A comparative study of adsorption and removal of organophosphorus insecticides from aqueous solution by Zr-based MOFs

The adsorptive removal of hazardous materials of organophosphorus insecticides by adsorbents with high adsorption capacities is highly desirable. In this work, we present the removal of two representative organophosphorus insecticides, Dichlorvos and Metrifonate by two exceptionally stable Zr-based MOFs of UIO-66 and UIO-67. The MOFs were characterized by TGA, FTIR, SEM, XRD, BET and XPS analyses. Effect of some parameters such as adsorbent dose, contact time, pH and ionic strength on the removal efficiency of Dichlorvos and Metrifonate were investigated. The mechanism of interaction was carefully investigated by XPS and FTIR. The isotherm and kinetic data were accurately described by the Langmuir and pseudo-second-order models. The adsorption capacities in UIO-67 approached as high as 571.43mgg−1 for Dichlorvos and 378.78mgg−1 for Metrifonate, which were much higher than UIO-66. Compared to other works this work has shown better adsorption capacity and cost efficient. The calculated removals for the samples are in the range from 97.8 to 99%, indicating that the UIO-67 can be applied for removal of Dichlorvos and Metrifonate in real samples.