UiO-66 (Zr-MOF): Synthesis, Characterization, and Application for the Removal of Malathion and 2, 4-D from Aqueous Solution

UiO-66 (Zr-MOF) metal-organic framework was successfully synthesized by the solvothermal method and characterized using FTIR, PXRD and TGA. Its ability to remove Malathion, 2,4-Dichlorophenoxyacetic acid (2,4-D) and a mixture of the two from an aqueous solution was studied. Effects of different experimental parameters (pH, adsorbent dose, contact time, speed of agitation and initial pesticide concentrations) were studied. Adsorption isotherm study revealed that the equilibrium data well fitted the Freundlich, Langmuir and Jovanovic isotherm models. Similarly, the kinetics study showed that the pseudo-first-order model gave the best fitting. Thermodynamic study indicated that the adsorption process was spontaneous and exothermic. To evaluate the matrix effect, tap water samples were spiked with standard solutions of the analytes and recoveries in the range of 70–120% were obtained. Based on the findings of the present study, UiO-66 (Zr-MOF) could be taken as a promising adsorbent for the removal of pesticides from aqueous samples