Method for inhibiting coking of ethylenediamine reaction solution

The invention discloses a method for inhibiting coking of ethylenediamine reaction solution. The method comprises the following steps of: adding an anti-coking agent into the ethylenediamine reaction solution, wherein the anti-coking agent is one or more of N,N-disec-butyl-p-phenylenediamine, phenylenediamine, dimethyl succinate, dimethyl glutarate and dimethyl adipate; mixing the anti-coking agent and the ethylenediamine reaction solution uniformly, wherein the weight ratio of the added anti-coking agent to the ethylenediamine reaction solution is (0.5-3): 100; adding the mixture to a kettlebottom of a rectification column, performing rectification, and obtaining water, ethylenediamine, piperazine, ethanolamine and triethylene diamine products in turn, wherein the final residue is mixture of high polymer and the anti-coking agent; and adding water, stirring, filtering, and separating out the anti-coking agent, wherein the anti-coking agent can be recycled. The anti-coking agent has the advantages of high eff