title: Comparison between Brazilian agro-wastes and activated carbon as adsorbents to remove Ni(II) from aqueous solutions.
abstract: This research was performed to find an alternative, low-cost, competitive, locally available and efficient adsorbent to treat nickel (Ni) containing effluents. For this purpose, several Brazilian agro-wastes like sugarcane bagasse (SCB), passion fruit wastes (PFW), orange peel (OP) and pineapple peel (PP) were compared with an activated carbon (AC). The adsorbents were characterized. Effects of fundamental factors affecting the adsorption were investigated using batch tests. Kinetic and equilibrium studies were performed using conventional models. It was verified that the adsorption was favored at pH of 6.0 for all agro-wastes, being dependent of the Ni speciation, point of zero charge and surface area of the adsorbents. The Ni removal percentage was in the following order: SCB > OP > AC > PFW > PP. From the kinetic viewpoint, the Elovich model was appropriate to fit the Ni adsorption onto SCB, while for the other adsorbents, the pseudo-first-order model was the most suitable. For all adsorbents, the Langmuir model was the more adequate to represent the equilibrium data, being the maximum adsorption capacities of 64.1 mg g(-1), 60.7 mg g(-1), 63.1 mg g(-1), 48.1 mg g(-1) and 64.3 mg g(-1) for SCB, PFW, OP, PP and AC, respectively. These results indicated that mainly SCB and OP can be used as alternative adsorbents to treat Ni containing effluents.
authors.affiliation: Environmental Processes Laboratory (LAPAM), Chemical Engineering Department, Federal University of Santa Maria, Santa Maria 97105-900, Brazil E-mail: guilherme_dotto@yahoo.com.br.
authors.forename: Guilherme Luiz
authors.initials: GL
authors.lastname: Dotto
authors.affiliation: Separation Systems and Process Optimization Laboratory, Center of Technology, Federal University of Alagoas, Maceió 57072-970, Brazil.
authors.forename: Lucas
authors.initials: L
authors.lastname: Meili
authors.affiliation: Food Technology Department, Center of Exact Sciences and Technology, Federal University of Sergipe, Aracaju 49100-000, Brazil.
authors.forename: Ana Karla
authors.initials: AK
authors.lastname: de Souza Abud
authors.affiliation: Environmental Processes Laboratory (LAPAM), Chemical Engineering Department, Federal University of Santa Maria, Santa Maria 97105-900, Brazil E-mail: guilherme_dotto@yahoo.com.br.
authors.forename: Eduardo Hiromitsu
authors.initials: EH
authors.lastname: Tanabe
authors.affiliation: Environmental Processes Laboratory (LAPAM), Chemical Engineering Department, Federal University of Santa Maria, Santa Maria 97105-900, Brazil E-mail: guilherme_dotto@yahoo.com.br.
authors.forename: Daniel Assumpção
authors.initials: DA
authors.lastname: Bertuol
authors.affiliation: Environmental Processes Laboratory (LAPAM), Chemical Engineering Department, Federal University of Santa Maria, Santa Maria 97105-900, Brazil E-mail: guilherme_dotto@yahoo.com.br.
authors.forename: Edson Luiz
authors.initials: EL
authors.lastname: Foletto
mesh_terms: D000327:Adsorption; D031230:Ananas; D018533:Biomass; D001938:Brazil; D002606:Charcoal / Q000737:chemistry*; D032084:Citrus sinensis; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008956:Models, Chemical; D008962:Models, Theoretical; D009532:Nickel / Q000302:isolation & purification*; D029598:Passiflora; D031786:Saccharum; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*
chemical_list: D014874:Water Pollutants, Chemical; D002606:Charcoal; D009532:Nickel