1、Designation: D 1782 95 (Reapproved 2001)Standard Test Methods forOperating Performance of Particulate Cation-ExchangeMaterials1This standard is issued under the fixed designation D 1782; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisi
2、on, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 These test methods cover the determination of theoperating capacity of particulate cation-exchange ma
3、terialswhen used for the removal of calcium, magnesium, and sodiumions from water. It is intended for use in testing both new andused materials. The following two test methods are included:SectionsTest Method A-Sodium Cycle 8 to 14Test Method B-Hydrogen Cycle 15 to 211.2 The values given in SI units
4、 are to be regarded as thestandard. The inch-pound units given in parentheses are forinformation only.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and he
5、alth practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:D 1067 Test Methods for Acidity or Alkalinity of Water2D 1126 Test Method for Hardness in Water2D 1129 Terminology Relating to Water2D 1193 Specification for Reagent Water
6、2D 2687 Practices for Sampling Particulate Ion-ExchangeMaterials33. Terminology3.1 Definitions:3.1.1 For definitions of terms used in these test methods,refer to Terminology D 1129.3.2 Definitions of Terms Specific to This Standard: Certainterms in these test methods that relate specifically to ione
7、xchange are defined as follows:3.2.1 free mineral aciditythe quantitative capacity ofaqueous media to react with hydroxyl ions to pH 4.3.3.2.2 hydrogen cyclethe operation of a cation-exchangecycle wherein the removal of specified cations from influentwater is accomplished by exchange with an equival
8、ent amountof hydrogen ion from the exchange material.3.2.3 theoretical free mineral aciditythe free mineralacidity that would result from the conversion of the anions ofstrong acids in solution to their respective free acids.4. Summary of Test Methods4.1 Test Method A consists of repeated cycles of
9、backwash,brine regeneration, rinse, and exhaustion of the sample in theform of a bed in a transparent column. The exhausting mediumused is an ion-exchange test water.4.2 Test Method B consists of repeated cycles of backwash,acid regeneration, rinse, and exhaustion of the sample in theform of a bed i
10、n a transparent column. The exhausting mediumused is an ion-exchange test water.5. Apparatus5.1 Test Assemble (see Fig. 1), consisting of the following:5.1.1 Column, transparent, vertically supported, 25.4 6 2.5mm (1.0 6 0.1 in.) in inside diameter and approximately 1500mm (60 in.) long. The bottom
11、of the column shall be closed andprovided with an outlet of approximately 6-mm inside diam-eter. Connections shall be provided at top and bottom foradmission and removal of solutions as described in Section 10.Adequate means for measuring and regulating flow shall beprovided. Calibrate the column in
12、 such a manner that thevolume readings required by the test method can be made.Make all measurements at 25 6 5C.5.1.2 Support, for the sample, so designed that the distancefrom the sample to the column outlet is at least 50 mm. Asuggested supporting bed utilizes quartz, glass beads, or othermaterial
13、 1.5 to 3.5 mm in diameter, insoluble in the reagentsused, and retained on a corrosion-resistant screen. However,other supports such as fritted glass or polyester screens may beused at the discretion of the interested parties.6. Reagents6.1 Purity of ReagentsReagent grade chemicals shall beused in a
14、ll tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,1These test methods are under the jurisdiction of ASTM Committee D19 onWater and are the direct responsibility of Subcom
15、mittee D19.08 on Membranes andIon-Exchange Materials.Current edition approved April 15, 1995. Published June 1995. Originallypublished as D 1782 60 T. Last previous edition D 1782 91.2Annual Book of ASTM Standards, Vol 11.01.3Annual Book of ASTM Standards, Vol 11.02.1Copyright ASTM International, 10
16、0 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.where such specifications are available.4Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.6.2
17、 Purity of Water Unless otherwise indicated, refer-ences to water shall be understood to mean reagent water, TypeIV, conforming to Specification D 1193.7. Sampling7.1 To obtain a representative sample of particulate ion-exchange material, either from a shipment of new product inthe manufacturers ori
18、ginal packages or from a bed of usedmaterial, refer to Practices D 2687.7.2 Transfer the laboratory sample to a 2-L beaker and addenough water to bring the water level up to that of theion-exchange material and soak for 1 h (see Note 1). Mix thesample thoroughly and transfer a sufficient representat
19、iveportion to fill a 400-mL beaker. Use this portion of sample inthe procedure.NOTE 1Where new materials are shipped dry, follow the manufac-turers instructions for preconditioning.TEST METHOD ASODIUM CYCLE8. Scope8.1 This test method is designed to simulate operatingconditions on a sodium cycle use
20、d for the removal of calciumand magnesium and other divalent ions from water.9. Significance and Use9.1 Cation exchange materials are frequently used in thesodium form to exchange divalent and trivalent ions in theinfluent water for sodium ions on the resin sites. This processis commonly referred to
21、 as softening water since it removesthose ions that form a “hard” curd of insoluble salts with thefatty acids used in some soaps and that also precipitate whenwater is boiled. In such a process, sodium chloride is used asthe regenerant to return the cation-exchanging groups to thesodium form.9.2 Thi
22、s test method is intended to simulate the performanceof such materials in actual usage. It may be used either tocompare the performance of new materials or to compare theperformance of a material that has been used with its originalperformance.4Reagent Chemicals, American Chemical Society Specificat
23、ions, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmaceutical Convention
24、, Inc. (USPC), Rockville,MD.FIG. 1 Typical Arrangement of Apparatus for Performance Testing of Ion-Exchange MaterialsD 1782 95 (2001)29.3 Regenerant concentrations and dosages used herein aretypical for the types of materials used in this application. Ifdifferent concentrations or amounts of regener
25、ant are agreedupon by parties using this test method, this fact should bestated when the results are reported. Similarly, the test waterspecified is the agreed upon standard. Where other test watersor the water to be treated are used in the test, the analysis of thewater in terms of total solids, so
26、dium, calcium, magnesium,other di- or trivalent metals as well as the major anions presentshould be reported with the test results.10. Reagents and Materials10.1 Brine Regenerants:10.1.1 For synthetic organic ion-exchange materials:10.1.1.1 Sodium Chloride (100 g/L)Dissolve enough so-dium chloride (
27、NaCl) in water to make a solution containing ineach litre 100.0 g of NaCl.10.1.2 For all other ion-exchange materials:10.1.2.1 Sodium Chloride (50 g/L)Dissolve enough NaClin water to make a solution containing in each litre 50.0 g ofNaCl.10.2 Cation-Exchange Test Water A (10 meq/L)Dissolveenough cal
28、cium chloride (CaCl22H2O) and magnesium sul-fate (MgSO47H2O) in water to make a solution containing, ineach litre, 0.49 g of CaCl22H2O and 0.415 g of MgSO47H2O. Adjust the pH to 7.5 by the addition of Na2CO3(30 g/L)and determine the hardness of the solution in accordance withTest Method D 1126. The
29、hardness of the test water will be10.0 6 0.5 meq/L. Use the determined hardness in calculatingoperating capacity as indicated in 12.1. This test water shall beused for all tests.10.3 Hardness Test ReagentsFor reagents used in deter-mining hardness, refer to Test Method D 1126. This reagent isused on
30、ly in preparation of test water (see 10.2).10.4 Sodium Carbonate Solution (30 g/L)Dissolve 30 g ofsodium carbonate (Na2CO3) in water and dilute to 1 L.11. Procedure11.1 Adjust the temperature of the water and all solutions tobe used in this procedure to 25 6 5C and maintain thistemperature throughou
31、t the test.11.2 Fill the column approximately half full of water andadd sufficient sample to give a bed height of 750 6 75 mmabove the top of the support. To avoid drying out of theion-exchange material, maintain a layer of liquid at least 20 to30 mm deep above the top of the bed at all times during
32、 theprocedure.11.3 Backwash with water for 10 min using a flow rate thatwill maintain a 50 % expansion of the bed. If the supernatantliquid is clear at this point, proceed to 11.4. If the liquid iscloudy (indicating the presence of light, insoluble, extraneousmaterial), adjust the backwash outlet tu
33、be to a height above thebed equal to 75 % of the bed height. Continue backwashing atthe same rate until the effluent is clear.11.4 Allow the bed to settle and then drain at a rate ofapproximately 100 mL/min until the water level is 20 to 30 mmabove the top of the bed. Do not jar. Record the volume,
34、inmillilitres, of ion-exchange material. Repeat the 10-min back-wash until two successive readings of volume agree within 5mL. The average of these two readings shall be the samplevolume for new materials shipped in the sodium form.11.5 Exhaust the ion exchanger with cation-exchange testwater A at a
35、 flow rate of 0.33 mL/min/mL of exchanger, asmeasured in 11.4. Maintain a head of liquid not less than 50mm above the top of the bed. Continue the run until the effluentshows 0.2 meq/L (or other agreed-upon hardness level) whentested in accordance with Test Method D 1126. Record thevolume of test wa
36、ter used.11.6 Repeat the 10-min backwash and drain as described in11.3 and 11.4. When testing new material shipped in thesodium form, only one backwash is necessary at this pointbecause a determination of volume has already been made.However, used material other than in the sodium form musthave a vo
37、lume determination made here as described in 11.4.Use this sample volume determined on the exhausted materialin calculating the capacity of used ion-exchange materials.11.7 Determine the amount of brine regenerant and raterequired, from Table 1. For use with Table 1, the volumesample for new materia
38、l shall be that determined in accordancewith 11.4 and for used material shall be that determined inaccordance with 11.6.11.8 Pass the specified volume of brine regenerant throughthe bed at the specified rate until only a 20 to 30-mm layer ofliquid remains above the bed. Rinse the bed with water, usi
39、ngthe same rate, until one bed-volume of liquid has beendisplaced. Increase the rinse rate to approximately 100 mL/min. Test for hardness at 3-min intervals by adding 0.5 mL ofbuffer solution to 50 mL of the effluent followed by three dropsof hardness indicator and 0.5 mL of sodium ethylendiaminetet
40、raacetate solution (1 mL = 1.0 mg CaCO3), with stirring. Ifa blue color develops, the effluent contains 0.2 meq/L or lesshardness and the rinse is completed. If the color is red, the endpoint has not been reached. Continue the rinse until the effluentshows 0.2 meq/L or less hardness.11.9 Repeat the
41、service run described in 11.5.11.10 Repeat the cycle, beginning with a single backwash(see 11.6), omitting the determination of bed volume. Continuewith a regeneration and rinse (see 11.8), and end with a servicerun (see 11.5). Repeat the cycle until each of three successiveTABLE 1 Amount of Brine R
42、egenerant Required for Use in Test Method AType of ExchangeMaterialBrine Regenerant,g/LRate of Flow, mLbrine/min/mL of exchangerContact Time,minRegeneration Levellb/ft3g/LSynthetic organic 100 0.032 30 6.00 96.1Greensand 50 0.027 15 1.25 20.0Synthetic siliceous 50 0.080 20 3.00 80.1Carbonaceous 50 0
43、.067 15 3.15 50.5D 1782 95 (2001)3runs agrees within 65 % of their average capacity as calcu-lated in accordance with Section 12.12. Calculation12.1 Calculate the operating capacity, in milliequivalentsper millilitre, of the ion exchange material ascapacity, meq/mL 5 A 3 B! / Swhere:A = hardness of
44、test water, meq/L,B = volume of test water used in service run, L, andS = volume of sample in the bed, mL. For new materials,this refers to the average volume of the material in thesodium form as determined in 11.4. For used materi-als, it is the average volume of the material in theexhausted form a
45、s determined in 11.6.12.2 Calculate the operating capacity, in kilograins of cal-cium carbonate per cubic foot as follows:capacity, kilograins of CaCO3/ft35 C 3 21.8where:C = capacity in milliequivalents per millilitre of ion-exchange material (see 12.1).13. Report13.1 Report the capacity of the tes
46、ted material as theaverage of three successive service runs that agree within65 % of their average capacity.14. Precision and Bias514.1 PrecisionPrecision was determined from the resultsof the analyses of eight operators in four labs, with triplicatedeterminations on three materials. The average val
47、ue deter-mined for each material was as follows:New Synthetic Organic 1.15 meq/mLUsed Synthetic Organic 1.03 meq/mLNew Synthetic Siliceous 0.43 meq/mL14.2 The precision of the test method varies with theoperating capacity of the material tested and may be expressedas follows:St5 0.058 CSo5 0.024 Cwh
48、ere:St= overall precision, meq/mL,So= single operator precision, meq/mL, andC = operating capacity, meq/mL.14.3 BiasBecause materials with known operating capac-ity cannot be prepared, bias cannot be determined.TEST METHOD BHYDROGEN CYCLE15. Scope15.1 This test method is designed to simulate operati
49、ngconditions on a hydrogen cycle used for the removal of allother cations from water.16. Significance and Use16.1 Cation exchange materials containing sulfonic acidgroups are frequently used in the hydrogen form to exchangehydrogen ions from the resin sites for all the cations in theinfluent water. They are then regenerated with acid to restorethe sites to the hydrogen form for reuse. This test is designedto simulate such usage.16.2 Since each cation has a specific and different exchangeequilibrium with hydrogen form exchange groups, the effi-ciency of the p
