Disodium Salt of 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid（HEDP·Na2）

Aliases: Disodium Hydroxyethylidene Diphosphonate, Etidronate Disodium, CubleK2012 Solid
CAS No.: 7414-83-7
Molecular Formula: C₂H₆O₇P₂Na₂
Relative Molecular Mass: 250
Structural Formula:

Performance and Applications

HEDP·Na₂ is an organophosphonic acid scale and corrosion inhibitor. It can form stable complexes with various metal ions such as iron, copper and zinc, and can dissolve oxides on the metal surface. It still maintains excellent corrosion and scale inhibition performance at 250℃, is highly stable at high pH values, is not easy to hydrolyze, and is not easy to decompose under general light and heat conditions. Its acid and alkali resistance, and chlorine oxidation resistance are better than other organophosphonic acids (salts). It can form six-membered ring chelates with metal ions in water, especially calcium ions, thus it has good scale inhibition effect and obvious threshold effect. When used in combination with other water treatment agents, it exhibits an ideal synergistic effect.

HEDP·Na₂ is widely used in scale and corrosion inhibition of industrial circulating cooling water systems in electric power, chemical, metallurgical, fertilizer and other industries, as well as medium and low pressure boilers, oilfield water injection and oil pipeline transportation.

In the light textile industry, HEDP·Na₂ can be used as a cleaning agent for metals and non-metals, a peroxide stabilizer and fixing agent in the bleaching and dyeing industry, and a complexing agent in cyanide-free electroplating industry.

Technical Specifications

Usage Method

The general concentration of HEDP·Na₂ is 2~20mg/L when used as a scale inhibitor, 20~100mg/L when used as a corrosion inhibitor, and 1000~2000mg/L when used as a cleaning agent. It is usually used in combination with polycarboxylic acid type scale inhibitor dispersants.

Packaging and Storage

HEDP·Na₂ liquid is packed in plastic drums, Standard capacities: 25kg, 250kg, 1250kg (IBC tank).Note: Packaging weight can be adjusted according to customer requirements. HEDP·Na₂ solid is packed in plastic woven bags lined with polyethylene bags, with a net weight of 25kg per bag, or customized according to user requirements. Store in a cool indoor place. The shelf life for both solid and liquid is twelve months.

Safety Protection

HEDP·Na₂ is weakly acidic. Pay attention to labor protection during operation. Avoid contact with skin, eyes, etc. In case of contact, rinse immediately with plenty of clean water.