How to Find Total Percentage of Sulfur within a Sample
Sulfur Determination via Schoniger Combustion
Atomic weight 32.06, Atomic Number 16, Melting Point 115.21 C, Boiling Point 444.67 C.
The solid sample is weighed into ashless paper and inserted into custom made Platinum stopper. The stopper is fitted it a flask that is charged with the appropriate reactants and oxygen. On combustion the sulfur present is oxidized from SO2 to SO3. The resulting liquid is then removed and titrated. With an indicator the color change is gold to pink. In cases with high levels of fluorine, it is best to add Boric acid.
The most common standard for this determination is Cystine available through the NIST. Other standards are used for specific circumstances.
The preceding is a brief description of our techniques used in sulfur determination. Due to the exclusive use of the flask combustion in the sulfur determination, we are not able to determine sulfur on air-sensitive samples.
Interferences: include Cu, F, I, Na, P, Se, and Sn.
Please note the interferences above which cannot be circumvented during analysis which may then cause irregular results. Please note irregular results due to interferences cannot be interpreted by the chemists. Midwest Microlab chemists will perform requested analysis, and report results as found with the understanding that the submitter understood the interferences associated and how it may affect results.
For more information on Sulfur analysis performed at Midwest Microlab please click on the following link: Midwest Microlab Contact Information