Characterization and kinetics of low-TENORM zirconium oxychloride production from zircon sand

Zirconium oxychloride (ZOC) is a valuable derivative product of zircon sand processing extensively used in applications such as ceramics, antiperspirants, and electronic components. However, challenges in ZOC synthesis arise from the limited data on the kinetics of critical processes, particularly acid leaching and high radioactivity in the final product. This study addresses these issues by evaluating the kinetics of the leaching process and synthesizing low-TENORM ZOC. The ZOC synthesis involves vital steps, including alkaline fusion, decantation, acid leaching, centrifugation, and crystallization. The results indicated that increasing the temperature and leaching duration improved the recovery, reaching a maximum of 78.06% at 90 °C for 120 min. An ash layer diffusion model best described the leaching process with an apparent activation energy (Ea) of 15.3922 kJ/mol, indicating a diffusion-controlled mechanism. Furthermore, the study successfully synthesized ZOC with alpha and beta radioactivity levels of 0.091 and 0.908 Bq/g, respectively, meeting the regulatory standards for TENORM in Indonesia. These findings provide important insights for improving ZOC synthesis while addressing radioactivity concerns.