| HS Code | 892630 |
| Productname | EDTA CuNa2 |
| Chemicalname | Copper disodium ethylenediaminetetraacetate |
| Synonyms | Copper disodium EDTA; Disodium copper EDTA; CuEDTA disodium; EDTA copper sodium salt |
| Casnumber | 14025-15-1 |
| Einecenumber | 237-864-5 |
| Molecularformula | C10H12CuN2Na2O8 |
| Molecularweight | 397.73 g/mol |
| Appearance | Blue crystalline powder |
| Odor | Odorless |
| Coppercontent | 15.0–16.0% |
| Assay | ≥99.0% |
| Ph | 6.0–8.0 (1% aqueous solution) |
| Solubility | Soluble in water |
| Moisture | ≤0.5% |
| Waterinsolublematter | ≤0.1% |
| Heavymetals | ≤10 ppm |
| Arsenic | ≤3 ppm |
| Stability | Stable under normal temperature and pressure |
| Storage | Store in a cool, dry, ventilated area away from moisture |
As an accredited EDTA CuNa2 factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | EDTA CuNa2 is packaged in 25 kg polyethylene-lined fiberboard drums with sealed inner liners and clear chemical labels. |
| Container Loading (20′ FCL) | EDTA CuNa2 in 25 kg bags, palletized, securely stowed in a 20′ FCL container with proper labeling and MSDS. |
| Shipping | Typically, EDTA CuNa2 is shipped as UN 3077, Environmentally Hazardous Substance, Solid, n.o.s. (Copper disodium EDTA), Class 9, Packing Group III, Marine Pollutant. Use UN-approved packaging, Class 9/marine pollutant labels, and comply with DOT/IMDG/IATA rules; verify current SDS and local regulations. |
| Storage | Store EDTA CuNa2 in a cool, dry, well-ventilated area in a tightly closed container. Keep away from moisture, acids, strong oxidizers, and incompatible chemicals. Protect from direct sunlight and heat. Avoid dust generation, and store separately from food, feed, and drinking water. Use appropriate secondary containment to prevent spills. Ensure containers are labeled and inspect regularly for leaks or damage. |
| Shelf Life | EDTA CuNa2: Stable under normal storage; typical shelf life two years if kept sealed, dry, cool, and protected from light. |
At soil pH above 7.2, soluble cupric sulfate added to calcareous mineral soil is rapidly converted to sparingly soluble carbonate and hydroxide phases in the calcite reaction shell surrounding the granule. The CuNa₂EDTA complex, with a stability constant of log K 18.8 at 0.1 M ionic strength, remains intact above pH 8.5 and maintains a diffusion gradient toward the root apoplast. In the EU, this compound is placed within the chelated micronutrient group under Regulation (EU) 2019/1009, where EDTA is a permitted chelating agent and the declared water-soluble copper fraction is subject to tolerance limits; in the United States, state fertilizer registrations under AAPFCO require separate guarantees for total water-soluble copper and chelated copper. Typical granular soil-correction formulations contain 7–15% total Cu w/w, of which at least 80% is chelated. Field application rates on deficient mineral soils range from 0.5 to 2.0 kg Cu/ha per season, with the lower end reserved for soils testing below 0.2 mg/kg DTPA-extractable Cu. Production is carried out by blending CuNa₂EDTA into a dry NPK base prior to pan granulation at 70–85°C; spray water is limited to 4–6% w/w to prevent premature caking. Co-granulation with ammonium phosphate is limited because localized free Cu²⁺ release can form insoluble copper phosphate; a 1–2% oil-based pre-coating on the chelate granules mitigates this interaction. After drying to 2–3% moisture and screening at 2–4 mm, the product is coated with anti-caking oil. Terminal product types include water-soluble granules for broadcast or in-furrow application, microgranular starter fertilizers, and liquid suspension concentrates containing 30–50 g/L Cu for drip-tape injection. Repeated high-rate applications must be checked against the sodium adsorption ratio of irrigation water because the disodium salt contributes 11–12% sodium by weight.
Foliar application of CuNa₂EDTA is specified when soil pH and bicarbonate concentration depress root copper uptake despite adequate total soil copper reserves. The chelate’s water solubility and small molecular size permit cuticle penetration with less leaf injury than cupric sulfate sprays on tender foliage. Under Regulation (EU) 2019/1009, the product is registered as a straight fluid or solid micronutrient fertiliser; US state AAPFCO labels require a guarantee for chelated Cu. Tank mix concentrations are prepared at 0.05–0.30 g/L Cu, equivalent to 0.4–1.2 L/ha of a 5% Cu formulation in 200–400 L of water. Application is timed to pre-bloom in apple and pear, the 5–7 leaf stage in maize, and 15–20 cm canopy height in potato. Liquid concentrate production involves dissolving CuNa₂EDTA in deionized water at 35–45°C with continuous agitation, adjusting to pH 5.5–6.5 with citric acid, adding a non-ionic wetting agent at 0.1–0.3% v/v, and passing through 25 µm filtration before filling. Terminal product types include water-soluble sachets for field mixing, liquid foliar concentrates, and suspension formulations for aerial application in cereals. Application is withheld when leaf surface temperature exceeds 28°C or when alkaline silicon-based surfactants are present, because rapid evaporation increases residue concentration and stomatal closure reduces cuticular uptake; published data for CuNa₂EDTA on open blossom stages is limited.
Because dietary phytate and zinc oxide compete for copper uptake in the jejunum, feed-grade CuNa₂EDTA is incorporated into trace mineral premixes for monogastric species. The feed-additive status is governed by Regulation (EC) No 1831/2003; in the EU, copper compounds are subject to total copper maximum levels established under Regulation (EU) 2018/1039, including 150 mg/kg complete feed for piglets up to four weeks after weaning and 25 mg/kg for fattening pigs. In broiler grower diets, CuNa₂EDTA is included to provide 10–25 mg Cu/kg complete feed; published data for CuNa₂EDTA in finishing pig diets under the existing EU maximum copper ceilings is limited, so dosing is established by product registration conditions rather than extrapolation from sulfate dose-response trials. Where liver copper retention is used as the efficacy endpoint, analytical method selection follows nitric acid digestion with ICP-MS, and published peer-reviewed data for this exact chelate configuration is limited. The production route consists of pre-blending the anhydrous powder at 0.5–2.0% w/w into a calcium carbonate carrier, followed by ribbon blending at 20–25 rpm for 8–12 min; moisture is maintained below 5% w/w because the powder is hygroscopic above 60% relative humidity. The compound is not combined with choline chloride in the same premix due to exothermic moisture uptake and oxidative degradation. Terminal product types include mineral premixes for integrated feed mills, top-dress supplements, and extruded aquafeed pellets in which CuNa₂EDTA is dispersed through a vacuum coater at 3–5% oil inclusion.
Closed-loop hydroponic nutrient delivery systems impose a precipitation constraint that requires copper and phosphate separation unless the cupric ion is fully chelated by disodium EDTA. CuNa₂EDTA stock solutions are formulated to deliver 0.02–0.10 mg/L Cu in the final nutrient solution, with pH 5.6–6.2 maintained because lower pH progressively protonates EDTA and releases free Cu²⁺, while higher pH increases carbonate and phosphate scaling in hard water. In the EU, the product is regulated as a fluid fertilising product under Regulation (EU) 2019/1009; in the United States, state fertilizer registrations require a guaranteed water-soluble copper percentage and a chelated copper percentage. Stock concentrates are prepared at 1:100 to 1:200 dilution, filtered through 50 µm mesh, and injected through venturi or proportional dosing pumps. Recirculating systems require daily monitoring of Cu concentration by ICP-OES or colorimetric DTPA kits; drainage water copper is maintained below 0.2 mg/L in operational guidelines. Terminal products include two-part A/B liquid concentrates, pre-weighed water-soluble sachets, and slow-release tablets for hydroponic float beds and aeroponic nutrient tanks.
In printed circuit board through-hole metallization, a conductive copper deposit is required on non-conductive epoxy-glass substrates before electrolytic panel plating. CuNa₂EDTA supplies both the cupric ion reservoir and chelating capacity that stabilises the bath against cupric oxide precipitation at high operating pH. The bath is made up to a cupric ion concentration of 1.8–3.0 g/L Cu, with additional tetrasodium EDTA to maintain a total EDTA-to-Cu molar ratio of 2.0–2.5, sodium hydroxide to pH 12.4–12.8, and formaldehyde 37% solution at 5.0–10.0 mL/L. Air agitation is maintained at 0.5–1.0 L/min/L to avoid stagnation in through-holes with aspect ratios above 6:1. The critical control window is narrow: below pH 12.2, deposition rate falls below 1.0 µm/h, while above 12.9 the parasitic Cannizzaro reaction consumes formaldehyde and generates carbonate, reducing bath life. Temperature is held at 45–55°C with a tolerance of ±1.5°C; the deposition rate approximately doubles per 10°C increase, but operation above 55°C produces void-prone deposits because hydrogen evolution at the substrate surface interferes with copper adhesion. Analytical control uses iodometric titration for cupric ion and complexometric titration for free EDTA; carbonate is removed by cooling precipitation at 8–10°C when carbonate exceeds 60 g/L. Process qualification references IPC-6012 for rigid printed boards, with adhesion testing per IPC-TM-650 2.4.8 and microsection inspection after thermal stress for backlight voids below 5%. The terminal product is a 0.3–1.0 µm electroless copper deposit in through-holes and microvias, subsequently reinforced by electrolytic copper to 20–25 µm before pattern etching.
| Parameter | Lower action limit | Upper action limit | Primary failure mode |
|---|---|---|---|
| Cupric ion | 1.8 g/L | 3.0 g/L | Low deposition rate / rough deposit |
| EDTA/Cu molar ratio | 2.0 | 2.5 | Precipitation / unstable reducing agent |
| pH | 12.2 | 12.9 | Low rate / Cannizzaro carbonate formation |
| Temperature | 45°C | 55°C | Slow initiation / hydrogen voids |
| Formaldehyde 37% | 5.0 mL/L | 10.0 mL/L | Incomplete reduction / bath outgassing |
Competitive EDTA CuNa2 prices that fit your budget—flexible terms and customized quotes for every order.
For samples, pricing, or more information, please contact us at +8615380400285 or mail to sales2@ascent-chem.com.
We will respond to you as soon as possible.
Tel: +8615380400285
Email: sales2@ascent-chem.com
Flexible payment, competitive price, premium service - Inquire now!
Ethylenediaminetetraacetic acid copper disodium salt (CAS 14025-15-1; EC 237-864-7), commonly designated EDTA CuNa₂, is a chelated copper complex with the molecular formula C₁₀H₁₂CuN₂Na₂O₈ and a calculated molecular mass of 397.74 g mol⁻¹ on an anhydrous basis. The complex consists of a Cu²⁺ ion coordinated by four carboxylate oxygen atoms and two amine nitrogen atoms of the EDTA ligand, with two sodium ions providing countercharge. The theoretical copper content is 15.98% w/w on an anhydrous basis; commercial agricultural and technical powders typically assay within 15.0%–15.5% total copper when free moisture and variable hydration are included. The material is supplied as a blue crystalline powder or fine crystals, freely soluble in water to produce a clear blue solution, and is used where copper must remain soluble and available under neutral-to-alkaline conditions that would otherwise precipitate uncomplexed copper salts.
On a dry-weight basis, the product contains one molar equivalent of EDTA and one molar equivalent of Cu²⁺. The disodium salt form is deliberately selected over the free acid because the carboxylate counterions adjust aqueous pH upward and improve cold-water dissolution. In a 1% w/v aqueous solution at 25 °C, a typical technical grade yields pH 6.0–8.0, with electrical conductivity dominated by the two sodium counterions. Water-insoluble matter remains below 0.1% because unreacted copper oxide or basic copper carbonate is removed by filtration before crystallization or spray drying. Loss on drying at 105 °C is usually specified at ≤5.0%, and heavy-metal contamination is typically controlled to ≤0.001% for As, Pb, and Cd in fertilizer-grade material. No single ISO or ASTM specification sheet governs EDTA CuNa₂; the numerical ranges above are common supplier acceptance criteria and must be verified against the certificate of analysis for each batch.
Product grades are normally identified by supplier-specific codes rather than a universal model number. Common commercial designations include technical grade, fertilizer grade, and pure grade. Fertilizer-grade material is standardized on chelated copper content, whereas electroplating-grade material may have lower chloride and sulfate impurities. The particle size distribution of a spray-dried powder is typically 100–200 µm for the main fraction, with bulk density 0.60–0.80 g cm⁻³, but these physical values are supplier-dependent and should be confirmed on the certificate of analysis.
Production-scale chelation is conducted in glass-lined or 316L stainless steel reactors by dispersing copper oxide or basic copper carbonate in water with disodium EDTA at a controlled molar ratio of 1.00:1.00 to 1.02:1.00 ligand-to-copper. The reaction is maintained at 70–90 °C under atmospheric pressure until the slurry clarifies and free copper ion concentration, measured by ion-selective electrode, falls below 5 mg L⁻¹. The solution pH is then adjusted with either sodium hydroxide or the free acid form of EDTA to the target range, cooled, clarified through a 0.5–1.0 µm filter, and concentrated in a falling-film evaporator before spray drying. On full-scale spray dryers with inlet air temperatures of 160–190 °C and outlet temperatures of 80–95 °C, the main processing bottleneck is control of residual moisture and particle agglomeration. At ambient relative humidity above 60%, the powder may absorb water and undergo caking, so transfer and packaging are conducted under dehumidified air.
Copper sulfate pentahydrate supplies approximately 25.45% copper by mass, but its copper ion is immediately subject to hydrolysis and precipitation as copper hydroxide, carbonate, or phosphate in high-pH and calcareous systems. At pH 7.5–8.5 typical of calcareous soil solution, free Cu²⁺ activity is governed by precipitation rather than by total soluble copper; this is why soil-applied copper sulfate often has low recovery in leaf tissue and why repeated applications are necessary. EDTA CuNa₂ alters this behavior because the Cu²⁺ is bound by the EDTA⁴⁻ ligand. The conditional stability constant for the Cu-EDTA complex is sufficiently high to maintain the majority of copper in soluble chelated form at pH 6.0–8.0. In hydroponic stock solutions containing phosphate and carbonate, a 1:100 dilution of a 0.5% Cu-EDTA solution remains clear, whereas an equivalent Cu²⁺ concentration from copper sulfate produces visible precipitate within 24 h under the same bicarbonate alkalinity.
Dilute liquid applications in fertigation are prepared by injecting a stock solution of EDTA CuNa₂ into irrigation water at rates delivering 0.05–0.20 mg L⁻¹ Cu in the root zone for continuous feed programs, or 0.5–2.0 kg ha⁻¹ Cu per season in field vegetable production. The chelated form is compatible with monoammonium phosphate and potassium carbonate at stock-tank concentrations below 10% w/v, though concentrated mixtures should be jar-tested before blending because local water hardness, pH, and sulfate content alter long-term tank stability. In foliar application, spray solutions of 0.02%–0.05% w/v EDTA CuNa₂ are used to correct copper deficiency in cereals and vegetables, with leaf cuticle penetration governing uptake efficiency. The product is also used in controlled-environment agriculture as a component of stock nutrient solutions; in this context, the absence of free Cu²⁺ reduces precipitation on irrigation line emitters and in concentrated stock tanks.
Humic and fulvic acid interactions, high bicarbonate irrigation water, and phosphate fertilizers are the principal antagonists to copper availability in soil and soilless media. The Cu-EDTA chelate is not immune to all dissociation. Below pH 3.0, protonation of the ligand competes with Cu²⁺ and reduces complex stability, while above pH 9.0, hydroxide competition can become measurable in long-duration standing solutions. Under normal fertigation conditions of pH 5.5–7.5, the complex remains intact through the residence time of a recirculating hydroponic system, typically 7–14 days between stock-tank turnovers. Comparative tests using ion-specific electrodes show that free Cu²⁺ in a 0.1 mM EDTA CuNa₂ solution at pH 7.5 is several orders of magnitude lower than in the same total copper concentration supplied as copper sulfate, which explains why leaf chlorosis correction can occur at lower total application rates with the chelate.
Cu-DTPA has a higher published thermodynamic stability constant for Cu²⁺ than Cu-EDTA and may provide better residual solubility in very calcareous media, but it is typically more expensive per unit of delivered copper and persists longer in aqueous systems. Cu-EDDS is biodegradable and is preferred in programs where aqueous persistence of aminocarboxylates is restricted, but published comparative agronomic data for high-pH calcareous soils is limited. Disodium EDTA without copper is not a nutrient source; it is a chelating agent that should not be substituted for EDTA CuNa₂ in copper deficiency correction unless it is first reacted with a copper salt under controlled conditions. Copper sulfate, copper chloride, and copper carbonate are lower-cost sources of copper, but their use in concentrated phosphate-containing fertilizer solution or high-pH irrigation water results in precipitation, uneven nutrient delivery, and emitter clogging.
| Parameter | Typical range or value | Determination method |
|---|---|---|
| Appearance | Blue crystalline powder | Visual inspection |
| Total copper, as-is | 15.0%–15.5% | Acid digestion followed by ICP-OES |
| Water-soluble copper | ≥15.0% | Filtration at 0.45 µm, then ICP-OES |
| pH, 1% aqueous at 25 °C | 6.0–8.0 | Calibrated pH electrode |
| Water-insoluble matter | ≤0.1% | Gravimetric after filtration |
| Loss on drying, 105 °C | ≤5.0% | Drying oven |
| Heavy metals, as Pb/Cd/As | ≤0.001% | ICP-MS after mineralization |
| Copper source | Theoretical Cu content | Behavior in phosphate/carbonate at pH 7.5 | Principal constraint |
|---|---|---|---|
| Copper sulfate pentahydrate | 25.45% | Readily precipitates; free Cu²⁺ activity collapses | Low crop recovery, emitter fouling |
| EDTA CuNa₂ | 15.98% anhydrous | Remains soluble as chelated Cu-EDTA complex | Persistent aminocarboxylate ligand |
| Cu-DTPA | Supplier variable, typically lower than Cu-EDTA | Higher conditional stability in very calcareous media | Higher cost, greater environmental persistence |
| Cu-EDDS | Supplier variable | Similar chelate behavior; biodegradable ligand | Limited published agronomic data |
Operational boundaries include avoiding acidic stock solutions below pH 3.0, avoiding strong reducing agents that can reduce Cu²⁺ to Cu⁺ and destabilize the complex, and avoiding extended exposure of dilute solutions to ultraviolet light in clear containers. Because the ligand is an aminocarboxylate, wastewater containing spent chelated copper should not be treated with conventional hydroxide precipitation alone; oxidative or membrane treatment is required to degrade the ligand before copper removal. Published data on long-term soil accumulation of EDTA-type chelates remains limited, and use rates should therefore conform to regional fertilizer regulations and environmental exposure models.
