β-Cyclodextrin-enhanced photodegradation of bis(4-hydroxyphenyl)ethane under UV irradiation

✍ Scribed by Guanghui Wang; Xiaofei Xue; Haifeng Li; Feng Wu; Nansheng Deng

• Publisher: Elsevier Science
• Year: 2007
• Tongue: English
• Weight: 701 KB
• Volume: 276
• Category: Article
• ISSN: 1381-1169
• DOI: 10.1016/j.molcata.2007.06.024

✦ Synopsis

␤-Cyclodextrin (␤-CD) reacts with bis(4-hydroxyphenyl)ethane (BPE) forming a 1:1 inclusion complex, the formation constant of which is 7.81 × 10 3 l mol -1 . In the present study, the enhanced photodegradation behavior of BPE in the presence of ␤-CD was investigated under a 30 W UV lamp (λ max = 254 nm). As a result, the photodegradation rate constant of BPE in aqueous solution with ␤-CD showed a 5.37-fold increase. After 60 min UV irradiation, addition of ␤-CD increased the photodegradation efficiency of 10.0 mg l -1 BPE by about 54.4%, simultaneously enhancing the mineralization of BPE. The effect of ␤-CD concentration, the presence/absence of organic solvent and pH on the photodegradation of BPE were also studied. The predominant photodegradation products were p-hydroxybenzoic acid, m-hydroxylated BPE and o-hydroxylated BPE. The enhancement of photodegradation of BPE was mainly shown to be the result of an increase in the frontier electron density of BPE after inclusion of ␤-CD and the moderate inclusion depth of BPE molecules in the ␤-CD cavity.