Method for stabilizing neutralization slag of uranium associated zirconium and zirconia, and stabilization agent used therein

A method for stabilizing a neutralization slag of uranium associated zirconium and zirconia comprising:

• step 1, putting a pretreatment agent into the neutralization slag of uranium associated zirconium and zirconia and stirring evenly for 5-10 minutes (min) to obtain a first mixture;
• adding water with a weight of 15%-25% that of the neutralization slag to the first mixture and stirring for 10-20 min to obtain a mixed mud, and detecting a potential of hydrogen (pH) of the mixed mud;
• wherein the pretreatment agent is a second mixture formed by mixing lime and a nano active material according to a weight ratio of 1:1;
• step 2, maintaining the mixed mud for 30 min and then executing step 3 when the pH of the mixed mud exceeds 8.5;
• otherwise, repeating step 1 until the pH of the mixed mud exceeds 8.5;
• step 3, adding anhydrous calcium chloride into the mixed mud obtained from step 2 and stirring for 10-20 min, sprinkling water on the mixed mud added with the anhydrous calcium chloride to obtain a cemented mud with a moisture content of 15%-25%, and controlling a pH of the cemented mud in a range of 7.5 to 8 and maintaining for 30 min;
• and
• step 4, adding phosphoric acid modified sepiolite and dihydric phosphate into the cemented mud after the maintaining, stirring for 10-20 min and maintaining for 30 min, followed by performing pressure filtering to stabilize the neutralization slag;
• wherein a preparation method of the phosphoric acid modified sepiolite in step 4 comprises:
• adding a sepiolite powder grinded to 200 meshes into a phosphoric acid solution of 5%-10% volume of fraction, wherein a solid-liquid ratio of the sepiolite powder and the phosphoric acid solution is 1:50 gram per milliliter (g/mL);
• stirring the phosphoric acid solution added with the sepiolite powder for 30 min until bubbles completely disappear, followed by aging for 60 min and filtering out a supernatant to obtain a first solid;
• adding the first solid into deionized water, then stirring and dispersing for 20 min to obtain a solution;
• adjusting a pH of the solution to a range of 4 to 5 by using ammonia water to obtain an adjusted solution, standing the adjusted solution for 30 min and filtering out a supernatant of the adjusted solution to obtain a second solid, and drying and refining the second solid to obtain the phosphoric acid modified sepiolite with a 100 mesh sieve.