title: Hexavalent chromium removal from aqueous solutions by a novel powder prepared from Colocasia esculenta leaves.
abstract: In this study, batch removal of hexavalent chromium from aqueous solutions by powdered Colocasia esculenta leaves was investigated. Batch experiments were conducted to study the effects of adsorption of Cr(VI) at different pH values, initial concentrations, agitation speeds, temperatures, and contact times. The biosorbent was characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier transform infrared spectrometer analysis. The biosorptive capacity of the adsorbent was dependent on the pH of the chromium solution in which maximum removal was observed at pH 2. The adsorption equilibrium data were evaluated for various adsorption isotherm models, kinetic models, and thermodynamics. The equilibrium data fitted well with Freundlich and Halsey models. The adsorption capacity calculated was 47.62 mg/g at pH 2. The adsorption kinetic data were best described by pseudo-second-order kinetic model. Thus, Colocasia esculenta leaves can be considered as one of the efficient and cheap biosorbents for hexavalent chromium removal from aqueous solutions.
authors: a Department of Chemical Engineering , National Institute of Technology Calicut , Kozhikode , Kerala , India.
authors: E
authors: E
authors: Nakkeeran
authors: a Department of Chemical Engineering , National Institute of Technology Calicut , Kozhikode , Kerala , India.
authors: N
authors: N
authors: Saranya
authors: a Department of Chemical Engineering , National Institute of Technology Calicut , Kozhikode , Kerala , India.
authors: M S
authors: MS
authors: Giri Nandagopal
authors: b School of Biotechnology, National Institute of Technology Calicut , Kozhikode , Kerala , India.
authors: A
authors: A
authors: Santhiagu
authors: a Department of Chemical Engineering , National Institute of Technology Calicut , Kozhikode , Kerala , India.
authors: N
authors: N
authors: Selvaraju
mesh_terms: D065966:Absorption, Physicochemical; D002274:Carcinogens, Environmental / Q000302:isolation & purification*; D002857:Chromium / Q000302:isolation & purification*; D031060:Colocasia; D018515:Plant Leaves; D011208:Powders; D012996:Solutions; D018508:Water Purification / Q000379:methods*
chemical_list: D002274:Carcinogens, Environmental; D011208:Powders; D012996:Solutions; D002857:Chromium; C074702:chromium hexavalent ion
keywords: Colocasia esculenta; FTIR; biosorption; hexavalent chromium; isotherms; thermodynamic parameters