摘要
The chemical stability of simulated waste forms Zr_(1–x)Nd_xSiO_(4–x/2) was investigated using the static leach test(MCC-1) with lixiviants of three pH values(pH=4, 6.7 and 10) at three temperature points(40, 90 and 150 oC) for periods ranging from 1 to 42 d, and the influence of temperature, pH, as well as their combined effects were explored in detail. The results showed that all the normalized release rate of Nd firstly decreased with leaching time and closed to equilibrium after 14 d. As the temperature increased, the normalized release rate of Nd also increased, but it was no more than 3×10^(–5) g/(m^2·d). And, the normalized release rate of Nd reached the highest values(~5×10^(–5) g/(m^2·d)) when pH=4, whilst the normalized release rate of Nd remained the lowest value(~1×10^(–5) g/(m^2·d)) near neutral environment(pH=6.7).
The chemical stability of simulated waste forms Zr_(1–x)Nd_xSiO_(4–x/2) was investigated using the static leach test(MCC-1) with lixiviants of three pH values(pH=4, 6.7 and 10) at three temperature points(40, 90 and 150 oC) for periods ranging from 1 to 42 d, and the influence of temperature, pH, as well as their combined effects were explored in detail. The results showed that all the normalized release rate of Nd firstly decreased with leaching time and closed to equilibrium after 14 d. As the temperature increased, the normalized release rate of Nd also increased, but it was no more than 3×10^(–5) g/(m^2·d). And, the normalized release rate of Nd reached the highest values(~5×10^(–5) g/(m^2·d)) when pH=4, whilst the normalized release rate of Nd remained the lowest value(~1×10^(–5) g/(m^2·d)) near neutral environment(pH=6.7).
基金
Project supported by the National Natural Science Foundation of China(41302028,41302029,21507105)
Thousand Youth Talents Plan(Y42H831301)
Key Project of Sichuan Education Department(14ZA0099,15ZB0116)
Foundation of Laboratory of National Defense Key Discipline for Nuclear Waste and Environmental Safety,Southwest University of Science and Technology(15yyhk10)
the Doctor Foundation in Southwest University of Science and Technology(10zx7126)
Hebei Science and Technology Support Program(15211121)