MDEA (Methyl Diethanolamine)

Methyldiethanolamine (MDEA, N-methyldiethanolamine, C5H13NO2, CAS 105-59-9) is the tertiary amine used for selective acid-gas removal. Global Chemicals LLC supplies it at 99.5% minimum purity as a clear, colourless to pale-yellow liquid with a molecular weight of 119.16 g/mol, boiling point 247 °C and specific gravity 1.042 at 20 °C, in 200 L drums, 1,000 L IBCs, ISO tanks and bulk, from stock in Muscat for plant make-up and fresh fills.

Why MDEA rather than MEA or DEA. As a tertiary amine it does not form a carbamate with CO2, so it absorbs H2S fast and CO2 slowly. Run at a 40–50% solution with the right contact time, a gas-sweetening unit removes H2S to pipeline or LNG specification while leaving much of the CO2 in the gas, which keeps the solvent circulation, reboiler duty and regeneration energy well below those of primary and secondary amines. The same chemistry gives low corrosion, which allows carbon-steel equipment, and low degradation, so solvent losses are small and reclaiming is rare. Where bulk CO2 removal is wanted instead, MDEA activated with piperazine takes CO2 quickly while keeping the low regeneration energy.

Where it runs in Oman: sour-gas sweetening units feeding Oman LNG and the gas grid, selective treating of refinery and syngas streams, hydrogen purification, Claus-unit tail-gas treating, and CO2 capture for enhanced oil recovery. Typical operation is a 40–50% aqueous solution; our team supplies the data sheet with vapour pressure, viscosity and loading curves for solution design, and the product carries a certificate of analysis giving purity, water content and colour.

Handling: MDEA is combustible with a high flash point, hygroscopic and mildly alkaline; store it in closed carbon-steel or stainless tanks under a nitrogen blanket where possible, away from acids and oxidisers, and wear gloves and goggles when transferring. Keep oxygen out of the circulating solution to limit degradation and heat-stable salt formation.

Delivery is same day within Muscat, next day to Sohar, Salalah and Duqm, to Fahud and the interior gas plants by arrangement, and by road across the GCC with a certificate of origin. Global Chemicals LLC is JSRS-registered and ISO 9001:2015 certified. Request a quote with the quantity, pack type and delivery schedule.