Acetaminophen Adsorption on Carbon Materials from Citrus Waste

Autor: Marwa Gatrouni, Nedra Asses, Jorge Bedia, Carolina Belver, Carmen B. Molina, Nadia Mzoughi
Jazyk: angličtina
Rok vydání: 2024
Předmět:
Zdroj: C, Vol 10, Iss 2, p 53 (2024)
Druh dokumentu: article
ISSN: 2311-5629
40319679
DOI: 10.3390/c10020053
Popis: Biochar and carbon adsorbents from citrus waste have been prepared by thermal and chemical treatments; they have been used in the aqueous phase adsorption of acetaminophen (ACE) as a model emerging pollutant. These materials were fully characterized by elemental analysis, X-ray fluorescence (TXRF), adsorption/desorption of nitrogen, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), point of zero charge (pHpzc), scanning electron microscopy (SEM), and thermogravimetric analyses (TGA/DTG/DTA). A magnetic carbon adsorbent was obtained by FeCl3 activation under an inert atmosphere, giving rise to the best results in ACE adsorption. Adsorption equilibrium data were obtained at 298, 318, and 338 K and fitted to different models, corresponding to the best fitting to the Redlich–Peterson model. The maximum adsorption capacity at equilibrium resulted in 45 mg ACE·g−1 carbon at 338 K. The free energy values were calculated, and values between −21.03 and −23.00 kJ·mol−1 were obtained; the negative values confirmed the spontaneity of the process. The enthalpy and entropy of the adsorption process were obtained, giving rise to −6.4 kJ·mol−1 and 49 J·mol−1·K−1, respectively, indicating a slightly exothermic process and an increase in the randomness at the solid–liquid interface upon adsorption, respectively. The adsorption kinetics were also studied, with the Elovich model being the one that gave rise to the best-fitting results.
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