Radiation attenuation ability of bentonite clay enriched with eggshell as recyclable waste for a physical rradiation barrier

Abstract

Living cells are protected from ionizing radiation by shielding materials such as lead and concrete. This research aims to develop eco-friendly, low-cost, and non-toxic materials for use as physical radiation shielding materials. Bentonite clay and eggshell powder (ESP) were chosen for this study to develop alternative materials that can replace the usage of ordinary concrete in the construction of a physical barrier for radiation shielding. Various samples of bentonite clay concretes were prepared by adding 0%, 25%, 50%, 75%, and 100% of ESP. Four layers consisting of bismuth oxide (Bi2O3), tungsten oxide (WO3), bismuth oxide with graphene oxide (Bi2O3 + GO), and tungsten oxide with graphene oxide (WO3 + GO), loaded in epoxy matrix composites, were developed and added for enhancing concrete blocks' ability to absorb X-rays. PTW Diados with an ionization chamber was used to measure the absorbed dose of the prepared samples at X-ray tube energies of 60, 80, 100, and 120 kVp. The addition of ESP to Bentonite clay samples improved the attenuation ability of clay. The percentage of 75% ESP added to Bentonite clay is the optimum amount to achieve the best attenuation. Also, the addition of the layers significantly enhanced the block samples' ability to attenuate X-rays. On the other hand, the effectiveness of graphene oxide (GO) in increasing the X-ray attenuation capacity of WO3 and Bi2O3 depended on the applied kVp values (adding GO to Bi2O3 resulted in an improvement in Bi2O3 attenuation capacity at 60 and 80 kVp only). As a result, Bentonite clay blocks enriched with ESP and reinforced with Bi2O3, WO3, Bi2O3 +GO or WO3+GO layers are recommended as an effective radiation shielding materials.