One important aspect of catalysis research is the reduction of NOxin such applications as car exhausts and power plants. This research involves many challenges in meeting current emission legislation whilst keeping catalyst cost low. Several NOxreduction technologies have emerged in previous years, some of which have now been commercialised including selective catalytic reduction (SCR) with NH3, urea and hydrocarbons, and NOxstorage and reduction (NSR). NSR technology consists of two cyclic steps that occur on a lean NOxtrap (LNT) catalyst. The LNT catalyst readily stores NO2as compared to NO. For this reason, NO should be oxidised to NO2to achieve an acceptable level of NOxstorage. This application note describes the measurement of NO2using them/z46 peak and the NO/NO2ratio in a research application using the Hiden HPR-20. The data highlights the ability of the QIC series gas analysis systems to deconvolute and quantify low levels of NO in high concentrations of NO2.
