Photocatalytic degradation of bisphenol A using Ti-substituted hydroxyapatite

Abstract

Ti-substituted hydroxyapatite (TiHAP) is a new photocatalyst with high adsorption capacity and photocatalytic activity. The morphology and structure of TiHAP were characterized using transmission electron microscopy, X-ray diffraction, ultraviolet-visible spectrophotometry, and the zeta potential. The adsorption and photocatalytic degradation of bisphenol A (BPA, an environmental endocrine disrupting chemical) over TiHAP and P25 TiO 2 photocatalysts were studied using liquid chromatography-mass spectrometry. The influences of fulvic acid and Fe 3+ ions on the BPA degradtion rate were analyzed. The adsorption of BPA on TiHAP and TiO 2 obeyed the Langmuir adsorption equation. TiHAP exhibited much higher adsorption capacity and photocatalytic degradation activity of BPA than TiO 2 . Fulvic acid and Fe 3+ showed different effects on the photocatalytic activity of TiHAP and TiO 2 films. These were explained by band structure theory, the electron transfer path, and optical absorption capacity. The results are useful for the application of TiHAP in the photocatalytic degradation of environmental endocrine disrupting chemicals. TiHAP film showed an enhanced photocatalytic activity than P25 TiO 2 film for degradation of bisphenol (BPA), an important kind of environmental endocrine disrupting chemicals.