What does DEF mean for diesel vehicles?

1 Answers
SanCarter
07/30/25 7:07am
DEF in diesel vehicles stands for Diesel Exhaust Fluid. Here is a related introduction to diesel exhaust fluid: 1. Function: It is used in diesel engines. It is a liquid used in SCR (Selective Catalytic Reduction) technology to reduce nitrogen oxide pollution in diesel vehicle exhaust. 2. Operation process: When nitrogen oxides are detected in the exhaust pipe, the urea tank automatically sprays diesel exhaust fluid. The diesel exhaust fluid and nitrogen oxides undergo a redox reaction in the SCR catalytic reaction tank, producing non-polluting nitrogen and water vapor, which are then discharged.
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