Adsorption-Desorption, And Kinetic Study Of Diazinon By Batch Equilibrium

Abstract

Adsorption of organic compounds in the soil is a crucial process in terms of pesticide effectiveness. Adsorption of pesticides can lead to decreasing of its toxic effect against various pests, and finally fail the pests targeted control. This study was performed to assess the diazinon adsorption-desorption kinetic behaviour in the soil. The results revealed that diazinon is subjected to soil sorption. The kinetic reaction of diazinon underwent the pseudo-second order reaction, achieving a rate constant from 0.00056 to 0.003565 hour-1. This reaction revealed that diazinon behaviour is influenced by two factors in the soil. The equilibrium of diazinon was achieved after 2-6 hours in soil, providing an important sight on diazinon behaviour. Where the diazinon concentrations decreased gradually to reach 5.95 mg mL-1. The adsorption isotherm showed that diazinon is a best fit to the Langmuir model, which ranged from 0.798 to 1.062 μg mL-1 rather than the Freundlich model that was between 2.102 to 2.687. These findings of this study have a number of important implications for the future, not only water-soil pollution, but also pests control.