Compliance with mandatory fuel sulfur restrictions has always necessitated the use of sulfur test procedures. The test technique limits have been pushed farther as fuel sulfur standards have tightened, for example, to 15 mg/kg for ultra low sulfur diesel (ULSD) in North America. At high concentrations, quantifying fuel sulfur reliably and precisely is extremely difficult. Many test procedures are ineffective due to a lack of precision and/or accuracy.
Wet chemistry, X-ray fluorescence, atomic spectroscopy, and other thermal combustion procedures with diverse detection techniques such as microcoulometry, UV-fluorescence, and electrochemistry are all used to detect fuel sulfur.
Some of the more typical test methods for quantifying sulfur in middle distillate fuels are included in Table 1. The range of sulfur contents and ASTM D975 diesel fuel grades that they apply to are also shown.
How do you measure sulfur content?
X-ray fluorescence spectroscopy, non-dispersive infrared spectroscopy, and titration procedures can all be used to determine the average range (ppm) of sulfur. Sulfur determination using X-ray fluorescence techniques is generally employed in a broad testing range (ppm to percent) and is suitable to all petroleum samples.
How do you test sulphur content in oil?
Sulfur content is also measured according to ASTM D4294 (Standard Test Method for Sulfur in Petroleum Products by Energy-Dispersive X-Ray Fluorescence Spectroscopy). This method may be used to test both volatile and non-volatile petroleum products with sulfur contents ranging from 0.05 to 5% by mass.
Procedure for testing for sulfur
When handling lead acetate paper or hydrogen peroxide, put on disposable gloves; when heating the pipette or the samples, put on heat-resistant gloves; and put on eye protection. When utilizing any form of open flame, use caution and follow the manufacturer’s recommendations. If possible, conduct this test in a well-ventilated location or in a fume hood. Used lead acetate papers should be treated as hazardous waste and disposed of appropriately.
- Melt the tapering tip of a Pasteur pipette with a flame to seal it. (A butane torch is ideal, but an alcohol lamp will also suffice.)
- Using a scalpel or scissors, cut a sample of roughly 10 mg (0.01 g) from the material to be examined.
- Push the sample to the tapered part of the pipette with a wooden stick. Don’t cram it too tightly.
- If you’re using lead acetate test paper from a roll, cut a 5-cm-long piece. If the test paper is broader than the pipette, fold it in half lengthwise to allow it to be placed into the pipette.
- Using another pipette or an eyedropper, add a drop or two of water to the folded test paper. Water should be able to wick its way down the full length of the paper. Don’t overdo it with the water.
- Place the test paper towards the open end of the pipette with tweezers. The sample should not be touched by the test paper.
- Warm the sample gently above (but not directly in) a flame until it smokes and the fumes reach the test paper. Hold the tube horizontally or slightly tilted so the paper is lower than the sample since the fumes are denser than air (but do not tilt so much that the sample moves).
- Allow the reaction to occur by leaving the tube horizontal for several minutes.
- On the test paper, lightly spray or drop a drop of hydrogen peroxide (3 percent v/v).
- If the paper turns dark brown or black after being exposed to the fumes from the sample and then turns white after being exposed to hydrogen peroxide, the test is positive for sulfur.
- The test should be performed on a sample that contains sulfur and a sample that does not contain sulfur first, and subsequently on unknown samples.
What is the sulfur content of diesel fuel?
Diesel Standards Overview Beginning in 2006, the Environmental Protection Agency (EPA) began implementing more rigorous restrictions to reduce the amount of sulfur in diesel fuel to 15 parts per million (ppm).
How do you measure sulphur content in coal?
Monosulfide (S=), total sulfur
Sulfate sulfur (S2=) and pyritic sulfur (S2=)
The concentrations of (S04=) are determined in
Coal samples in their entirety. Total sulfur, monosulfide sulfur, and sulfate sulfur are all types of sulfur.
are defined by the SO2’s infrared absorption
generated by the combustion of entire coal or coal in its many forms
Sulfur in an oxygen-rich environment. Sulfur pyritic concentration
is measured indirectly by determining the amount of iron in a sample.
Flame atomic absorption spectrometry was used to separate the fractions. The
The concentration of organically bound sulfur is estimated using
subtracting the total of monosulfide and sulfate concentrations
The overall sulfur concentration is depleted of sulfur and pyritic sulfur. Coke
As control samples, coal standards are used to measure the
The analytical processes’ precision and accuracy. The
as defined by the precision of the approach for each form of sulfur
is roughly 5- to 10-fold higher than that of replicate conventional analyses.
The relative standard deviation is 10%. The limit of determination
roughly 50 m g (30% relative standard) for sulfur
deviation), which corresponds to 0.01 percent sulfur in 0.5 g.
a coal mine
After API gravity, the sulfur content of crude oils is the second most important attribute. Sulfur content in oil is measured in weight percent sulfur and normally ranges from 0.1 to 5.0 percent wt. ASTM D129, D1552, and D2622 are the standard methods for measuring sulfur content, depending on the sulfur level. Crude oils containing more than 0.5 percent sulfur by weight must be treated extensively during the refining process. Crude oils can be classed as sweet or sour based on their sulfur concentration (0.5 percent percent wt S). Higher-concentration sulfur species are separated into higher-boiling fractions and distillation residua during the distillation process. One of the most significant procedures in a refinery for producing fuels that comply with environmental laws is removing sulfur from petroleum products.
The nitrogen concentration of crude oils is frequently stated as a percentage of the total weight of the oil. In crude oil fractions, basic nitrogen molecules are especially undesirable because they deactivate the acidic sites on catalysts employed in conversion operations. Some nitrogen compounds can be corrosive as well. Nitrogen removal is required in refineries for crude oils with nitrogen concentrations greater than 0.25 percent by weight.
What is the effect of sulphur in fuel?
Sulfur is a naturally occurring component of crude oil that can be found in gasoline and diesel unless it is eliminated. Sulfur in gasoline reduces the efficiency of emission control devices and contributes to pollution in the atmosphere. Reduced sulfur content in gasoline allows for more effective emission controls and lowers pollution levels.
The Tier 2 Gasoline Sulfur program, which was completed in 2000, lowered the sulfur content of gasoline by up to 90%, allowing new emission control technology in vehicles and trucks to be used, resulting in less harmful air pollution. The Tier 2 program was the first time the Environmental Protection Agency (EPA) looked at automobiles and fuels as a whole. Beginning in 2004, the EPA was required by the Clean Air Act to investigate the need, practicality, and cost-effectiveness of tougher tailpipe emission regulations. Beginning in model year 2004, requirements for the use of low-sulfur gasoline allowed advanced emission control systems to be installed in automobiles, pickup trucks, SUVs, and vans. Tier 2 vehicles are 77 to 95 percent cleaner than previous models.
To lessen the impact of motor vehicles on air quality and public health, the Tier 3 program, like the Tier 2 program, views the vehicle and its fuel as an integrated system. Beginning in 2017, the program establishes new vehicle emissions requirements and reduces the sulfur content of gasoline to a maximum of 10ppm. Passenger cars, light-duty trucks, medium-duty passenger vehicles, and some heavy-duty vehicles will all be subject to the new vehicle regulations, which will lower tailpipe and evaporative emissions. The gasoline sulfur standard will allow for more stringent car emissions requirements and will improve the effectiveness of emissions control systems. It will also lower the emissions produced by the current fleet of automobiles.
What is the effect of high-sulphur content in fuel?
Sulfur is present in diesel fuel since it comes from the original crude oil source and can remain after refining. The sulfur in gasoline generates particles after combustion in the engine, which are a major source of air pollution and a source of engine damage.
High quantities of detergent additives were an essential component of engine oil before global efforts to improve air quality and remove sulfur from fuel to protect engine parts from sulfur damage. Detergency was so crucial that evaluating the level of detergents in an oil by the total base number was a typical approach to interpret engine oil performance or oil life (TBN).
Over the last few decades, regulations aimed at reducing vehicle emissions have drastically lowered the amount of sulfur allowed in diesel fuel. In both the United States and Mexico, the sulfur level of diesel fuel is now 97 percent lower than it was for most of the twentieth century. Ultra-low sulfur diesel, or ULSD, is the popular name for this type of fuel.
Which coal has high-sulphur content?
(2) Although Assam coals are known as low-rank coals, the occurrence of low oxygen concentration indicates that these coals should be of higher rank. (3) Although Assam coals are known as low-rank coals, the presence of low oxygen content indicates that these coals should be of higher rank.