Preparation method of piperazine synthesis catalyst

The invention discloses a preparation method of a piperazine synthesis catalyst and the method is used for solving the problem that in the prior art, piperazine is poor in selectivity and the yield ratio of piperazine and triethylene diamine is low. An impregnation method is adopted for the catalyst and the preparation method is as follows: with an HZSM-5 molecular screen as a carrier, adding the carrier into an impregnating liquid containing Na and Mg , standing, dehydrating, forming, drying and carrying out calcination to prepare the piperazine catalyst. When the catalyst is applied in a fixed bed continuous catalytic piperazine synthesis reaction with ethylenediamine, the selectivity is greater than 95% and the yield ratio of piperazine and triethylene diamine is greater than 15.