Metal-free high-adsorption-capacity adsorbent derived from spent coffee grounds for methylene blue.

ABSTRACT: Heavy-metal-free carbon materials were prepared from spent coffee grounds (SCG) using the coupled KOH-urea and NaOH-urea as activating agents, and these were compared with SCG activation by the alkali salts alone. SCG was impregnated with the activating agents before being pyrolyzed at 800 °C under a N₂ atmosphere. Characterization of the as-pyrolyzed carbon materials was performed by field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and measurement of N₂ adsorption-desorption isotherms. The carbon materials were utilized for the adsorption of methylene blue (MB) in aqueous solutions. Combining KOH and urea as activating agents resulted in t

SUBMITTER: Sukhbaatar B 

PROVIDER: S-EPMC8694667 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature