Improved catalytic converters for selective catalytic reduction

为了满足严格的政府规定的汽车排放目标和改进的燃料经济性，人们对使用稀燃发动机（柴油、汽油或天然气）非常感兴趣。在这种环境下，排放物的控制，特别是氮氧化物的控制，是具有挑战性的，通常使用选择性催化还原（SCR）来实现。在该反应中，氨被注入废气中，然后与NOx催化反应以产生氮气。已经使用了几种催化剂，但是它们在水的存在下过度失活。正在开发的最新催化剂是基于铜菱沸石。由于其相对较新，没有太多的信息，使计算机模拟的反应堆，这是一个越来越重要的工具，用于开发新的转换器。

To meet strict government mandated automotive emission targets and improved fuel economy, there is great interest in the use of lean burn engines, either Diesel, gasoline or natural gas. Control of emissions, especially oxides of nitrogen, is challenging in this environment, and is usually achieved using selective catalytic reduction (SCR). In this reaction, ammonia is injected into the exhaust, which then catalytically reacts with NOX to produce nitrogen. Several catalysts have been used, but they suffer from excessive deactivation in the presence of water. The newest catalyst being exploited is based on copper chabazite. Because of their relative newness, there is not much information available that allows for the computer modelling of the reactor, which is an increasingly important tool used in the development of new converters.