N-Ethylaniline brings together the basic structure of aniline with an ethyl group attached to the nitrogen. This modification turns a common chemical feedstock into a more specific building block. While aniline itself has been used since the nineteenth century in dye and pharmaceutical production, adding the ethyl group creates new reaction possibilities and product performance. As with most alkyl-anilines, a seemingly small structural change has a major impact on reactivity, boiling point, and solubility.
The structural formula for N-Ethylaniline is C8H11N. In the molecular diagram, the ethyl chain stands in for one of hydrogen atoms on the nitrogen. This arrangement makes the compound a secondary amine, not a primary one. The molecular weight comes out to 121.18 g/mol. At room temperature, many grades arrive as a colorless to pale yellow oily liquid. You might see it described as “liquid,” though it can develop slight turbidity at lower temperatures.
On the specifics, N-Ethylaniline carries a density around 0.96 g/cm3, with a boiling point near 216°C and a melting point between -15°C and -20°C. The refractive index is measured close to 1.567 at 20°C, and water solubility ends up quite low, about 1 g/L. N-Ethylaniline often features in the form of neat liquid shipped in steel drums or intermediate bulk containers (IBCs). In rare cases, it may be encountered as flakes or powder, but this isn’t the standard experience in industrial labs or production lines.
Factories rely on N-Ethylaniline as a raw material for Ghost Blue, Acid Blue, and solvent dyes. Organic synthesis workflows make use of the compound when pursuing intermediates in pharmaceuticals and agrochemicals. In some rubber production processes, N-Ethylaniline works as an antioxidant or processing aid. It can help adjust the color profiles in ink production or serve as a corrosion inhibitor for metal surfaces. Where you have color chemistry, there’s a decent chance this compound sits somewhere on the path to the end product. The chemical’s secondary amine structure stands up to heat, making it suitable for reactions under high temperature as well as moderate-pressure catalytic conversions.
When laboratories or plants specify a product, the commercial grade usually hits purity above 98% as confirmed by GC analysis. Residue solvents, unreacted starting materials, and heavy metals stay below recognized thresholds for technical-grade aromatic amines. Many suppliers list the HS Code as 2921.42.00, which covers aromatic monoamines in global trade registries.
N-Ethylaniline’s molecular characteristics influence both storage and use. With its low flash point, around 87°C, the chemical presents a flammability risk in environments where ignition sources abound. Chemical stability remains solid at ambient temperatures, but exposure to strong oxidizers—such as nitric acid or potassium permanganate—can spark unwanted side reactions. The chemical withstands short exposure to sunlight, but long-term UV can degrade its aromatic structure, especially in diluted solutions. While the solid phase isn’t common outside research, pure crystals can be grown for analytical purposes—these appear as off-white to faintly yellow irregular solids.
This compound sits among many chemicals that require measured handling. It isn’t classed as an acute toxin at the same intensity as nitrobenzene or some related amines, but it does carry notable hazards. Direct skin contact leads to irritation, and the vapor can irritate the respiratory system. Workers should depend on protective nitrile gloves and goggles. Proper ventilation always helps reduce vapor buildup. Waste streams must be treated, often using incineration or advanced oxidative systems, to prevent groundwater or surface water contamination.
In practice, liquid N-Ethylaniline often arrives in 200-liter steel drums, sometimes plastic-lined to prevent contamination. Handling takes effort, as the liquid can seep through organic rubber seals, making proper containment essential for large-scale shipments. Some facilities dilute N-Ethylaniline in organic solvents to prepare stock solutions for process integration, as this can reduce vapor emissions and increase handling safety. Once opened, containers need to be sealed tightly, with any residual headspace flushed with an inert gas if longer-term storage is required.
Density plays a real part in batching and transfer processes, where accurate mass measurement forms the basis for downstream formulation. At the industrial scale, knowing the density at different temperatures helps ensure that metered deliveries of the chemical match batch requirements. In solution, secondary amines like N-Ethylaniline dissolve well in organic solvents—such as toluene or acetone—but resist mixing with water. This property suits many synthetic steps, as it simplifies extractions and intermediate isolations following reaction completion.
N-Ethylaniline makes the list under the Globally Harmonized System as a harmful and hazardous substance. Acute oral and dermal toxicity fall below the danger threshold for many solvents, though chronic exposure or ingestion can affect the central nervous system. During my own years in chemical plants, I learned the importance of keeping this material off the skin and following Material Safety Data Sheet (MSDS) recommendations at all times. Good local exhaust ventilation, emergency eyewash stations, and double-checking the integrity of all transfer hoses reduce the risk of incident. Employees should report spills or splashes right away, as trace amounts can linger on lab benches or equipment handles, posing a cumulative risk.
Environmentally, N-Ethylaniline can break down under sunlight, but its aromatic structure slows rapid degradation in soil or water. Any production facility generating wastewater with this material faces strict discharge limits, especially if local rules classify aromatic amines as persistent organic pollutants. For chemical waste, high-temperature incineration remains the safest practice, with modern control systems capturing off-gases and residues. At the core, responsible handling and disposal follow both regulatory law and common-sense health protection, with clear procedures adjusted for the specific risks of aromatic secondary amines.
From dye synthesis to pharmaceuticals, N-Ethylaniline persists as a tool for delivering performance and color. My own experience reminds me not to overlook the hazardous profile of what can first appear as just another clear liquid. As demand for advanced materials and specialty chemicals rises, factories and labs receive guidance from trade codes, purity standards, and environmental compliance benchmarks. Each worker, plant manager, and quality inspector plays a role in making sure this chemical brings benefit without bringing avoidable risk along with it.
