In the Fig. – (a) And (b) the EDX analysis of the parent Y11 and modified MY12 zeolites have been …show more content…
An adsorption equilibrium usually named adsorption isotherm. It shows how an adsorbate interacts with adsorbent surface and also the amount of tendency of adsorbate to adsorbent will be understood. An adsorption isotherm consists of some constants which values express the surface properties and affinity of the adsorbent (عینا). It can also be used to find the adsorption capacity of adsorbent. At equilibrium the concentration will remain constant (CEJ). By plotting the solid-phase concentration versus liquid-phase concentration the adsorption isotherm achieve whereby certain constants will be attained containing various information about the surface properties and affinity of the adsorbent. …show more content…
As can be seen in the table— from the Langmuir isotherm, the maximum adsorption capacity (qm) for usual zeolite Y is about 15 mg/g. After modification of parent zeolite its value was reached to remarkable amount of 133 mg/g. The essential characteristics of the Langmuir isotherm can be expressed in term of the dimensionless constant separation factor, RL, is as follow:(MW).
R_L=1/(1+K_L C_0 )
Where C0 is the initial concentration and KL is the Langmuir isotherm constant. The RL values reflect the property of adsorption; RL > 1 is unfavorable, RL=1 is linear, 0 < 1/n <1) indicative of a higher adsorb ability of MB for both adsorbents  (CEJ).
As can be seen in the table ---, the Redlich–Peterson g parameter is almost 0.95 for both adsorbent which is near 1and imply that this isotherm is approaching to Langmuir isotherm [رفرنس].
The Temkin parameters A and B were also listed in Table ---. From Y11 to modified MY12, the values of A and B became larger. This issue also confirms the promotive characteristic of the hierarchical modified MY12 zeolite.