Barite is a non-metallic mineral primarily composed of barium sulfate. It has a high density (4.3~4.5g/cm³) and relatively low Mohs hardness (3~3.5). It exhibits stable chemical properties, is insoluble in water and hydrochloric acid, non-toxic, non-magnetic, and has the ability to absorb X-rays and gamma rays.
1. Advantages of Barium Element Compounds in Radiation Shielding:
①Barium is positioned ahead of lead in the periodic table, and it is a non-radioactive element. It possesses a relatively high atomic mass, making it more likely to undergo the photoelectric effect when interacting with radiation, which is highly beneficial for preventing ionizing radiation. Additionally, barium ions have a high dielectric constant and strong magnetization, resulting in excellent magnetic loss properties when dealing with non-ionizing radiation. In comparison to some other radiation shielding materials (such as early lead-based X-ray shielding), barium has distinct advantages due to its superior performance and the avoidance of toxic lead oxide-related issues.
②Radiation shielding cements typically include barium cement and strontium cement. While strontium cement offers better protection against ionizing radiation, barium cement excels in shielding gamma rays and X-rays. Additionally, when used as additives in composite fiberboard materials, barite powder, zeolite powder, and magnetite powder all demonstrate some level of electromagnetic shielding effectiveness. Overall, in the low-frequency range (below 110 kHz), barite powder proves to be the most effective in electromagnetic shielding, achieving a shielding effectiveness of 17.99 dB. Zeolite powder follows with 17.71 dB, and magnetite powder provides slightly lower effectiveness at 16.99 dB. Therefore, barite powder stands out as the most superior option for electromagnetic shielding.
2. Research status of global Barite radiation protection application:
①Early, the Akkur research group of Demirel University in Turkey used barite as coarse and fine aggregate, and prepared three different types of barite concrete through different ratios, and the test results showed that barite as an aggregate showed excellent performance in shielding gamma rays.
②In addition, Günther et al. used the absorption properties of barium sulfate, barium titanate, and bismuth oxide to develop a composite fiber that can absorb X-rays. They made this fiber into yarns and fabrics, and succeeded in achieving efficient shielding against X-rays.
③Japan also proposed an innovative method, adding barium sulfate to viscose solution for spinning, and developed a new type of fiber. The X-ray shielding effect of the fabric made of this fiber is obvious, especially for 6kV and 2mA cathode X-ray sources, the shielding efficiency is as high as 97%.
3. Summary:
①The reason why barite can be used for radiation protection is that its main component is barium sulfate, in which barium has a high-quality nucleus, containing many atoms per unit volume, which increases the probability of photoelectric effect and other phenomena, so that it is easier to absorb the energy of rays. In addition, barium ion also has a high dielectric constant and strong magnetization characteristics, which makes it show excellent magnetic loss in the resistance to electromagnetic radiation.
②At present, the application of barite in radiation protection is mainly concrete materials in the construction industry, additives in medical protective clothing, and coatings as electronic signal shielding materials.