The invention discloses an environment-friendly multi-branched cationic polyether microbial
demulsifier synthesized based on a double
metal cyanide complex catalyst,
bisphenol A is used as a block polyether initiator and reacts with
formaldehyde and vinylamine to generate a
polyamine compound which takes
bisphenol A as a core, vinylamine as a
branch and phenolic hydroxyl as a leaf, then ring-opening
polymerization is performed on the modified cationic polyether and
epoxy compounds including epoxypropane and
ethylene oxide to obtain multi-branched polyether, and further the multi-branched polyether reacts with a
microbial metabolite and a surfactant to obtain the multi-branched cationic polyether microbial
demulsifier. The multi-branched cationic polyether microbial
demulsifier prepared by using the double-
metal cyanide complex catalyst has no acid-base property problem, has good chemical and biological characteristics and oil and water amphipathy, can effectively reduce the
surface tension of water, can be used under the conditions of
extreme temperature, pH value and
salinity, is non-toxic, environment-friendly and energy-saving, the demulsifier is biodegradable, has higher deoiling rate and demulsification efficiency and better demulsification capability, does not need post-treatment, and overcomes the defects of the traditional demulsifier in function and preparation process; the oil exploitation cost is reduced, and the development of an oil exploitation process is promoted.