Assessment on linear and non-linear analysis for the estimation of pseudo-second-order kinetic parameters for removal of dye using graphene nanosheet

Graphene nanosheets were used as adsorbent for the removal of crystal violet dye from its aqueous solution. The equilibrium kinetic data were analyzed using pseudo-second-order kinetic model. A comparison between linear and non-linear methods of estimating the kinetic parameters was examined. Four pseudo-second-order kinetic linear equations have been discussed here. The coefficient of determination test were employed as methods of error analysis for determining the best-fitting equation. The results revealed that the non-linear method proved to be a significantly better alternative for obtaining the kinetic parameters in comparison with the linear form of the model. In addition, the (chi(2)) test was found to be a better method for determination of the best-fitting model.