47 / 413
www.restek.com
|
1-800-356-1688
or
1-814-353-1300
| Feedback? E-mail
advantage@restek.com21
Figure 2:
Higher sample capacity is also
demonstrated by comparing peak sym-
metry. Rt®-Alumina BOND/MAPD col-
umns produce better peak shape, even
when more material is injected.
4.2
4.4
4.6
4.8
1
2
3
4
Time (min)
Figure 1:
Rt®-Alumina BOND/MAPD columns have greater absolute retention than Select Al
2
O
3
MAPD columns, resulting in greater sample
handling capacity through increased resolution.
Time (min)
2
0
4
6
8
10
12
14
9
10
11
12 13
14 15
16
17
5
6
7
8
1
2
3
4
GC_PC1213
min.
0
2
4
6
8
10
12
14
9
10 11
12
13
14
15
16
17
5
6
7,8
1
2
3
4
GC_PC1214
Columns:
50 m x 0.53 mm ID x 10 µm;
Sample:
PLOT column QA test mix (DCG# 547267);
Injection:
5 µL, split, 200 °C; Split vent flow rate: 80 mL/min;
Oven:
130 °C, isothermal;
Carrier Gas:
helium, (4.4 psi, 30 kPa);
Detector:
FID, 200 °C.
Peaks:
1. Methane, 2. Ethane, 3. Ethylene, 4. Propane, 5. Cyclopropane, 6. Propylene, 7. Acetylene, 8. Propadiene, 9.
n
-Butane, 10.
trans
-2-Butene, 11. 1-Butene, 12. Isobutene, 13.
cis
-2-Butene, 14.
Isopentane, 15.
n
-Pentane, 16. 1,3-Butadiene, 17. Methyl acetylene.
A: Rt®-Alumina BOND/MAPD
B: Select Al
2
O
3
MAPD
Higher retention results in greater
sample handling capacity and more
flexibility in sample size.
Higher sample capacity
gives good peak shape and
improved accuracy.
GC_PC1216
A: Rt®-Alumina BOND/MAPD
B: Select Al
2
O
3
MAPD
GC_PC1215
Columns:
50 m x 0.53 mm ID x 10 µm;
Sample:
PLOT column QA
test mix (DCG# 547267);
Injection:
5-250 µL, split, 200 °C; Split
vent flow rate: 80 mL/min;
Oven:
manufacturer’s recommended
temperature used for each column (Rt®-Alumina BOND/MAPD:
130 °C, Select Al
2
O
3
MAPD: 100 °C), isothermal (hold 8 min);
CarrierGas:
helium, (4.4 psi, 30 kPa);
Detector:
FID, 200 °C.
Peaks:
1. Acetylene, 2. Propadiene, 3.
n
-Butane.
Figure 3:
Higher sample capacity results in a wide linear range and accurate quantifica-
tion, even at levels that can produce tailing and incomplete separations on other MAPD
columns. (
green
= methyl acetylene,
red
= acetylene,
blue
= propadiene).
Traces of water in the carrier gas and sample will affect the retention and selectivity of alumina. If the column is exposed to
water, the retention times will shorten. Alumina columns can be regenerated by conditioning for 15-30 minutes at 200-250 °C
under normal carrier gas flow. Periodic conditioning ensures excellent run-to-run retention time reproducibility.
The maximum programmable temperature for Rt®- and MXT®-Alumina BOND/MAPD columns is 250 °C. Higher temperatures
cause irreversible changes to the porous layer adsorption properties.
tech
tip
Alumina BOND/MAPD PLOT Columns
Rt®-Alumina BOND/MAPD Columns
(fused silica PLOT)
MXT®-Alumina BOND/MAPD Columns
(Siltek®-treated stainless steel PLOT)
ID
df
temp. limits
30-Meter
50-Meter
0.32 mm 5 µm
to 250 °C
19779
19780
0.53 mm 10 µm
to 250 °C
19777
19778
3.5
”
coil
7
”
diameter
11-pin cage
ID
df
temp. limits
30-Meter
30-Meter
0.53 mm 10 µm
to 250 °C
79728-273
Poor sample capacity
results in overloaded
peaks and inaccurate
quantification.
79728