Page 27 - Shimadzu Journal vol.8 Issue2

Hydrocarbon Processing Industry

Discussion the new IMO requirements of <0.50% (m/m). Even when operat-
ing the instrument without the use of the helium-purged chamber,
Calibration of the EDX-7000 with known standards yielded a sensitivity was only diminished slightly, to 5.61 ppm. Again, this
linear and steep calibration curve, critical to effective quantification value is well within the scope of new IMO regulations.
(e.g., Figs. 5 and 6). Such a predictable response on the instrument
results in accurate and precise quantification of unknown samples. The marine fuel sample tested contained 2.96% sulfur, which was
not unexpected due to its age predating the new IMO 2020 reg-
ulations. A fuel such as this could still be used in seagoing vessels
provided that they have appropriate scrubbers in their exhaust
Repeatability results per ASTM D4294 for base oil show that the stacks to minimize SOx emissions. Nonetheless, this demonstrates
EDX-7000 can comply with the method at sulfur concentrations of appropriate quantification abilities for the EDX-7000 and EDXRF,
≥500 ppm using a non-purged analytical chamber and ≥50 ppm in general, for sulfur in heavy fuels.
when purging the chamber with helium (e.g., Fig. 7). Furthermore,
for sulfur concentrations of ≥500 ppm, the analytical time can be
reduced by 50%, more stringent than the scope of the method,
and still comply with repeatability requirements. For diesel fuel, Conclusions
repeatability complied with ASTM D4294 at sulfur concentrations
of ≥100 ppm. Regulations on the chemistry of fuels continue to become more
stringent in efforts to minimize their environmental impact. The
reduction of sulfur content in fuels minimizes SOx emissions,
thereby decreasing their potential to generate acid rain, smog, and
negatively affect human health. Strict regulations on the sulfur con-
tent of on-highway fuels, such as gasoline and diesel, have been in
place for years, whereas those for fuel oils and marine fuels have
existed but have historically allowed for higher total sulfur content.
New regulations from the IMO enacted in 2020 limit the sulfur
content of marine fuel oil to 0.50% (m/m) or to equip ships with
emission-reducing scrubbers.

Due to these new regulations, refiners that produce fuel oil for
marine use must expand analytical testing for compliance purposes.
Analysis of fuels by EDXRF instruments has gained traction due
Figure 7. Repeatability of 500 ppm sulfur sample
using helium-purged sample chamber. to their ease of use, minimal requirements in terms of laboratory
infrastructure, and their sensitivity appropriate for sulfur at new
regulatory limits. Shimadzu’s EDX-7000 provides a simple way for
Reproducibility results per ASTM D4294 for base oil show that the analysis of sulfur, and other elements, in petroleum products. This
EDX-7000 can comply with the method at sulfur concentrations of methodology allows for fast analysis with limited sample prepa-
≥500 ppm using both a non-purged and a helium purged chamber. ration and a minimum of conventional laboratory infrastructure.
For diesel fuel, the concentration range is lower at ≥100 ppm sulfur
using a helium purge. The method and data outlined above demonstrate the applicability
of Shimadzu’s EDX-7000 towards ASTM D4294 and ISO 8754 for
For both repeatability and reproducibility as per ISO 8754, the measuring total sulfur in petroleum products in addition to compli-
EDX-7000 complied across the entire concentration range of 0.03 ance with the 2020 IMO standards. Furthermore, successful anal-
to 4 weight percent sulfur using ambient (non-purged) conditions. ysis of a pre-regulation fuel demonstrates the applicability of the
EDX-7000 for such analyses.
Calculations of the LLD demonstrate sensitivity of the EDX-7000
for sulfur as low as 2.49 ppm. This concentration is far lower than

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