In recent years, the proportion of chelate fertilizers in agricultural products has gradually increased, and its core goal is to improve the absorption and utilization rate of fertilizers. Common chelate fertilizers on the market include chelate iron, chelate zinc, chelate molybdenum, chelate silicon, chelate boron and chelate calcium.
Compared with inorganic micro-fertilizers, chelate fertilizers have many advantages: they are difficult to be fixed in the soil, easily soluble in water, and do not dissociate, thus ensuring that plants can absorb and utilize them efficiently. In addition, it can be mixed with other solid or liquid fertilizers and will not undergo chemical reactions to reduce fertilizer efficiency. However, there are also false chelation phenomena in the market that are falsely advertised by small manufacturers. Next, we will unveil the true face of chelation together.
Chelation, in English, is “chelate”, which comes from the Greek word “chela”, which means the claws of crabs or shrimps. In layman’s terms, chelation refers to the process by which the complex firmly clamps metal ions through its ligands similar to the crab’s double claws. From a professional perspective, chelation essentially refers to the reaction in which the central ion and a specific multidentate ligand are bonded through two or more coordinating atoms to form a complex with a ring structure. It is worth noting that chelation is a special form of complexation. Only when two or more ligands clamp the metal ion like the claws of a crab and construct a ring structure can it be called true chelation.
Chelating agents are widely used in the field of fertilizers, among which EDTA chelating agents are particularly common. EDTA, or ethylenediaminetetraacetic acid, is an organic compound that can form chelates with many metal ions. Its unique chemical structure allows many metal ions with low solubility or even insoluble to exist in a chelate state, thereby increasing their solubility and facilitating crop absorption. Therefore, EDTA chelate fertilizers have been widely used in the agricultural field.
In addition, sugar alcohol chelate fertilizers are also an important type in the field of fertilizers. It is mainly composed of mannitol, sorbitol, xylitol and glycerol mixed with the nutrients required by crops in a specific proportion. This fertilizer is particularly suitable for elements that are difficult to transport in the body, such as sugar alcohol boron and sugar alcohol calcium. Sugar alcohol chelate fertilizer not only carries mineral nutrients in the phloem, but is also a natural component in the phloem sap of plants, which is harmless to plants and humans. Its low molecular weight characteristics make it easy for leaves to absorb it, and then transport nutrients to the plant body. It can be said that sugar alcohol chelate fertilizer is an upgraded version of EDTA chelating agent, with better performance and effect.
With the continuous advancement of science and technology, new chelate fertilizers such as amino acids, citric acid, and polyglutamic acid have gradually entered the agricultural market. As substitutes for EDTA chelate salts, these products have been widely used in water-soluble fertilizers, foliar fertilizers, plant growth regulators, soil conditioners and other fields. They have the advantages of green environmental protection, no residue, good nutrient absorption and low raw material cost, which fits the current “green, organic, and ecological” agricultural development concept and shows huge market potential.
