Chemical ionization mass spectrometric measurements of SO₂ emissions from jet engines in flight and test chamber operations

Abstract

Abstract. We report the results of two measurements of the concentrations and emission indices of gas-phase sulfur dioxide (EI(SO,-)) in the exhaust of an F100-200E turbofan engine. The broad goals of both experiments were to obtain exhaust sulfur speciation and aerosol properties as a function of fuel sulfur content. In the first campaign, an In all experiments the measured EI(SO2) was consistent with essentially all of the fuel sulfur appearing as gas-phase SO2 in the exhaust. However, accurate determination of S(IV) to S(VI) conversion was hampered by inconsistencies in the assays of total fuel sulfur content. IntroductionSulfur in the fuels burned by jet aircraft is the source of several gas-phase and aerosol species emitted in engine exhaust plumes, including SO2, SO3, H2SO 4, sulfate aerosols, and activated soot particles. These species contribute to the impact of the civil and military air fleets on upper troposphere/ lower-stratosphere chemistry, aerosol loading, contrail and cloud formation, radiation balance, and ozone concentration

Effect of relative humidity on the detection of sulfur dioxide and sulfuric acid using a chemical ionization mass spectrometer

“…In this section, we present only a brief description of the instrument, because it is similar to that previously described in the literature [12,24,26]. Fig.…”

“…These include: gas chromatography with flame photometric detection (FPD) (detection limit (DL) = 0.1-0.3 ppb); ultraviolet fluorescence (DL < 0.3 ppt); [10] differential optical absorption spectrometry (DOAS) (DL = 10-100 ppt), tunable diode laser spectroscopy (TDLS) (DL = 0.5 ppb), and Fourier-transform infrared spectrometry (FTIR) (DL = 25 ppb, falling to 0.01 ppb with sample concentration using Matrix Isolation) [11]. Chemical ionization mass spectrometry (CIMS) has also been used to measure SO 2 in the troposphere (DL = 1 ppb [12] and 0.5 ppt [13][14][15][16]). The only in-situ atmospheric measurements of sulfuric acid have been carried out using CIMS.…”

“…The instrument has been used to measure a variety of atmospheric species, including ambient SO 2 [12,24,25]. Here, we used a new version of the spectrometer designed and developed by AFRL, and built by Aerodyne Research, Inc. (ARI).…”

Atmospheric measurements of gas-phase HNO&lt;sub&gt;3&lt;/sub&gt; and SO&lt;sub&gt;2&lt;/sub&gt; using chemical ionization mass spectrometry during the MINATROC field campaign 2000 on Monte Cimone

“…The intercomparison, however, showed, that there are no validated standards for low pptv concentrations. CIMS has proven to be a versatile and extremely sensitive technique also for monitoring SO 2 , in particular with regard to aircraft-borne measurements due to its sensitivity to mixing ratios less than 100 pptv and response times faster than 15 s. (Arnold et al, 1997;Hunton et al, 2000;Reiner et al, 2001). …”

Airborne mass spectrometers: four decades of atmospheric and space research at the Air Force Research Laboratory

“…Figure 12 shows mass spectra taken during the SNIF-3 (SASS Near Field Interaction Flight experiment) flight in June, 1997, while measuring airplane engine exhaust. 104 Four spectra are shown in two panels. The bottom panel shows a spectrum taken during a calibration as bold and a reference spectrum as a thin line.…”