Work

Molecular-level analysis of coagulation mechanism in polyamide and norfloxacin composite system

Year: 2025

Type: article

Abstract: Microplastics (MPs) and antibiotics will influence each other's removal efficiency during coagulation process. This study investigated the coagulation performance and mechanism of polyamide (PA) (pristine PA (PA-O) and aged PA (PA-A)) and norfloxacin (NOR) in single and composite system. The optimal removal efficiency was achieved 73–90 % for PA-O, 80–92 % for PA-A, 30–41 % (PA-O@NOR) and 23–41 % (PA-A@NOR) for NOR in composite system. Mechanism study found the reaction between oxygen-containing groups and aluminum species was crucial during coagulation process. PA-O could be complexed with Al 3+ through amide group, while PA-A could react with the active groups (η-H 2 O and η-OH) on aluminum hydrolysate species through -OH. As more oxygen-containing groups participated in the reaction, PA-A exhibited advantage of coagulation compared to PA-O. And NOR could either be complexed with Al 3+ or react with the active groups by the oxygen of -C=O and -COOH. Thus, there was a competition between NOR and PA in composite system. Moreover, humic acid (HA) competed with PA and NOR for aluminum hydrolysis products, inhibiting the removal of PA and NOR. This inhibition was more pronounced for PA than for NOR, as HA enhanced the phase transfer of NOR.

Source: Journal of Water Process Engineering

DOI: 10.1016/j.jwpe.2025.108709

Authors: Jing He, Kening Tian, Jing Yang, Liangyan He

Institution: Southwest University of Science and Technology

Language: English

Topic: Coagulation and Flocculation Studies

Subfield: Water Science and Technology

Field: Environmental Science

Domain: Physical Sciences

SDGs: Clean water and sanitation, Responsible consumption and production

Open Access status: hybrid

Estimated APC paid: $3,350