In this work they were studied the characteristics of surface of CAG commercial in natura
(CA-1) and treated for (HNO3) (CA-2) and their applications in the adsorption of benzene
and tolueno. Characterization of the adsorventes: specific superficial area - SBET and
distribution of pores (adsorption of N2/77 K), pH (norm ASTM D3838-05), functional groups
of surface (FTIR and method of Boehm). Adsorption tests were performed in batch system
and fixed bed column (25 ° C/140 rpm/25 minutes), where the samples were quantified by gas
chromatography with headspace extraction by EPA method 0010. The SBET and the average
volume of the pores of the adsorbent CA-2 decreased with relation to the values of CA1 as
well as the pH. There was an increase of acidic functional groups determined by the method
Boehm of the adsorbent CA-2 in relation to CA-1, which was confirmed by determining
FTIR, in which the intensity of the absorption bands were more intense for CA-2.
Test data were fitted satisfactorily by kinetic mathematical model of pseudo-second order,
based on statistical tests applied, with statistically significant differences between the treated
adsorbent (CA-2) and in natura (CA-1). Assays were performed equilibrium adsorption, and
the results correlated by the Langmuir isotherm, with satisfactory response for that model.
From the adsorption system in a fixed bed column and considering the highest volumetric
flow (Q = 100 mL / min) used in this system yielded the most important results of adsorption
of benzene and toluene using (CA-2) as adsorbent.
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