The kinetic parameters were determined by the fit of the models with the experimental data through nonlinear regression. The estimation was based on the minimization of the least squares function using the Quasi–Newton method. The calculations were made using the Statistic 9.1 software (Statsoft, USA). The fit quality was measured through the coefficient of determination (R2), sum of squared residues (SSR) and mean squared error (MSE) (El-Khaiary and Malash, 2011; Dotto et al., 2013).