In the eyes of many, we are in the middle of a revolution as we see the emergence of a new industry built around the production of biofuels as an alternative energy source. Biofuel production is seen as a way to reduce the reliance on the diminishing supply of oil resources while also helping economic development and job creation in rural areas. Opinions differ on the environmental impact of biofuels. Some see it as cleaner and less environmentally degrading than fossil fuels, helping slow and possibly reverse global warming. Others warn that there may be climate-change and food supply consequences as farmers rotate and expand their crop growth to supply the growing industry.

Regardless, world governments are forging ahead with mandates that biofuel be a component of the fuel mix.

In the United States, the total amount of biofuels added to gasoline is required to increase to 36 billion gallons by 2022, from 4.7 billion gallons in 2007. The EU has mandated that countries use 5.75 percent biofuel for transportation by the end of 2008.

In Canada, legislation is imminent to require that gasoline contain 5% renewable content by 2010 and that diesel have 2% by 2012. Similar mandates are in place worldwide.

ASTM Methods & Phase Technology

ASTM International standard D6751 details quality specifications that pure biodiesel (B100) must meet before being blended with petroleum diesel fuels. D6751 is generally comparable to the European standard EN 14214.

ASTM D6751 includes ASTM D7397, ASTM D5773, and ASTM 2500 (manual method) as the only allowed techniques for cloud point testing of biodiesel. ASTM D7397 and D5773 are used in Phase Technology's CPA-T30 and 70X series analyzers.

ASTM D6751 also specifies that biofuels meet D445 Test Method for Kinematic Viscosity. Phase Technology’s VA-300 viscosity analyzer conforms to this standard.

Generally, B100 is not used to power motor vehicles; it is blended with other fuels. ASTM D6751 is critically important for biodiesel producers and blenders, but less of a consideration for downstream operations. In most countries (like the U.S.) with government biodiesel mandates and subsidized tax credits, B100 is required to meet and comply with ASTM D6751.

ASTM D7467 is the specification that applies to biodiesel/diesel blends of between six (B6) and twenty (B20) percent. These grades are suitable for various types of motorized diesel engines. ASTM D5773 and D7397 (as used in Phase Technology 70X and CPA-T30 analyzers) are included as methods for determining cloud point in ASTM D7467. Additionally, ASTM D7467 specifies that the biodiesel component must meet the requirements of ASTM D6751.

Testing Biofuels

Biofuels can have very different characteristics when compared to petroleum products. The cloud point for biodiesel blends is higher than it is for conventional diesel fuel, so it has a higher risk of congealing and forming wax crystals at cold temperatures. This makes cloud point a critical test for biodiesel producers. Tight quality control in accordance with ASTM standards is crucial.

Biodiesel blends generally have higher viscosity levels than petroleum products. This can result in operational problems, engine deposits, and poor combustion. Biodiesel producers adjust their blends to lower the viscosity. Finding the perfect “sweet spot” requires an accurate, precise kinematic viscosity test result.

Phase Technology cloud point and viscosity analyzers deliver test results that meet or exceed all biofuels standards. In an industry in which quality and credibility go hand-in-hand to create market acceptance and profit, you can rely on us as your partner in precision.


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