title: Isotherm Model Analysis for the Adsorption of Cd (II), Cu (II), Ni (II), and Zn (II) on Anaerobically Digested Sludge.
abstract: Adsorption of Cd (II), Cu (II), Ni (II), and Zn (II) from aqueous solutions on anaerobically digested sludge has been investigated. Experimental data has been fit to Langmuir, Freundlich, and Redlich-Peterson isotherms to obtain the characteristic parameters of each model. Based on the maximum adsorption capacity obtained from the Langmuir and the Redlich-Peterson isotherm the affinity of the studied metals for the sludge has been established as Cu (II)>Cd (II)>Zn (II)>Ni (II). Adsorption tests from multimetal systems confirm the affinity order obtained in the individual metal tests. The adsorption capacity for Cu (II) measured in individual tests is not reduced by the presence of the other above referred metals. Desorption of Zn (II) and Cd (II) previously bound to the sludge in front of Cu (II) and HCl solutions is also reported. Copyright 2000 Academic Press.
authors.affiliation: Laboratori d'Enginyeria Química i Ambiental, Departament d'Enginyeria Química, Agrària i Tecnologia Agroalimentària, Facultat de Ciències, Universitat de Girona, Campus de Montilivi, Girona, 17071, Spain
authors.initials: A
authors.lastname: Artola
authors.initials: M
authors.lastname: Martin
authors.initials: M
authors.lastname: Balaguer
authors.initials: M
authors.lastname: Rigola