β-CD effect on 2,4-D soil adsorption

The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) and the β-Cyclodextrin (β-CD) interact to obtain an inclusion compound in solution and in solid state. The effect of the presence of β-CD on the adsorption-desorption behaviour of the pesticide 2,4-D on soil has been studied by batch equilibration experiments. The removal of 2,4-D previously absorbed on soil has been improved using β-CD solutions, due to the enhancement of 2,4-D solubility as a consequence of formation of water soluble 1:1 inclusion compounds 2,4-D-β-CD. The high complexing capacity of β-CD towards 2,4-D has been demonstrated. On the contrary, the treatment of the soil with β-CD solution before 2,4-D application increases the adsorption capacity of the soil.