Abstract

CARVAJAL-BERNAL, Ana María; GOMEZ, Fernando; GIRALDO, Liliana  and  MORENO-PIRAJAN, Juan Carlos. Adsorption study of 4-nitrophenol from aqueous solution on activated carbon with nitrogen heteroatoms on its surface: application of the Sips Model. Rev.Colomb.Quim. [online]. 2018, vol.47, n.1, pp.27-33. ISSN 0120-2804.  https://doi.org/10.15446/rev.colomb.quim.v47n1.64561.

The amination of a nitric acid pre oxidized activated carbon in the adsorption of 4-nitrophenol was evaluated. The Sips model application to the aqueous solution adsorption data, using Sigmoidal Logistic 3 Parameter formula, in the SigmaPlot 12 program was applied. The obtained parameters were compared with those calculated with Statistica 7 program for Sips and Langmuir models. It was found that the activated carbon increases the adsorption from 2.16 to 2.19 mmol g-1, showing good adsorbent-adsorbate affinity. The system's characteristic energy parameter calculated with the Langmuir model was 377.47 L mmol-1, when not considering energy heterogeneity, while from the Sips model was 8.32 (L.mmol-1)1/n. Additionally, it was found that in the mathematical equation Sigmoidal Logistic 3 Parameter of the SigmaPlot program, the 1/x0 value corresponds to the Langmuir-Freundlich model constant KLF, while the parameter value KS in the Sips model is equal to (1/x0)-b in this program. It was concluded that the 4-nitrophenol adsorption on activated carbon is favored by the presence of nitrogen groups on their activated carbon surface.

Keywords : Sips; Langmuir; Adsorption; Activated carbon; 4-nitrophenol; SigmaPlot.

        · abstract in Spanish | Portuguese     · text in Spanish     · Spanish ( pdf )