Transmutation of ¹²⁹I Containing Nuclear Waste by Proton Bombardment

As a long-lived nuclear waste, iodine (¹²⁹I) which is primarily generated from nuclear fission of uranium or plutonium is considered harmful to human and environment. Therefore, proper steps are required to treat the radioactive isotope. In this work, we propose transmutation of I-129 isotope using cyclotron-based proton bombardment. The TALYS code was employed to calculate nuclear cross-sections of various nuclear reactions possible to transmute I-129 into shortlived radionuclides or stable isotopes. Twelve different nuclear reactions, namely (p,n), (p,2n), (p,3n), (p,np), (p,2np), (p,a), (p,d), (p,2p), (p,nα), (p,γ), (p,³He), and (p,t), which have significant cross-sections (greater than 1 mb) were analyzed. Based on the nuclear reactions, there were 6 possible stable isotopes produced from proton bombardment of ¹²⁹I, such as ¹²⁹Xe, ¹²⁸Xe, ¹²⁷I, ¹²⁶Te, ¹²⁵Te and ¹³⁰Xe. Short-lived radionuclides such as ^29mXe (half life = 8.88 days), ¹²⁷Xe (half life = 36.35 days), ^127mXe (half life = 62.9 seconds), ¹²⁸I (half life = 24.99 minutes), ^125mTe (half life = 57.40 days), ¹²⁷Te (half life = 9.35 hours) and ^127mTe (half life = 106.1 days) could also be possibly produced from the proton irradiation of ¹²⁹I nuclear waste. To sum up, the longest radionuclide could be generated from proton bombardment of ¹²⁹I nuclear waste is ^127mTe (half life = 106.1 days), which is a lot shorter than ¹²⁹I (half life = 1.57x10⁷ years). This theoretical study indicates that transmutation of ¹²⁹I nuclear waste by proton bombardment into short-lived radionuclides is greatly feasible. Current available cyclotrons in Indonesia may be employed to help transmute ¹²⁹I into short-lived radionuclides or stable isotopes. This theoretical study can be used as a reference for future ¹²⁹I nuclear waste if proton beams are employed in the transmutation.