title: Full description of copper uptake by algal biomass combining an equilibrium NICA model with a kinetic intraparticle diffusion driving force approach.
abstract: In this work kinetic and equilibrium studies related to copper binding to the protonated macroalga Sargassum muticum are reported. An intraparticle-diffusion linear driving force (LDF) model has been chosen for the quantitative description of the kinetics at several initial metal concentrations. Copper intraparticle homogeneous diffusion coefficient (D(h)) obtained is in the range 0.2-0.9×10(-10) m(2) s(-1). NICA isotherm is demonstrated to constitute a substantial improvement with respect to a simpler Langmuir competitive equation. The binding parameters were chosen to provide the best simultaneous description of the equilibrium experiments. Values of log K(Cu) (4.3), n(Cu) (1) and p (0.31) in NICA isotherm, and log K(Cu) (3.5-5) in Langmuir competitive model, have been obtained. These parameters have been also used to predict the competition between copper and cadmium for binding sites. Two acids, HNO(3) and HCl, have been tested to evaluate their effectiveness to release copper from the metal-laden biomass.
authors.affiliation: Departamento de Química Física e Enxeñería Química I, Universidade da Coruña, Coruña, Spain.
authors.forename: Roberto
authors.initials: R
authors.lastname: Herrero
authors.forename: Pablo
authors.initials: P
authors.lastname: Lodeiro
authors.forename: Lino J
authors.initials: LJ
authors.lastname: García-Casal
authors.forename: Teresa
authors.initials: T
authors.lastname: Vilariño
authors.forename: Carlos
authors.initials: C
authors.lastname: Rey-Castro
authors.forename: Calin
authors.initials: C
authors.lastname: David
authors.forename: Pilar
authors.initials: P
authors.lastname: Rodríguez
mesh_terms: D018533:Biomass; D003198:Computer Simulation; D003300:Copper / Q000737:chemistry* / Q000302:isolation & purification*; D004058:Diffusion; D007700:Kinetics; D008954:Models, Biological; D008956:Models, Chemical; D044647:Sargassum / Q000737:chemistry*
chemical_list: D003300:Copper