Adsorption of Phenolic Compounds from Water on Activated Carbon: Prediction of Multicomponent Equilibrium Isotherms using Single-Component Data

Abstract

Batch-type experiments were carried out to obtain equilibrium isotherms for the adsorption of phenol and m-cresol in aqueous solutions on activated carbon. Single solute systems, at 20 and 40 • C, were tested for Langmuir, Freundlich and Sips adsorption isotherms in the range of concentrations up to 200 mg/L. Equilibrium data were more closely followed by the Freundlich and Sips equations for all cases. Adsorption isotherms for bisolute systems at 20 • C, with two different initial concentrations of phenol and m-cresol, were predicted solely on the basis of single solute equilibrium parameters by using the equations of Butler and Ockrent and the IAS theory. The best agreement with the experimental loading values was afforded with the IAS theory based on Sips isotherm for pure compounds. However, this theory is found to be not able to predict with success the binary isotherms in this work where significant displacement of one solute by the other is observed. Chemical interactions in the adsorbed phase, estimated by a modified Butler-Ockrent model, can be responsible for this lack of success of the conventional IAS theory. The predictions based on the IAS theory are compared with the results of some empirical models.

Functionalization of Microcrystalline Cellulose with N,N-dimethyldodecylamine for the Removal of Congo Red Dye from an Aqueous Solution

“…In comparison with these methods, adsorption is a low cost and highly efficient method that can be used to remove colored matter from dye wastewater, and as such it has attracted increasing attention for improving the purity of water resources (Leitão and Serrão 2005;Qadeer 2007). Adsorption using activated carbon as adsorbent is an important method to purify colored wastewater because of its excellent physical properties (Yin et al 2008).…”

Atomistic calculation of adsorption in activated carbon with pore-size distribution

“…Single-component adsorption of these two components was experimentally studied by Leitao and Serrao on Nuchar WA-activated carbon [18]. We later study the competitive adsorption of these two components.…”

“…Methods that attempt to predict the multicomponent adsorption from singlecomponent data often fail to predict the isotherm in cases where adsorbate-adsorbate interaction occurs [15,16,18]. The Freundlich multicomponent isotherm requires single-component data as well as a competition coefficient which had to be determined experimentally.…”

“…The Freundlich adsorption isotherm has been widely applied in describing experimental adsorption of organic pollutants in aqueous solutions, including that of phenol and phenolic compounds [15][16][17][18]. The Freundlich isotherm has been originally accounted for by Langmuir adsorption while an exponential distribution of adsorption energies is assumed.…”

Biosorption of Phenol and Cyanide from Synthetic/Simulated Wastewater by Sugarcane Bagasse—Equilibrium Isotherm and Kinetic Analyses

“…In binary component aqueous solution, the components present in solution may have three types of sorption interaction effects such as if the adsorption of the adsorbate decrease when there are additional adsorbates present in the binary component mixture (antagonism Q mix /Q i < 1), the adsorption of the adsorbate increase when there are another adsorbates present in the binary component mixture (synergism Q mix / Q i > 1), and if the binary component mixture has no effect on the adsorption of each adsorbate (non-interaction Q mix / Q i = 1) [32], where Q i is the biosorption capacity of Table 2, founding the fact that both phenol and cyanide show synergism effects. The experimental equilibrium sorption data obtained for the mono-component and the binary systems show that the adsorption capacity of sugarcane bagasse for phenol is, in general, more than that of cyanide.…”