UOP 987 Determination of Low Trace Sulfur in Liquid Hydrocarbons by Oxidative Combustion with Ultraviolet Fluorescence Detection

UOP 987 defines two standard methods for detecting low sulfur concentrations in highly volatile liquid hydrocarbons such as pentane isomers and diethyl ether. 

The first method described (A) is suitable for analysis of concentrations in the range of 10 to 1500 ng/g total sulfur (S). It relies on high-temperature combustion of the liquid samples in an oxygen stream. During this, the sulfur in the sample is converted to sulfur dioxide, which is then quantified with UV fluorescence. For dosing the samples, an autosampler with active cooling for the dosing syringe and sample tray is essential to ensure correct measurement results. For samples with a very low sulfur content of 10 to 200 ng/g, the standard furthermore describes a trap & release method (B) to concentrate the sulfur dioxide formed during combustion. This is recommended especially if the detection system used has a low sensitivity.

For less volatile samples and higher sulfur concentrations, ASTM D5453 and ASTM D7183 are more suitable. 

Highly volatile hydrocarbons play an important role in the petrochemical industry, in the production of solvents and fine chemicals. However, hydrocarbons are also feedstock materials in the synthesis of more complex products such as polymers. Whether feedstock, intermediate product or end product, strict quality control is required throughout the entire production process. Even the slightest traces of sulfur compounds can poison catalysts. This drastically impacts not only process efficiency, but also the service life of catalyst beds and quality of the end products.

With the multi EA 5100 and compEAct series, Analytik Jena offers highly sensitive analyzers for determination of trace sulfur in compliance with UOP 987 A.

Our solutions for UOP 987

Sources

• Low Trace Sulfur in Liquid Hydrocarbons by Oxidative Combustion with Ultraviolet Fluorescence Detection (ASTM.org)
• Elementaranalysator der Spitzenklasse - multi EA 5100 (analytica-world.com)