Degradation of triphenylborane-pyridine antifouling agent in water by copper ions

作者:Tsuboi, Ai; Okamura, Hideo*; Kaewchuay, Netnapit; Fukushi, Keiichi; Zhou, Xiaojian; Nishida, Tomoaki
来源:Environmental Technology, 2013, 34(20): 2839-2844.
DOI:10.1080/09593330.2013.790083

摘要

Triphenylborane-pyridine (TPBP) is an antifouling compound used in Asian countries, including Japan, and its residue has not been detected in aquatic environments to date. There are limited data on its fate for environmental management. The purpose of this study was to evaluate whether TPBP is degraded by metal ions in aquatic environments. TPBP with metal ions in 20mM sodium acetate buffer at pH 8.0 was placed at 25 degrees C in the dark for 24h. The concentrations of TPBP and its degradation products, such as diphenylboronic acid, phenylboronic acid (MPB), phenol, benzene, biphenyl, and boron were determined. The presence of copper ions (50mg/l), but not zinc or manganese ions, resulted in complete degradation of TPBP in 24h. The TPBP degradation was much faster than the boron production in the initial reaction (0-1h) with copper salts, depending on the copper salts tested. TPBP was degraded by copper ions (5mg/l) in 24h, producing phenol, MPB, biphenyl, and borate. Cu2+ as copper(II) chloride or copper(II) acetate led to complete degradation of TPBP, and ethylenediaminetetraacetic acid disodium salt addition suppressed the TPBP degradation. Cu+ as copper(I) acetate also completely degraded TPBP, and bathocuproine addition suppressed the TPBP degradation. This suggests that copper ions existing in natural environments might degrade TPBP released from antifouling paint into water, and this could be one of the important mechanisms to dissipate TPBP residues in aquatic environments.