a dose of 0.02 g. The adsorption isotherm and the kinetic isotherm were fitted to the Langmuir equation and the pseudo‐second‐order equation, respectively. The chemisorption mechanism was identified as the driving force. According to adsorption thermodynamics, the adsorption process was spontaneous and endothermic. The quantities of AZ adsorbed grew along with the temperature. The amino‐MIL‐101(Fe) nanoadsorbent can be reused up to five times with no change in its chemical composition and identical results from XRD before and after reuse. The mechanism of interaction by which the amino‐MIL‐101(Fe) interacted with the AZ has been represented.