PEP Review 83-3-3
Ethylene Glycol from Formaldehyde via Glycolaldehyde
Published: November 1984
This review examines the technology and economics of producing ethylene glycol from a C1 raw material, formaldehyde. Five different processes are reviewed briefly, and a preliminary flow sheet is shown for a process that hydroformylates formaldehyde to produce glycolaldehyde, which is hydrogenated to ethylene glycol. Hydroformylation is carried out in a liquid-phase reaction catalyzed by rhodium dicarbonyl acetylacetonate and a phosphine ligand. Catalyst solution is extracted from the reactor product, and the glycolaldehyde is hydrogenated over a nickel catalyst.
The economics of an integrated plant to make formaldehyde from methanol and convert the formaldehyde to glycolaldehyde and ethylene glycol have been evaluated. Product value of EG from this route is higher than the product value of EG made by the conventional route from ethylene via ethylene oxide. If the price of ethylene escalates more rapidly than the price of methanol, this could become an attractive process to develop for making EG.