Standard Practice for Evaluating the Kinetic Behavior of Ion Exchange Resins

SIGNIFICANCE AND USE
This practice is intended to evaluate changes in the performance of ion exchange resins used in mixed beds operating as polishing systems for solutions of low ionic strength, typically, 10 mg/L dissolved solids, that are intended to produce very high purity effluents. It is recommended that when new resins are installed in a plant it be used to provide a base line against which the future performance of that resin can be judged.
The conditions of this test must be limiting kinetically, such that kinetic leakage, and not equilibrium leakage, is tested. This leakage is influenced by a combination of influent flow velocity and concentration, as well as bed depth.
It is recommended that the practice be followed with the resin ratio, flow rate, and influent quality as indicated. The design of the apparatus permits other variations to be used that may be more appropriate to the chemicals used in a specific plant and the nature of its cooling water, but the cautions and limitations noted in the practice must be accommodated.
It is possible that the cation resin could experience kinetics problems. In many cases, however, the anion resins are more likely to experience the types of degradation or fouling that could lead to impaired kinetics. Testing of field anion and cation resins together is an option, especially when historic data on the mixed bed will be compiled. Recognize, however, that many variables can be introduced, making it difficult to interpret results or to compare to historical or new resin data on separate components.
Provision is made for calculation of the mass transfer coefficient in the Appendix X1. When such calculation is to be made, a full wet sieve analysis, as described in Test Methods D 2187, also is required. Electronic particle sizing may be substituted if it is referenced back to the wet sieve method.
This practice is intended to supplement, not displace, other indicators of resin performance, such as exchange capacity, % regeneration, ...
SCOPE
1.1 This practice is intended to evaluate changes in kinetic performance of ion exchange resins used in mixed beds to produce high purity water. Within strict limitations, it also may be used for comparing resin of different types. This standard does not seek to mimic actual operating conditions. Specific challenge solutions and conditions are specified. At the option of the user, other conditions may be tested.
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.3 This standard does not purport to address the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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Publication Date
30-Apr-2009
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ASTM D6302-98(2009) - Standard Practice for Evaluating the Kinetic Behavior of Ion Exchange Resins
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D6302 − 98 (Reapproved 2009)
Standard Practice for
Evaluating the Kinetic Behavior of Ion Exchange Resins
This standard is issued under the fixed designation D6302; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope resin.The mixed bed then is operated at a controlled high flow
rateonaninfluentofknowncomposition,andthequalityofthe
1.1 This practice is intended to evaluate changes in kinetic
effluent is measured by conductivity, and if agreed upon, other
performance of ion exchange resins used in mixed beds to
appropriate analytical procedures.
producehighpuritywater.Withinstrictlimitations,italsomay
be used for comparing resin of different types. This standard
5. Significance and Use
does not seek to mimic actual operating conditions. Specific
challenge solutions and conditions are specified.At the option
5.1 This practice is intended to evaluate changes in the
of the user, other conditions may be tested.
performance of ion exchange resins used in mixed beds
1.2 The values stated in SI units are to be regarded as operating as polishing systems for solutions of low ionic
standard. No other units of measurement are included in this
strength,typically,<10mg/Ldissolvedsolids,thatareintended
standard. to produce very high purity effluents. It is recommended that
when new resins are installed in a plant it be used to provide a
1.3 This standard does not purport to address the safety
baselineagainstwhichthefutureperformanceofthatresincan
concerns, if any, associated with its use. It is the responsibility
be judged.
of the user of this standard to establish appropriate safety and
health practices and determine the applicability of regulatory
5.2 The conditions of this test must be limiting kinetically,
limitations prior to use.
such that kinetic leakage, and not equilibrium leakage, is
tested. This leakage is influenced by a combination of influent
2. Referenced Documents
flow velocity and concentration, as well as bed depth.
2.1 ASTM Standards:
D1129Terminology Relating to Water
5.3 Itisrecommendedthatthepracticebefollowedwiththe
D1193Specification for Reagent Water
resin ratio, flow rate, and influent quality as indicated. The
D2187Test Methods for Physical and Chemical Properties
design of the apparatus permits other variations to be used that
of Particulate Ion-Exchange Resins
may be more appropriate to the chemicals used in a specific
D2687PracticesforSamplingParticulateIon-ExchangeMa-
plant and the nature of its cooling water, but the cautions and
terials
limitations noted in the practice must be accommodated.
D5391Test Method for Electrical Conductivity and Resis-
5.4 It is possible that the cation resin could experience
tivity of a Flowing High Purity Water Sample
kineticsproblems.Inmanycases,however,theanionresinsare
3. Terminology
more likely to experience the types of degradation or fouling
that could lead to impaired kinetics. Testing of field anion and
3.1 Definitions—For definitions of terms used in this
cation resins together is an option, especially when historic
practice, refer to Terminology D1129.
data on the mixed bed will be compiled. Recognize, however,
4. Summary of Practice
that many variables can be introduced, making it difficult to
4.1 An apparatus is described in which a specified volume interpretresultsortocomparetohistoricalornewresindataon
ofregeneratedresinsampleismixedwithacorrespondingnew separate components.
5.5 Provision is made for calculation of the mass transfer
This practice is under the jurisdiction ofASTM Committee D19 on Water and
coefficient in the Appendix X1.When such calculation is to be
is the direct responsibility of Subcommittee D19.08 on Membranes and Ion
Exchange Materials. made, a full wet sieve analysis, as described in Test Methods
Current edition approved May 1, 2009. Published June 2009. Originally
D2187, also is required. Electronic particle sizing may be
approved in 1998. Last previous edition approved in 2004 as D6302–98 (2004).
substituted if it is referenced back to the wet sieve method.
DOI: 10.1520/D6302-98R09.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
5.6 This practice is intended to supplement, not displace,
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
other indicators of resin performance, such as exchange
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. capacity, % regeneration, and service experience records.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D6302 − 98 (2009)
6. Interferences This constant velocity insures the desired testing of surface
kinetics at the boundary layer.
6.1 Interferences in the conventional sense are minimal, but
variations in test conditions, such as flow rate, temperature,
7. Equipment
resin ratio, particle size, column configuration, regeneration
7.1 Backwash/Separation and Regeneration Apparatus, see
efficiency, and influent concentrations can cause major differ-
Test Methods D2187. The column should be 50-mm ID × 600
ences in performance. This practice fixes or measures these
or 900-mm length.
variables so that true changes in resin kinetics can be demon-
7.2 Kinetics Test Apparatus (see Fig. 1):
strated accurately. Other means will be needed to investigate
7.2.1 Feed Pumps,capableofcontrolleddeliveryof0.5to3
other resin or equipment problems.
mL/min. One is required, the second is optional for use where
6.2 Contaminant ions in the resins themselves, if present
another reagent, such as ammonia, is to be added.
when they are loaded into the test apparatus, may impact
7.2.2 Circulating Pump, capable of delivery of 1 to 1.5
performance significantly and must be considered in the
L/min.
interpretation of the results. If the contaminant ions are
7.2.3 Glass Column, nominal 25-mm ID × 600 mm. The
different from those in the challenge solution, they may be
column shown in Fig. 1 of Test Methods D2187 may be
determined by ion chromatography.
modified for this purpose.
6.3 Aconstantvelocityintherangeof50–60gpm/ft isused
7.2.4 Mixing Chamber.
toinsurethatflowisturbulentandthereislittleornoresistance 7.2.5 Conductivity Meter With Recorder and Temperature
to mass transfer from the bulk solution to the resin surfaces.
Compensation—See Test Method D5391.
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 (2009)
7.2.6 Flow Meter—Capableofmeasuringflowsintherange dilute to volume. Mix well. When delivered at the rate of 0.5
of about 1 L/min. mL/min into 1 L/min flow, the concentration in the influent
7.2.7 Cation Column, nominal 25-mm ID × 600-mm should be 1.5 mg NH /L.
column,typicallywitha15–45-cmdepthofresin.Thiscolumn
NOTE 2—Ammonium hydroxide generates irritating ammonia 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
>17.5 MΩ (see 8.3). 2 4
the Na SO for1hat 100–105°C, then store in a desiccator.
2 4
NOTE 1—Pressure relief should be provided for this system to allow no
Weigh0.900goftheanhydroussodiumsulfate,anddissolveit
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 PurityofReagents—Reagentsmeetingthespecifications
8.6 Regenerant, Sodium Hydroxide Solution (87 g/L)—Add
of the Committee on Analytical Reagents of the American
345 g NaOH to 3.5 Lof 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
impuritiesbyionchromatographyafterthefeedsolutionshave
NOTE 3—This solution is intentionally stronger than typical field
3,4
been prepared.
processes so that maximum % regeneration is achieved.
8.2 Purity of Water—Unless otherwise indicated, references
Reagent grade 50% NaOH (763 g NaOH/L) also can be
towatershallbeunderstoodtomeanreagentwaterconforming
used and would require 456 mL to make 4.0 L.
to Specification D1193, 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 mLof 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.Backwashtheresinwithwaterat100%expansionforat
9.1 Collect the sample in accordance with Practices D2687.
least 15 min.The resin should be rinsed thoroughly with water
to ≥ 17.5 MΩ resistivity before being used in a kinetics test. It is extremely important that the resin sample properly
represent the entire bed being evaluated. Core sampling is
The same cation resin may be used in the test column, as well
as the cation column. It is recommended that a specific type required. A sample containing at least 300 mL of anion, or
cation resin, or both, must be provided. The sample may be
and brand of resin be used consistently where results are to be
compared. taken before or after separation of a mixed bed, so long as it is
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 D2687.
strong base anion resin; nuclear grade preferred. Follow other
requirements as given in 8.3. 9.2 Subsamples taken in the laboratory also must be taken
by careful coring to preserve the representativeness of the
8.5 Test Solutions—Test solutions can be modified for spe-
sample.
cific 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
pump flows can be altered, so long as the test column influent
10.1 Place about 800 mL of mixed bed resin sample or
concentrations and flow rate are nominal as specified.
about 500 mL of individual resin sample in the backwash/
8.5.1 Ammonia Feed Solution (3.0 g/Las NH ) Optional for
3 separation apparatus. Backwash with water at a flow sufficient
Use with Ammoniated Systems—Tare a beaker with about 50
to give about 50% bed expansion. This should allow crud to
mL of water on an analytical balance with 0.01-g sensitivity.
rinse away while separating any cation from the anion in the
Add20.9gofconcentratedammoniumhydroxide(sp.gr.0.90)
sample.
from a dropping bottle. Transfer to a 2-Lvolumetric flask, and
10.2 Using a siphon or aspiration assembly, remove and
collecttheresinofinterest,anionresin(abovetheinterface)or
cation resin. Try to minimize cross-contamination by leaving
Reagent Chemicals, American Chemical Society Specifications, American
behind or wasting resin as needed. This, however, must be
Chemical Society, Washington, DC. For suggestions on the testing of reagents not
listed by the American Chemical Society, see Analar Standards for Laboratory
minimized in order to avoid sample bias. Inspection of the
Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia
interfacewithahandlensmayshowabeadsizevariationatthe
and National Formulary, U.S. Pharmaceutical Convention, Inc. (USPC), Rockville,
interface. If less than 300 mL of the resin of interest is
MD.
recovered, repeat 10.1 with another portion of sample.
McNulty,J.T.,Bevan,C.A.,etal.,“AnionExchangeResinKineticTesting:An
Indispensable Tool for Condensate Polisher Troubleshooting,” Proceedings of the
10.3 Remove a small amount of the separated resin to a
47th International Water Conference, Engineers’ Society of Western Pennsylvania,
October 1986. plastic petri dish and examine under low power (12–15X)
D6302 − 98 (2009)
magnification to estimate the percentage of whole beads. If the coefficient will be calculated, measure the inside diameter of
resin is less than about 90% whole beads, this practice should the test column with a micrometer, divide this by two, and
convert to meters.
not be continued.
11.3 An alternative is to drain the test column as above, but
NOTE 5—Ion exchange kinetics are affected by particle size and shape.
transfer the mixed resin in 25-mL portions, about one
10.4 After decanting excess water, measure, by coring, 300
tablespoon,toalong-stemmedplasticfunnelinsertedinthetop
mLof the separated resin in a graduated cylinder under water.
of the test column. Again, a minimum amount of rinse water
Tap gently to settle before measuring resin. Disconnect the
can be used to facilitate the transfer.
regeneration column, and transfer the resin as a slurry to the
NOTE6—Iftheresinispoorlymixedorcontainsairpockets,testresults
column. Keep a small amount of water above the resin and try
will be erroneous. If resin stratification or air bubbles can be seen in the
tominimizeairbubbles.Leavethebottomeffluentlineshutoff
column,removetheresintothebeaker,andrepeatthemixingandtransfer
while filling the column. Open it and immediately begin the
steps.
flow of regenerant. Regenerate the resin as follows. For anion,
11.4 Fill the cation column to a depth of at least 15 cm with
use NaOH regenerant solution at a flow rate of 25 mL/min for
the new hydrogen-form cation resin (8.4), then reconnect it in
60 min, maintaining a temperature of 50°C either
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