Immobilizing a visible light-responsive photocatalyst on a recyclable polymeric composite for floating and suspended applications in water treatment

Ch Tahir Mehmood; Ziyi Zhong; Hua Zhou; Chenchen Zhang; Yeyuan Xiao

doi:10.1039/d0ra06864k

Immobilizing a visible light-responsive photocatalyst on a recyclable polymeric composite for floating and suspended applications in water treatment

RSC Adv. 2020 Oct 1;10(60):36349-36362. doi: 10.1039/d0ra06864k.

Authors

Ch Tahir Mehmood¹, Ziyi Zhong², Hua Zhou³, Chenchen Zhang², Yeyuan Xiao¹

Affiliations

¹ Department of Civil and Environmental Engineering, College of Engineering, Shantou University Shantou Guangdong 515063 China yeyuanxiao@stu.edu.cn.
² Department of Chemical Engineering, Guangdong Technion - Israel Institute of Technology Shantou Guangdong 515063 China.
³ Guangdong Guangye Environmental Protection Industrial Group Co., Ltd. Guangzhou Guangdong China.

Abstract

A visible light responsive TiO₂/Ag₃PO₄ (10 : 1) nanocomposite was prepared and successfully immobilized (12 wt%) in a spherical polymeric matrix consisting of polysulfone and alginate (10 : 6). The resulted beads featured a sponge-like structure with interconnected macrovoids and micropores, and showed high adsorption and visible-light photocatalytic activity towards various wastewater pollutants, including the widely used dye - methylene blue (k = 0.0321 min^-1), and two emerging pharmaceutical contaminants - diclofenac (k = 0.018 min^-1) and triclosan (k = 0.052 min^-1). As determined, the ˙OH radical and h⁺ are the primary reactive oxygen species responsible for the photodegradation. The composite photocatalytic beads are also effective in bacterial inactivation and degradation of acyl-homoserine lactones (AHLs), the bacterial quorum sensing autoinducers triggering biofilms, thus exhibiting a promising future in wastewater disinfection and biofilm retardation. Additionally, these beads could be used in inter-switchable suspended or buoyant forms, and be effectively regenerated by H₂O₂ treatment, and used for multiple cycles without any significant loss in photoactivity. With these unique features, the prepared visible-light photocatalytic beads could be easily applied in large-scale water and wastewater treatment systems.