Water-soluble chelating agent EDTA-4Na

EDTA-4Na (Ethylenediaminetetraacetic acid tetrasodium salt)

Introduction

EDTA-4Na is a representative chelating agent (complexing agent) that strongly binds to metal ions. It is particularly highly water-soluble and widely used in various fields, from industrial applications to daily necessities, analysis, and medical fields. On the other hand, due to its strong metal sequestering ability and alkalinity, it is a chemical substance that requires careful attention to its usage conditions.

Basic Information

• Chemical Name: Ethylenediaminetetraacetic acid tetrasodium salt
• Chemical Formula: C₁₀H₁₂N₂Na₄O₈
• Abbreviation: EDTA-4Na, EDTA・4Na
• Classification: Chelating agent (Complexing agent)
• Appearance: White powder

Key Features

① Strong Chelating (Complexing) Action

EDTA-4Na binds very strongly to the following metal ions:

• Ca²⁺ (Calcium)
• Mg²⁺ (Magnesium)
• Fe³⁺ / Fe²⁺ (Iron)
• Cu²⁺, Zn²⁺, Ni²⁺, etc.

➡ Its primary role is to sequester metal ions and suppress their reactivity and adverse effects.

② Very High Water Solubility

➡ Its high solubility is a major practical advantage.

③ Alkalinity

• 1% aqueous solution pH: Approx. 10.5-11.5
• For systems and products affected by pH, adjustment of compounding amount and conditions is necessary.

Main Applications

1. Water Treatment and Cleaning Fields

• Boiler water treatment
• Softening of industrial water
• Metal sequestration in cleaning agents (scale prevention)
  ➡ The purpose is to capture hardness components (Ca²⁺, Mg²⁺)

2. Chemical Industry and Analysis Fields

• Masking agent for metal ions
• Titration analysis (EDTA titration)
• Removal of trace metals that act as catalyst poisons

3. Cosmetics and Daily Necessities

• Quality stabilization of shampoos, detergents, lotions, etc.
• Prevention of discoloration and degradation caused by metals
  * Widely used both domestically and internationally

4. Medical and Bio Fields (*Limited applications)

• Additive for blood tests (anticoagulant)
• Inhibition of metalloenzyme activity
  * For pharmaceutical applications, strict standards and purity control are essential

Handling and Precautions

⚠ Effects of Alkalinity

• Irritation to skin and eyes
• Gloves and protective equipment recommended during handling

⚠ Strength of Metal Sequestration

• May sequester even necessary trace metals
• Can be an inhibitory factor in biological and reaction systems
• Consideration needed for changes in metal behavior in wastewater

Storage Conditions

• Hygroscopic → Store in a sealed container
• Avoid high temperatures and direct sunlight

Summary

• EDTA-4Na is a very powerful chelating agent
• Highly water-soluble and strongly alkaline
• Applications are diverse, including water treatment, analysis, daily necessities, and medical fields
• It is important to use it with an understanding of its pH effects and strong metal sequestering ability

Last updated: April 27, 2026