Synthesis technology for high-purity ethanolamine aminocarboxylic chelating agent

The invention relates to a synthesis technology for a high-purity ethanolamine aminocarboxylic chelating agent. The synthesis technology comprises the following steps: first, ethanolamine and water are mixed, the temperature is kept at 30-60 DEG G, formaldehyde and a sodium cyanide solution are dripped in the mixed solution slowly, and at the same time, nitrogen is blown into the mixed solution and ammonia gas is discharged; second, after dripping is finished, the temperature of the system is risen to 90-100 DEG C, thermal insulation is carried out for 1-2h, nitrogen is input, the ammonia gas is discharged continuously until thermal insulation is over; third, the solution obtained from the second step is subjected to decoloring and filtering, then the pH of the solution is adjusted to 2-5 by utilization of acid, and crystallization is carried out at a temperature of 30-60 DEG C. The synthesis technology can lower the NTA content effectively, raises the operation safety, raises the yield, shortens reaction steps and time, and lowers the reaction cost.