Agilent Technologies G2747A User manual

Agilent Technologies
Agilent G2747A
Nickel Catalyst Kit
6890 Gas Chromatograph
Installation Guide

2 Nickel Catalyst Kit Installation Guide
Notices
© Agilent Technologies, Inc. 2002
No part of this manual may be reproduced in
any form or by any means (including elec-
tronic storage and retrieval or translation
into a foreign language) without prior agree-
ment and written consent from Agilent
Technologies, Inc. as governed by United
States and international copyright laws.
Manual Part Number
G2747-90107
Edition
First edition, August 2002
Replaces part number G2747-90100
Printed in USA
Agilent Technologies, Inc.
2850 Centerville Road
Wilmington, DE 19808-1610 USA
Safety Notices
CAUTION
A CAUTION notice denotes a haz-
ard. It calls attention to an operat-
ing procedure, practice, or the like
that, if not correctly performed or
adhered to, could result in damage
to the product or loss of important
data. Do not proceed beyond a
CAUTION notice until the indicated
conditions are fully understood and
met.
WARNING
A WARNING notice denotes a
hazard. It calls attention to an
operating procedure, practice, or
the like that, if not correctly per-
formed or adhered to, could result
in personal injury or death. Do not
proceed beyond a WARNING
notice until the indicated condi-
tions are fully understood and
met.

3
Agilent G2747A Nickel Catalyst Kit
Installation and Maintenance
Agilent Technologies
Installation and Maintenance
The Nickel Catalyst Kit, accessory G2747A, is used on the 6890
Series gas chromatograph for trace analysis of CO and CO2with
a flame ionization detector (FID). The gas sample is separated
on the column and passed over the hot catalyst in the presence
of hydrogen, which converts the CO and CO2peaks to CH4.
Requirements
•An available inlet position. The accessory is usually installed
in the back position. If you remove an existing inlet system to
make space, be sure to remove its flow module as well.
•Two nut plates (part no. 05890-80660) installed in the oven.
They are provided with Heated Valve Box kits G1580A and
G1581A.
•The packed/capillary (universal) version of the FID.
Gas sample valve Column Nickel catalyst FID
Carrier gas
Hydrogen Air
Sample

4 Nickel Catalyst Kit Installation Guide
Installation and Maintenance
Table 1 Kit contents
Kit G2747A Qty.
Nickel catalyst assembly 1
Porapak Q column 1
Inlet tube with bulkhead
fitting
1
Retaining nut 1
Block insulation 1
Top cover 1
Cup 1
Insulation ring 3
Locating pin 1
Brass plug, 1/8-inch 1
O-ring 3
Nut and ferrule set,
1/8-inch stainless steel
1
Screw, M4 x 12 mm,
chrome-plated
5
Screw, M4 x 16 mm 1
Performance evaluation
sample, can
1
Installation sheet (this
document)
1

Installation and Maintenance
Nickel Catalyst Kit Installation Guide 5
Part identification
Tools required
•Torx™ T-20 drive
•Flat blade screwdriver
•Open end wrenches
Porapak Q column
Top cover
Nickel catalyst assembly
NCT inlet tube with bulkhead fitting
Retaining nut
Block insulation
Cup
Insulation ring
Locating pin
Brass plug
O-rings
Nut and ferrule set
Screws, M4 x 12 mm
Screw, M4 x 16 mm
Insulation rings
Gang block fitting
Hydrogen supply tube
Exit tube

6 Nickel Catalyst Kit Installation Guide
Installation and Maintenance
Prepare the instrument
1Turn off the oven and heated zones and let them cool.
2Turn off all gases at their source.
3Turn the main power line switch off.
4Unplug the line power cord.
5Remove the column. Remove any hardware attached to the
FID (liner, column/liner nuts, ferrules, makeup gas adapter,
etc.).
WARNING Hydrogen (H2) is flammable and is an explosion hazard when mixed
with air in an enclosed space (for example, the oven). In any
application using H2, turn off the supply at its source before working
on the instrument.

Installation and Maintenance
Nickel Catalyst Kit Installation Guide 7
6If a 7683 autosampler is installed:
aLift the injector from the GC mounting post and set it
aside.
bRemove the tray by loosening/removing the three
mounting screws.
cProceed to step 8.
Tray mounting
screws

8 Nickel Catalyst Kit Installation Guide
Installation and Maintenance
7If a 7673 autosampler is installed:
aRemove the tray from the autosampler.
bLift the autosampler from its mounting bracket and set it
aside.
cRemove two screws underneath the autosampler bracket.
dRemove two screws holding the tray mounting strap.
eRemove six screws on top of the bracket. Lift the bracket
off.

Installation and Maintenance
Nickel Catalyst Kit Installation Guide 9
8Remove the injection port cover, if present, by loosening five
Torx T-20 screws and lifting it up.
9Loosen the two screws on the top edge of the left side panel.
Slide the panel slightly to the rear and lift it off.
10 Remove the electronics carrier top cover by grasping it at the
back edge and lifting upwards until its catch releases, then
pull it towards the back of the instrument.
11 Remove the top part of the back panel.
12 Remove the pneumatics cover and the RFI shield underneath
it.
Install the Nickel Catalyst Tube (NCT)
These instructions assume that you are installing the NCT in the
back inlet position.
CAUTION The insulation on the GC is made of refractory ceramic fibers (RCF).
Ventilate your work area. Wear long sleeves, gloves, safety glasses,
and a disposable dust/mist respirator. Dispose of insulation in a sealed
plastic bag.

10 Nickel Catalyst Kit Installation Guide
Installation and Maintenance
1If present, remove the cover plate from the back inlet
mounting location and remove the pre-cut insulation below
it.
2Install the block insulation in the back inlet position.
3Prepare the NCT by bending the hydrogen supply tube and
the NCT exit tube along the side of the catalyst chamber.
4Install the NCT in the block insulation with the column
fitting and exit tube inside the oven. Avoid getting insulation
inside the exit tube. Feed the heater/sensor cable out the top.
5Use the removed insulation (tear apart as needed) to fill any
space around the NCT.
6Remove the center plug from one insulation ring. Place the
insulation ring on top of the NCT. Install the cover plate on
top of the ring and secure with three screws.
7Remove the plugs from the remaining insulation rings. Place
the rings in the insulation cup. Install the cup inside the
oven over the NCT exit tube and the bottom fitting. Avoid
getting insulation inside the exit tube. Secure the cup to the
oven with two screws.
Hydrogen supply tube
NCT exit tube (to FID)
Column fitting
Heater/sensor cable

Installation and Maintenance
Nickel Catalyst Kit Installation Guide 11
8Connect the NCT exit tube to the FID inlet. Assemble a
1/8-inch stainless steel nut and front and back ferrule onto
the tube. Fully insert the tube, ferrules, and nut into the FID
base. Tighten the nut finger-tight, then use a wrench to
tighten the nut an additional 1/2 to 3/4 turn.
9Install the bulkhead fitting end of the inlet tube to the nut
plate on the right side of the oven. Secure with the retaining
nut.
10 Connect the NCT inlet tube to the fitting on the bottom of the
NCT. Assemble a 1/8-inch stainless steel nut and front and
back ferrule onto the tube. Fully insert the tube, ferrules, and
nut into the NCT fitting. Tighten the nut finger-tight, then
use a wrench to tighten the nut an additional
1/2 to 3/4 turn.
11 Install the Porapak Q column between the gas sample valve
fitting on the inlet side of the oven and the NCT inlet tube on
the detector side of the oven.
Gas sample valve fitting
Retaining nut
Porapak Q column
NCT inlet tube
NCT exit tube
Nut plate

12 Nickel Catalyst Kit Installation Guide
Installation and Maintenance
12 Turn off the hydrogen at its source. Locate the flow
manifold that feeds the FID being used.
13 Disconnect the manifold gang block fitting from the manifold.
14 Use pliers to remove the locating pin protruding from the
face of the manifold gang block fitting. Replace it with the
longer pin supplied in this kit.
15 Place the NCT gang block fitting, with three O-rings, on the
manifold. Place the manifold gang block fitting, also with
WARNING Hydrogen (H2) is flammable and is an explosion hazard when mixed
with air in an enclosed space (for example, the oven). In any
application using H2, turn off the supply at its source before working
on the instrument.
To NCT
To FID
Manifold (one of two possible types)
Locating pin
O-rings
M4 x 16 mm screw
Manifold gang block fitting
NCT gang block fitting

Installation and Maintenance
Nickel Catalyst Kit Installation Guide 13
O-rings, on top of it and secure with the long screw from this
kit.
16 Route the heater/sensor cable through the channel to the left
and under the clip. Plug it into the back inlet connector.
17 Restore gas flows and leak test the new installation.
18 Reinstall the panels and covers. Reconnect the instrument
power cord and restore power.
Verifying performance
1If any heated zone is turned on, turn it off and allow it to
cool. DO NOT heat any heated zone.
2Set the gas flow rates.
Channel
Clip
Back inlet
connector
Table 2 Gas flow rates for a standard FID installation
Gas Flow rate, mL/min
Carrier (helium) 30
FID hydrogen 30
FID air 400

14 Nickel Catalyst Kit Installation Guide
Installation and Maintenance
3Allow helium and hydrogen to flow through the system for
15 minutes.
4Carefully check the column and supply fittings for leaks. Air
leaks can damage the catalyst.
5Set the nickel catalyst tube temperature (back inlet
temperature) to 375°C and the FID temperature to 300°C.
Allow them to condition for one hour. While the zones are
heating, ignite the FID flame.
6After 1 hour, set the following temperatures:
Table 3 Gas flow rates for a TCD/FID in-series installation
Gas Flow rate, mL/min
Carrier (helium) 30
TCD switching flow 25
FID hydrogen 45
FID air 500
CAUTION Hydrogen flow is pressure-controlled, where an FID provides a known
resistance. The NCT increases flow resistance, so that the calibration
is no longer valid. You must measure hydrogen flow with a bubble or
similar meter. See your GC Operating Manual for details.
Zone °C
Oven 35
FID as desired
Nickel Catalyst 375
TCD (if in use) as desired

Installation and Maintenance
Nickel Catalyst Kit Installation Guide 15
When the temperatures have stabilized, the system is ready
for use.
7Load the valve sample loop with the nickel catalyst
performance evaluation sample (a quick press of the can
button) and start the run. The chromatogram should be
similar to the one in the figure. (CO2may be larger due to the
presence of air in the sample.)
START
STOP
IF
1.484 CO
2.085 CH4
3.926 CO2

16 Nickel Catalyst Kit Installation Guide
Installation and Maintenance
Repacking the catalyst
The nickel catalyst can be damaged by exposure to air. If
performance is significantly degraded, repack the catalyst tube.
1Turn off the back inlet thermal zone. Turn off all other
heaters. When the NCT has cooled to room temperature,
turn off the power to the GC and disconnect the power cord.
Bleed down the residual hydrogen and carrier gas pressures.
2Remove the three screws holding the cover plate on top of the
NCT. Remove the plate and the insulation around the NCT.
3From inside the oven, loosen the two screws holding the
insulation cup. Remove the cup and insulation.
4Use two wrenches to disconnect the H2mix weldment from
the bottom of the catalyst assembly. Be careful NOT to place
WARNING Hydrogen (H2) is flammable and is an explosion hazard when mixed
with air in an enclosed space (for example, the oven). In any
application using H2, turn off the supply at its source before working
on the instrument.
Both nickel oxide and some forms of silicon oxide are considered
carcinogens for humans. Perform all work in a fume hood and wear
cotton gloves at all times. Remove any spills with an HEPA-type
vacuum cleaner, avoiding any action that raises dust. Alert your
company’s Safety group if a spill occurs.
Due to the possibility of dermatitis, wash the arms and hands with
soap and water after use. Long sleeves are recommended during any
use and spill cleanup. If long sleeves are not worn, long gloves are
an acceptable substitute.
CAUTION Be sure to read the Material Safety Data Sheet (MSDS) provided with
the catalyst before performing this procedure.

Installation and Maintenance
Nickel Catalyst Kit Installation Guide 17
stress on the 1/16-inch tube. Stress can damage the
weldment.
5Use two wrenches to disconnect the reducer from the top of
the catalyst assembly.
6Gently lift the catalyst assembly out of the injection area.
Both ends of the catalyst tube are now accessible.
7Use a hooked instrument to remove the glass wool plug from
the bottom of the tube. Make sure you get all of it.
8Empty the old catalyst from the tube (you may have to break
it out with a pointed tool). Make sure you get it all out.
9Use a thin rod to push out the top glass wool plug from the
tube.
10 Clean the inside of the tube thoroughly with methanol. Do
not use any sharp metal tools on the inside of the tube. A
cotton swab carefully used will ensure cleanliness. Dry the
tube.
Packed cat tube assembly
H2mix weldment
Reducer
Packed catalyst assembly
Packed
area

18 Nickel Catalyst Kit Installation Guide
Installation and Maintenance
11 The previous figure shows the dimensions for repacking the
tube correctly. If any catalyst is outside the heated zone,
severe tailing of CO will result.
Prepare a simple depth gauge using a wooden cotton swab or
any other handy rod or tubing. Use tape or paint to mark the
stick at 46 mm from the blunt end and at 22 mm from the
blunt end.
12 Roll up a piece of glass wool about the size of a large pea.
Push this into the tube from the 1/4-inch end and seat it
firmly. Measure the depth of this glass wool with the depth
gauge—it should be 46 mm from the end of the tube. If
necessary, add more glass wool. A slight compression of the
glass wool during the measurement works best. The goal is to
position the catalyst within the heated block area. Catalyst
outside this area can create tailing peaks.
13 Turn the catalyst assembly upside down and add catalyst
slowly. Tap gently to help seat it. When the catalyst is 22 mm
from the end, stop adding catalyst. Do NOT crush the
catalyst when packing or measuring the depth.
14 Add a single glass wool plug to fill the remaining part of the
tube to within 5 mm of the end. This plug should be gently
compressed during installation.
15 Reassembly is the reverse of steps 1 through 6.
Make sure that the insulation is carefully repacked around
the tube before you reinstall the injector cover plate and the
insulation cup.
16 Leak test the new installation.
CAUTION Before installing the catalyst assembly into the oven, carefully wipe it
to remove any catalyst dust.
WARNING Hydrogen (H2) is flammable and is an explosion hazard when mixed
with air and confined in an enclosed space (for example, the oven).

Installation and Maintenance
Nickel Catalyst Kit Installation Guide 19
17 Start the carrier and hydrogen flows. Allow them to flow for
15 minutes.
18 Heat the nickel catalyst to 375°C and hold for 1 hour.
The accessory is ready for use.

Agilent Technologies, Inc.
Printed in USA, August 2002
Agilent Technologies
G2747-90107