Adsorption of diazinon using Cd-MOF nanoparticles before determination by UV-Vis spectrometer: isotherm, kinetic and thermodynamic study

In this work, cadmium metal–organic frameworks (Cd-MOF) has been prepared using a hydrothermal method and characterized by the SEM, elemental mapping, XRD, EDS, and BET analysis. The diazinon stability has been investigated in various pH (4-8) and temperature (298°K – 323°K) using UV-Vis spectrometer in the range of 230 – 280 nm, at its main absorption peak at 247 nm. Adsorption behaviors of diazinon on the Cd MOF were considered in different conditions. UV Vis spectroscopy was used to monitor the removal of diazinon using the Cd MOF. The adsorption capacity of 138 mg g^-1 was obtained. The effect of temperature (298°K -323°K), pH (4-8), adsorbent dose (1-7 mg), initial concentration (4-12 mg L^-1), stirring speed (0-500 rpm), and adsorption kinetics were studied using batch rout. All the studied parameters have shown significant effects on the efficiency of removal of diazinon by the Cd MOF. The adsorption thermodynamic was investigated in the temperature range of 298°K to 323°K and it has shown the endothermic nature of adsorption of diazinon using prepared Cd MOF. The adsorption isotherm follows by the Langmuir isotherm model. It was demonstrated that synthesized adsorbent could be effectively used for the removal of diazinon from water.