ASTM D6302-98

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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An American National Standard
Designation: D 6302 – 98
Standard Practice for
Evaluating the Kinetic Behavior of Ion Exchange Resins
This standard is issued under the fixed designation D 6302; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 5. Significance and Use
1.1 This practice is intended to evaluate changes in kinetic 5.1 This practice is intended to evaluate changes in the
performance of ion exchange resins used in mixed beds to performance of ion exchange resins used in mixed beds
produce high purity water. Within strict limitations, it also may operating as polishing systems for solutions of low ionic
be used for comparing resin of different types. This standard strength, typically, <10 mg/L dissolved solids, that are intended
does not seek to mimic actual operating conditions. Specific to produce very high purity effluents. It is recommended that
challenge solutions and conditions are specified. At the option when new resins are installed in a plant it be used to provide a
of the user, other conditions may be tested. base line against which the future performance of that resin can
1.2 This standard does not purport to address the safety be judged.
concerns, if any, associated with its use. It is the responsibility 5.2 The conditions of this test must be limiting kinetically,
of the user of this standard to establish appropriate safety and such that kinetic leakage, and not equilibrium leakage, is
health practices and determine the applicability of regulatory tested. This leakage is influenced by a combination of influent
limitations prior to use. flow velocity and concentration, as well as bed depth.
5.3 It is recommended that the practice be followed with the
2. Referenced Documents
resin ratio, flow rate, and influent quality as indicated. The
2.1 ASTM Standards: design of the apparatus permits other variations to be used that
D 1129 Terminology Relating to Water
may be more appropriate to the chemicals used in a specific
D 1193 Specification for Reagent Water plant and the nature of its cooling water, but the cautions and
D 2187 Test Methods for Physical and Chemical Properties
limitations noted in the practice must be accommodated.
of Particulate Ion-Exchange Resins 5.4 It is possible that the cation resin could experience
D 2687 Practices for Sampling Particulate Ion-Exchange
kinetics problems. In many cases, however, the anion resins are
Materials
more likely to experience the types of degradation or fouling
D 5391 Test Method for Electrical Conductivity and Resis- that could lead to impaired kinetics. Testing of field anion and
tivity of a Flowing High Purity Water Sample
cation resins together is an option, especially when historic
data on the mixed bed will be compiled. Recognize, however,
3. Terminology
that many variables can be introduced, making it difficult to
3.1 Definitions—For definitions of terms used in this prac-
interpret results or to compare to historical or new resin data on
tice, refer to Terminology D 1129.
separate components.
5.5 Provision is made for calculation of the mass transfer
4. Summary of Practice
coefficient in the Appendix X1. When such calculation is to be
4.1 An apparatus is described in which a specified volume
made, a full wet sieve analysis, as described in Test Methods
of regenerated resin sample is mixed with a corresponding new
D 2187, also is required. Electronic particle sizing may be
resin. The mixed bed then is operated at a controlled high flow
substituted if it is referenced back to the wet sieve method.
rate on an influent of known composition, and the quality of the
5.6 This practice is intended to supplement, not displace,
effluent is measured by conductivity, and if agreed upon, other
other indicators of resin performance, such as exchange capac-
appropriate analytical procedures.
ity, % regeneration, and service experience records.
6. Interferences
This practice is under the jurisdiction of ASTM Committee D-19 on Water and
6.1 Interferences in the conventional sense are minimal, but
is the direct responsibility of Subcommittee D19.08 on Membrane and Ion
variations in test conditions, such as flow rate, temperature,
Exchange Materials.
Current edition approved July 10, 1998. Published November 1998. resin ratio, particle size, column configuration, regeneration
Annual Book of ASTM Standards, Vol 11.01.
Annual Book of ASTM Standards, Vol 11.02.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D6302–98
efficiency, and influent concentrations can cause major differ- 7. Equipment
ences in performance. This practice fixes or measures these
7.1 Backwash/Separation and Regeneration Apparatus, see
variables so that true changes in resin kinetics can be demon-
Test Methods D 2187. The column should be 50-mm ID 3 600
strated accurately. Other means will be needed to investigate
or 900-mm length.
other resin or equipment problems.
7.2 Kinetics Test Apparatus (see Fig. 1):
6.2 Contaminant ions in the resins themselves, if present
7.2.1 Feed Pumps, capable of controlled delivery of 0.5 to 3
when they are loaded into the test apparatus, may impact
mL/min. One is required, the second is optional for use where
performance significantly and must be considered in the
another reagent, such as ammonia, is to be added.
interpretation of the results. If the contaminant ions are
7.2.2 Circulating Pump, capable of delivery of 1 to 1.5
different from those in the challenge solution, they may be
L/min.
determined by ion chromatography.
7.2.3 Glass Column, nominal 25-mm ID 3 600 mm. The
column shown in Fig. 1 of Test Methods D 2187 may be
6.3 A constant velocity in the range of 50–60 gpm/ft is used
to insure that flow is turbulent and there is little or no resistance modified for this purpose.
to mass transfer from the bulk solution to the resin surfaces. 7.2.4 Mixing Chamber.
This constant velocity insures the desired testing of surface 7.2.5 Conductivity Meter With Recorder and Temperature
kinetics at the boundary layer. Compensation—See Test Method D 5391.
1. Water supply, ASTM Type I
2. Mixed bed polishing column
(Required for recirc mode)
3. Polished water reservoir
(Required for recirc mode)
4. Pump
(Required for recirc mode)
5. Conductivity meter
(Required for recirc mode)
6. Flow meter
7. and 8. Feed solution reservoir
9. and 10. Proportional metering pump
11. Mixing chamber or static mixer
12. Influent sample tap
13. Test column
14. Effluent sample tap
15. Conductivity meter
16. Conductivity meter
17. Cation column
NOTE 1—Recirculation of water is optional; final effluent also can be directed to drain.
FIG. 1 Test Apparatus for Kinetics
D6302–98
7.2.6 Flow Meter—Capable of measuring flows in the range mL/min into 1 L/min flow, the concentration in the influent
of about 1 L/min. should be 1.5 mg NH /L.
7.2.7 Cation Column, nominal 25-mm ID 3 600-mm col-
NOTE 2—Caution: Ammonium hydroxide generates irritating ammo-
umn, typically with a 15–45-cm depth of resin. This column
nia vapors.
should be prepared the day before testing to allow to rinse to
8.5.2 Sodium Sulfate Feed Solution (0.9 g Na SO /L)—Dry
2 4
>17.5 MV (see 8.3).
the Na SO for 1 h at 100–105°C, then store in a desiccator.
2 4
NOTE 1—Pressure relief should be provided for this system to allow no
Weigh 0.900 g of the anhydrous sodium sulfate, and dissolve it
more pressure than the materials can tolerate, typically 50 psig or less.
in 1 L of water. Mix well. When delivered at the rate of 0.5
mL/min into 1 L/min flow, the concentration of the influent
8. Reagents
should be 0.145 mg/L Na and 0.300 mg/L SO .
8.1 Purity of Reagents—Reagents meeting the specifica-
8.6 Regenerant, Sodium Hydroxide Solution (87 g/L)—Add
tions of the Committee on Analytical Reagents of the American
345 g NaOH to 3.5 L of water with stirring. Cool and dilute to
Chemical Society may not be suitable for use in this practice.
4.0 L. This solution is caustic and liberates heat during
All reagents used should be of the highest grade commercially
dissolution. This is equivalent to 8 % NaOH by weight.
available and should be tested for both anionic and cationic
NOTE 3—This solution is intentionally stronger than typical field
impurities by ion chromatography after the feed solutions have
,
4 5 processes so that maximum % regeneration is achieved.
been prepared.
8.2 Purity of Water—Unless otherwise indicated, references
Reagent grade 50 % NaOH (763 g NaOH/L) also can be
to water shall be understood to mean reagent water conforming
used and would require 456 mL to make 4.0 L.
to Specification D 1193, Type I. It shall be checked by ion
8.7 Regenerant, Hydrochloric Acid Solution (1 + 9)—
chromatography at the ppb level prior to use, if ion chroma-
Carefully pour 200 mL of hydrochloric acid (HCl, sp. gr. 1.19)
tography will be used for analysis.
into 1800 mL of water, stirring constantly. Cool to 256 5°C.
8.3 Standard Cation Resin—New hydrogen-form, strong
NOTE 4—For field cation samples, sulfuric acid typically would be
acid, cation resin is to be used; nuclear grade is preferred. Do
substituted for HCl, since H SO is the usual regenerant in the field.
2 4
not regenerate this resin. This resin should be stored in
impermeable containers at temperatures that do not exceed 9. Sampling
25°C. Backwash the resin with water at 100 % expansion for at
9.1 Collect the sample in accordance with Practices D 2687.
least 15 min. The resin should be rinsed thoroughly with water
It is extremely important that the resin sample properly
to $ 17.5 MV resistivity before being used in a kinetics test.
represent the entire bed being evaluated. Core sampling is
The same cation resin may be used in the test column, as well
required. A sample containing at least 300 mL of anion, or
as the cation column. It is recommended that a specific type
cation resin, or both, must be provided. The sample may be
and brand of resin be used consistently where results are to be
taken before or after separation of a mixed bed, so long as it is
compared.
representative. Use a plastic or glass container with a water-
8.4 Standard Anion Resin—Use new, hydroxide-form,
tight cap and label in accordance with Practices D 2687.
strong base anion resin; nuclear grade preferred. Follow other
9.2 Subsamples taken in the laboratory also must be taken
requirements as given in 8.3.
by careful coring to preserve the representativeness of the
8.5 Test Solutions—Test solutions can be modified for
sample.
specific systems, however, the following are recommended for
routine testing. Although a target feed injection rate of 0.5
10. Backwash and Separation Procedure
mL/min is used here, the feed concentrations and metering
10.1 Place about 800 mL of mixed bed resin sample or
pump flows can be altered, so long as the test column influent
about 500 mL of individual resin sample in the backwash/
concentrations and flow rate are nominal as specified.
separation apparatus. Backwash with water at a flow sufficient
8.5.1 Ammonia Feed Solution (3.0 g/L as NH ) Optional for
to give about 50 % bed expansion. This should allow crud to
Use with Ammoniated Systems—Tare a beaker with about 50
rinse away while separating any cation from the anion in the
mL of water on an analytical balance with 0.01-g sensitivity.
sample.
Add 20.9 g of concentrated ammonium hydroxide (sp. gr. 0.90)
10.2 Using a siphon or aspiration assembly, remove and
from a dropping bottle. Transfer to a 2-L volumetric flask, and
collect the resin of interest, anion resin (above the interface) or
dilute to volume. Mix well. When delivered at the rate of 0.5
cation resin. Try to minimize cross-contamination by leaving
behind or wasting resin as needed. This, however, must be
minimized in order to avoid sample bias. Inspection of the
Reagent Chemicals, American Chemical Society Specifications, American
interface with a hand lens may show a bead size variation at the
Chemical Society, Washington, DC. For suggestions on the testing of reagents not
interface. If less than 300 mL of the resin of interest is
listed by the American Chemical Society, see Analar Standards for Laboratory
recovered, repeat 10.1 with another portion of sample.
Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia
10.3 Remove a small amount of the separated resin to a
and National Formulary, U.S. Pharmaceutical Convention, Inc. (USPC), Rockville,
MD.
plastic petri dish and examine under low power (12–15X)
McNulty J. T., Bevan C. A., et al., “Anion Exchange Resin Kinetic Testing: An
magnification to estimate the percentage of whole beads. If the
Indispensable Tool for Condensate Polisher Troubleshooting,” Proceedings of the
resin is less than about 90 % whole beads, this practice should
47th International Water Conference, Engineers’ Society of Western Pennsylvania,
October 1986. not be continued.
D6302–98
NOTE 5—Ion exchange kinetics are affected by particle size and shape.
the test column. Again, a minimum amount of rinse water can
be used to facilitate the transfer.
10.4 After decanting excess water, measure, by coring, 300
mL of the separated resin in a graduated cylinder under water.
NOTE 6—If the resin is poorly mixed or contains air pockets, test results
Tap gently to settle before measuring resin. Disconnect the will be erroneous. If resin stratification or air bubbles can be seen in the
column, remove the resin to the beaker, and repeat the mixing and transfer
regeneration column, and transfer the resin as a slurry to the
steps.
column. Keep a small amount of water above the resin and try
to minimize air bubbles. Leave the bottom effluent line shut off
11.4 Fill the cation column to a depth of at least 15 cm with
while filling the column. Open it and immediately begin the
the new hydrogen-form cation resin (8.4), then reconnect it in
flow of regenerant. Regenerate the resin as follows. For anion,
the test apparatus. This column is not used if the sample tested
use NaOH regenerant solution at a flow rate of 25 mL/min for
is cation resin.
60 min, maintaining a temperature of 50°C either by jacketing
11.5 Before connecting to the test apparatus, turn on the
the column or warming the regenerant. For cation resin, use the
water supply system and allow it to recirculate or flush to drain
HCl regenerant with the same conditions, except that ambient
until the conductivity indicator reads 0.06 μS/cm or less. Adjust
temp
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