Propranolol adsorption onto multiwalled carbon nanotubes modified by green synthesis: pH, kinetic, and equilibrium studies

• Published in: Environmental science and pollution research international 2024-09, Vol.31 (41), p.53642-53654
• Main Authors: Spaolonzi, Marcela Pires, Oliveira, Mariana Gomes, Ribeiro, Mariana Cardoso Barros, da Silva, Meuris Gurgel Carlos, Vieira, Melissa Gurgel Adeodato
• Format: Article
• Language: English
• Subjects: Adsorption; Adsorption Processes for Environmental Issues; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Carbon; Charge materials; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Equilibrium; Multi wall carbon nanotubes; Nanotechnology; Nanotubes; pH effects; Propranolol; Speciation; Thermal regeneration; Waste Water Technology; Water Management; Water Pollution Control
• ISSN: 1614-7499; 0944-1344; 1614-7499
• DOI: 10.1007/s11356-023-31320-y

This research investigated the adsorption of propranolol (PROP) by functionalized green carbon nanotubes (MWCNT-B), assessing the influence of pH, in addition to kinetic, equilibrium, and thermodynamic studies and reuse of the material. For this purpose, speciation of PROP and the point of zero charge (pH PZC ) of MWCNT-B were performed, indicating a pKa of 9.67 and pH PZC of 3.31. The adsorption tests at different pH values revealed that in the range of pH 3 to 9, there is no significant variation in PROP uptake, despite this, at pH 11, the removal decreases. Regarding PROP adsorption, the equilibrium time ranged from 30 to 90 min, and the PFO model best represented the kinetic data. The Langmuir model was more predictive in representing isotherms ( R 2  > 0.95), and the adsorption process was spontaneous and favorable (Δ G