Method for producing citrate by using microchannel reactor

The invention provides a method for producing citrate by using a microchannel reactor. The method comprises the following steps: dissolving citric acid in alcohol to obtain citric acid alcohol liquor; heating a catalyst column to a constant temperature; introducing the citric acid alcohol liquor to the microchannel reactor (1), wherein the citric acid alcohol liquor passes through the catalyst column at a constant flow rate; and collecting a catalyst column effluent to obtain the citrate. The method is simple in process, can continuously produce citrate, has high operating safety and high selectivity, and is small in reaction volume and short in time. The catalyst can be repeatedly used, and the equipment is hardly corroded. Meanwhile, as no water carrying agents are used, the esterification rate is over 96% by means of such characteristics of the microchannel reactor as efficient heat mass transfer capacity and easiness in direct amplification. The product has high quality and the energy consumption is low, so that the method is an environment-friendly and efficient method for synthesizing citrate.