Maplewood Imports

What is it?

Breakthrough BlueTEC technology controls emissions by driving exhaust gases through filters in the catalytic converter, where they mix with a new water-based additive called AdBlue®.  This process converts polluting nitrogen oxides into harmless nitrogen and water.  The result is a significant reduction in soot and pollutants, making the BlueTEC engine smoother, more efficient, quieter-yet also more robust-than its predecessors.  So regardless of which of the four luxurious models:

• The E350BlueTec
• The ML350 BlueTEC
• The GL350 BlueTEC
• The R350 BlueTEC

How Green is it?

Mercedes-Benz BlueTEC engines get 20 to 30% better fuel efficiency than similar-sized gas-powered cars, and can take you 600 miles-that's a trip from New York to Detroit-on a single tank of fuel.  But it's more than a break for the pocketbook.  BlueTEC vehicles now meet the emissions standards of all 50 states, including the 10 states with the most stringent pollution laws.

How is it made possible?

Mercedes-Benz credits the innovation of Ultra-Low-Sulfur-Diesel (ULSD) with making the BlueTEC system possible.  ULSD is a refined diesel fuel that has a much lower sulfur content compared to regular diesel fuel, resulting in dramatic diesel emission reductions.  ULSD is required for the precise engine and advanced exhaust treatment technology of all Mercedes-Benz diesel vehicles.

How BlueTEC works?

It starts with a high-pressure common-rail turbo direct injection diesel engine. "Common rail" refers to the method for injecting precisely the right amount of fuel directly into each cylinder at exactly the right moment. The turbocharger boosts horsepower, and the system recirculates the exhaust gas that powers it in order to consume any unburned fuel.

When exhaust gas leaves the engine, a multi-phase treatment process begins. By their nature, diesels tend to produce high levels of carbon monoxide, oxides of nitrogen known collectively as NO2, and particulate matter, also known as soot. Oxidation catalysts minimize the carbon monoxide and further reduce unburned hydrocarbons. A maintenance-free particulate filter, or soot trap, then reduces soot to nearly undetectable levels.

NO2 emissions are the trickiest to deal with. NO2 forms in the first place as a result of burning atmospheric air, and every lean-burning engine generates NO2 as the ratio of fuel to air in the combustion cycle decreases. Current approaches to trapping or destroying NO2 emissions all use catalysts that are vulnerable to degradation in the presence of sulfur. That's why it was necessary to put the whole country on a diet of ultra-low-sulfur fuel.

Mercedes-Benz has adopted a urea-injection system called AdBlue. That's because the NO2 trap technology used in cars would require too-frequent purging and thus reduce fuel economy.

The AdBlue system uses the SRC catalyst and a tank of liquid urea, which is misted into the exhaust stream. When the urea comes in contact with the hot exhaust gas, it releases ammonia, which in turn reacts with NO2 and emerges as harmless nitrogen and water. The urea supply is good for 10,000 miles, so it only needs to be refilled at the vehicle's normal service intervals. AdBlue system reduces NO2 emissions by 80 percent.