The kinetic data were fitted to a simple model, the pseudo-first-order which describes the hydrogen peroxide decomposition.
It is found that the flux increases when one of the parameters defining the diffusion model, the pseudo-diffusivity, is increasing or when the other parameter defining the diffusion, the order of fractional differentiation, is decreasing.
In standard black-oil model, the pseudo-components are usually defined as phases at standard conditions.
The result indicated that, compared with the pseudo-second-order model, the pseudo-first-order model provided a better correlation for the adsorption of dyes on Tb-RGO.
The second model, the pseudo-second-order reaction, is dependent on the amount of solute adsorbed on the surface of the adsorbent and the amount adsorbed at equilibrium.
The pseudo first-order model: The pseudo-first order equation representing the curve of log(Qt − Qe) versus time could be written as shown in Eq. (12): Logleft( {Q_{e} - Q_{t} } right) = Logleft( {Q_{e} } right) - frac{kt}{2.303} (12)where Qt is the amount of arsenic adsorbed at time t in mg/g, Qe is the amount of arsenic adsorbed at equilibrium (mg/g), and k is the initial adsorption rate (min−1).
Although the full model without the Distance to TSS variable is a substantial improvement on the empty model, the pseudo-r suggests much variance remains unexplained.
Four kinetic models, the pseudo first- and second-order equations, the Elovich equation and the intraparticle diffusion equation, were selected to follow the adsorption process.
Among the kinetic models, the pseudo – second – order model was superior to others and among the adsorption isotherms, Langmuir model fits well as compared to that of Freundlich model based on the regression coefficient values.
With the additional entry of within-person time parameters, residual variance fell to 16.06 in both saturated and spline models; the pseudo R rose to 48.3% for both saturated and spline models.
