Selective Catalytic Reduction (SCR) technology, now standard in diesel vehicles, has roots stretching back to the 1970s when engineers first used it in stationary power plants. The breakthrough came when researchers discovered that urea—the same organic compound found naturally in mammalian urine—could be transformed into ammonia to neutralize harmful nitrogen oxides. What makes this chemistry elegant is its simplicity: when heated, urea breaks down into ammonia, which then reacts with NOx in the catalyst to produce harmless nitrogen and water vapor.
For decades, this technology remained confined to industrial applications due to size and complexity constraints. It wasn't until the early 2000s, facing increasingly strict Euro emission standards, that automotive engineers successfully miniaturized SCR systems for trucks and passenger vehicles. The challenge was creating a stable, standardized urea solution that wouldn't freeze or degrade.
Today, AdBlue serves as the industry-standard 32.5% urea solution that makes this proven technology work in modern diesel engines.
