Adsorption of Acid Blue 129 from Aqueous Solutions onto Raw and Surfactant-Modified Bentonite: Application of Temperature-Dependent Forms of Adsorption Isotherms

Abstract

Modification of raw bentonite from Ponorogo, East Java, Indonesia by microwave irradiation using cetyltrimethylammonium bromide (CTAB) was studied. The adsorption capabilities of raw bentonite and its modified form were examined through their use in the removal of Acid Blue 129 from aqueous solution. The adsorption isotherm and kinetic experiments were conducted at four temperatures (25, 30, 40 and 50 ºC). The fitting of the corresponding experimental data was tested using the temperature-dependent forms of the Langmuir, Freundlich, Sips and Toth equations. The Sips equation gave a better representation of the adsorption data, together with reasonable values of the fitted parameters. Two well-known kinetic models, the pseudo-first-and pseudo-secondorder, were used to correlate the adsorption kinetic data, with the pseudo-first-order model giving the better results. Both physical and chemical adsorption mechanisms occurred during the adsorption process, with the main controlling mechanism being physical adsorption.

Equilibrium, kinetic and thermodynamic studies on the removal of U(VI) by low cost agricultural waste

“…From all the modified treatments, SDS-treated RH showed maximum U(VI) removal and was selected for further biosorption optimization studies. This finding is complimentary to the work of Chen et al [15], and Yesi et al [14] who reported an increase in sorption capacity of surfactant modified silkworm exuviae and Bentonite respectively.…”

“…Surfactant pre-treatment introduces lyophobic and lyophilic groups capable of adsorbing at the biosorbent surface:solution interface. The adsorption of heavy metals onto biomass from aqueous solution can be enhanced in the presence of surfactants due to reduced surface tension and increased wetting power [14]. From all the modified treatments, SDS-treated RH showed maximum U(VI) removal and was selected for further biosorption optimization studies.…”

Kinetics and thermodynamic studies for removal of acid blue 129 from aqueous solution by almond shell

“…As is seen in Table 5 the contact time for proposed method in comparison with all of the adsorbents are preferable and superior to the literature which show satisfactory removal performance for AB129 as compared to other reported adsorbents [46,47]. …”

Evaluation of cassava peel waste as lowcost biosorbent for Ni-sorption: Equilibrium, kinetics, thermodynamics and mechanism

“…The temperature dependence forms of several adsorption isotherm models are adopted to correlate adsorption equilibrium data. In our previous studies, these particular models have been successfully applied to evaluate the adsorption equilibrium data of several organic compounds onto organo-clay [6,7].…”