3 oxygen equivalents of common gases, Model 755a, Instruction manual – Emerson 755A User Manual
Page 43
Instruction Manual
245364-V
May 2002
Rosemount Analytical Inc. A Division of Emerson Process Management Operation 3-11
Model 755A
0 + =
0
100
[100((-0.623)-(-0.358))]-100((-0.623)-(-0.358))
100
0-100(-0.265)
100
= 0.265
21+ = 21 + = 21.21%
21+ =
21
100
[100((-0.623)-(-0.358))]-100((-0.623)-(-0.358))
100
0-211(-26.5)-(-26.5)
100
-5.565+26.5
100
Example:
Sample is oxygen in a background of
CO
2
. (Oxygen equivalent of CO
2
is -
0.623).
Standard is the following:
Pure nitrogen for ZERO gas.
21% oxygen, 79% nitrogen for SPAN gas.
(Oxygen equivalent of nitrogen is -0.358).
With nitrogen ZERO gas flowing, Adjusted
Value is the following:
Display should be made to read 0.265%
oxygen with ZERO control.
With SPAN gas (21% oxygen, 79%
nitrogen) flowing, Adjusted Value is the
following:
Display should be made to read 21.21%
oxygen with SPAN control.
In limiting cases the general equation
reduces to simpler forms:
1. If the SPAN gas is 100% oxygen,
there is no background gas and thus
no correction.
2. If the ZERO gas is oxygen-free, the
adjusted value for setting the ZERO
control becomes -((-0.623)-(-0.358)).
When the ZERO gas is more
diamagnetic than the background gas
in the sample, this difference is
negative. Use a recorder with below-
zero capability to set negative values.
GAS
EQUIV. % AS O
2
Acetylene, C
2
H
2
-0.612
Allene, C
3
H
4
-0.744
Ammonia, NH
3
-0.479
Argon, A
-0.569
Bromine, Br
2
-1.83
1,2-Butadiene C
4
H
6
-1.047
1,3-Butadiene C
4
H
6
-1.944
n-Butane, C
4
H
10
-1.481
iso-Butane, C
4
H
10
-1.485
Butene-1, C
4
H
8
-1.205
cis Butene-2, C
4
H
8
-1.252
iso-Butene, C
4
H
8
-1.201
trans butene-2, C
4
H
8
-1.274
Carbon Dioxide CO
2
-0.623
Carbon Monoxide, CO
-0.354
Ethane, C
2
H
6
-0.789
Ethylene, C
2
H
4
-0.553
Helium, H
e
-0.059
n-Heptane, C
7
H
16
-2.508
n-Hexane, C
6
H
12
-2.175
cyclo-Hexane, C
6
H
12
-1.915
Hydrogen, H
2
-0.117
Hydrogen Bromide, Hbr
-0.968
Hydrogen Chloride, HC1
-0.651
Hydrogen Fluoride, HF
-0.253
Hydrogen Iodide, HI
-1.403
Hydrogen Sulphide, C
2
S
-0.751
Kryton, Kr
-0.853
Methane, CH
4
-0.512
Neon, Ne
-0.205
Nitric Oxide, NO
+44.2
Nitrogen, N
2
-0.358
Nitrogen Dioxide, NO
2
+28.7
n-Octane, C
8
H
18
-2.840
Oxygen, O
2
+100.0
n-Pentane, C
5
H
12
-1.810
iso-Pentane, C
5
H
12
-1.853
neo-Pentane, C
5
H
12
-1.853
Propane, C
3
H
8
-1.135
Propylene, C
3
H
6
-0.903
Water, H
2
O
-0.381
Xenon, Xe
-1.340
Table 3-3.Oxygen Equivalents of Common Gases