Formation of Sediments in Fuels Containing Added Sulphonic Acids

摘要

Catalytically cracked gas oil, normally unstable in storage, was extracted with 40 percent sodium hydroxide solution, yielding a very much more stable fuel. Portions of the extracted fuel were treated with sulfonic acids and stored at 43 C. Addition of the acids at levels as low as 10 ppm restores the instability of the extracted fuel and insoluble sediments are produced. The sediments were analyzed, using thin-layer chromatography, and infrared and mass spectroscopy, and compared with sediment generated by the raw untreated fuel with no additions. The sediments generated by the addition of sulfonic acids are similar to those produced by the untreated fuel. Minor differences are related to the two different sulfonic acids employed, providing evidence for incorporation of the sulfonic acids into the sediments. A fuel containing hydrotreated catalytically cracked gas oil, which did not produce sediment during 2 years of ambient storage, yields sediment very rapidly when treated with sulfonic acid. The sediment produced by this fuel is similar in nature to that produced by the raw catalytically cracked fuel.