AR18 dye removal by the use of ACWand ACP followed pseudo-second order
equation R2 N 0.99 and pseudo-first-order equation R2 N 0.975 respectively.
Due to the general porosity of the ACW and ACP, intraparticle
diffusion would be expected in the adsorption processes. This
could be represented into three adsorption steps: (i) instantaneous
AR18 adsorption within the first few minutes of the contact time, (ii)
equilibrium will be gradually reached as the active sites of adsorption
are being used (iii) reaching to the equilibrium stage [59].