Effect of Organic Solvent (Methanol) on the Adsorption and Movement of Carbofuran on Three Soils of Divergent Texture

Adsorption and movement of carbofuran in three different types (loam, silt clay loam, sandy loam) of soils in methanol-water mixtures at various ‘f_s’ values has been studied by using batch shake and soil TLC technique, respectively. Higher adsorption and lower movement of carbofuran was observed in loam soil followed by silt clay loam and sandy loam soils. This was corroborated with Freundlich constants Kand Sm values. The K_mand S_m values also confirm that carbofuran adsorption decreased while the movement of carbofuran increased with increase in ‘f_s’ values. The Freundlich adsorption constant (K_m) was used to evaluate the cosolvent theorj for describing adsorption of carbofuran in methanol-water mixtures. The aqueous phase partition coefficient K_w (mol gol) normalized on f_oc for carbofuran was evaluated by extrapolating f_s = O.