Kinetic and isotherm parameter determination for the removal of chromium from aqueous solutions by nanoalumina, a nanoadsorbent

Nanoalumina has been employed for the adsorption of chromium from aqueous solutions. The data for best-fit for linear and non-linear forms of kinetic and isotherm models were compared. Non-linear analysis included error analysis using 'Solver add-in' of Microsoft Excel, Origin and MATLAB software's curve fitting tool. MATLAB and Origin curve fitting tool (R-2 > 0.96) are better than error analysis method (0.790.99) of 'solver add in' for determination of isotherm parameters. Adsorption of chromium on nanoalumina is best explained by Langmuir isotherm model. Linear method is better than non-linear methods to determine the kinetic model. The sum of the square of error among linear and non-linear analysis methods for kinetic models is minimum for linear analysis method (0.008) than all other non-linear analysis methods (0.019-0.478). The adsorption of chromium on nanoalumina is governed by pseudo-second-order kinetics. (C) 2016 Elsevier B.V. All rights reserved.