Abstract
The objective of this study was to identify the influence of sampling and analytical approach on the quality of NH3 emission data of a gasoline-fuelled three-way catalyst vehicle. NH3 concentration measurements have been performed in the tailpipe and in the diluted exhaust after a constant volume sampling (CVS) system during five different test cycles. Chemical ionisation mass spectrometry (CI-MS) and Fourier transform infrared spectroscopy (FTIR) were used to acquire ammonia concentrations in real-time. Independently, NH3 emission rates were determined by continuous absorption of a flow-proportional sample of exhaust gas in diluted sulphuric acid and subsequent ion chromatography (IC). Ammonia emission rates ranged from 22–94 mg km-1. The results of the three compared techniques are in good agreement. Furthermore, time-resolved ammonia emission profiles recorded by CI-MS and FTIR coincided with respect to emission levels as well as emission dynamics. However, in the dilution tunnel, severe ammonia adsorption was observed leading to long lasting memory effects or even analyte loss. Therefore, neither ammonia real-time emission data nor NH3 emission rates should be acquired after a CVS system.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: International Journal of Environment and Pollution
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
