Mercaptans are low molecular weight sulfur-containing organic compounds such as H2S, RSH, COS, and CS2 found in crude oil, petroleum fractions, gases, and gas condensates, and are considered one of the main environmental pollutants.
Mercaptans are a type of organic sulfide that are widely present in petroleum products and often lead to a decline in the quality of the final product. Therefore, the removal of sulfur compounds from petroleum hydrocarbons, known in the oil and gas industries as sweetening operations, is deemed an unavoidable necessity. Sweetening processes such as the Merox process and DMD/DMC processes are designed to separate sulfur-containing compounds (hydrogen sulfide and light mercaptans) using sodium hydroxide washing, organic-metallic catalysts, and oxygen injection.
In these processes, mercaptans are converted into disulfides. The catalyst used in these processes consists of organic-metallic compounds known as metal-phthalocyanines. The companies that own the licenses for the mercaptan removal process and the technical knowledge of this catalyst include UOP (MEROX catalyst), VNIIUS (IVKAZ catalyst), and AXENS (LCPS catalyst).
Among the aforementioned companies, UOP and AXENS have been unable to collaborate with Iran due to U.S. sanctions. However, through the efforts of representatives from the Artin Azma Mehr supply network, this company has successfully obtained exclusive representation from VNIIUS for supplying catalysts and providing technical engineering consulting services in the construction of DMD and DMC units in Iran.