ASTM D2274 for oxidation stability of distillate fuel oil (Accelerated method)
9. Samples and Sampling
9.1 When obtaining samples for the laboratory, follow Practices D4057 or D4177, or other standard practice capable of providing representative samples.
9.2 Analyze fuel samples as soon as possible after receipt. When a fuel cannot be tested within one day, blanket it with an inert gas such as oxygen-free nitrogen, argon, or helium and store at a temperature no higher than 10°C (50°F) but not lower than the cloud point. (Warning - Plastic containers are not acceptable for samples due to the potential for leaching of plasticizers. Samples should be taken preferably in metal cans previously cleaned according to Practice D4057. Borosilicate glass containers can be used if they are wrapped or boxed to exclude light. Do not use soft (soda) glass containers.)
9.3 Test Samples - Reduction of the laboratory sample to test sample size (about 400 mL for each determination) depends upon the size of sample received by the laboratory. If the laboratory sample is stored in a tank, drum, or 19-L (5-gal) or larger can, use the pertinent procedures of Practice D4057. Thoroughly mix smaller laboratory samples by shaking, rolling, or other techniques before taking an aliquot portion by pouring, pipetting, or other means. Clean any tube, thief, pipet, beaker, or other substance that is to contact the laboratory sample with trisolvent and rinse with a portion of the sample prior to use. Prior to mixing thoroughly and taking an aliquot, allow samples that have been stored at temperatures much below 10°C (50°F) to warm to room temperature; thus allowing any separated wax to redissolve and to allow the viscosity to decrease to a point where mixing is effective.
10. Preparation of Apparatus
10.1 Preparation of Glassware Other Than Oxidation Cells - Rinse all glassware thoroughly with trisolvent followed by water, then wash with a mildly alkaline or neutral laboratory detergent. Rinse three times with deionized or distilled water followed by acetone to remove water.
10.2 Preparation of Oxidation Cells and Accessories - After completion of 10.1, fill oxidation cells with laboratory detergent in water. Place the oxygen delivery tube in the oxidation cell, place the condenser over the oxygen delivery tube and allow to soak at least two hours. Wash, drain, then rinse five times with tap water followed by three rinses with distilled or deionized water meeting Specification D1193 Type III requirements. Rinse with acetone; drain and allow the oxidation cell and oxygen delivery tube to dry.
10.3 Preparation of Evaporating Beakers - Dry the 200-mL cleaned beakers (10.1) for 1 h in an oven at 105° more or less 5°C (221 more or less 9°F). Place the beakers in a desiccator (without desiccant) and allow to cool for 1 h. Weigh beakers to the nearest 0.1 mg.
