Adsorption and Leaching Potential of Imidacloprid Pesticide through Alluvial Soil

Abstract

This study was aimed to assess the adsorption and leaching potential of imidacloprid pesticide in column and field soil. To understand mechanism of adsorption and factors affecting, the experiments were carried out under laboratory and field conditions. Adsorption study was divided into kinetic and equilibrium sections. The evaluation of kinetic data was done through pseudo first and second order models. It was found that kinetic adsorption of imidacloprid on soil followed pseudo second order with rate constant value of 4.333 mg/g/h. Langmuir and Freundlich isotherms were used to explain equilibrium adsorption, from these isotherms it was evaluated that Freundlich isotherm was obeyed well with adsorption capacity of 2.190 -4.573 mol/g. Leaching study was performed in laboratory using column made of polyvinyl chloride having 30 cm length. Known amount of imidacloprid pesticide was applied to column left for adsorption and then eluted with 500 mL water in five equal portions. These water portions and soil of column which was divided into three sections were analyzed by HPLC. The result revealed that the concentration of imidacloprid was decreased from 0.481 ppm in first portion of water to 0.327 ppm in last portion of water while 0.783 ppm in first section of column soil to 0.038 ppm in last section of column soil. In field the leaching power of imidacloprid was observed up to 60 cm depth, its concentration decreased with soil depth. It was 3.311 ppm in first portion of soil and 0.357 ppm in last portion of soil. The leaching potential of imidacloprid pesticide up to 60 cm soil depth was due to less organic matter, sandy texture, alkaline pH, and low cation exchange capacity.

Time and temperature dependent sorption behaviour of dimethoate pesticide in various Indian soils

“…This indicates that the adsorption was a complex process and several mechanisms were involved ( Peng et al, 2012). Moreover, in the chemisorption process, the pseudo second order is superior to the pseudo-first order model because it deals with interaction of adsorbent-adsorbate through their valency forces (Bajeer et al, 2012). Therefore, the rate-limiting step may be chemical adsorption.…”

“…Therefore, the adsorption data can be explained better using the Freundlich model at all the temperatures. This model is related to the non-ideal, reversible, and multilayer adsorption with non-uniform distribution of adsorption heat and affinities over the heterogeneous surface (Bajeer et al, 2012).…”

Aspect of the degradation and adsorption kinetics of atrazine and metolachlor in andisol soil

“…Next, the experimental data were tested using the Freundlich equation which is related to nonideal, reversible, and multilayer adsorption with non-uniform distribution of adsorption heat and affi nities over the heterogeneous surface (Bajeer et al, 2012). The equation was used in its log-transformed form (Eqn.…”

Spinosad Adsorption on Humic and Clay Constituents of Lacustrine Egyptian Soils and Its Leaching Potential

“…This finding is consistent with Hui-jun et al (2013) on of spinosad. On the other hand, Bajeer et al (2012) reported that the equilibrium time for imidacloprid obtained in alluvial soil was reached after 6 h. It was found that the time required for a pesticide-soil system to reach adsorption equilibrium depends on the type of pesticide and soil characteristics (Nkedi-kizza and Brown, 1998).…”

“…Polluted soil, surface and ground waters involve risk to the environment and also to human health due to possible direct or indirect exposures. (Bajeer et al, 2012).…”