Preparation and characterization of a copper phosphotungstate/titanium dioxide (Cu-H3PW12O40/TiO2) composite and the photocatalytic oxidation of high-concentration ammonia nitrogen

Fanfeng Yao; Weizhang Fu; Xiaohong Ge; Lingsheng Wang; Jinhua Wang; Wanzhen Zhong

doi:10.1016/j.scitotenv.2020.138425

Preparation and characterization of a copper phosphotungstate/titanium dioxide (Cu-H₃PW₁₂O₄₀/TiO₂) composite and the photocatalytic oxidation of high-concentration ammonia nitrogen

Sci Total Environ. 2020 Jul 20:727:138425. doi: 10.1016/j.scitotenv.2020.138425. Epub 2020 Apr 11.

Authors

Fanfeng Yao¹, Weizhang Fu², Xiaohong Ge¹, Lingsheng Wang¹, Jinhua Wang³, Wanzhen Zhong¹

Affiliations

¹ College of Resources and Environment, Shandong Agricultural University, Taian 271018, PR China.
² College of Resources and Environment, Shandong Agricultural University, Taian 271018, PR China. Electronic address: sdaufwz@163.com.
³ College of Resources and Environment, Shandong Agricultural University, Taian 271018, PR China. Electronic address: wjh@sdau.edu.cn.

PMID: 32330709
DOI: 10.1016/j.scitotenv.2020.138425

Abstract

Currently, the majority of wastewater with a high concentration of ammonia nitrogen (NH₄⁺/NH₃) is treated using biological methods, which have poor biodegradability and low removal efficiency. In this paper, a composite photocatalyst of copper phosphotungstate/titanium dioxide (Cu-H₃PW₁₂O₄₀/TiO₂) was prepared by sol-gel hydrothermal synthesis, and the composite catalyst was characterized by X-ray diffraction (XRD), UV-vis-diffuse reflectance spectroscopy (UV-VIS-DRS), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS)、scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The photocatalytic oxidation of a high-concentration NH₄⁺/NH₃ solution was carried out under ultraviolet (UV) light to explore the effects of different influencing factors on the photocatalytic effect and to optimize the reaction conditions. The prepared composite catalyst exhibited higher photocatalytic activity than that of TiO₂. When the initial concentration of the solution was 300 mg·L^-1, the initial pH was 11, the catalyst concentration was 1.5 g·L^-1, the loading level of Cu-H₃PW₁₂O₄₀ was 40%, and the aeration rate was 1.5 L·min^-1, the removal rate of NH₄⁺/NH₃ by the composite photocatalyst could reach >80%. Very little NO₂^- and NO₃^- were produced, and N₂ was the main product.

Keywords: Characterization; High concentration ammonia nitrogen (NH(4)(+)/NH(3)); Photocatalysis; Polyoxometalates; Titanium dioxide (TiO(2)); Ultraviolet light.