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Appendix C
Column and trap cleaning procedure
Apparatus
1.
LC system
- Dionex ICS-3000 or 5000 consisting of a SP, DP, WPS-3000 (TB, P or S), and an electrochemical cell with
a gold working electrode (p/n 079850) and combination pH Ag/AgCl reference electrode (p/n 061879). Utilizing
Chromeleon 6.80 or equivalent.
2.
Analytical Column
–
Analytical column, Thermo CarboPac PA1, 250x4mm (p/n 035391); borate trap (placed instead of
a guard column), Thermo p/n 047078.
3.
Analytical Balance
–
readability to 0.01 mg recommended.
Reagents
1.
Lab water
- ASTM Type 1 water.
2.
50% w/w NaOH
(Fisher p/n SS254-500).
3.
Sodium Acetate trihydrate
(Sigma p/n 71188).
Instrument Conditions
1.
Disconnect the end of the columns from the electrochemical detector and drain directly to waste bypassing the detector.
2.
Place the borate trap AFTER the analytical column so as to avoid flushing the contamination onto the analytical column.
Maintain the proper flow direction of the columns. DO NOT REVERSE THE FLOW OF EITHER COLUMN.
3.
Wash the columns with the gradient shown below in table C-1 with the effluent going to waste.
4.
Replace the borate trap BEFORE the analytical column and equilibrate the columns with the gradient from part 2 for 20
minutes with the effluent going to waste.
5.
Connect the analytical column outlet to the electrochemical cell and equilibrate the HPAEC-PAD system according to part
2 above.
Table C-1
Column Cleaning Gradient*
Time (min)
Flow
(ml/min)
%C
%D
Curve
0
1.0
40.0
0.0
NA
0
1.0
40.0
0.0
5
15.0
1.0
40.0
0.0
5
15.1
1.0
40.0
60.0
5
30.0
1.0
40.0
60.0
5
30.1
1.0
40.0
0.0
5
45.0
1.0
40.0
0.0
5
*B line not used in this separation, remainder to make up 100% is from line “A” (lab water)
Fos-04 (February 2016)
FOR ERP USE ONLY
DO NOT DISTRIBUTE