UOP 614-16

This method is for the determination of either heptane or toluene insoluble material in petroleum oils and is applicable to samples that are fluid at about 80 degrees C. This method covers the range of 0.01 to about 25 mass-% insolubles. Solid particulate materials interfere. More viscous or solid materials such as asphalts may be analyzed using this method but will require using a heated sonicating bath (up to 60 degrees C). The data provided by this method may be used as an index to coking tendency of petroleum oils when considering their suitability as charge stocks to cracking or other processes.