Hydrazine hydrate 55% (N2H4.H2O, CAS 10217-52-4 / 7803-57-8) is supplied as a clear aqueous solution at 55% hydrate content, equivalent to roughly 35% hydrazine. It is a versatile reducing agent and nitrogen source used in blowing-agent manufacture, boiler water treatment, agrochemical and pharmaceutical synthesis. The grade below is a low-chloride, low-iron specification – both impurities matter because iron catalyses the decomposition of hydrazine and chloride drives corrosion in the equipment it protects.
Regulatory notice – read before ordering. Hydrazine and its hydrate are toxic, corrosive and classified as carcinogenic in several jurisdictions, and hydrazine-bearing products are controlled as an explosive precursor in some markets above defined concentration thresholds. The 55% hydrate grade described here is a lower-concentration product, and low-concentration hydrazine solutions can generally be exported with the correct documentation – but the classification, licence requirement and permitted end use are set by the destination country and by the concentration of hydrazine (not hydrate) in the product. Confirm the position for your destination before ordering, and tell us the end use so the documentation can be prepared correctly. We supply documentation; the import licence and registration are the buyer’s responsibility.
Specification
| Parameter | Limit | Why it matters |
|---|---|---|
| N2H4.H2O content | 55% min | The active figure. Note that this is hydrate content – the hydrazine (N2H4) content is approximately 35%, and regulatory thresholds are often written on the hydrazine figure |
| Non-volatile content | 0.01% max | Residue after evaporation; indicates inorganic contamination and affects use in boiler and electronic applications |
| Iron (Fe) | 0.0005% max | The critical impurity. Iron catalyses hydrazine decomposition, so a high-iron lot loses assay in storage and can generate gas in a sealed drum |
| Heavy metals (as Pb) | 0.0005% max | Purity gate for pharmaceutical and electronic uses |
| Chloride (as Cl) | 0.003% max | Chloride accelerates corrosion of the stainless steel that hydrazine systems are built from, and poisons some catalysts |
| Sulphate (as SO4) | 0.0005% max | Purity indicator; relevant where the hydrate is used as a reagent rather than a bulk chemical |
Concentration and what the numbers mean
| Expression | Value for this grade | Where it is used |
|---|---|---|
| Hydrate content (N2H4.H2O) | 55% min | The commercial specification basis, and the figure on most certificates |
| Hydrazine content (N2H4) | Approximately 35% | The basis used in most regulatory thresholds, transport classification and hazard communication |
| Water | The balance | Hydrazine hydrate is inherently an aqueous material – the hydrate itself contains about 36% water by mass |
The two figures are the most common source of misunderstanding in this product. A “55% hydrazine hydrate” solution is not 55% hydrazine; it is about 35%. When a regulation, a transport class or a customer specification states a concentration, always confirm which basis it uses before assuming a grade is or is not in scope.
Applications
| Application | Role of hydrazine hydrate | Grade consideration |
|---|---|---|
| Blowing agent manufacture | Raw material in the synthesis of azodicarbonamide (ADC) blowing agents | Bulk grade; iron and chloride limits still matter for reaction control |
| Boiler water treatment | Oxygen scavenger and passivating agent for high-pressure boilers | Low chloride and low iron are essential – the product is protecting steel |
| Agrochemical synthesis | Nitrogen source in triazole, pyrazole and other heterocycle routes | Consistent assay and low metal content |
| Pharmaceutical intermediates | Reducing agent and nitrogen source in API synthesis | Heavy metals and residual impurities must be controlled and documented |
| Polymerisation and reduction | Reducing agent in controlled radical systems and metal reduction | Low iron in particular – iron interferes with the chemistry |
| Water treatment and effluent | Reduction of chromate, dechlorination, metal reduction | Technical grade acceptable |
Handling and storage
| Point | Requirement |
|---|---|
| Toxicity | Hydrazine is toxic by inhalation, ingestion and skin contact, and is a suspected carcinogen. Closed handling, local exhaust ventilation and full PPE are baseline |
| Materials | Stainless steel or polyethylene; avoid copper, brass and other alloys that catalyse decomposition |
| Contamination | Keep away from oxidisers, acids, metal salts and rust. Iron contamination causes gas evolution and assay loss |
| Storage | Sealed, cool, shaded, vented where required. Drums should not be stored long-term in direct sun |
| Fire | Hydrazine solutions are combustible; the hydrate itself is not classified as flammable at this concentration, but the vapour is hazardous and the liquid supports combustion once heated |
| First aid | Flush skin and eyes immediately; hydrazine is absorbed through the skin |
Packaging and documentation
Supplied in polyethylene drums and IBC, with packaging compatible with the material. Every batch ships with a certificate of analysis covering hydrate content, non-volatile matter, iron, heavy metals, chloride and sulphate, plus an SDS in the required language. For export, we can provide the documentation set the destination requires – the export licence and import registration themselves sit with the buyer.
For the technical background, the concentration-versus-compliance question and the applications in depth, see the hydrazine hydrate concentration and export compliance guide and the applications and handling page.
