The EDTA chelating agent is a complex having a cyclic structure obtained by chelating the chelate ring with two or more ligands with the same metal ion.
Also known as chelation or chelation effect. Chelating ligands (containing two or more ligands with lone pair electron atoms) form two or more coordination bonds with the central ion to form a cyclic compound, i.e., chelate The reaction of. For example, ethylenediaminetetraacetic acid [EDTA, (OOCCH2) 2NCH2CH2N (CH2COO-) can pass through four (sometimes three) carboxylic acid groups and many metal ions such as Fe, Th, Hg, Cu, Ni, Pb and the like Two nitrogen atoms are bonded to form five five-membered chelating rings to produce metal-EDTA chelates with higher stability than the complexes. The chelation of metals in natural water and waste water has a significant effect on the migration, fate or toxicity of heavy metal elements in the environment. On the trace metal ions have a clear reaction, high sensitivity.
Detection of EDTA Chelate Level
If the ligand and silver ions combined, the UV visible area has changed, you can use UV spectroscopy to determine the extent of the reaction; if there is no optical signal changes, you can also use electrochemical means, silver - silver chloride electrode determination of free silver ions Concentration; if it is solid, only the solvent can be used to wash the solid, the free silver ions elute, and then use atomic absorption or other means to detect the silver ion content
A reagent having a polygene ligand capable of chelating with a metal ion to form a chelate. In the water waste water chemistry, organic chelating agents such as aminocarbons (including NTA, ethylenediaminetetraacetic acid, EDTA, etc.), dithizone, 8-hydroxyquinoline, (C12H8N2), sodium potassium tartrate, ammonium citrate and inorganic chelating agents. Chelating agents have high selectivity and sensitivity to various metal ions, and the resulting metal chelates have better stability than similar complexes. In the environmental pollution chemical and chemical industry, often as complexing titrant, metal indicator, metal separation agent, antioxidant, masking agent, to the scale agent, algae agent, flotation agent, fungicide and so on. Especially in water quality analysis, the determination of water hardness, metal ion concentration has been widely used