Diesel exhaust fluid

A small bottle and a large cannister, both labeled as "AdBlue"
A 1.5-liter and a 10-liter AdBlue container
Hino truck and its SCR next to the diesel particulate filter (DPF) with regeneration process by the late fuel injection to control exhaust temperature to burn off soot[1][2]
Passenger car using an AdBlue pump

Diesel exhaust fluid (DEF; also known as AUS 32 and marketed as AdBlue[3]) is a liquid used to reduce the amount of air pollution created by a diesel engine. Specifically, DEF is an aqueous urea solution made with 32.5% urea and 67.5% deionized water. DEF is consumed in a selective catalytic reduction (SCR) that lowers the concentration of nitrogen oxides (NO
x) in the diesel exhaust emissions from a diesel engine.[4]

  1. ^ "Hino Standardized SCR Unit". Hino Motors. Archived from the original on 5 August 2014. Retrieved 30 July 2014.
  2. ^ "The DPR Future" (PDF). Hino Motors. Retrieved 30 July 2014.
  3. ^ "What is the function of AdBlue?". Eurol lubricants. 18 May 2020. Retrieved 16 November 2021.
  4. ^ "What is DEF?" (PDF). Cummins Filtration. Archived from the original (PDF) on 23 March 2021.