Yq. Zhang et al., Selective separation behavior of silica gel for zirconium in simulated high level radioactive liquid waste, J RAD NUCL, 247(1), 2001, pp. 205-208
Zirconium in simulated high lever radioactive liquid waste (HLLW) was selec
tively adsorbed and separated by self-made high adsorption activity silica
gel. The selective adsorption mechanism was analyzed according to the struc
ture character of self-made silica gel and performance of zirconium in acid
simulated HLLW. The results show that the adsorption selectivity of self-m
ade silica gel for zirconium is strong, because zirconium has higher positi
ve charge and zirconium ion hydrolyzes easily. Distribution coefficient of
self-made silica gels for zirconium is 53.5 ml/g. There are 6.5 (OH)/nm(2)
on the surface on self-made silica gels which provide more adsorption activ
ity places, thus self-made silica gels have higher adsorption capacity for
zirconium (31.4 mg/g). The elution rate of the adsorption of zirconium on s
elf-made silica gel by 0.2 mol/l H2C2O4 is more than 99%. The solubility of
the self-made silica gel in nitric acid is low, the chemical stability of
self-made silica gel is very strong.