Introducing Micro Flowerlike Bismuth Sulfide for Iodate Anion Removal

There are strong radiological hazards and the risk of direct cell damage in living organisms for radioactive iodate (131IO3–/129IO3–). Thus, it is essential to capture and remove them. In the contribution, the micro flower-like Bi2S3 (MF-Bi2S3) was prepared via a hydrothermal method to investigate its adsorption behavior toward IO3–. MF-Bi2S3 exhibits the maximum adsorption capacity of 875.6 mg/g for IO3– at pH ≈ 3, and the adsorbent achieves a removal efficiency of 98.98% within 2 h. Furthermore, the removal efficiency of MF-Bi2S3 can still reach 96.37% at high concentrations of coexisting anions such as Cl–, SO42–, NO3–, and CO32–, demonstrating excellent anti-interference performance. In simulated artificial groundwater, the adsorbent achieves a removal rate of 88.8% for IO3–, suggesting its potential to solve the problem of IO3– in actual wastewater. Notably, the adsorbed products change depending on iodine content, with BiI3O9 and BiOI as the intermediate products, and the final product is BiOIO3. X-ray photoelectron spectroscopy detects the presence of I2 and I3– in the product, which is attributed to the reduction and fixed to iodine by S2–. Meanwhile, the corresponding S2– becomes SO42– and remains in the liquid after the reaction. This work provides a breakthrough solution for effectively removing IO3–.