Photoactive and metal-free polyamide-based polymers for water and wastewater treatment under visible light irradiation

• Published in: Applied catalysis. B, Environmental Vol. 193; pp. 226 - 233
• Main Authors: Shen, Junjie, Steinbach, Roman, Tobin, John M., Mouro Nakata, Mayumi, Bower, Matthew, McCoustra, Martin R.S., Bridle, Helen, Arrighi, Valeria, Vilela, Filipe
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.09.2016
• Subjects: Backbone; Bisphenol A; Cimetidine; Contaminants; Cryptosporidium; Heterogeneous photosensitizer; Metal-free polymerization; Monomers; Polyamide resins; Polymers; Singlet oxygen; Visible light photoactivation; Water purification; Water treatment; FFA; MPD; PBS; Water treatment; Pd(PPh3)4; PA-ABT (x%); Heterogeneous photosensitizer; Visible light photoactivation; TMC; PA; BPA; BT; ABT; Singlet oxygen; BBT; Metal-free polymerization
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2016.04.015

[Display omitted] •Cost-effective and metal-free synthesis of organic polyamide-based photosensitizers.•Visible light photoactivation of the polyamide-based photosensitizers.•Effective in photodegrading organic contaminants and inactivating Cryptosporidium.•Good photochemical stability under extreme water pH conditions. A photoactive benzothiadiazole (BT) based monomer was developed and used in the synthesis of typical polyamide (PA) polymers. The monomer was incorporated in different percentages within the PA backbone of the polymers and their photosensitising ability was tested in different media and conditions. Photochemical experiments in a commercial flow reactor under aerobic conditions showed that the polymers had increased efficiency in singlet oxygen generation compared to the original photoactive monomer. When suspended in aqueous solutions, these materials demonstrated superior photostability towards long-term exposure to light and chemical stability in a wide-range of pH environments. The photoactive polymers were highly capable of degrading two well-known wastewater contaminants, bisphenol A (BPA) and cimetidine, as well as inactivating the waterborne parasite Cryptosporidium. Given the simplicity of the synthetic preparation of the polymers, the absence of metals and their photoactivity under visible light, herein we show that these materials are very promising for simultaneous decontamination and disinfection of water.