Biosorption of cadmium by the protonated macroalga Sargassum muticum: Binding analysis with a nonideal, competitive, and thermodynamically consistent adsorption (NICCA) model
Sastre de Vicente, Manuel E.
Barriada, José L.
MetadataShow full item record
Protonated biomass of the seaweed Sargassum muticum was investigated for its ability to remove cadmium(II) from aqueous solutions. In this work, a nonideal, semiempirical, thermodynamically consistent (NICCA) isotherm was proposed to fit the experimental ion binding data obtained in NaNO3 0.05 mol L−1. This model describes the competition between protons and metal ions satisfactorily. Moreover, it reflects the complexity of the macromolecular systems that take part in biosorption considering the heterogeneity of the sorbent. It was demonstrated in this work that the NICCA isotherm constitutes a great improvement with respect to a simpler Langmuir competitive equation, which was not able to describe all the experimental data satisfactorily. Potentiometric acid–base titrations in the absence of cadmium were made to estimate the maximum amount of acid functional groups (2.61 mmol g−1) and the conditional proton binding parameters, logK˜H (3.8) and mH (0.54). The values of the binding parameters for the cadmium ion were chosen to provide the best simultaneous description of the isotherm at pH 4.5, as well as the dependence of cadmium adsorption on pH. Values of logK˜Cd (3.1), nCd (1.8), and p (0.19) in the case of the NICCA isotherm or logKCd (2.94–3.4) for Langmuir competitive models were obtained. Kinetic experiments were performed at two different pH values (3.0 and 4.5), establishing the time dependence that represents the sorption of cadmium with a pseudo-second-order kinetic model. It was observed that 4 h is enough to ensure that the equilibrium uptake was reached.
Is part ofJournal of Colloid and Interface Science, 2005, vol. 289, núm. 2, p. 352-358
European research projects
Showing items related by title, author, creator and subject.
Experimental evidences for a new model in the description of the adsorption-coupled reduction of Cr(VI) by protonated banana skin López García, Marta; Lodeiro, Pablo; Herrero, Roberto; Barriada, José L.; Rey Castro, Carlos; David, Calin; Sastre de Vicente, Manuel E. (Elsevier, 2013)This work reports experimental evidences, not previously considered, to evaluate the Cr(VI) removal by protonated banana skin biomass. Variations in the number of hydroxyl groups, quantified by potentiometric titrations, ...
Herrero Rodríguez, Roberto; Cordero Pérez, Bruno; Lodeiro, Pablo; Rey Castro, Carlos; Sastre de Vicente, Manuel E. (Elsevier, 2006)Samples of dead biomass from the marine brown algae Fucus ceranoides, F. vesiculosus and F.serratus were studied for their ability to remove cadmium from aqueous solutions. The metal sorption process is rapid, with 90% ...
Removal of inorganic mercury from aqueous solutions by biomass of the marine macroalga Cystoseira Baccata Herrero, Roberto; Lodeiro, Pablo; Vilariño, Teresa; Sastre de Vicente, Manuel E.; Rey Castro, Carlos (Elsevier, 2005)The ability of Cystoseira baccata algal biomass to remove Hg(II) from aqueous solutions is investigated. The mercury biosorption process is studied through batch experiments at 25ºC with regard to the influence of contact ...