A soil cadmium passivator, a preparation method and application thereof

Abstract

This invention discloses a soil cadmium passivating agent, its preparation method, and its application, belonging to the field of soil heavy metal pollution remediation technology. The preparation method includes the following steps: screening and removing impurities from calcium-phosphorus-silicon industrial waste residue, crushing and sieving to obtain pretreated calcium-phosphorus-silicon industrial waste residue; mixing the pretreated calcium-phosphorus-silicon industrial waste residue with residual raffinate and adjusting the solid-liquid ratio, stirring and acid-hydrolyzing to obtain a slurry; drying the slurry to constant weight and crushing to obtain the soil cadmium passivating agent. This invention also discloses the soil cadmium passivating agent prepared by the above method and its application. This invention uses three phosphorus chemical solid wastes—phosphorus tailings, yellow phosphorus slag, and residual raffinate—as raw materials, selecting and proportioning them, and preparing the soil cadmium passivating agent through acid hydrolysis activation and low-temperature drying and shaping. This solves the problems of poor passivation effect, poor stability, and long preparation cycle of existing passivating agents, and has good practical value.

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