Highly reactive fission product cesium may volatilize at high temperatures. PbO–B 2 O 3 –ZnO glass with low melting temperature and excellent chemical durability can be used as a potential matrix for immobilizing Cs. In this work, five PbO–B 2 O 3 –ZnO glasses with different contents of Pb were synthesized via a melt-quenching process. These specimens were characterized with XRD , Raman, DTA and viscosity measurements . The results showed that the melting temperature decreases, viscosity decreases and structural polymerization increases with increasing lead content. Cs-doped 35PbO–60B 2 O 3 –5ZnO glasses were synthesized at low temperatures. XRD results revealed the amorphous nature of the glass solidified bodies. EDS and ICP-MS studies confirmed that Cs is retained in the glass. Clear vitrified waste products containing up to 13.6 wt% Cs were obtained. The chemical durability of the samples was evaluated via PCT-A and MCC-1 method. For the glass solidified body comprising a Cs/matrix ratio of 0.136, the leaching rate of Cs was 1.6 × 10 −1 g m −2 d −1 from the PCT test, which indicates that it has a good chemical stability. 35PbO–60B 2 O 3 –5ZnO glass was expected to be a suitable matrix for Cs immobilization.
This study mainly investigated the Bi 2 O 3 -B 2 O 3 -ZnO ternary glass to immobilize the iodine waste forms under low sintering temperatures (≤600 °C). Based on the results of Molecular Dynamic (MD) code GULP and amorphous fraction, the Bi 2 O 3 -B 2 O 3 -ZnO ternary glass with 20 mol% Bi 2 O 3 to be chosen to immobilize the sliver-coated silica gel with 10 wt%, 20 wt% and 30 wt% iodine loadings (total content of iodine is 8 wt%). The results show that the amorphous fraction are increased with temperature rising and the composition has dominant effect on determining the density results. The specimen with 20 wt% sintered at 600 °C has the highest amorphous fraction as 0.71. The SEM-EDS results reveal that part of iodine had been physically solidified in the form of white spots and the rest chemically solidified in the glassy phase. Our findings demonstrate the potential of Bi 2 O 3 -B 2 O 3 -ZnO ternary glass to immobilize iodine waste forms.
危险品化学品经营许可证（带存储）