Petroleum Testing Services

Phosphorus Content in Biodiesel by ASTM D4951

Method reference ASTM D4951 is used to determine the concentration of Phosphorus (P) in biodiesel. ASTM D4951 is approved for use in the ASTM specification for biodiesel (B100), ASTM D6751.

The presence of phosphorus in B100 can poison the catalytic converter on a vehicle, reducing its ability to treat exhaust. Phosphorus may also create hard deposits on piston crowns, valves, and injectors, affecting engine performance and reliability. As such, ASTM D6751 requires a maximum of 10ppm (m/m) phosphorus in B100.

Procedures included on our A2LA Scope of Accredidation to ISO/IEC 17025:2005 are designated as such.


Test Method Reference Min. Sample Vol. Price ISO 17025
Phosphorus Content ASTM D4951 20 g $75.00