Question

preparation for hexamethylene tetramine

Answer 1

Hexamethylenetetramine is prepared by the condensation of formaldehyde and ammonia:

Preparation of hexamine (hexamethylenetetramine, urotropine)

473 g of a 38 % formaldehyde solution, is treated with 700 g of 20% ammonium hydroxide solution, until the solution is slightly alkaline. The mixture is allowed to stand, for several hours and if necessary more ammonia being added. The solution is filtered and then evaporated in vacuum to a thick paste. The hexamine crystals are filtered off washed with ethyl alcohol, and dried. To obtain pure hexamine it is recrystallized from water or alcohol. Hexamine forms colorless, odorless crystals, which are soluble in water, and 90 % alcohol. It does not melt on heating, but sublimes at a temperature of about 260° C.