where C0 is the initial CR concentration, Ct is the CR concentrations
(mg L−1) at any time, V is the volume of solution (L) and
m is the mass of the activated carbon (g). Due to the inherent
bias resulting from the linearization of the isotherm models,
the non-linear regression Root Mean Square Error (RMSE) (Eq.
(A2)), the Sun of Error Squares (SSE) Eq. (A4) and Chi-squares
(2) Eq. (A4) test are employed as criterion for the quality of
fitting (El-Sheikh et al., 2004).