A study on error sources in an acid dissolution and steam distillation procedure for determination of nitrogen in steel

Abstract

Error sources in the digestion steam distillation procedure for the nitrogen analysis of steel were studied. When steel samples were dissolved in glass beakers, the results were affected by the adsorption of nitrogeneous compounds on the inner surface of beakers. This sort of adsorption was seen during the distillation procedure, whereby a fraction of distilled ammonia was adsorbed on the inner surfaces of the distillation flask and the condenser. Against these interference, beakers should be reserved in a vacuum desiccator or filled with distilled water, the distillation flask should be made of teflon, and the condenser should be as small as possible or the steam with distilled ammonia should be condensed directly in a modified receiver. Better results were obtained by these improvements.