Efficient Chemical-Free Degradation of Waterborne Micropollutants with an Immobilized Dual-Porous TiO2 Photocatalyst

Daniel E Willis; Ella C Sheets; Mary R Worbington; Madhusudan Kamat; Sarah K Glass; MaCayla J Caso; Tochukwu Ofoegbuna; Liz M Diaz; Caleb Osei-Appau; Samuel D Snow; Kevin M McPeak

doi:10.1021/acsestengg.3c00191

Efficient Chemical-Free Degradation of Waterborne Micropollutants with an Immobilized Dual-Porous TiO₂ Photocatalyst

ACS ES T Eng. 2023 Aug 3;3(11):1694-1705. doi: 10.1021/acsestengg.3c00191. eCollection 2023 Nov 10.

Affiliations

¹ Gordon and Mary Cain Department of Chemical Engineering, Louisiana State University, Baton Rouge, Louisiana 70803, United States.
² Department of Civil and Environmental Engineering, Louisiana State University, Baton Rouge, Louisiana 70803, United States.

Abstract

Photocatalytic advanced oxidation processes (AOPs) promise a chemical-free route to energy-efficient degradation of waterborne micropollutants if long-standing mass transfer and light management issues can be overcome. Herein, we developed a dual-porous photocatalytic system consisting of a mesoporous (i.e., 2-50 nm pores) TiO₂ (P25) photocatalyst supported on macroporous (i.e., >50 nm pores) fused quartz fibers (P25/QF). Our reusable photocatalytic AOP reduces chemical consumption and exhibits excellent energy efficiency, demonstrated by degrading various pharmaceutical compounds (acetaminophen, sulfamethoxazole, and carbamazepine) in natural waters with electrical energy per order (E_EO) values of 4.07, 0.96, and 1.35 kWh/m³, respectively. Compared to the conventional H₂O₂/UVC AOP, our photocatalytic AOP can treat water without chemical additives while reducing energy consumption by over 2800%. We examine these improvements based on mass transport and optical (UVA and UVC) transmittance and demonstrate that the enhancements scale with increasing flow rate.