Ultra-Low Sulfur in Automotive Fuels
Application Notebook
Globally, the permitted sulfur limit in fuel oils has been decreased to 10 ppm in many countries and regions.
Globally, the permitted sulfur limit in fuel oils has been decreased to 10 ppm in many countries and regions. For compliance verification, X-ray fluorescence (XRF) spectrometry is the definitive analysis tool for use at distribution terminal and refineries, as well as mobile or stationary testing laboratories
Rigaku Micro-Z ULS is a benchtop wavelength dispersive X-ray fluorescence (WDXRF) spectrometer with fixed optics optimized for sulfur analysis. The atmosphere in the optics path of the Micro-Z ULS is a vacuum so that helium gas is not required. The spectrometer is designed to minimize the restrictions in installation such as cooling water, special power supply, installation space, etc.
Experimental Conditions
Micro-Z ULS is equipped with an air-cooled 40 W Cr-target X-ray tube and a doubly curved RX-9 analyzing crystal optimized for low concentration sulfur. The counting time was 300 s for peak and background measurements. 4.0 mL of each diesel fuel sample was poured into a liquid XRF cup (inner diameter 35 mm) equipped with 2.5 μm Mylar® film.
Figure 1: Calibration results for diesel fuel.
Results
Repeatability tests were carried out using a representative sample. For each, two aliquots were prepared and analyzed using the calibration shown in Figure 1; this process was repeated 20 times. The test results are tabulated in Table I for diesel fuel, in which the average and the difference of two aliquots are shown respectively. Lower-limit-of detection (LLD) was calculated as 0.3 ppm sulfur.
Table I: Repeatibility results for diesel fuel
Conclusion
Low concentration sulfur in petroleum-based fuel can be routinely analyzed with high accuracy and precision with the Micro-Z ULS, a benchtop WDXRF spectrometer with fixed optics, which does not require He gas, external water supply or special power supply. This application note demonstrates that the performance of the Micro-Z ULS meets the requirements of ASTM D2622-10.
Rigaku Corporation
9009 New Trails Drive, The Woodlands, TX 77381
tel. (281) 362-2300, fax 281-364-3628
Website: www.Rigaku.com
How Do We Improve Elemental Impurity Analysis in Pharmaceutical Quality Control?
May 16th 2025In this final part of our conversation with Harrington and Seibert, they discuss the main challenges that they encountered in their study and how we can improve elemental impurity analysis in pharmaceutical quality control.
How do Pharmaceutical Laboratories Approach Elemental Impurity Analysis?
May 14th 2025Spectroscopy sat down with James Harrington of Research Triangle Institute (RTI International) in Research Triangle Park, North Carolina, who was the lead author of this study, as well as coauthor Donna Seibert of Kalamazoo, Michigan. In Part I of our conversation with Harrington and Seibert, they discuss the impact of ICH Q3D and United States Pharmacopeia (USP) <232>/<233> guidelines on elemental impurity analysis and how they designed their study.
LIBS Illuminates the Hidden Health Risks of Indoor Welding and Soldering
April 23rd 2025A new dual-spectroscopy approach reveals real-time pollution threats in indoor workspaces. Chinese researchers have pioneered the use of laser-induced breakdown spectroscopy (LIBS) and aerosol mass spectrometry to uncover and monitor harmful heavy metal and dust emissions from soldering and welding in real-time. These complementary tools offer a fast, accurate means to evaluate air quality threats in industrial and indoor environments—where people spend most of their time.
