Pa high-quality environmentally friendly vehicles with urea (green car with urea water) heavy-duty trucks and buses and is a major contributor to global warming and air pollution. To deal with these two questions, Taiwan and the European Union has been initially implemented five / six environmental regulations (EURO 5/6), which for the car manufacturer is a great challenge. European heavy commercial vehicle sector, including DAF, Mercedes Benz, IVECO, Renault, Volvo, etc. In order to ensure compliance with the new EU environmental regulations EURO 5 and EURO 6 emission standard six of five phases, are chosen SCR Selective catalytic converter (Selective catalyst reduction), this system has to reduce nitrogen oxides and particulate emissions, and reduce the fuel consumption of the two kinds of important features. SCR converter is some of the most important AdBlue? / DEF catalyst reductant (AdBlue), which is approximately 32.5% of the use of urea and water formed, when it has not entered into before the catalytic converter is hot exhaust converted into ammonia, and ammonia nitrogen oxide catalytic converter with the onset of a chemical reaction within converted into nitrogen and water, reduce emissions of nitrogen oxides and particulates, but also on global warming get together will certainly inhibit effect. At that time, the Chinese heavy-duty diesel vehicles meet the national IV emission standard multi-use SCR emission control technology. SCR converter, some of the most important is the automotive urea solution, when it is not entered before the SCR converter have been transformed into the hot ammonia gas, ammonia and NOx with a catalytic converter within the onset of the chemical The reaction, is converted to nitrogen and water, to reduce the emission of nitrogen oxides and particulates. Car urea solution are bright, transparent colorless, odorless, non-toxic liquid for selective catalytic NOx reductant. Can effectively reduce emissions of NOx and particulates tail car, reducing fuel consumption. IV emission standards to meet the needs of the country, the choice of SCR emission control technology vehicles must add urea solution as catalytic reducing agent, to ensure vehicle emissions compliance.