反应详情

To an aqueous solution of perchloric acid, containing 200 g of said acid in 500 ml of water 40 % solution), the amount of aqueous solution of piperazine hexahydrate required for neutralization is added. The required amount of piperazine hexahydrate is 388.46 g (C4H10N2.6H2O) dissolved in 500 ml of water. Preferably the pH of the neutralizing solution is controlled to a pH close to 6. The piperazine perchlorate solution is mixed with the warm solution of p-dihydroxy benzene disulfonic acid potassium salt, and is stirred until a copious precipitate of potassium perchlorate is formed, which then increases when the solution is left to cool for several hours. After filtering off the potassium perchlorate, the solution of piperazine p-dihydroxy benzene disulfonate is concentrated in a rotary evaporator, under vacuum, at 60° C., until crystals begin to form, and it is then left in a refrigerator. The product is filtered and recrystallized in water to give 388 g of bis (piperazine) p-dihydroxy benzene disulfonate, having a melting point of 270° C.

1. additionis added
2. customa pH close to 6
3. customis formed
4. temperaturewhich then increases when the solution
5. waitis left
6. temperatureto cool for several hours
7. filtrationAfter filtering off the potassium perchlorate
8. concentrationthe solution of piperazine p-dihydroxy benzene disulfonate is concentrated in a rotary evaporator, under vacuum, at 60° C., until crystals
9. customto form
10. waitit is then left in a refrigerator
11. filtrationThe product is filtered
12. customrecrystallized in water