USA: Fuels: Biodiesel Fuel

ASTM Standards

The first national biodiesel specification in the USA was the ASTM standard D6751, Standard Specification for Biodiesel Fuel (B100) Blend Stock for Distillate Fuels, first adopted in 2002. The D6751 standard covers biodiesel (B100) used as a blending component with petroleum diesel fuels.

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ASTM D6751 [6181] defines six grades of B100 based on sulfur, low temperature properties and metal content: Grade No. 1-B S15, Grade No. 1-B S15 LM, Grade No. 1-B S500, Grade No. 2-B S15, Grade No. 2-B S15 LM and Grade No. 2-B S500. Low metal grades (LM) are intended for use in engines with SCR of DPF aftertreatment technologies. Requirements and test methods of the D6751 standard are discussed in detail under Biodiesel Fuel Standards.

No standards currently exist in the USA that would cover neat biodiesel (B100) for use as automotive fuels. In 2008, ASTM adopted two separate specifications: (1) for biodiesel blends of B5 or less and (2) for biodiesel blends from B6 to B20.

Blends of B5 or less were incorporated into the diesel fuel standard, ASTM D975. Up to 5% biodiesel can be blended into No. 1 or No. 2 diesel fuel so long as:

• the biodiesel component meets the requirements of ASTM D6751 and
• the final blend meets the requirements of D975.

Labeling of the of the finished blend is not required so that it may not be possible for the purchaser to know whether or not the fuel contains biodiesel unless an analysis is carried out.

Requirements for blends from B6 to B20 are covered by the ASTM D7467 specification [6182]. Three grades are defined depending on the sulfur content: Grade B6 to B20 S15 (15 ppm sulfur max.), Grade B6 to B20 S500 (500 ppm sulfur max.) and Grade B6 to B20 S5000, (5000 ppm sulfur max.). For grade B6-B20 S15, the biodiesel component shall be one of the S15 LM grades from D6751 unless the fuel is used in diesel engines without SCR or DPF aftertreatment technologies.

Other Requirements

Environmental Protection Agency

In 2007, the EPA issued a guidance document which clarified its regulatory requirements for biodiesel producers and blenders/users. While the Clean Air Act does not give EPA the authority to directly require biodiesel producers to adhere to ASTM D6751, it does provide EPA with the authority to regulate fuels and fuel additives in order to obtain information about their emissions and health effects and where appropriate, to reduce the risk to public health from exposure to their emissions. EPA exercises this authority by requiring producers and importers of fuels or additives to register their product with the EPA.

For biodiesel producers, the registration process requires the following information:

1. The feedstocks used to produce biodiesel.
2. A description of the manufacturing process used to produce biodiesel.
3. Emissions and health effects testing on the manufacturer’s biodiesel, or alternatively proof of registration with the National Biodiesel Board (NBB) showing access to the NBB’s Tier 1 and Tier 2 emissions and health effects testing data.
4. Test results from a representative sample of the manufacturer’s biodiesel demonstrating compliance with the parameters specified in ASTM D6751.

The EPA has stated that if a biodiesel producer’s product does not meet the requirements of D6751 that were in effect at the time a producer registered their product, the product will be considered to be an unregistered fuel and subject to a significant fine. While D6751 has had numerous changes since its introduction in 2002, and this approach may not hold all biodiesel producers to the same standard, it does allow EPA to indirectly require them to maintain a minimum level of product quality.

Internal Revenue Service

The IRS issued Notice 2009-34 stating that effective October 1, 2009, biodiesel will be ineligible for some tax credits unless it meets the requirements of the version of ASTM D6751 published October 13, 2008 (i.e., ASTM D6751-08). This is the version of D6751 that introduced the Cold Soak Filtration Test limits for B100.

US Military Specifications