Open AccessComparative Adsorption of Phenol, P-Nitrophenol and P-Hydroxybenzoic Acid on Activated Carbon
Author(s) -
Ewerton Marinho Costa,
Guillermo Calleja,
Luis Marijuán
Publication year - 1988
Publication title -
adsorption science and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.682
H-Index - 36
eISSN - 2048-4038
pISSN - 0263-6174
DOI - 10.1177/026361748800500304
Subject(s) - phenol , chemistry , adsorption , phenols , nitrophenol , activated carbon , carbon fibers , inorganic chemistry , chromatography , organic chemistry , catalysis , materials science , composite number , composite material
Adsorption isotherms of phenol, p-nitrophenol and p-hydroxybenzoic acid at three temperatures in the range 1–40° C on activated carbon have been obtained experimentally. Curve fitting to several theoretical equations shows that the Prausnitz equation gives the lowest deviations (1–3%). An inversion of the adsorption capacity of phenol with temperature has been observed, probably as a consequence of the high microporosity of the carbon and the restricted accessibility of phenol to the smaller pores. Adsorption at 40°C is also accompanied by the degradation of phenol by aerobic micro-organisms (ficomicetus-type fungi). Approximate values of the isosteric heats of adsorption of p-nitrophenol have been calculated, being in the range 5.8–6.5 kcal/mol. Differences in the behaviour of the three adsorbates are commented upon in terms of their physicochemical properties.