title: Use of papaya seeds as a biosorbent of methylene blue from aqueous solution.
abstract: In this study papaya seeds were used to remove methylene blue dye from aqueous solution. Papaya seeds were characterized as possessing a macro/mesoporous texture and large pore size. Studies were carried out in batches to evaluate the effect of contact time and pH (2-12) on the removal of dye. It was observed that the adsorption of dye was better in the basic region (pH 12). The equilibrium data were analyzed using Langmuir, Freundlich, Dubinin-Raduschkevich, Tempkin, Jovanovich, Redlich-Peterson, Sips, Toth and Radke-Prausnitz isotherms. The equilibrium data were best described by the Langmuir isotherm with a maximum adsorption capacity of 637.29 mg g(-1). Adsorption kinetic data were fitted using the pseudo-first-order and pseudo-second-order model. The adsorption kinetic is very fast and was best described by the pseudo-second-order model.
authors.affiliation: Department of Chemical Engineering, Federal University of Santa Maria, Santa Maria, 97105-900, Brazil.
authors.forename: Diego S
authors.initials: DS
authors.lastname: Paz
authors.forename: Alexandre
authors.initials: A
authors.lastname: Baiotto
authors.forename: Marcio
authors.initials: M
authors.lastname: Schwaab
authors.forename: Marcio A
authors.initials: MA
authors.lastname: Mazutti
authors.forename: Mariana M
authors.initials: MM
authors.lastname: Bassaco
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Bertuol
authors.forename: Edson L
authors.initials: EL
authors.lastname: Foletto
authors.forename: Lucas
authors.initials: L
authors.lastname: Meili
mesh_terms: D000327:Adsorption; D029441:Carica; D004396:Coloring Agents / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008751:Methylene Blue / Q000737:chemistry*; D012639:Seeds / Q000737:chemistry*; D013696:Temperature; D014865:Waste Disposal, Fluid / Q000379:methods; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D004396:Coloring Agents; D014874:Water Pollutants, Chemical; D008751:Methylene Blue