D4377_10

Add the fresh sample solvent to the titration vessel and bring the solvent to endpoint conditions as described in 9.2 of the written standard. Add the crude to the titration vessel immediately after the mixing step described in 8.1.2.1 of the written standard using one of the following methods. Starting with a clean, dry syringe-- 10 or 5 milliliters, rinse the syringe two times with the sample and discharge to waste. Withdraw the required amount of sample. And discharge any air bubbles. Weigh the syringe to the nearest 0.1 milligrams. Inject the sample into the titration vessel. Clean the needle with a paper tissue, and reweigh the syringe. Titrate the sample until a steady endpoint for at least 30 seconds is reached. And record the volume of Karl Fischer reagent to the nearest 0.01 milliliters. See note 2 and note 4 of the written standard. The solvent should be changed when the sample content exceeds 2 grams of crude per 15 milliliters of solvent, or when 4 milliliters of titrant per 15 milliliters of solvent has been added to the titration vessel. For viscous crudes, add the sample to a clean, dry dropper bottle and weigh the bottle and crude. Quickly transfer the required amount of sample to the titration vessel with the dropper. Reweigh the bottle. Titrate the sample as in 10.2.1 of the written standard. After adding the sample, do not shake the cell.