ASTM D7501-09b

Some substances that are soluble or appear to be soluble in biodiesel (B100) at room temperature will, upon cooling to temperatures above the cloud point or standing at room temperature for extended periods, come out of solution. This phenomenon has been observed in both B100 and BXX blends. These substances can cause filter plugging. This method provides an accelerated means of assessing the presence of these substances in B100 and their propensity to plug filters.

B100 biodiesel fuels that give short filtration times are expected to give satisfactory operation of BXX blends at least down to the cloud point of the biodiesel blends.

The test method can be used in specifications as a means of controlling levels of minor filter plugging components in biodiesel and biodiesel blends.

1.1 This test method covers the determination by filtration time after cold soak of the suitability for a biodiesel (B100) blend stock that meets all other requirements of Specification D6751 and has a cloud point below 68°F (20°C) to provide adequate low temperature operability performance to at least the cloud point of the finished blend.

1.2 The formal precision of this test method is included in 13.1 on Precision.

1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.