This standard specifies the Potentiometric titration, poten-tiometry method for the determination of the bromine index of aromatic hydrocarbons. It is suitable for aromatic hydrocarbons containing trace olefins at a final distillation point below 288 ° C and does not contain components lighter than isoJ alkane. The measurement range of the bromine index is 0mgBr/100g to 500mgBr/100g. The standard refers to a series of documents, including the preparation of standard titration solutions for chemical reagents and the general safety rules for sampling chemical products. In the term, the bromine index is defined as the number of milligrams of bromine consumed per 100 grams of sample when titrated with potassium bromide-potassium bromate standard solution under specified conditions.