- Method ASTM D3227
- Repeatability 0.00007+0.027x
- Reproducibility 0.00031+0.042x
- Blending linear
- Additive Correction Yes
The purpose of this test is to determine mercaptan sulfur in gasolines, kerosines, aviation turbine fuels, and distillate fuels containing from 0.0003 to 0.01 mass % of mercaptan sulfur. Organic sulfur compounds such as sulfides, disulfides, and thiophene, do not interfere. Elemental sulfur in amounts less than 0.0005 mass % does not interfere. Hydrogen sulfide will interfere if not removed. As stated in Copper and Silver corrosion methods the presence of these compounds can cause excessive corrosion of fuel system components and non-marketable odors.
The method is performed by introducing a weighted piece of sample to a titration cup full of solvent after h2s is removed (if present). The sample is then titrated using silver nitrate to react with the sulfur compounds. When complete the amount of titrant used is converted to a ppm or weight percent result and reported.