N-Methylethanolamine CAS 109-83-1

What is N-Methylethanolamine?

N-Methylethanolamine is a secondary alkanolamine — a methyl group and a hydroxyethyl arm on the same nitrogen, CH₃NHCH₂CH₂OH. It sits between methylamine and monoethanolamine in a structural sense, and borrows useful properties from both.

It is a clear, colourless liquid boiling at about 159 °C with a mild ammoniacal odour, freezing below zero and fully miscible with water. The flash point is near 73 °C, so it is combustible rather than flammable and handles comfortably in ordinary drums and pumps.

Chemically it offers one reactive N-H and one primary hydroxyl, which is a genuinely useful combination: the two can be addressed separately, and the molecule introduces an N-methyl-N-hydroxyethyl fragment in a single step that would otherwise take two. That is mostly why it is bought — as a building block rather than as a bulk functional chemical.

Commercially, NMEA is a fine chemical intermediate with a broad spread of smaller markets: pharmaceutical and agrochemical synthesis, surfactant and emulsifier intermediates, corrosion inhibitors, dye and photographic chemistry, and gas treating where its particular balance of basicity and capacity suits the duty.

Why N-methylethanolamine specifically

• Introduces a disubstituted nitrogen in one step. The N-methyl-N-hydroxyethyl fragment arrives complete, avoiding the selectivity problems of alkylating a primary amine twice.
• One N-H and one hydroxyl. The two functional groups can be addressed independently — acylation at the nitrogen, esterification or alkoxylation at the oxygen.
• No over-alkylation risk. Unlike a primary amine it cannot react twice at nitrogen, which keeps acylation and substitution chemistry clean.
• Convenient handling. Liquid across the normal temperature range, combustible rather than flammable, and fully water-miscible.

How NMEA is Manufactured

N-Methylethanolamine is made by ethoxylating methylamine, or by methylating monoethanolamine. Either route produces the over-substituted product alongside it.

• Ethoxylation of methylamine. Aqueous methylamine is reacted with ethylene oxide. The reaction is exothermic and does not stop cleanly at the mono-hydroxyethyl stage — the NMEA formed competes for the next molecule of ethylene oxide to give methyl diethanolamine.
• Ratio control. A substantial excess of methylamine favours the mono-adduct. The excess is stripped and recycled, which is the energy-intensive part of the process.
• Alternative methylation route. Monoethanolamine can instead be methylated with methanol or formaldehyde and hydrogen over a catalyst, which leaves a different trace profile — residual MEA and dimethylated product rather than methyl diethanolamine.
• Separation and finishing. The product is separated by vacuum distillation and taken to specification, then filled with nitrogen blanketing where colour and water matter.

Typical Commercial Specification

Figures below are representative of standard commercial grade. Pharmaceutical and low-colour grades with tighter limits are available — send us the specification you work to and we will quote against it.

Physical & Chemical Properties

Reactivity in practice

One N-H and one hydroxyl, addressable separately. That is the whole functional description and the reason it is bought:

• Acylation and amidation at the nitrogen. Reaction with acid chlorides, anhydrides and esters gives N-methyl-N-hydroxyethyl amides used across pharmaceutical and agrochemical synthesis.
• Esterification and alkoxylation at the hydroxyl. The primary alcohol esterifies and reacts with ethylene oxide, giving surfactant and emulsifier intermediates from the other end of the molecule.
• Substitution on activated systems. Displaces halide from activated aromatics and heterocycles to install the methylaminoethanol group.
• Acid gas absorption. As a secondary amine it forms a carbamate with carbon dioxide and takes up hydrogen sulphide, used in some gas treating formulations.

NMEA vs DMEA, DEEA and MEA

The substituted ethanolamines are all built from an amine plus ethylene oxide, and they differ in how many alkyl groups sit on the nitrogen and how many hydroxyethyl arms. That count decides three things at once: how basic the molecule is, whether it still has an N-H, and how volatile it is — and those three between them determine almost every application.

Stated plainly: NMEA keeps one N-H, so it is a building block that gets incorporated into products and carries the nitrosamine consideration common to secondary amines. DMEA and DEEA have none, so they act as catalysts and bases rather than becoming part of the product — and the practical choice between those two usually comes down to volatility, with DMEA flashing off faster and DEEA persisting further into a system. MEA sits apart as the primary amine with two reactive hydrogens and the chemistry that follows from them.

Industries We Supply NMEA To

The same molecule leaves our warehouse for very different factories. What changes between them is not the CAS number but the grade — MDEA carry-over and colour in particular — and the documentation each sector expects.

Where NMEA is Used

NMEA is a building block across a broad set of smaller markets rather than a bulk commodity. These are the end uses our customers buy it for.

In pharmaceutical synthesis

The value here is step economy. Building an N-methyl-N-hydroxyethyl nitrogen from a primary amine means two alkylations with a selectivity problem at each — the mono-substituted product is more nucleophilic than the starting material, so it tends to react again before the first alkylation is complete. NMEA arrives with that nitrogen already built, which removes the problem entirely. API producers run tight specifications on MDEA carry-over, residual MEA, colour and metals, all of which have to clear ICH limits.

In agrochemical intermediates

The methylaminoethanol group appears across crop protection chemistry, both as a substituent and as a handle for further elaboration through the hydroxyl. Plants running registered actives care about consistency of the amine distribution, since MDEA carry-over is inert at the nitrogen and reduces effective charge without producing an obvious off-spec result.

In surfactant chemistry

NMEA can be built from either end. Acylating the nitrogen with a fatty acid gives an N-methyl amide with a free hydroxyl for further reaction; alkoxylating the hydroxyl gives a chain while leaving the amine available. That flexibility suits specialty amphoteric and cationic surfactant routes, where colour is a live specification because it carries through to the finished product.

In gas treating

As a secondary amine NMEA forms a carbamate with carbon dioxide and absorbs hydrogen sulphide by proton transfer. It appears in some formulated solvent blends where its particular combination of basicity, capacity and degradation behaviour fits the duty better than a standard ethanolamine. Iron and chloride specifications matter here for the usual reasons in a hot amine circuit.

Quality Control & Testing

Every lot is released against a batch-specific Certificate of Analysis. The methods behind the numbers are standard across the industry, and we are happy to share them or to work to your own in-house test protocol.

• Assay and amine distribution — gas chromatography, quantifying methyl diethanolamine, monoethanolamine and residual methylamine alongside the main component.
• Water content — Karl Fischer titration. NMEA is hygroscopic and drifts once a drum is opened, and water matters directly in acid-chloride chemistry.
• Colour — APHA / Hazen against a standard. The alkanolamines darken on air contact, and colour carries into surfactant and dye products.
• Distillation range — a fast, revealing check for MDEA and moisture carry-over before any instrument confirms it.
• Amine value — total and secondary amine value by titration, which distinguishes active NMEA from inert MDEA carry-over.
• Metals and residue — iron and evaporation residue, both of which matter in pharmaceutical and gas-treating service.

Common Process Problems & Likely Causes

When NMEA misbehaves in a plant, the cause is usually one of a short list of things. This table is the shortcut our technical desk works through before anyone opens a complaint file.

Packaging, Storage & Shipping

• Standard packing. 190 kg net in lined steel or HDPE drums, with 1000 L IBCs for larger users.
• Bulk packing. Road tankers and ISO tank containers for continuous users.
• Storage. Cool, dry, well-ventilated and bunded, with containers tightly closed and protected from air and moisture.
• Nitrite segregation. As a secondary amine, NMEA should be stored and handled away from nitrites and other nitrosating agents.
• Materials of construction. Stainless steel or suitable lined vessels. Carbon steel is used in some service but corrodes more readily when the amine is hot or loaded with acid gas. Avoid copper, brass, bronze and aluminium.
• Oxygen exclusion. The ethanolamines oxidise and darken on air contact, particularly when warm. Nitrogen blanketing is standard for colour-sensitive grades and for any heated storage.
• Shelf life. Typically 12 months in unopened original packing under those conditions. Beyond that, re-test rather than assume.
• Transport classification. Typically UN 2735, Amines, liquid, corrosive, n.o.s., Class 8. Confirm the entry and packing group against the current SDS and the shipper's declaration for your destination and mode.

Hazards & Safe Handling

N-Methylethanolamine is corrosive and a secondary amine with an associated nitrosamine consideration. It must be handled by trained personnel under a proper risk assessment. The classifications below are indicative — the current SDS supplied with your consignment is the governing document.

• Nitrosamine consideration. As a secondary amine, NMEA can be nitrosated in the presence of nitrosating agents. Keep nitrites out of the handling area, segregate in storage, and design formulations so the two cannot meet. Where the finished product falls under a nitrosamine limit scheme, assess this at the design stage.
• Exposure control. Handle under local exhaust ventilation or in a closed system. Vapour pressure is low at ambient, so skin and eye contact dominate — except where the material is heated or sprayed.
• PPE. Chemical-resistant gloves, chemical goggles and face shield, chemical-resistant clothing.
• Incompatibilities. Strong oxidising agents, strong acids, acid chlorides, nitrites, and copper, brass, bronze and aluminium equipment.
• Spill response. Contain, absorb with inert non-combustible material and collect in a labelled closed container. Ventilate. Do not wash to drain.
• Environment. Do not allow to enter drains, surface water or groundwater. Dispose through a licensed chemical waste contractor.
• Fire. Combustible. Use alcohol-resistant foam, dry chemical or carbon dioxide; cool exposed containers with water spray. Decomposition releases nitrogen oxides — use self-contained breathing apparatus.
• First aid. Remove contaminated clothing immediately, wash skin with plenty of water, flush eyes for at least 15 minutes, and seek medical attention with the SDS to hand.

Regulatory & Compliance Notes

N-Methylethanolamine is an established industrial chemical and is listed on the major national chemical inventories. Because obligations differ by territory, volume and use, the notes below are orientation rather than legal advice — confirm your own position with your regulatory adviser before importing.

• Inventory status. Listed on the principal chemical inventories in the major importing regions. Ask us for the inventory confirmation relevant to your destination country.
• Import registration. Several territories require the importer to hold a registration or notification before a consignment lands. Start that process early — it is the most common cause of delay at destination.
• Hazard communication. Supplied with an SDS compliant with the format applicable to your region, and labelled in line with the GHS classification for the product.
• Nitrosamine controls. As a secondary amine, NMEA falls within the scope of nitrosatable-amine restrictions that apply in cosmetics, metalworking fluids and some other sectors. Confirm the position for your product category at destination.
• Dangerous goods. Typically UN 2735, Amines, liquid, corrosive, n.o.s., Class 8. Because this is a generic entry, confirm the classification and packing group against the current SDS; declarations prepared for IMDG (sea) or IATA (air) as appropriate.
• Workplace exposure. Occupational exposure limits apply in several jurisdictions. Set your controls against the limit in force where the material will be handled.

We Supply NMEA Worldwide

Chelora Chemicals is a supplier and export partner, not a single-plant trader. We ship N-Methylethanolamine from India to customers across Asia, Europe, the Middle East, Africa, and North and South America, handling the export documentation, dangerous-goods paperwork and freight so the material arrives ready to use.

• Incoterms. EXW, FOB, CIF, CFR and DAP quoted to suit your purchasing terms and freight arrangements.
• Ports. Regular shipments through Nhava Sheva (JNPT) and Mundra, with other Indian ports arranged where it suits the routing.
• Documentation. Commercial invoice, packing list, certificate of origin, COA, SDS and dangerous-goods declaration issued as a complete set.
• Flexible volumes. A single drum for laboratory qualification, through LCL consolidations, up to repeat full loads on a supply contract.
• Supply continuity. Because we are independent of any one producer, a plant turnaround or a shipping disruption at one source does not have to become your stock-out.

Buying NMEA from Chelora

We are an independent sourcing and supply partner. For NMEA that means knowing which production route the material came from, because the impurity that matters differs between them — methyl diethanolamine from the ethoxylation route, residual MEA from the methylation route, and the two cause opposite problems downstream.

• Documentation on every lot. Batch-specific COA, current SDS and TDS issued with the consignment, not weeks afterward.
• Samples before commitment. Trial quantities for process qualification ahead of a commercial order.
• Quantities. From a single 190 kg drum through to tank loads and ongoing contract supply.
• Export experience. Class 8 dangerous-goods documentation, packing and labelling handled for sea and road freight.
• Technical support. Direct access to people who know the chemistry, for questions on amine value, production route or colour control.
• Related intermediates. MEA, DMEA, DEEA, methylamine and the wider alkanolamine range from one supplier.

How ordering works

• Send the enquiry. Product, grade or specification, quantity, destination port and the Incoterm you buy on. If you have a spec sheet, attach it — it saves a round trip.
• We quote. Price, lead time, packing and a sample COA, normally within one working day.
• Sample and qualify. For first orders or critical applications, we send a trial quantity so your lab can sign off before you commit.
• Confirm the order. Proforma invoice issued; payment terms agreed against the volume and the relationship.
• Production and QC. Material allocated and released against a batch-specific COA, with a pre-shipment sample where the application calls for it.
• Ship and document. Packed, labelled and loaded with the full export and dangerous-goods document set, and tracked through to arrival.

Related Alkanolamines & Intermediates

Buyers of NMEA usually source several of these alongside it. Consolidating them on one order cuts freight cost and gives you a single point of contact for documentation.