Thermo Scientific SOLA II, User Manual

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Product Overview
Total Sulfur Measurement
2-2 SOLA II User Guide Thermo Fisher Scientific
Note
Liquid samples with high vapor temperatures such as naphthas and
gasolines will require sample backpressure regu0 25–35 psig.
σ
λ
Remove undissolved water.
Sample should be delivered to the sample conditioning system using a sample
probe. The sample probe should be designed and fabricated so that sample is
extracted from near the center of the process pipe, preventing the
unnecessary introduction of pipe scale and other particulate that tend to
accumulate along the process pipe walls.
Figure 2–1. Functional block diagram
Total sulfur measurement is based upon the precise measurement of the SO
2
concentration produced from a wide variety of compounds containing sulfur,
such as H
2
S, COS, methyl mercaptan, benzothiophenes, dibenzothiophenes,
sulfides, disulfides, and thiols. Consider the measurement of a sample of
diesel, gasoline, or another common petroleum fraction such as naphtha for
liquid phase samples. For liquid phase samples, the analyzer periodically
injects a very small quantity of sample (1.0 µL) of the petroleum fraction into
a hot oven (110°C to 220°C / 230°F to 428°F) where it is vaporized and mixed
with air. Analysis of gas phase samples requires sample sizes of 0.1 to 1.0 cm
3
.
After thoroughly mixing with air, the sample enters the pyrolyzer, where all
components of the sample are combusted at 1100°C (2012°F) to CO
2
, H
2
O, or
SO
2
. The quantity of SO
2
formed during the combustion process is directly
proportional to the total sulfur content of the petroleum fraction.
The analyzer is equipped with a PUVF detector that accurately measures the
quantity of SO
2
formed during the combustion process. The SO
2
molecules
Total Sulfur
Measurement