Photodegradation of diethyl phthalate with PANi/CNT/TiO2 immobilized on glass plate irradiated with visible light and simulated sunlight-effect of synthesized method and pH

Chung-Hsuang Hung; Ching Yuan; Huei-Wen Li

doi:10.1016/j.jhazmat.2016.01.073

Photodegradation of diethyl phthalate with PANi/CNT/TiO₂ immobilized on glass plate irradiated with visible light and simulated sunlight-effect of synthesized method and pH

J Hazard Mater. 2017 Jan 15;322(Pt A):243-253. doi: 10.1016/j.jhazmat.2016.01.073. Epub 2016 Feb 4.

Authors

Chung-Hsuang Hung¹, Ching Yuan², Huei-Wen Li³

Affiliations

¹ Department of Safety, Health and Environmental Engineering, National Kaohsiung First University of Science and Technology, No. 1, University Rd., Yenchau Dist., Kaohsiung 824, Taiwan. Electronic address: jeremyh@ccms.nkfust.edu.tw.
² Department of Civil and Environmental Engineering, National University of Kaohsiung, No. 700, Kaohsiung University Rd., Nan-Tzu Dist., Kaohsiung City 811, Taiwan. Electronic address: caroline@nuk.edu.tw.
³ Department of Civil and Environmental Engineering, National University of Kaohsiung, No. 700, Kaohsiung University Rd., Nan-Tzu Dist., Kaohsiung City 811, Taiwan. Electronic address: soillab@nuk.edu.tw.

PMID: 26880217
DOI: 10.1016/j.jhazmat.2016.01.073

Abstract

Diethyl phthalate (DEP) is one of the most common phthalates for industrial use and has widely spread in environment. A series of PANi/CNT/TiO₂ potocatalysts immobilized on glass plate irradiated with visible light were presented to degrade DEP in this study. The PANi/CNT/TiO₂ potocatalysts were fabricated by co-doping with polyaniline (PANi) and two functionalized CNT (CNT-COCl and CNT-COOH) onto TiO₂ followed by a hydrothermal synthesis and a sol-gel hydrolysis. Doping of PANi resulted in the absorption edge of the fabricated potocatalysts shifting to 421-437nm and the most distinguished red-shift effect was found in hydrothermal synthesized photocatalysts. The best DEP degradation of 41.5-59.0% and 44.5-67.4% was found in the simulated sunlight system irradiated for 120min for sol-gel hydrolysis PANi/CNT/TiO₂ photocatalysts and hydrothermal synthesized ones, respectively. The optimum pH was determined at 5.0 and 7.0 for the two PANi/CNT/TiO₂ photocatalysts mentioned above, respectively. The reusability of the sol-gel hydrolyzed photocatalysts up to 5 times was observed no decline in the photodegradation efficiency but less photocatalytic stability of the hydrothermal synthesized ones was found. Meanwhile, the active species of OH radicals generated in the DEP degradation system was identified by free radical scavenging experiments.

Keywords: Diethyl phthalate; Immobilization; PANi/CNT/TiO(2); Recyclability tests; Solar photocatalysis.