Undirbúningur píperasín

The preparation method is based on chloroethanol as raw material, ammoniated and cyclized. The process is to heat chloroethanol and ammonium hydroxide in the autoclave to ammonia pressure of 441 kPa, stirring reaction for 5h, atmospheric pressure recovery of excess ammonium hydroxide to aminoethanol aqueous solution. Mixed with quantitative hydrochloric acid, concentrated into semi-paste-like ethanolamine hydrochloride concentrate under reduced pressure, heated to 150 degree , added paraffin, melted in advance, and then heated to 260 degree , kept at (260±2) degree for 12h, discharged and filtered, paraffin removed, piperazine hydrochloride was obtained. Piperazine hydrochloride, solid sodium hydroxide and water were added to the reactor, stirred for 1.5h, discharged ammonia, and then heated to 130~140 degree , steam out piperazine hexahydrate solution, filter the residue, freeze the solution to 8 degree , centrifugate and filter to obtain piperazine hexahydrate, and dehydrate piperazine hexahydrate to obtain piperazine product. Reaction equation :ClCH2CH2OH+NH4OH→NH2CH2CH2OH·HCl+H2O