METHOD OF PREPARING DEMULSIFIER FOR DEHYDRATION AND DESALTING OF OIL EMULSIONS Russian patent published in 2007 - IPC C10G33/04 C08G18/09 C08G18/48 

FIELD: crude oil treatment.

SUBSTANCE: demulsifier useful for destroying oil emulsions on crude oil treatment plants is prepared through polyether-tolylene diisocyanate reaction. In particular, tolylene diisocyanate dimer is used at polyether-to-tolylene diisocyanate dimer molar ratio between (n+1):0.5n and (n+3):0.5n, wherein n is integer from 1 to 6 and represents number of tolylene diisocyanate moles. Reaction is conducted at 20-25°C, after which temperature is raised to 50-60°C. Advantageously, demulsifier is dissolved in organic solvent, e.g. aromatic or non-aromatic water-soluble solvent, to concentration 30-65%.

EFFECT: increased demulsification activity of demulsifier and improved environmental characteristics of demulsifier preparation process.

2 cl, 2 tbl, 28 ex