Effect of fluorine on stabilization/solidification of radioactive fluoride liquid waste in magnesium potassium phosphate cement

This paper investigated the effect of fluorine mass fraction on magnesium potassium phosphate cement (MKPC) stabilization/solidification (S/S). The solidified object was a simulated fluid containing Co2+, Sr2+, Cs+ and F-. The results showed when the fluorine mass fraction increased, the setting time of the MKPC slurry extended. Under the same conditions, the 28-day compressive strength of the MKPC solidified forms reduced, and the freeze-thaw resistance enhanced. When the fluorine mass fraction was more than 6 wt%, a new product (MgF2) appeared and caused the structure to become evacuated. Meanwhile, leaching concentration of the researched ions increased, especially Cs2+ and F-. When the fluorine mass fraction of the MKPC solidified forms was 12wt%, a very small amount of wagnerite was observed.