title: A natural sorbent, Luffa cylindrica for the removal of a model basic dye.
abstract: In this work, application of Luffa cylindrica in malachite green (MG) removal from aqueous solution was studied in a batch system. The effect of contact time, pH and temperature on removal of malachite green was also investigated. By the time pH was increased from 3 to 5, the amount of sorbed malachite green also increased. Beyond the pH value of 5, the amount of sorbed malachite green remains constant. The fits of equilibrium sorption data to Langmuir, Freundlich and Dubinin-Radushkevich equations were investigated. Langmuir isotherm exhibited best fit with the experimental data. Monolayer sorption capacity increased with the increasing of temperature. Sorption kinetic was evaluated by pseudo-first-order, pseudo-second-order, Elovich rate equations and intraparticle diffusion models. It was inferred that sorption follows pseudo-second-order kinetic model. Thermodynamic parameters for sorption process were also found out. Spontaneous and endothermic nature of sorption was obtained due to negative value of free energy (DeltaG(o)) and positive value of enthalpy (DeltaH(o)) changes. FTIR analyses were also conducted to confirm the sorption of malachite green onto L. cylindrica.
authors.affiliation: Dokuz Eylül University, Faculty of Arts and Sciences, Department of Chemistry, Tinaztepe Campus, Buca Izmir, Turkey.
authors.forename: Aylin
authors.initials: A
authors.lastname: Altinişik
authors.forename: Emel
authors.initials: E
authors.lastname: Gür
authors.forename: Yoldaş
authors.initials: Y
authors.lastname: Seki
mesh_terms: D000327:Adsorption; D004396:Coloring Agents / Q000737:chemistry / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D029776:Luffa / Q000737:chemistry*; D012394:Rosaniline Dyes / Q000737:chemistry / Q000302:isolation & purification*; D012996:Solutions; D013055:Spectrophotometry, Infrared; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D013816:Thermodynamics; D018508:Water Purification
chemical_list: D004396:Coloring Agents; D012394:Rosaniline Dyes; D012996:Solutions; C005095:malachite green