REMOVAL OF PHTHALIC-ACID ESTERS FROM AQUEOUS-SOLUTION BY INCLUSION AND ADSORPTION ON BETA-CYCLODEXTRIN

Removal of phthalic acid esters (PAEs) by the formation of inclusion c omplexes with beta-cyclodextrin (beta-CD) in aqueous solution was stud ied. According to the measurements of fluorescence and NMR spectroscop y, it was confirmed that PAEs were included into the beta-CD cavity. T he stability constants of the beta-CDPAE complexes were varied dependi ng on the alkyl chain length of the PAEs. The adsorption isotherms of PAEs and beta-CD polymer (beta-CDP) were well described by Freundlich isotherm equations, and the adsorption capacity varied according to th e stability constant. PAEs were well adsorbed by beta-CDP both in batc h and in a column system, and the PAEs were also released from beta-CD P by shaking with a mixture of methanol and water. The recovery effici ency was varied with the mixture ratio of methanol and water, and the recovered beta-CDP was reusable as an adsorbent.