Abstract: Based on the renewal of items relating to sulfur and corrosion in motor gasoline quality standards, combined with sulfur distribution, processing and blending techniques of gasoline, the reason and the development direction of the test method changes for sulfur content in automobile gasoline and the relationship between sulfur content and mercaptan sulfur content were analyzed. Influence of the structure of -SH in mercaptan molecule and chemical environment such as composition, additives and other factors, on regularity of the detection limit in doctoral test was also discussed. It is pointed out that the chemical activity variances of -SH among different structures of mercaptan is the reason why doctor's test and copper sheet corrosion test are not unified and that the actual copper corrosion test can integrally and objectively reflect the corrosion performance of the sample gasoline. The effective control of sulfur content and copper corrosion can both reduce the emission of SOx and weaken corrosion extent.

Key words: quality standard, sulfur content, mercaptan sulfur content, doctoral test, copper corrosion