Identification of the Products of the Reaction between Sulfur and Sodium Carbonate.

The reaction between sulfur and sodium carbonate at 350 °C has been investigated, and the products of the reaction have been identified at room temperature by using IR and Raman spectroscopies. The reaction is a disproportionation of sulfur in sodium thiosulfate (oxidized species) and in a polysulfide (reduced species). When sodium carbonate is in excess ([S]/[Na2CO3] < 3.3) only one polysulfide, S42-, is formed, but when sulfur is in excess, only S52- is observed.