ASH IN PETROLEUM COKE: D4422
EXPLANATION
The ash content is one of the properties used to evaluate petroleum coke and indicates the amount of undesirable residue present. Acceptable ash content varies with the intended use.
Preparation and testing of the analysis sample must neither remove nor add ash. Improper dividing, sieving, and crushing equipment, and some muffle furnace lining material can contaminate the sample. High sulfur content of the furnace gases, regardless of the source of the sulfur, can react with an alkaline ash to produce erratic results. The furnace must be swept with air to achieve oxidation and to decrease the sulfur content of the gases.
TEST SUMMARY
A sample of petroleum coke is dried, ground, and ashed in a muffle furnace at 700 to 775 ° C.
TEST PRECISION
Repeatability: 0.02
Reproducibility: 0.06
Bias depends on the conformance to the empirical conditions of the test. The ash content must not be understood to be the same as the mineral content of the petroleum coke.
