Chelating agent is a chemical substance with chelating effect that can form stable complexes with metal ions. The following is a common chelating agent EDTA (ethylene diamine tetraacetic acid) formula:
Raw materials:
Ethylenediamine (dimethylamine): 50 grams
Sodium bicarbonate: 200 grams
Sodium hydroxide: 200 grams
Anhydrous ethanol: 1000 milliliters
Anhydrous ether: 200 milliliters
Hydrochloric acid: 10 milliliters
Water: moderate amount
Preparation process:
(1) Add ethylenediamine to 1000 milliliters of anhydrous ethanol and stir until completely dissolved.
(2) Under continuous stirring, add sodium bicarbonate and sodium hydroxide until completely dissolved.
(3) Add hydrochloric acid to anhydrous ether and add it to the reaction solution. At the same time, add an appropriate amount of water to control the reaction temperature between 40 and 45 ℃.
(4) After about 60 minutes of reaction, stop heating and cool to room temperature.
(5) Filter out the reaction solution, collect the solids, and wash them thoroughly.
(6) Dry the solid in an oven to constant weight to obtain EDTA product.
It should be noted that the preparation of chelating agents requires following safe operating procedures to ensure the safety of operators and the environment. Meanwhile, different types of chelating agents have different formulations and preparation methods, so appropriate adjustments and optimizations should be made according to specific needs in the laboratory or industrial production process.