Features of Interaction in the Sulfur(IV) Oxide–Hexamethylenetetramine–Water System: A First Example of Identification of the Product with a Sulfur–Carbon Bond

Abstract

Hexamethylenetetramine (HMTA) is a ligand in the synthesis of coordination compounds and also is used as a pharmaceutical antiseptic drug and as hexogen precursor. An attempt is known to use aqueous solutions of HMTA as an absorbent for extracting hydrogen fluoride and sulfur dioxide from the flue gases of aluminum production. In the study on the interaction in the HMTA–H2SO3–H2O system a formation was found of compounds 2HMTA·H2SO3·6H2O and HMTA·2H2SO3·8H2O, the hexamethylenetetrammonium sulfite and bisulfite, respectively, hydrated forms. On the other hand, in acidic solutions HMTA is prone to hydrolysis to form ammonia and formaldehyde that does not exclude further deeper chemical reactions in the system HMTA–H2SO3–H2O (HMTA–SO2–H2O), as indicates indirectly the formation of Н2NCH2SO3Na in the reaction of sodium hydrosulfite with formaldehyde and ammonia.