This invention relates to a process for the treatment of the reaction mass produced during the joint elimination of barium-containing nitrite-/nitrate-bearing carburizing salt wastes and cyanide-/cyanate-bearing wastes by ignition of the dry mixture at elevated temperatures, comprising suspending the reaction mass in water and either (a) adding a water-soluble barium salt to the aqueous suspension in equimolar quantities, based upon carbonate ions, and separating precipitated barium carbonate, or (b) freeing the alkaline suspension from barium carbonate by filtration, reacting the filtrate with a water-soluble calcium salt, and separating precipitated calcium carbonate, concentrating the clear solutions obtained according to (a) or (b) to a water content of 10-20% by weight, separating precipitated sodium chloride, and evaporating the residual solution to dryness.