The removal of radioactive cesium element (Cs-137) from wastewater is relatively challenging due to its high diffusion coefficient, short hydration radius, and the similarity between its chemical behavior to other alkali metals having high background concentrations, leading to a competition that reduces the removal efficiency of cesium (Cs-137). This study introduces an innovative treatment process using a submerged membrane adsorption hybrid system (SMAHS) using natural Iraqi clay minerals as adsorbents. The operational conditions were studied using the (SMAHS) continuous flow operation in stirred filtration mode experiments. The maximum operational conditions were achieved for the initial radioactivity concentration of Cs-137 at 7201.8 Bq/L, clay dose 1 g/L, the stirring speed at 700 rpm, pH =6, the transmembrane pressure (TMP) under 2 bar, and temperature at 25 °C. The SMAHS rejection percentage of Cs-137 was 93.6 % and the permeate flux was 105.6 L/m2.h at the best operational conditions. This study demonstrates that utilizing raw bentonite which is both environmentally friendly and locally available as an adsorbent in the SMAHS has proven its effectiveness for removing Cs-137 from wastewater. The hybrid method effectively immobilizes radioactive waste by converting it from liquid to solid state, leading to an extended and safer storage time.
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