Description
Structural formula:
Performance and Applications:
HEDP is an organic phosphonate scale inhibitor and corrosion retardant that forms stable complexes with various metal ions, including iron, copper, and zinc, and can dissolve oxides on metal surfaces. It maintains excellent corrosion inhibition and scale prevention even at 250℃, remains highly stable under high pH conditions, is resistant to hydrolysis, and generally does not decompose under normal light and thermal conditions. It exhibits superior acid-alkali resistance and chlorine oxidation resistance compared to other organic phosphonates (salts). HEDP can form six-membered chelate rings with metal ions in water, especially calcium ions, thereby delivering outstanding scale inhibition performance and demonstrating a pronounced solubility-limiting effect. When used in combination with other water treatment agents, it exhibits an ideal synergistic effect.
HEDP solid is a high-purity product suitable for regions with severe winter cold; it is particularly well-suited as a cleaning agent in the electronics industry and as an additive in daily chemical products.
HEDP is widely used in industrial circulating cooling water systems—such as those in power, chemical, metallurgical, and fertilizer industries—as well as in medium- and low-pressure boilers, oilfield water injection systems, and oil pipelines, where it serves as an effective scale inhibitor and corrosion inhibitor. In the light textile industry, it can be used as a cleaning agent for both metallic and non-metallic surfaces; as a stabilizer for peroxides and a color-fixing agent in the dyeing and bleaching industries; as a complexing agent in cyanide-free electroplating processes; and in the pharmaceutical industry as a carrier for radioactive elements.
Technical indicators:
| Project | Indicator | ||
| Complies with GB/T 26324-2010 | —— | Complies with HG/T 3537-2010 | |
| Appearance | Colorless or pale yellow transparent liquid | White crystal | |
| Active ingredient (calculated as HEDP)% | ≥50.0 | ≥60.0 | ≥90.0 |
| Active ingredient (as HEDP·H) 2 O count)% | —— | —— | ≥97.0 |
| Phosphorous acid (in the form of PO) 3 3- Count)% | ≤2.0 | ≤2.0 | ≤0.8 |
| Phosphoric acid (as PO) 4 3- Count)% | ≤0.8 | ≤0.8 | ≤0.5 |
| Chloride (as Cl) – Count)ug/g | ≤200 | ≤100 | ≤100 |
| Iron (as Fe²⁺) + Concentration mg/L | ≤20.0 | ≤10.0 | ≤10.0 |
| Density (20℃) g/cm³ | ≥1.36 | ≥1.40 | —— |
| Calcium chelation value mg/g | ≥450 | ≥500 | —— |
| pH value (1% aqueous solution) | 1.5–2.0 | 1.5–2.0 | 1.5–2.0 |
How to use:
HEDP is typically used at concentrations of 1–10 mg/L as an antiscalant; at concentrations of 10–50 mg/L as a corrosion inhibitor; and at concentrations of 1,000–2,000 mg/L as a cleaning agent. It is usually used in combination with polycarboxylate-based scale inhibitors and dispersants. When used in other industries, the dosage should be determined through experimentation.
Packaging and Storage:
HEDP liquid is packaged in plastic drums, with each drum containing either 25 kg or 250 kg, or according to the customer’s specific requirements. The solid form is packaged in plastic woven bags lined with polyethylene bags, with each bag having a net weight of 25 kg, or as specified by the customer. Store in a cool, well-ventilated indoor area, protected from moisture; the shelf life is twelve months.
Security protection:
HEDP is acidic; during handling, pay attention to occupational safety measures and avoid contact with skin, eyes, and other sensitive areas. If contact occurs, immediately rinse thoroughly with plenty of water.