Solutions Guide
Hexahydro-1,3,5-tris(2-hydroxyethyl)-s-triazine — CAS 4719-04-4
Hexahydro-1,3,5-tris(2-hydroxyethyl)-s-triazine (CAS 4719-04-4) is the IUPAC chemical name for the compound sold commercially as MEA Triazine 78%, the most widely used liquid hydrogen sulphide (H2S) scavenger in the oil and gas industry. This page explains what the molecule is, how it is formed, its physical properties, and the many synonyms under which it is bought and sold.
Last updated:
What is hexahydro-1,3,5-tris(2-hydroxyethyl)-s-triazine?
Hexahydro-1,3,5-tris(2-hydroxyethyl)-s-triazine is a water-soluble organic compound with CAS number 4719-04-4. It belongs to the hexahydrotriazine family and is the active ingredient in MEA Triazine 78%. In industrial use it functions as a non-regenerative H2S scavenger: it reacts irreversibly with hydrogen sulphide to form stable, water-soluble dithiazine by-products, removing toxic and corrosive H2S from gas and liquid hydrocarbon streams.
How the molecule is formed
The compound is produced by the condensation of monoethanolamine (MEA) with formaldehyde. Three molecules of monoethanolamine react with three of formaldehyde to build a six-membered hexahydrotriazine ring bearing three 2-hydroxyethyl groups. The finished product is a clear to pale-yellow liquid, typically supplied at 78% active concentration in water, with a mild amine odour and an alkaline pH of roughly 9 to 11.
Synonyms and trade references
The same molecule is referenced under many names across datasheets, customs records and supplier catalogues: MEA Triazine, monoethanolamine triazine, 1,3,5-triazine-1,3,5(2H,4H,6H)-triethanol, 1,3,5-tris(2-hydroxyethyl)hexahydro-1,3,5-triazine, triazinetriethanol and HHT. All share CAS 4719-04-4 and describe the same triazine-based H2S scavenger chemistry supplied by Vasudev Chemo Pharma as MEA Triazine 78%.
Frequently asked questions
Is hexahydro-1,3,5-tris(2-hydroxyethyl)-s-triazine the same as MEA Triazine?+
Yes. Hexahydro-1,3,5-tris(2-hydroxyethyl)-s-triazine is the IUPAC chemical name; MEA Triazine 78% is the commercial name for the same compound (CAS 4719-04-4) supplied at 78% active concentration.
What is the CAS number of hexahydro-1,3,5-tris(2-hydroxyethyl)-s-triazine?+
The CAS number is 4719-04-4. It is also referenced as monoethanolamine triazine and triazinetriethanol.
What is it used for?+
It is used as a hydrogen sulphide (H2S) scavenger in natural gas, crude oil, biogas and wastewater, converting toxic H2S into stable, water-soluble by-products.