NTA is an organic compound with the chemical formula C6H9NO6. It is a white crystalline powder that is slightly soluble in hot water and soluble in ammonia and sodium hydroxide solutions. It is mainly used as a chelating agent, catalyst, stabilizer, descaling agent, electroplating agent, color photographic developer, and polycarboxylate chelating agent.
Physical and chemical properties
Appearance and Characteristics White Powder Density 1.61g/cm3
Production method
1.Chloroacetic acid reacts with sodium hydroxide to produce sodium chloroacetate, followed by ammonium chloride reaction to produce aminotriacetate, which is then acidified to obtain the final product. The chloroacetic acid process is outdated and costly, and has been phased out abroad. Manufacturers in the United States and Japan that produce a large amount of by-product HCN use the Streeg method. Pure liquid HCN and formaldehyde react with ammonia or amine salts under acidic conditions to produce nitrogen triacetonitrile, which is then hydrolyzed to obtain NTA. The investment and operational costs of this law are high, and the safety is poor. Another method is the carboxymethylation method successfully developed abroad in the 1970s. This method uses NaCN, which is convenient for storage and transportation. The reaction is carried out under alkaline conditions, without producing volatile HCN, and has good production safety.
2.Chloroacetic acid reacts with sodium hydroxide to produce sodium chloroacetate, which then reacts with ammonium chloride to produce sodium aminotriacetate. The final product is obtained by acidification.
3.Dissolve glycine and iodoacetic acid in water, heat with potassium hydroxide solution to 80 ℃, cool, and then acidify with hydrochloric acid to precipitate the iminotriacetic acid. Recrystallize in hot water to obtain the pure product.
4. Put 885kg of monochloroacetic acid into an acid resistant kettle, stir and heat to 64 ℃. After complete melting, add 1220kg of 30% liquid alkali dropwise for neutralization reaction. React at 80-90 ℃ for 5-6 hours. Obtain an aqueous solution of sodium chloroacetate. Send the neutralizing solution into a thin film evaporator and concentrate it under vacuum. When approaching saturation, pour in condensation corrosion, heat to 60 ℃, and adjust the pH value to 7-8 with a saturated solution of sodium carbonate. Continue to heat up to 80 ℃ and add 400kg of saturated ammonium chloride solution while stirring. After adding, stir for another 5 minutes and mix evenly. Adjust the pH value to 9-10 with liquid alkali. Stop the reaction. Let it stand for 4 hours. Filter. Collect the filtrate. Pour the filtrate into the acidification kettle, add hydrochloric acid for acidification, and stop adding acid when the pH value reaches 0.5-1.2. Cool and let stand, crystallize. Suck out the upper liquid, wash the crystals several times with water, and dry to obtain the finished product.
Purpose
1.It is a well-known chelating agent that can form metal complexes with various metals for analysis, determination, and separation of rare metals. It can also be used to extract individual metals from rare metals.
2.Catalyst In the production of polyurethane foam plastics, it can be used as a foaming catalyst, which can immediately foam and quickly gel.
3.Stabilizers can be used as stabilizers in polystyrene production.
4.In the steam generator system of a nuclear reactor, a descaling agent can be injected as an aqueous solution into the steam water cycle to remove scale and corrosive substances between the walls, without affecting efficiency during the addition process.
5.Electroplating agents can accelerate the deposition rate in non-toxic electroplating.
6.Color photographic developer is one of the important components in color photographic development, which can be used to prevent sedimentation during development. Nitrotriacetic acid, as a substitute for triphosphate, has also received attention in solving the problem of eutrophication of water bodies caused by synthetic detergents.
7.Nitrile triacetic acid is an organic polycarboxylate chelating agent that, due to its small molecule size, can chelate more metals and has strong biodegradability. Adding a certain amount of reducing agent and pH regulator to nitrilotriacetic acid can effectively remove Fe2O3 and hematite oxide.
8.Used as an analytical reagent, such as a titrant or masking agent. It is also used for color development, printing and dyeing, and non-toxic electroplating.
9. It is widely used as a metal ion chelating agent in industries such as textiles and papermaking.