The utility model discloses a
system for synthesizing N, N-bis (2-ethoxyl) aminomethyl diethyl
phosphonate with low
formaldehyde content, which comprises a reaction kettle I and a reaction kettle II, the reaction kettle I and the reaction kettle II are jacketed reaction kettles, and the reaction kettle I and the reaction kettle II are respectively provided with a top feed port and a bottom
discharge port. A bottom
discharge port of the reaction kettle I is communicated with a top feed port of the reaction kettle II, a
reflux cooling
assembly is arranged at the top of the reaction kettle I, and a bottom
discharge port of the reaction kettle II is connected with a product
storage tank. After diethanol amine and
paraformaldehyde are reacted in a reaction kettle I, a water-carrying agent is added for azeotropic
reflux water separation so as to realize azeotropic separation of water generated in the reaction, so that the purpose of rapidly and efficiently preparing the MHPZ intermediate is achieved, excessive
formaldehyde is removed in the water-carrying process, and synthesis and preparation of N, N-bis (2-ethoxyl) aminomethyl diethyl
phosphonate with low
formaldehyde content are realized.