Abstract

Cyclodextrins (CDs) were successfully used to extract numerous commonly used pesticides from contaminated soil via cyclodextrin complexation, a more environmentally friendly method compared to surfactants and organic solvents. A combination of five CDs (α-CD, β-CD, γ-CD, hydroxypropyl-β-CD (HP-β-CD), and methylated-β-CD (M-β-CD)) and eight pesticides (2,4-Dichlorophenoxyacetic acid (2,4-D) alachlor, acetochlor, diazinon, dicamba, dimethanamid, metalochlor and propanil) were examined in this study. It was found that a linear relationship exists between the concentrations of the M-β-CD and alachlor, which generally indicates that the amount of pesticide extracted depends on the concentration of the cyclodextrin present. With some pesticide-cyclodextrin combination, it was found that as the concentration of cyclodextrin increases the CD-pesticide inclusion complex precipitated out of solution, thus reducing the solubility of the pesticide. Overall the most effective extractants based on this study were found to be HP-β-CD and M-β-CD.