WATER IN CRUDE OIL BY DISTILLATION: D4006
(Equivalent Test Method: IP 358)
TEST SUMMARY
The sample is heated under reflux conditions with a water immiscible solvent (xylene), which co-distills with the water in the sample. Condensed solvent and water are continuously separated in a trap; the water settles in the graduated section of the trap, and the solvent returns to the distillation flask.

TEST PRECISION