Removal of contaminated compound in soil by inclusion of modified cyclodextrin

Contamination of soil by PCB and dioxin is a serious pollution problem. The compounds have high affinity with soil, so that effective removal of the c ompounds from the soil is an important technical problem. The aim of this s tudy is the development of the removal process of the contaminated compound s from soil by including the compound selectively in the cavity of cyclodex trin. In this work, to obtain fundamental knowledge for the remediation of soil by means of cyclodextrin, biphenyl was used as a model contaminated co mpound. We carried out fundamental studies such as enhancement of the solub ility of biphenyl by cyclodextrin, the desorption of biphenyl from the soil by kneading the mixture of the contaminated soil and cyclodextrins using a twin-screw kneader, and biodegradation of the biphenyl included in an aero bic system by activated sludge. Among various cyclodextrins, hydroxypropyl- beta -cyclodextrin (HP-beta -CD) shows the highest enhancement of the solub ility of biphenyl. Desorption of biphenyl from the contaminated soil is the most effective in the case of using HP-beta -CD by means of a twin-screw k neader.