A preliminary study of two different clays for separation of some artificial radionuclides in stimulated waste

Abstract EN

The removal of long lived radionuclides, such as 134Cs(I),133Ba(II),90Sr(II) and152Eu(III) by bentonite (W-Bent) and kaolin (S-Kaol) was studied as a function of different parameters using a batch technique.

The results showed that the optimum pH was selected to be 6.

Kinetically in case of W-Bent, the adsorption is heterogeneous for 134Cs,133Ba and homogenous for 90Sr and 152Eu.

The distribution coefficient values follow the order of 152Eu˃134Cs˃90Sr˃133Ba.

Langmuir, Freundlish, Dubinin-Raduskevich (D-R) and Temkin isotherm models were applied.

According to the D-R model, W-Bent showed a high affinity to 152Eu with a maximum capacity (qm= 0.43 mol/Kg) in comparison with S-Kaol (qm=0.023 mol/Kg).

Also according to D-R model the adsorption energy (E˃ 8.0 KJ mol-1) that means the adsorption reaction is expected to be chemisorption.

Finally both clays are cost–effective sorbent materials with an excellent adsorption capacity, but some surface modification for S-Kaol is recommended to be more effective than its natural form.