Sustained oxidation of Tea-Fe(III)/H2O2 simultaneously achieves sludge reduction and carbamazepine removal: The crucial role of EPS regulation

• Published in: Journal of hazardous materials 2024-05, Vol.470, p.134182, Article 134182
• Main Authors: Lin, Wei, Chen, Renglu, Gong, Chuangxin, Desmond, Peter, He, Xu, Nan, Jun, Li, Guibai, Ma, Jun, Ding, An, Ngo, Huu Hao
• Format: Article
• Language: English
• Subjects: Carbamazepine; Extracellular polymeric substances; Sludge dewaterability; Tea waste; Treating waste with waste
• ISSN: 0304-3894; 1873-3336; 1873-3336
• DOI: 10.1016/j.jhazmat.2024.134182

Establishing an economic and sustained Fenton oxidation system to enhance sludge dewaterability and carbamazepine (CBZ) removal rate is a crucial path to simultaneously achieve sludge reduction and harmless. Leveraging the principles akin to "tea making", we harnessed tea waste to continually release tea polyphenols (TP), thus effectively maintaining high level of oxidation efficiency through the sustained Fenton reaction. The results illustrated that the incorporation of tea waste yielded more favorable outcomes in terms of water content reduction and CBZ removal compared to direct TP addition within the Fe(III)/hydrogen peroxide (H2O2) system. Concomitantly, this process mainly generated hydroxyl radical (•OH) via three oxidation pathways, effectively altering the properties of extracellular polymeric substances (EPS) and promoting the degradation of CBZ from the sludge mixture. The interval addition of Fe(III) and H2O2 heightened extracellular oxidation efficacy, promoting the desorption and removal of CBZ. The degradation of EPS prompted the transformation of bound water to free water, while the formation of larger channels drove the discharge of water. This work achieved the concept of treating waste with waste through using tea waste to treat sludge, meanwhile, can provide ideas for subsequent sludge harmless disposal. [Display omitted] •The concept of tea-making is utilized for improving Fe(III)/H2O2 oxidation ability.•The sustained release of tea polyphenols maintains efficient cycle of Fe(II)/Fe(III).•The destruction of hydrogen bond and sustained oxidation leads to CBZ removal.•Extracellular oxidation promotes the desorption of CBZ from EPS-CBZ complex.