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PORTABLE ZEEMAN MERCURY ANALYZER RA-915+ WITH NEW PYROLYZER
PYRO-915+
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Atomic absorption spectrometry
Direct atomic absorption mercury determination (without any pre-treatment
procedures) in the samples with complex matrix (foods, vegetation,
oil and its products, soils, sediments, various biological materials)
is complicated by presence of organic compounds. When such samples
are atomized much smoke is produced and practically in all cases
the total absorption in the cell is out of the working range of
the spectrometer. Using a spectrometer with background correction
- Zeeman atomic absorption mercury spectrometer RA-915+ and a
developed two-chamber catalyst atomizer (PYRO-915+), the
direct mercury determination problem is solved.
After inserting the sample in the first chamber of the atomizer
it is heated up to 800 C (all mercury compounds are known to be
dissociated at such temperatures). Less volatile mercury compounds
are dissociated but more volatile species, e.g. mercury organic
compounds, can leave the first chamber as compounds during warming
up of the chamber. In addition presented organic compounds of
the matrix originate much smoke and variously compounds, which
are able to produce strong background absorption in the analytical
cell. All products are transported from the first chamber to the
second one by the carried gas (in our case it is air). The second
chamber is continuously heated about 800 C. There, all mercury
compounds are dissociated and smoke and interference compounds
are burst producing mostly carbon dioxide and water. Zeeman corrector
of the spectrometer eliminates the rest background absorption.
The catalyst improves the efficiency of oxidation and dissociation
in the second chamber.
- Unique direct mercury determination (no pre-treatment procedures
required) in liquid and solid samples (including complex matrix
organic samples): waste water, blood, foodstuffs, oil and oil
products, bottom sediments, rocks etc. Mercury determination
without its preliminary accumulation on a gold trap
- Fast mercury determination without its preliminary accumulation
on a gold trap
- Broad dynamic measurement range: 4 orders of magnitude
- Variable temperature of the decomposition chamber allows selection
of optimal atomization
- Heated analytical cell rules out interferences even for a
sample with a high content of organic substances and chlorides
- Boost Heated function (stepwise heating of the atomizer) allows
to control the completeness of the mercury release from the
sample
- Monitoring the background absorption during measurement allows
effective selection of the permissible weight of samples of
any composition, thereby avoiding analysis errors
- Visualization of mercury output from the sample, user-friendly
computer interface
- Calibration coefficient is set using standard mercury-containing
sample of any composition
- Automatic support of the air flow rate, no carrier gas is
needed
The validity of the method is proved by the agreement between
the measured and certified concentrations in various standard
complex-matrix samples (see the table below). Note the excellent
consistency of the method: the discrepancies between concurrent
measurements do not exceed 10% for different sample weights.
| Reference material |
Iass,
mg |
Measured value,
ppb |
Certificate
value, ppb |
Deviation,
% |
| NIST 1630a (Coal) |
60
140 |
99
92 |
105±23 |
-9 |
| DOLT-2 (Fish liver) |
50
110 |
1860
2070 |
2140±240 |
-8 |
| DORM-1 (Fish) |
50
100 |
860
780 |
798±74 |
+4 |
| IAEA 140 (Sea plant) |
80
170 |
28
32 |
29±7 |
0 |
| BCR-150(Dry milk) |
52
96
109 |
8.4
7.9
7.9 |
9.4±1.7 |
-14 |
| BCR-184(Beef) |
29
59
100 |
2.3
2.5
3.1 |
2.6±0.6 |
0 |
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Detection limit |
| Foodstuffs |
0.5-3
μg/kg |
| Oil |
1-5
μg/kg |
| Tissues |
0.5
μg/kg |
| Plants |
0.5 μg/kg |
| Hair |
2
μg/kg |
| Soil |
0.5
μg/kg |
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| Specifications
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Sample weight |
10-500 mg |
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Upper limit of the measurement range of concentration
for a 20 mg sample |
200 mg/kg |
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Time for one measurement with air pumping rate 1 l/m |
1-5 min |
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Size and weight of analyzer |
460x210x110 mm, 7.5 kg |
| Weight
of PYRO-915+ |
17
kg |
| Dimensions
of power supply unit |
380x260x130
mm |
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Dimensions of thermal chamber unit and optical unit |
350x350x120 mm |
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Power requirements for analyzer |
100/240 Vac, 50/60 Hz, 15 W |
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Power requirements for PYRO-915+ |
100/240 Vac, 50/60 Hz, 700 W |
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· RA-915+ mercury analyzer
· PYRO-915+ unit
· A PC with OS Windows®-95 or higher version with the dedicated
software
· standard sample set
· installation and commissioning
View/Download Application notes in PDF format:
All LUMEX equipment is covered by 12-months warranty
Upon request installation and commissioning of LUMEX instruments
can be carried out on Customer's site by our service engineers.
Consultations and initial training of attendance personnel with
due account of Customer's specific needs are performed. Spare
parts are delivered and repair is made upon Customer's request
(free within the warranty period).
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