Method for preparing polyether polyol based on micro-mixer and micro-channel reactor

The invention relates to a method for preparing polyether polyol based on a micromixer and a microchannel reactor, which comprises the following steps: mixing an initiator and a catalyst in different proportions to obtain a mixture; premixing the obtained mixture with an olefin oxide monomer through a T-type mixer or by using an SIMHEX-HC mixer, feeding the mixture into a microreactor, and continuously carrying out polymerization reaction to obtain polyether polyol; after the reaction is finished, obtaining crude polyether polyol; after the crude polyether polyol enters cation exchange resin, small molecules are removed, and a polyether polyol product is obtained. According to the invention, the reaction temperature is reduced, and the reaction temperature is lower than 130 DEG C; the catalyst of the reaction system is sodium hydride, and the generated gas by-product is easier to remove, so that the influence on the reaction system is reduced. The reaction is a continuous flow reaction, the reaction time is s