Mercaptans and Hydrogen Sulphide in Crude Oil as per ASTM D3227 and UOP163

In the refining process of crude oil, sulphur compounds are present throughout the entire boiling range of the hydrocarbons. In order to prevent corrosion of pipes and meet the specifications for the final products, various desulphurisation treatments are used. The 2045TI Ex-proof online Analyser from Metrohm Process Analytics is a turn-key solution to monitor the sulphur content at any stage in the downstream process.

Desulphurisation can occur at many points within a refinery, from the crude feedstock to the distillate streams. While lighter impurities (including mercaptans and sulphides) can be removed via hydrotreating, heavier sulphur compounds can be removed with hydrocracking after the hydrotreating process. The mercaptan and H2S content in crude oil is determined by a 2 endpoint argentometric titration (see also Metrohm Application Bulletin 135) based on ASTM D3227-83 and UOP163-67. Application Note AN-PAN-1026 describes the respective applications and is available free from Metrohm Process Analytics.

The Process Analytics 2045TI Ex-proof Process Analyser with a customised sample preconditioning system can be implemented in many areas within the refinery to ensure the catalysts in the reactors are not exhausted and to limit corrosion further on in the distillation unit. The analyser fulfils EU Directives 94/9/EC (ATEX95) and is certified for Zone-1 and Zone-2 areas.