Waters IC-Pak Column and Guard - Manual (Page 6)

[ Care and Use ManUal ]
IC-Pak Column and Guard Column 6
Temperature:
* Do not exceed a flow rate of 1.0 mL/min for the IC-Pak A HR
column. Flow rates higher than this may damage the column and will
void the warranty.
General Considerations:
• Sodium silicate leaching from glass vials will cause artifacts when
analyzing anions or cations. Plastic containers should be used for all
solutions.
• Dedicate columns to one eluent only, if possible. Multiple eluent
changes may result in shortened column life. Dedicated columns should
be used for either monovalent or divalent cation analysis.
• Filter all aqueous buffers. Do not use turbid or cloudy buffers.
• Remove aliquots from the sample container for pH readings, and then
dispose of the contaminated aliquots.
• Use a pH meter to measure the pH of eluents.
• Protect columns from vibration, mechanical shock, and rapid changes
in pressure, flow rate or solvent composition. Any thermal, physical or
chemical shock (such as changing solvents rapidly or at high flow rates)
can cause a loss of efficiency.
• When using water, treat with a Milli-Q water system capable of deliver-
ing 18 megohm water. Neither deionized water nor HPLC grade bottled
water is acceptable because each may contain organic compounds
which alter column selectivity.
• DO NOT inject concentrated samples directly into the eluent. Direct
injection may cause precipitation of the salts in the sample. Dissolve
(or dilute) samples in an appropriate volume of the eluent first. If other
solvents must be used, be sure no precipitation occurs upon injection
into the eluent. Always filter samples before use.
• Highly concentrated samples (greater than 100 ppm per ion) may yield
poor peak shape due to overloading the column. Dilute the sample
before injection. When analyzing an unknown, prepare a 1:100 dilution
as a first step in optimizing the method.
b. Efficiency Testing
Waters columns are tested for adherence to Waters specifications.
Slight variations in results will occur depending on:
• Equipment used
• Test sample makeup
• Equipment settings and conditions
Perform an initial efficiency test before attempting the first analysis.
Run the test sample using the calibration standards detailed in the
following pages and record the results (retention time and the set-
tings used).
The initial efficiency test is performed by:
1. Preparing the eluent (Section III, a)
2. Preparing the calibration standards (Section IV, b to Section IV, d)
3. Running the calibration standard and determining column efficiency
(Section IV, e)
If problems occur during normal operation of the column, repeat the
conditions for the initial efficiency test and compare the results. Dif-
ferences in the results may indicate the source of the problem.
c. Anion Calibration Standard Preparation
1. To prepare individual 1000 ppm (mg/L) stock standards, refer to Table
4 for the weight of salt required. Select the highest purity salt available,
weigh the specified amount, and add to a 1 liter volumetric flask.
Table 4: Salt Weight for Anion Stock Solution Preparation
Anion (expressed as
compound listed)
Compound Weight in grams
F - NaF 2.2101
CI - NaCl 1.6485
Br - NaBr 1.2877
NO
3
- NaNO
3
1.3708
HP0
4
-2 KH
2
PO
4
1.4179
SO
4
-2 Na
2
SO
4
1.4787
Normal operation 25 °C
Limits 10 °C - 50 °C