2017/06/28 by Wina Rongchapo, Chalermpan Keawkumay, Nattawut Osakoo +4
Biochemistry, Genetics and Molecular Biology · Environmental Science · Medicine · #Arsenic contamination and mitigation #Electron Spin Resonance Studies #Paraquat toxicity studies and treatments
paper · pdf · doi:10.1177/0263617417715394
openalex publication_date 2017/06/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/29
The nature of paraquat adsorption is compared between zeolite NaX and NaY which have the same faujasite structure but different Si/Al ratio, namely 1.2 and 2.2, respectively. The adsorption was proposed to occur via ion exchange and expected to increase with Al content. However, NaX had a lower paraquat adsorption capacity than NaY. The bare and paraquat-containing zeolites (PQX and PQY) were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, N 2 adsorption–desorption analysis, magic-angle spinning nuclear magnetic resonance (MAS) NMR, and X-ray photoelectron spectroscopy. The presence of adsorbed paraquat was confirmed by Fourier transform infrared spectroscopy. Paraquat adsorbed in supercages of the zeolites resulting in a decrease of surface area and displacement of sodium cations. Results from 23 Na MAS NMR and X-ray photoelectron spectroscopy indicated that interaction of sodium ions in the cavity of NaX was stronger than that in NaY, making it less exchangeable with paraquat.