Diesel SUV fans can rejoice: Mercedes-Benz has become the world's first car producer to receive a certificate for licensing BlueTEC SUVs in all 50 US states. It's been true (seemingly forever) that diesels would only be sold in 45 (or even 42) states. But as we reported the other day, the Stuttgart-based manufacturer will soon launch three BlueTEC SUVs—the ML 320 BlueTEC, the R 320 BlueTEC and the GL 320 BlueTEC—which feature clean diesel technology that meets American Bin 5 and ULEV emission standards. Now the company can make the claim officially, and finally put to rest the big question mark over whether or not clean diesels will ever pass certification.

Here's the rundown so far, as explained by Mercedes: "Components [normally used in diesel cars] include an oxidizing catalytic converter and a particulate filter. The primary objective, however, is to reduce nitrogen-oxide emissions drastically, since these are now the only exhaust-gas constituents that are more prevalent in diesel engines than they are in their petrol [gasoline] counterparts.

"Mercedes-Benz has developed two versions for this. Both the E 320 BlueTEC Saloon available in the US and the E 300 BlueTEC variant for the European market are equipped with a combination of oxidizing catalytic converter and particulate filter with an NOx storage catalytic converter and an additional SCR catalytic converter (SCR= Selective Catalytic Reduction). The second BlueTEC version is being used for the new GL 320 BlueTEC, ML 320 BlueTEC and R 320 BlueTEC models, in which AdBlue, a harmless aqueous urea solution, is injected into the exhaust-gas stream. This process releases ammonia, which converts up to 80 percent of the nitrogen oxides into harmless nitrogen and water by a process of reduction in the downstream SCR catalytic converter." This latter system is enabling 50-state certification here in the U.S.

Source: Daimler Global Media