The invention belongs to the technical field of heavy
metal pollution soil restoration, and particularly relates to a soil heavy
metal passivator, a preparation method thereof, and a
passivation method thereof on
soil cadmium. The soil heavy
metal passivator provided by the invention is prepared from the following materials in parts by weight: 30 to 50 parts of modified alkali minerals, 10 to 15 parts of rotten
agriculture and
forestry wastes, 1 to 10 parts of soil conditioners, 1 to 5 parts of pH sensitive gel, 1 to 5 parts of
phosphogypsum, and 0.1 to 5 parts of
graphene. The soil heavy metal passivator provided by the invention has stronger adsorbing and chelating functions, can effectively fix heavy metal
cadmium in the soil, and prevents effective
cadmium from entering into crops; regulation can be carried out according to the
soil pH, so that the utilization ratio and the long-term stability of the soil heavy metal passivator are improved; meanwhile, with an added
soil conditioner, the soil environment can be improved, and the
soil fertility is improved. The passivator provided by the invention can better meet the urgent demand of heavy
metal pollution soil restoration in China currently on strong stability, no secondary
pollution, and durable and stable effect.