Tetraacetylethylenediamine, TAED, N,N,N',N'-Tetraacetylethylenediamine, Tetra Acetyl Ethylene Diamine, TAED Chemical, TAED Bleach Activator, 10543-57-4

Tetraacetylethylenediamine, TAED, N,N,N',N'-Tetraacetylethylenediamine, Tetra Acetyl Ethylene Diamine, TAED Chemical, TAED Bleach Activator, 10543-57-4

Tetraacetylethylenediamine (TAED): A Comprehensive Technical Overview

Tetraacetylethylenediamine, universally known by its acronym TAED, is a pivotal organic compound in the modern chemical industry. It is most renowned for its role as a low-temperature bleach activator in laundry and dishwashing detergents, revolutionizing cleaning processes by enabling energy efficiency and enhanced stain removal. This document provides an exhaustive look into its chemical profile, mechanism of action, applications, environmental safety, and market availability.

1. Chemical and Physical Profile

TAED is a derivative of ethylenediamine and belongs to the class of organic compounds known as diamides. Its molecular structure is characterized by high symmetry, contributing to its stability as a crystalline solid.

Core Chemical Identification

• IUPAC Name: N,N'-Ethane-1,2-diylbis(N-acetylacetamide)

• Molecular Formula: C₁₀H₁₆N₂O₄

• Molecular Weight: 228.24 g/mol

• CAS Number: 10543-57-4

• EINECS Number: 234-123-8

• MDL Number: MFCD00014967

• Merck Index: 14, 9028

• Beilstein Reference (BRN): 1795711

Synonyms and Other Names
TAED is known by several names in scientific literature and industrial patents, including:

• N,N'-Ethylenebis(N-acetylacetamide)

• N,N'-Ethylenebis(diacetamide)

• 3,4-Diacetyl-3,4-diaminohexane-2,5-dione

• N,N,N',N'-Tetraacetylethylenediamine

• N-Acetyl-N-[2-(diacetylamino)ethyl]acetamide

Physical Properties

• Appearance: White to off-white crystalline powder or free-flowing granules.

• Melting Point: 149 - 154 °C. This relatively high melting point indicates good thermal stability, essential for storage and handling.

• Density: Approximately 0.9 g/cm³, making it lighter than water.

• Solubility in Water: Slightly soluble at room temperature (approximately 1 g/L at 20 °C). However, industrial granulated forms are engineered to disperse and dissolve rapidly in the wash liquor.

• Boiling Point: 140 °C at 1.5002 mmHg (decomposes before boiling at atmospheric pressure).

• Vapor Pressure: 0 mmHg at 25 °C, confirming it is non-volatile.

• Refractive Index: Estimated at 1.4550.

• pKa: Predicted to be -1.23 ± 0.70, indicating strong acidic character under certain conditions.

• Storage Conditions: Must be stored in a cool, dry place (2-8 °C is recommended), away from moisture and direct sunlight to maintain stability.

2. Scientific Mechanism of Action: The Perhydrolysis Reaction

The primary function of TAED is as a bleach activator. Its mechanism is a classic example of applied chemistry, overcoming a fundamental limitation of oxygen-based bleaches.

The Problem with Hydrogen Peroxide
Laundry detergents often contain sodium percarbonate or sodium perborate. When dissolved in water, these compounds release hydrogen peroxide (H₂O₂). While H₂O₂ is a good oxidizer, its bleaching action is very slow and ineffective at low temperatures (below 60 °C). To be effective, it typically requires water temperatures above 80 °C, which is energy-intensive and can damage delicate fabrics.

The TAED Solution: Perhydrolysis
TAED solves this problem through a chemical reaction called perhydrolysis.

1. Reaction: TAED reacts rapidly with the hydrogen peroxide anion (HOO⁻) present in the alkaline wash liquor.

2. Product Formation: This reaction produces peracetic acid (CH₃C(O)OOH) . Peracetic acid is a much more powerful oxidizing agent than hydrogen peroxide and remains highly effective at low temperatures (between 20 °C and 60 °C).

The reaction is a two-step process:

• Step 1: TAED + H₂O₂ → Triacetylethylenediamine (TriAED) + Peracetic acid

• Step 2: TriAED + H₂O₂ → Diacetylethylenediamine (DAED) + Peracetic acid

Result: Each molecule of TAED generates two molecules of peracetic acid. The newly formed peracetic acid then rapidly oxidizes the chromophores (color-bearing chemical bonds) in stains like tea, wine, and grass, breaking them down into smaller, colorless, and water-soluble substances that can be easily rinsed away. This entire process is what allows for effective, energy-saving low-temperature washing.

3. Detailed Applications and Industrial Uses

TAED's unique properties make it an indispensable component in various sectors.

Laundry Detergents

This is by far the largest application for TAED, with an estimated annual global consumption of around 75 kilotons.

• Concentration: Typically constitutes 1.4% to 13% of the detergent formulation, depending on the product's target market (economy to premium).

• Stain Removal: Highly effective against organic stains such as tea, coffee, red wine, fruit juices, grass, and body soils.

• Compatibility: Exhibits excellent compatibility with other detergent components like surfactants (anionic, non-ionic), enzymes (proteases, lipases, amylases), and builders, ensuring a synergistic cleaning effect.

• Energy Savings: By enabling effective washing at 30-60 °C, it significantly reduces household energy consumption and carbon footprint.

Automatic Dishwashing Detergents

TAED is a key ingredient in modern machine dishwashing products.

• Tea Stain Removal: Effectively removes stubborn tea and coffee stains from cups and porcelain.

• Cleaning: Helps break down protein and starch-based food residues on plates, glasses, and cutlery.

• Hygiene: The generated peracetic acid provides a powerful disinfection effect, eliminating bacteria and viruses from surfaces.

Industrial & Institutional Cleaning

• Hard Surface Disinfectants: Used in formulations for hospitals, food processing plants, and commercial kitchens due to its broad-spectrum biocidal activity (bactericidal, virucidal, fungicidal, and sporicidal).

• Deodorizing: Its oxidizing action helps neutralize malodorous compounds, providing a deodorant effect.

Textile and Paper Industry

• Textile Bleaching: Used as an activator in hydrogen peroxide bleaching baths for cotton and other cellulosic fibers. It offers a gentler alternative to chlorine-based bleaches, resulting in less fiber damage and superior whiteness.

• Pulp Bleaching: Applied in the paper industry for bleaching wood pulp, particularly in recycling processes to de-ink wastepaper and increase brightness.

Other Niche Applications

• Denture Cleaners: Provides both stain removal and disinfection in one tablet.

• Carpet Cleaners: Enhances the removal of deep-set stains.

• Water Treatment: Potential for use in specialized disinfection applications.

4. Environmental and Toxicological Profile

TAED is frequently cited as a model for green chemistry due to its exceptional environmental and safety profile.

Ecotoxicological Properties

• Biodegradability: TAED and its primary breakdown products (TriAED and DAED) are readily biodegradable. In standard OECD tests, they are rapidly and completely mineralized by microorganisms in wastewater treatment plants into carbon dioxide, water, and biomass, leaving no persistent or harmful metabolites.

• Aquatic Toxicity: It exhibits very low toxicity to aquatic organisms, including fish, daphnia, and algae. It does not bioaccumulate in the food chain.

• Terrestrial Toxicity: Similarly low toxicity is observed for soil-dwelling organisms.

Human Health and Safety

• Acute Toxicity: TAED has very low acute oral and dermal toxicity. It is considered practically non-toxic.

• Irritation: It is non-irritating to the skin and only mildly irritating to the eyes. In its granulated form, it poses minimal risk.

• Sensitization: It is not a skin sensitizer, meaning it has a very low potential to cause allergic reactions.

• Genotoxicity and Carcinogenicity: Extensive testing has shown no evidence of mutagenic, carcinogenic, or reproductive toxicity effects. It is not classified as a carcinogen.

5. Market Forms: Colored TAED

While the pure chemical is white, TAED is often commercially available in colored, granulated forms. This is done to improve handling characteristics, reduce dusting, and sometimes for brand or product line differentiation.

• White TAED: The standard, uncolored form.

• Blue TAED: The most common colored variant. The blue color can help mask any yellowing of the fabric or signal a "brightening" effect to the consumer. It is often formulated with optical brighteners and coated with binders like sodium carboxymethyl cellulose (Na-CMC) for enhanced stability and performance.

• Green TAED: Used in specific detergent formulations, often those marketed as "eco-friendly" or with specific fragrance profiles.

• Red TAED: Less common, but used for specialized industrial applications or as a distinctive marker.

The granulation process (using binders like Na-CMC) improves flowability, prevents dust formation, and ensures the product remains stable during storage and transport.

6. Sourcing, Supply Chain, and Logistics

TAED is a globally traded commodity with a well-established supply chain.

Major Producing Regions: The primary manufacturing hubs are in China and Europe. Major chemical companies and specialized producers dominate the market.

Sourcing Platforms: It is widely available on major B2B platforms such as Alibaba, ChemNet, and EC21.

Procurement Considerations:

• Specifications: Key parameters to specify include purity (typically >99%), particle size distribution, granulation type (spray-dried, extruded), and color.

• Packaging: Commonly supplied in 25 kg multi-layer paper bags, 500 kg big bags, or on pallets.

• Pricing: Prices are volatile and depend on raw material costs (especially acetic anhydride), energy prices, supply/demand dynamics, and global logistics. Pricing is significantly lower for bulk, tonnage orders compared to small laboratory-scale quantities.

• Storage and Shelf Life: To maintain stability and prevent hydrolysis, TAED must be stored in a cool (2-8 °C is optimal for long-term storage, but ambient cool, dry conditions are often acceptable for shorter periods), dry, and well-ventilated area, away from direct sunlight and moisture. Under optimal conditions, the shelf life is typically 12 to 24 months.

7. Technical Formulation Guidelines

When incorporating TAED into a detergent formulation, several factors are crucial for optimal performance:

• Ratio: The molar ratio of the oxygen source (e.g., sodium percarbonate) to TAED should be optimized. A typical weight ratio is for TAED to constitute 20-50% of the total bleach system weight.

• pH: TAED performs best in an alkaline environment, typically at a pH of 9-11, which is the standard pH range for washing detergents.

• Temperature: It is most effective in the 30-60 °C range.

• Stabilizers: The presence of chelating agents (like phosphonates or EDTA) in the formulation is beneficial. They bind trace heavy metal ions (like iron, copper, manganese) which can catalytically decompose hydrogen peroxide and peracetic acid, thereby ensuring the TAED system works efficiently.

Why Should TAED Be Used? (Reasons for Use)

The primary reason for using TAED is its ability to provide effective bleaching at low temperatures. Considering modern washing habits (30-60°C), this feature makes it indispensable. Here are the detailed justifications:

• Low-Temperature Efficacy: Oxygen-based bleaches like sodium perborate or percarbonate are highly inefficient below 60°C. TAED reacts with the hydrogen peroxide released by these substances to form peracetic acid. Peracetic acid is a much stronger bleaching agent with a high oxidation potential, effective even at temperatures as low as 20°C. Its optimal activity spectrum is between 30-60°C.

• Superior Stain Removal: The peracetic acid generated breaks down the chemical structure of stubborn organic stains such as tea, coffee, red wine, fruit juices, ketchup, blood, and grass, facilitating their removal.

• Energy and Cost Savings: By eliminating the need for near-boiling wash temperatures (achieving effective results at 40-60°C), it leads to significant energy conservation and reduces washing costs.

• Hygiene and Disinfection: Peracetic acid possesses strong bactericidal, virucidal, and fungicidal properties. Consequently, products containing TAED ensure a high level of hygiene during the wash cycle and eliminate unpleasant odors (like tobacco or food smells) through oxidation.

• Material Safety and Compatibility: Unlike chlorine-based bleaches, peracetic acid generated from TAED does not damage fabric fibers or colors under recommended usage conditions. Furthermore, it exhibits excellent compatibility with enzymes, optical brighteners, and other detergent components.

• Environmentally Friendly Profile: TAED is toxicologically harmless, readily biodegradable, and completely mineralizes. It has low ecotoxicity for aquatic life and is neither mutagenic nor teratogenic.

Usage Ratios (Concentrations)

The concentration of TAED in formulations varies depending on the product type and the desired effect. The typical usage ratios found in the search results are as follows:

These ratios are optimized for different formulations, ranging from traditional powder detergents to concentrated or compact detergents. In compact powders, for instance, an effective bleaching system is created to save volume and weight.

Are There Alternatives?

Yes, alternatives to TAED do exist. They primarily fall into two categories:

1. Direct Chemical Alternatives (Other Bleach Activators):
Other bleach activators have been developed on the market as alternatives to TAED. The search results mention a product named PERAKT.

• PERAKT: It is produced as an alternative to TAED and can be used in the same application areas and similar ratios. The reported advantage is that it may provide more effective results at even lower temperatures compared to TAED.

2. Different Bleaching Systems:
Different chemical systems used under specific conditions or in certain regions can also serve as alternatives to TAED. However, these systems may have disadvantages in terms of environmental impact or material safety.

• Chlorine-based Bleaches (Sodium Hypochlorite): They are still used, particularly in cold-wash regions like North America and the Far East. They are reactive at low temperatures and are powerful disinfectants. However, they carry a high risk of damaging fibers and dyes and raise environmental concerns, such as the formation of halogenated compounds in wastewater.

Sectoral Usage Table

The applications of TAED across different sectors are summarized in the table below:

Application Areas and Forms

The method of applying TAED varies depending on the product type and the sector in which it is used.

• Application Form in Detergents and Cleaning Products:

  • Formulation: TAED, in its powder or granule form, is incorporated into the detergent formulation by physically mixing it with other dry components (sodium percarbonate, enzymes, surfactants, builders). The granulation process (often using Na-CMC) prevents the product from dusting, improves its flowability, and ensures rapid dissolution in the wash water.

  • Coloring: TAED granules are available on the market in blue, green, red, and white colors. This coloring is usually for product identification or aesthetic purposes and does not affect performance.

  • Mechanism of Action: When the product is added to water, the TAED granules dissolve and react with the hydrogen peroxide released from sodium percarbonate (or a similar source) to form peracetic acid in-situ. This reaction occurs within minutes in the washing solution.

• Application Form in the Textile and Paper Industry:

  • In these sectors, TAED is used as a process chemical. It is added to bleaching baths at specific concentrations and works in conjunction with hydrogen peroxide to whiten fibers or pulp.