Trisodium Dicarboxymethyl Alaninate (MGDA-3Na)

Synonyms: Methylglycinediacetic acid trisodium salt; Trisodium methylglycinediacetate; Trisodium 2-methylnitrilotriacetate; N,N-Dicarboxymethyl alanine trisodium salt; N,N-Bis(carboxymethyl)alanine trisodium salt; DL-Alanine-ChemicalbookN,N-diacetic acid trisodium salt; N-(1-Carboxyethyl)iminodiacetic acid trisodium salt hydrate; N,N-Bis(carboxymethyl)-DL-alanine trisodium salt; N-(1-Carboxyethyl)iminodiacetic acid trisodium salt hydrate

Molecular formula: C7H8NNa3O6

Appearance: Light yellow liquid

Content: 40%

CAS NO: 164462-16-2

pH: 10-12

Molecular weight: 271.11

Density: 1.31 g/cm3 (20°C)

Viscosity: 25 mPa·s (23°C)

Active content: 40%

Non-toxic, non-irritating to eyes and skin

Applicable pH range (2–13.5)

Uses:

As a green chelating agent, trisodium dicarboxymethyl alaninate (MGDA-3Na) offers excellent toxicological safety and stable biodegradability. MGDA is a metal ion chelator capable of forming stable soluble complexes with metal ions. Na3 can be widely used across a broad pH range and exhibits synergistic effects with bactericides. Na3 can serve as a substitute for chelating agents such as phosphates, NTA, EDTA, and citrates in detergents. In terms of detergency performance, trisodium dicarboxymethyl alaninate (MGDA) acts as a stabilizer for sodium perborate and sodium percarbonate, making it an effective builder in phosphate-free detergent formulations. MGDA has been proven to deliver high-efficiency bleaching and removal of stubborn stains in commercial phosphate-free dishwasher formulations. MGDA demonstrates outstanding cleaning performance in high-efficiency laundry powders, liquid detergents, and soap-based cleaners (e.g., soaps). Adding MGDA to various soaps helps prevent rancidity, discoloration, and dirt deposition. MGDA functions as a descaling and anti-scaling agent, preventing scale formation and softening water. It also breaks down metal salts and hydroxides to remove insoluble salt deposits in various industries.

Applications:

MGDA-3Na is biodegradable and enhances the cleaning effectiveness of household and industrial detergents and cleaners.

Fabric Detergents: In heavy-duty laundry powders, liquid detergents, and soap-based cleaners, MGDA exhibits excellent cleaning power, particularly for stubborn stains such as natural oils, sebum, blood, milk, ink, dust, and proteins.

In detergents containing fatty acids and soaps, soap scum easily forms with calcium and magnesium ions in water, depositing on fabric surfaces and leading to rancid odors and reduced wettability. MGDA effectively addresses calcium soap stains and prevents their redeposition.

Automatic Dishwashing Detergents: Phosphorus-containing builders were once widely used in automatic dishwashing detergent formulations. Since the implementation of phosphorus restrictions in various countries, numerous phosphorus-free alternatives have emerged. However, phosphorus-free formulations often result in reduced film prevention and stain removal performance. MGDA helps narrow this performance gap.

For stubborn stains such as starch and proteins in food, MGDA has been proven to deliver efficient rinsing and starch stain removal in commercial phosphorus-free dishwashing detergent formulations, particularly effective against tea stains.

Cleaning of Inorganic Deposits: MGDA can convert insoluble compounds into water-soluble substances, demonstrating good dissolution performance for inorganic deposits. For aged, dry calcium stains, soaking with 1g/L MGDA yields better results.

In many cleaning scenarios, such as removing calcium carbonate scale, dissolving these deposits requires shifting the equilibrium reaction of calcium carbonate formation toward soluble ions. This can be achieved by removing carbonate ions or calcium ions. The former method involves adding acids (e.g., hydrochloric acid, citric acid) to generate carbon dioxide, but it is unsuitable for closed systems or corrosion-prone environments. The latter method utilizes chelating agents like MGDA to form soluble complexes, also preventing new calcium carbonate scale formation.

Another example is cleaning calcium phosphate scale in the dairy industry. Milk contains significant amounts of calcium phosphate, which forms insoluble deposits during processing that are difficult to clean. EDTA is commonly used to address this, but its biodegradability is uncertain. MGDA can serve as an alternative to EDTA; although its chelation performance is inferior to EDTA, it surpasses other biodegradable chelating agents.