Industry grade 99% Bis(2-ethylhexyl)amine CAS 106-20-7

 What is Bis(2-ethylhexyl)amine? How does it work?

Bis(2-ethylhexyl)amine, also known as di(2-ethylhexyl)amine or diisooctylamine, is chemically named 2-ethyl-N-(2-ethylhexyl)hex-1-amine. It is a long-chain secondary amine composed of two 2-ethylhexyl (commonly known as isooctyl) hydrophobic alkyl groups linked by a secondary amine nitrogen atom, representing a typical "gemini hydrophobic chain" structure among amine compounds. It is a colorless to pale yellow transparent liquid with a slight ammonia-like odor. It is a "general-purpose" industrial-grade secondary amine raw material used in wet metallurgical extraction, metal corrosion and rust inhibition, petroleum additives, and fine chemical intermediates. Bis(2-ethylhexyl)amine is applied across multiple fields, including metallurgy and mineral processing, machining, metal protection, water treatment, petroleum additives, surfactants, disinfection and hygiene, and the rubber and dye industries.

Basic identification information: Molecular formula C16H35N, molecular weight 241.46, CAS number 106-20-7, EC number 203-372-4, MDL number MFCD00009489, UNII 9U5Q5UV6DB, RTECS number IH6825000, PubChem CID 7791; IUPAC name 2-ethyl-N-(2-ethylhexyl)hexan-1-amine.

Physically, Bis(2-ethylhexyl)amine is a colorless to nearly colorless transparent liquid with a slight ammonia-like odor; melting point approximately -60℃; boiling point at normal pressure approximately 281℃, and boiling point under reduced pressure 123℃/5.2 mmHg; flash point 121-132℃ (data varies slightly from different sources); density approximately 0.78-0.81 g/cm³ (20℃), lighter than water; refractive index approximately 1.44; extremely low vapor pressure (approximately 0.01 mmHg @ 20℃); slightly soluble in water, readily soluble in ethanol, ether, acetone, benzene, chloroform, and various hydrocarbon solvents; it is a flammable liquid.

Chemically, Bis(2-ethylhexyl)amine is a typical secondary amine: the nitrogen atom has an active NH bond and a lone pair of electrons, exhibiting basicity. It can form salts with inorganic and organic acids (hydrochloride, acetate, etc.) and react with carbon dioxide to form carbamates. The NH bond can undergo alkylation (first forming tertiary amines with haloalkanes, then further quaternization to form quaternary ammonium salts), acylation (forming amides with acid anhydrides and acyl chlorides, such as reacting with alkenyl succinic anhydride to form succinimide dispersants), condensation with aldehydes and ketones (Schiff base, Mannich reaction), and ring-opening addition with epoxides. At the same time, it is a weak reducing agent and can be slowly oxidized by long-term exposure to air. It is incompatible with strong oxidizing agents, isocyanates, haloalkanes, peroxides, acids, epoxy resins, etc., and must be stored in a sealed environment under an inert gas atmosphere.

Grading System: Bis(2-ethylhexyl)amine is commercially available in different grades, including industrial grade, reagent grade, and cosmetic raw material grade. This article only introduces the industrial grade. Industrial grade is the most common commercial grade of this product, with a main content ≥98-99%. It is mainly used for large-scale industrial applications such as hydrometallurgical extraction, corrosion and rust inhibition, petroleum additives, and organic synthesis intermediates. It is managed as a hazardous chemical and is intended for use by manufacturing enterprises; it is not directly sold to consumers.

From the perspective of its mechanism of action, Bis(2-ethylhexyl)amine plays an irreplaceable role due to its three-in-one structure of "basic nitrogen head group + two 2-ethylhexyl hydrophobic long chains + active NH bond". The mechanisms of action in different industrial applications are as follows:

Basicity/protonation mechanism (neutralization and complexation)

The lone pair of electrons of nitrogen atoms can be protonated in water to form R2NH2+ ammonium cations, which can neutralize acidic media (acidic oxidation products in metal processing fluids, lubricating oils, and fuels), form ion associations with metal complex anions (hydrometallurgical extraction), and electrostatically adsorb negatively charged surfaces (mineral flotation collection, fiber antistatic finishing).

Bihydrophobic long-chain mechanism (film formation and interfacial activity)

Two branched alkyl groups provide strong hydrophobicity and oil solubility, making them readily soluble in oil and organic phases: they can be oriented to adsorb onto metal surfaces to form a hydrophobic protective film (rust prevention and corrosion inhibition), orient themselves at oil-water interfaces to reduce interfacial tension (emulsification and dispersion), and dissolve in organic media (dye solubilizers, oil-soluble auxiliaries).

NH reactivity mechanism (derivation)

The NH bond of secondary amines can be alkylated, acylated, quaternized, and added to carbon disulfide, making them a common source of nitrogen and hydrophobic groups for the synthesis of quaternary ammonium salt fungicides/phase transfer catalysts, succinimide ashless dispersants, amide pesticide intermediates, and dithiocarbamate rubber accelerators.

In summary, Bis(2-ethylhexyl)amine is a multifunctional industrial-grade long-chain secondary amine chemical. Due to its basic protonation, double hydrophobic long chain, and reactivity with NH4+, it is applicable to multiple fields such as metallurgy, mineral processing, machining, metal protection, water treatment, petroleum additives, surfactants, disinfection and hygiene, pesticides, rubber and dye industries.

What are all the uses of industrial-grade Bis(2-ethylhexyl)amine?

The industrial applications of Bis(2-ethylhexyl)amine cover non-ferrous metal metallurgy, mineral processing, machining, metal protection, water treatment, petroleum additives, surfactants, disinfection and hygiene, pesticides, rubber, dyes, and other fields. The following details each application, from downstream end products to application areas, explaining the application area, corresponding products, and why it is effective for that purpose:

1. Extractant for rare metal hydrometallurgical processes (core application in non-ferrous metal metallurgy).

Application areas: Rare earth metallurgy and non-ferrous metal hydrometallurgy.

Corresponding products: uranium extractant, thorium extractant, rare earth (lanthanide) extraction and separation agent, zirconium/hafnium separation and extraction agent, cobalt/nickel separation and extraction agent, zinc extractant, copper extractant, vanadium extractant, precious metal recovery extractant, amine extractant, etc.

Why it works for this purpose: The secondary amine nitrogen atom of Bis(2-ethylhexyl)amine is protonated in an acidic aqueous phase to form R2NH2+ ammonium cations. These cations combine with metal complex anions (such as uranyl sulfate complex ions, chloride/thiocyanate complex anions of rare earth and cobalt nickel) through anion exchange/ion association to form neutral extractants soluble in the organic phase, thus achieving selective liquid-liquid extraction of metals. By adjusting the acidity of the aqueous phase, back-extraction and regeneration can be achieved, allowing for recycling. This is the key extraction chemistry basis for separating and purifying uranium, thorium, rare earth and non-ferrous metals.

2. Ore flotation collectors (mineral processing field)

Application areas: Non-ferrous metal beneficiation and mineral processing.

Corresponding products: flotation collectors for copper ore, flotation collectors for lead-zinc ore, flotation collectors for molybdenum ore, flotation collectors for copper oxide/zinc oxide ore, flotation collectors for potash (potassium magnesium salt) ore, and reverse flotation collectors for gangue such as quartz, etc.

Why it works for this purpose: Amines ionize in water to produce R2NH2+ cations, which are electrostatically adsorbed onto the negatively charged mineral surface, modifying the hydrophilic mineral surface to hydrophobic, causing the mineral particles to adhere to the bubbles and float, thus achieving the flotation separation of useful minerals and gangue; the two hydrophobic long chains enhance the hydrophobic spreading ability of the collector on the mineral particle surface, which is a typical cationic flotation collector structure.

3. Rust and corrosion inhibitors in metalworking fluids (core application in machining).

Application areas: Metal cutting, grinding and forming processes.

Corresponding products: cutting fluid, grinding fluid, tapping oil, drawing oil, stamping oil, rust-preventive emulsified oil, metalworking cleaning agent, machine tool guideway oil additive, etc.

Why it works for this purpose: The lone pair electrons of the nitrogen atom of amine adsorb onto the metal surface, forming a dense hydrophobic protective film that blocks water, oxygen, and corrosive media; its alkalinity can neutralize acidic substances generated in the processing environment (such as acids produced by chloride hydrolysis and rancidity products of oil oxidation), preventing rust on workpieces, tools, and machine tools during processing and storage between processes. It is a common rust-preventing and corrosion-inhibiting component in both water-based and oil-based metalworking fluid systems.

4. Rust-preventive oils, rust-preventive greases, and vapor phase rust inhibitors (core applications in metal protection and storage/transportation).

Application areas: Rust prevention packaging and warehousing and transportation of metal products.

Corresponding products: rust-preventive oil, rust-preventive grease, thin-film rust-preventive oil, displacement-type rust-preventive oil, vapor phase rust inhibitor (VCI), rust-preventive packaging paper and rust-preventive film, rust inhibitors for automotive parts, rust-preventive oils for bearings and precision parts, corrosion inhibitors for rust-preventive packaging of export machinery, etc.

Why it works for this purpose: Amine adsorption forms a film, creating a hydrophobic molecular film on the metal surface, cutting off the contact pathway between water and oxygen; its volatile amine molecules can fill the sealed packaging space and redeposit on the metal surface, achieving "vapor phase rust prevention" without the need for direct coating. It is particularly suitable for rust protection of precision parts with complex structures that are difficult to directly apply oil to, as well as equipment for long-term storage and export.

5. Corrosion inhibitors for industrial circulating water and boiler water treatment (water treatment field)

Application areas: Industrial water treatment and thermal systems.

Corrosion inhibitors for circulating cooling water, boiler water treatment agents, steam condensate system corrosion inhibitors, oilfield water injection corrosion inhibitors, acid pickling corrosion inhibitors, oil and gas pipeline corrosion inhibitors, and tank inner wall corrosion inhibitors, etc.

Why it can be used for this purpose: Amines adsorb and form films on metal surfaces, inhibiting the cathodic/anodic reactions of electrochemical corrosion, while neutralizing acidic components in water and systems (dissolving carbon dioxide, hydrogen sulfide, organic acids). It is particularly suitable for corrosion protection of oilfield water injection systems, condensate pipelines and pickling processes containing acidic corrosive media.

6. Detergent and dispersant additives for lubricating oils and greases (core application in the petroleum additives field)

Application areas: Lubricating oil and grease industry.

Corresponding products: Ashless cleaning and dispersing agent for internal combustion engine oil (succinimide dispersant, synthesized by imidization of Bis(2-ethylhexyl)amine and polyisobutylene succinic anhydride PIBSA), gear oil additives, hydraulic oil additives, lubricating grease additives, marine engine oil additives, natural gas engine oil additives, metalworking oil additives, etc.

Why it works for this purpose: Bis(2-ethylhexyl)amine is the key amine source for synthesizing ashless dispersants of the succinimide class. Its NH bond undergoes imidization with alkenyl succinic anhydride to generate a dispersant molecule with a "polar head group + long chain tail". The basic amine group neutralizes the acidic products produced by oil oxidation, and the long chain disperses and suspends sludge and carbon deposit precursors in the oil to prevent deposition. It also provides rust prevention and corrosion resistance, which is the basis for the US EPA's chemical data report to explicitly list the processing department of this product as "manufacturing of petroleum lubricating oils and greases".

7. Fuel detergency, dispersancy and corrosion inhibitors (fuel additives field)

Application areas: automotive fuels and fuel additives.

Corresponding products: gasoline detergents, diesel detergents, fuel dispersants, fuel corrosion/rust inhibitors, cetane number improvers (nitrate esters) intermediates, jet fuel additives, marine fuel additives, ethanol gasoline corrosion inhibitors, etc.

Why it works for this purpose: Amine detergents can remove and disperse carbon deposits on engine fuel injectors and intake valves, restore atomization and combustion efficiency, and reduce emissions; alkaline amines neutralize acidic components generated during fuel storage and combustion, prevent corrosion of fuel pipelines, storage tanks and engine fuel supply systems, and also serve as a multi-functional additive for cleaning, dispersing and preventing rust and corrosion in fuel systems.

8. Cationic surfactant and emulsifier intermediates (surfactant industry)

Application areas: Surfactants and industrial auxiliaries.

Corresponding products: quaternary ammonium salt cationic surfactant intermediates, metal cleaning agent surfactants, pesticide emulsifiers, asphalt emulsifiers, water-in-oil/oil-in-water industrial emulsifiers, textile softeners and antistatic agents, leather fatliquoring emulsifiers, paper deinking agents and sizing agent additives, oilfield demulsifier components, etc.

Why it can be used for this purpose: Bis(2-ethylhexyl)amine has an amphiphilic structure of "basic nitrogen head group + two hydrophobic alkyl chains". After quaternization or salt formation, it becomes a typical cationic surfactant. It can significantly reduce the interfacial tension between oil and water, stabilize emulsions, and impart softness and antistatic properties to fabrics. It is a common intermediate for a variety of industrial emulsifiers and cationic surfactants.

9. Quaternary ammonium salt disinfectants and phase transfer catalyst intermediates (fine chemical and disinfection/hygiene fields)

Application areas: disinfection and hygiene, and fine catalysis.

Corresponding products: intermediates for double-chain quaternary ammonium salt disinfectants, raw materials for bactericides used in surface disinfection wipes, intermediates for active ingredients in household and clothing disinfectants, raw materials for instrument disinfectants, raw materials for disinfectants for aquaculture and livestock environments, bactericides and algaecides for industrial circulating water, phase transfer catalysts, bis(2-ethylhexyl)dimethyl quaternary ammonium salts, etc.

Why it can be used in this way: Quaternary ammonium salts, which are formed by the quaternization of secondary amines, have positively charged nitrogen-head groups that electrostatically adsorb negatively charged microbial cell membranes and destroy the membrane structure, causing leakage of contents and thus killing bacteria. The double long-chain structure gives it stronger lipophilicity, penetrability and bactericidal activity. At the same time, long-chain quaternary ammonium salts also have the ability to catalyze phase transfer between oil and water phases, which can bring aqueous ionic species into the organic phase to promote the reaction. It is an important bifunctional intermediate in fine chemicals.

10. Rubber additive intermediates (rubber industry sector)

Application areas: Rubber processing and additives industry.

Corresponding products: rubber vulcanization accelerator intermediates (dithiocarbamate accelerator precursors), rubber antioxidant intermediates, rubber vulcanizing agent intermediates, tire and rubber product processing aids, rubber dispersants, etc.

Why it can be used for this purpose: Secondary amines can add with carbon disulfide to form dithiocarbamate vulcanization accelerator precursors, and condense with phenols and aldehydes to form antioxidants. By adjusting the vulcanization speed, crosslinking density and resistance to thermo-oxidative aging of rubber, it can improve the processability and service life of rubber products such as tires, hoses and seals.

11 . Dye and Pigment Intermediates (Dye Industry Sector)

Application areas: Dye and pigment industry.

Corresponding products: oil-soluble/solvent dye intermediates, disperse dye intermediates, metal complex dye ligand amines, pigment surface treatment agents, pigment dispersing aids, amines for ink colorants, etc.

Why it can be used in this way: Long-chain secondary amines are introduced into dye molecules as solubilizing groups, which improve the solubility and dispersibility of dyes in oily media, resins and ink systems; their nitrogen atoms can participate in complexation and color development as coordinating groups of metal complex dyes, and are commonly used amine intermediates in the synthesis of oil-soluble dyes and metal complex dyes.

Summary: Bis(2-ethylhexyl)amine (C16H35N, CAS 106-20-7, molecular weight 241.46) is a multifunctional industrial-grade long-chain secondary amine chemical used in automotive fuel additives, machine tool cutting fluids , and metal rust-preventive packaging. With its three main mechanisms of action—basic nitrogen-based matrix cationicization, bihydrophobic long-chain film-forming/interfacial activity, and NH4 bond derivatization—it has mature applications in rare metal hydrometallurgical extraction, ore flotation collection, metalworking fluid rust prevention, rust-preventive oils and vapor phase rust prevention, industrial water treatment corrosion inhibition, lubricating oil detergency and dispersion, fuel detergency and corrosion prevention, cationic surfactants and emulsifiers, quaternary ammonium salt disinfection and phase transfer catalysis, pesticide intermediates, rubber additives, and dyes and pigments. Hydrometallurgical extractants and petroleum detergency and dispersant intermediates are its two core applications in high-end industrial fields. This product is an industrial raw material and intermediate, not directly marketed to consumers.