An Alternative Radiation Shielding Material Based on Barium-Sulphate (BaSO₄)-Modified Fly Ash Geopolymers

Geopolymers are a new environmentally friendly cementitious material, and the application of geopolymers can reduce the carbon dioxide emissions caused by the development of the cement industry.

This study investigates the radiation shielding capacity of fly ash geopolymers (FAGP) as a viable alternative to conventionally used ordinary Portland cement (OPC) due to the high demand for an environmentally friendly, cost-effective and non-toxic shield material.

The FAGP material was fabricated and combined with Barium sulphate (BaSO₄) at different ratios (0, 5, 10 and 15%). Different thicknesses (3, 6 and 9 cm) of the samples were also prepared. An energy-dispersive X-ray (EDX) was used to determine the elemental percentages of the materials, which were then used to calculate their effective atomic number (Z_eff). An ion chamber was used to detect the dose of radiation transmitted through the samples.

The lowest radiation dosage (34.68 µGy) and highest Z_eff were achieved with FAGP combined with 15% BaSO₄ at 9 cm thickness. The decrease in radiation dosage can be attributed to the increase in Z_eff with the addition of BaSO₄ to FAGP, which in turn increases the density of FAGP.

Thus, the radiation dose can be significantly reduced with a higher ratio of BaSO₄ to FAGP. This study shows that FAGP combined with BaSO₄ is a promising radiation shielding material, as well as a viable alternative to OPC.