Resumen

ARELLANO-CARDENAS, Sofía et al. Adsorption of Phenol and Dichlorophenols from Aqueous Solutions by Porous Clay Heterostructure (PCH). J. Mex. Chem. Soc [online]. 2005, vol.49, n.3, pp.287-291. ISSN 1870-249X.

Experiments have been conducted to examine the adsorption of phenol and dichlorophenols (2,5 DCP and 3,4 DCP) from water by a Porous Clay Heterostructure (PCH). Experiments were carried out for the analysis of adsorption equilibrium capacities using a batch equilibrium technique. The Freundlich adsorption model was best to describe adsorption equilibrium data for dichorophenols (r² = 0.994 for 3,4 DCP and r² = 0.993 for 2,5 DCP). In the case of the adsorption of phenol, the isotherm model of Langmuir was best to describe the experimental data (r² = 0.9839) at high equilibrium concentrations (0-500 ppm), while at low equilibrium concentrations (020 ppm) the Freundlich model was best to describe the data (r² = 0.9831). This deviation implies that the adsorption sites are heterogeneous. The adsorption capacity showed by the PCH for both phenol and DCPs from water (48.7 mg/g for 3,4-DCP, 45.5 mg/g for 2,5- DCP and 14.5 mg/g for phenol), suggests that the PCH have both, hydrophobic and hydrophilic characteristics, due to the presence of silanol and siloxane groups formed during the pillaring and preparation of the PCH.

Palabras llave : clay; PCH; phenol adsorption; dichlorophenols adsorption.