Diesel Exhaust Fluid (DEF)

Sellers Petroleum proudly markets Airgas DEF


In support of EPA 2010 emissions standards, oxides of nitrogen and particulate matter (PM) are reduced by 90% from 2004 standards to near-zero emissions levels. In order to meet these new standards and the needs of customers, engine manufacturers have invested in new and innovative technologies. The leading technology being used to achieve the emissions goals is SCR (Selective Catalytic Reduction). This proven aftertreatment technology enables the engine to be fully optimized for performance and fuel economy.​​

​How Selective Catalytic Reduction Technology Works

SCR technology is designed to permit nitrogen oxide (NOx) reduction reactions to take place in an oxidizing atmosphere. It is called "selective" because it reduces levels of NOx using ammonia as a reductant within a catalyst system. The reducing agent reacts with NOx to convert the pollutants into nitrogen, water and tiny amounts of carbon dioxide (CO2) - natural elements common to the air we breathe everyday. The reductant source is usually automotive-grade urea, otherwise known as Diesel Exhaust Fluid, which can be rapidly hydrolyzed to produce the oxidizing ammonia in the exhaust stream. SCR technology alone can achieve NOx reductions in excess of 90%.​

DEF Packaging

Sellers Petroleum maintains a large inventory of DEF products.  The DEF products are available in 250 Gallon totes, 55 gallon drums and 21/2 Gallon jugs.  We can also provide bulk deliveries of 500 gallons or more.

What is Diesel Exhaust Fluid (DEF)?

DEF is 32.5% solution of high-purity urea in water that is used with the Selective Catalytic Reduction system (SCR) to reduce emissions of nitrogen oxides (NOx).  It is a non-fuel nor is it a fuel additive.  It should only be used in a DEF dedicated tank. 

How much DEF do I need?

The average consumption of DEF is generally 3% per gallon of diesel fuel.  Click on the consumption calculator to find out how much DEF product you will need based on yearly mileage per Diesel Vehicle that require DEF.

How do I store DEF?

DEF can be stored in temperatures between 10 and 90 degrees Fahrenheit.  In warm temperature regions it is recommended to store DEF in shaded areas. In cold temperature regions it is recommended to store DEF in a storage unit.

Is DEF harmful?

DEF is a non hazardous liquid and is classified under the minimum risk category of transportable fluids.  See the Material Data Safety Sheet for detailed information.