resumo
To mitigate the presence of tetracyclines in water, it is essential to implement proper wastewater treatment processes that can effectively remove these compounds. In this work we develop a polymeric filtration membrane functionalized with nanocrystals of a metallic organic framework, designated by HKUST-1. The membrane was evaluated for the remotion of oxytetracycline (OTC), tetracycline (TC), and chlortetracycline (CTC) in water samples. The membrane was fabricated using polysulfone (PSU), polyethyleneglycol (PEG), MOF (HKUST-1), and N-methyl-2-pyrrolidone (NMP) through the nonsolvent induced phase separation (NIPS) method. The membrane that presents the best antibiotic rejection characteristics was prepared with 15 % (w/w) PSU, 3 % (w/w) PEG, 1 % (w/w) HKUST-1, and 81 % (w/w) N-methyl-2-pyrrolidone (NMP). This membrane exhibited a pure water flux of up to 76.2 L.m(-2).h(-1), approximately 40 times more than the one achieved for pristine membranes. Once determined the best membrane composition, a physical-chemical characterization of membrane was done. A high antibiotic rejection rate was obtained for OTC, TC, and CTC, around 91 %, 91 %, and 99 % respectively. The pH of solutions has a strong influence on membrane rejection. The results suggest that intermolecular forces such as pi-pi type interactions and hydrogen bonds exist between the neutral molecules of tetracyclines (pH > pKa(1) and < pKa(2)) and HKUST-1@PSU MMM, which are greater than the electrostatic forces at pH < pKa(1) or pH > pKa(2). Furthermore, FTIR spectra demonstrate the formation of a Cu-tetracycline complex as another adsorption mechanism. Finally, the interaction of the tetracyclines in the mixture on the removal performance was evaluated. The study revealed that chlortetracycline (CTC) exhibited superior removal performance, even over extended periods of time, despite having a lower initial concentration in the mixture. This innovative membrane represents a new generation of highly efficient filter systems specifically designed for water purification purposes.
palavras-chave
METAL-ORGANIC FRAMEWORKS; PERSONAL CARE PRODUCTS; POLYSULFONE MEMBRANES; TREATMENT PLANTS; WASTE-WATER; PHARMACEUTICALS; CONTAMINANTS
categoria
Engineering
autores
Cevallos-Mendoza, JE; Alay-Macias, G; Figueira, F; Araujo, AN; Amorim, CG; Rodríguez-Díaz, JM; Montenegro, MCBSM
nossos autores
Flávio Alberto da Silva Figueira
Investigador Júnioragradecimentos
The work was supported through the projects UIDB/50006/2020 and UIDP/50006/2020, funded by FCT/MCTES through national funds. To the Universidad Tecnica de Manabi for its support for the execution of this research.