It was possible to observe that the initial adsorption rate ([alpha]) followed the order MZSF > MZSB, indicating that adsorption on modified zeolite from fly ash was faster than modified zeolite from bottom ash.
The adsorption isotherms of the AO8 on ZFA, MZSF and MZSB are shown in Figures 5 and 6.
As one was expected, the adsorbents originating from fly ash (ZFA and MZSF) exhibited higher maximum adsorption capacity compared to that originating from the bottom ash (MZSB).
It is proposed that multiple mechanisms are involved in the adsorption of the AO8 on ZFA, MZSF and MZSB due to the wide variety of functional groups that its molecules have and surface properties of the adsorbents material.
This study investigated the equilibrium and the dynamics the adsorption of an anionic dye, which is namely Acid Orange 8 dye, AO8, onto unmodified zeolite (ZFA and ZBA) and modified zeolite (MZSF and MZSB) that were synthesized from coal fly and bottom ash, respectively.