Silica Fume Effect on Retention Characteristics of Portland Cement for Uranium(Ⅵ)

With simulated groundwater as leachant,the retention capabilities of the portland cement,which contains different amount of silica fume,are investigated under 25 ℃ and 42 days.The results indicate that silica fume can improve the retention capabilities of portland cement for uranium.When the cement contains 15% silica fume,the diffusion coefficient is 7×10~(-3) cm~3·d~(-1).It is only 5.5% of the cement without containing fume.