Numerous studies have analyzed the parent material of soils and concluded that the elements such as Al, Mn, Ni and Cr in the soil are mainly derived from the processes of weathering and metamorphism in nature. The enrichment of different elements may be due to the change of the parent material geologic age Al and Mn are considered to come from the oldest geological rocks such as the Paleozoic and Mesozoic. Ni and Cr come from the geological areas such as loose sediments of the Pliocene. The distribution of heavy metals such as Pb, Hg and Cd is mostly related to human activities. With the rapid development of urbanization and industrialization, the "three wastes" emitted by industrial and mining enterprises such as mining and metallurgy, the combustion of fossil fuels such as coal and oil, and the excessive application of pesticides and fertilizers, heavy metals enter the soil through various channels. Because heavy metals can not be degraded by microorganisms and are hard to eliminate, their accumulation in the soil to a certain extent causes soil-plant system toxicity, resulting in degradation of soil quality, reduction of crop yield and quality, deterioration of the hydrological environment, Magnification level, and thus endanger human health. At present, the common domestic and international soil heavy metal management methods are mainly physical, chemical and biological methods, and for the treatment of heavy metal pollution of soil, ideas have been completely removed from heavy metals to implement a risk-based control strategy. The chemical passivation repair technique is adopted to change the occurrence patterns of heavy metals in the soil by adding a passivating agent to the heavy metal contaminated soil. The main purpose is to change the heavy metals from highly bioequivalent exchangeable and carbonate-bound It is one of the effective ways to control the heavy metal contaminated soil that the low bioavailability of organic bound and residual state is transformed and its bioavailability is reduced. The technology has the advantages of short processing time, low cost and wide application range. The main types of commonly used chemical passivation agents are inorganic, organic, micro-organisms and new composite materials. Inorganic passivators mainly include clay minerals (sepiolite, zeolite, bentonite, kaolin, etc.), industrial by-products (fly ash, fly ash, lime, red mud, silica fume, gypsum, etc.), phosphates and metal oxides (Superphosphate, phosphate rock, calcium magnesium phosphate, hydroxyapatite, phosphate, magnesium oxide, etc.) and other industrial and agricultural waste (peat, slag, cement, etc.); organic passivators mainly include animals Manure, straw, biochar, black carbon, municipal sludge, etc. Microbial passivators mainly include mycorrhizae and reducing bacteria. The new composite materials mainly include modified material, inorganic-organic material and nanomaterials. Due to the complexity of soil inherent matrix and the pollution of most heavy metals in soils with heavy metals, the complex interaction exists between heavy metals and heavy metals and soil interface. Therefore, different types of soil for the selection of different heavy metals passivation agent to repair its passivation effect is not the same. However, at present, most of the researches only focus on the repair of some heavy metals, and there are few reports on simultaneous simultaneous passivation and simultaneous restoration of multiple heavy metal contaminated soils. Heavy metals and passivators in the soil adsorption, complexation and coprecipitation and other physical and chemical reactions to regulate and change the existing forms of heavy metals in the soil, mainly to reduce the bioavailability of heavy metals, thereby reducing the heavy metals on plants and humans Other biological receptors such as toxicity, to repair the purpose of contaminated soil. In general, the bioavailability of different forms of heavy metals is also large and closely related to each other, and the relationship between heavy metal forms and bioavailability is generally expressed as exchangeable> carbonate-bound> Fe-Mn oxides Binding state> Binding state> Residue state. The bioavailability of heavy metals mainly refers to the part that plants can absorb and utilize. Compared with the graded forms of heavy metals, exchangeable and carbonate bounds are the most effective, followed by iron and manganese oxides, The organic bound state is less effective, while the residue state is almost ineffective for the plant. At the concentration of 20%, palygorskite, steel slag and phosphate rock powder can significantly reduce the bioavailability of five heavy metals Pb, Cu, Zn, Cd and As in the soil. Passivator allows plants to be easily absorbed exchangeable and carbonate bound reduced, leaving the refractory residue state increased. 20% of phosphate rock powder can significantly increase the residual Pb, Cu, Zn and Ca type arsenic, so that the exchangeable Cd and Zn and carbonate bound Zn significantly decreased; 20% steel slag exchangeable exchangeable Cd, Zn and Iron arsenic decreased significantly, so that the residual Cu and Zn significantly increased; 20% palygorskite residue state Pb, Zn significantly increased exchangeable Pb, Cd significantly decreased. Of the four passivators, charcoal and palygorskite have larger specific surface area and pore volume, and they are mainly adsorbed and surface-complexed on the passivator of heavy metals. Although the specific surface area and pore volume of slag and phosphate rock are small, , But with a higher pH, the mechanism of passivation of heavy metals to chemical precipitation. 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