ASTM D1782-1995(2007) Standard Test Methods for Operating Performance of Particulate Cation-Exchange Materials.pdf

1、Designation: D 1782 95 (Reapproved 2007)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 ASodium Cycle 8 to 14Test Method BHydrogen Cycle 15 to 211.2 The values given in SI units a

4、re 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 heal

5、th practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 1067 Test Methods for Acidity or Alkalinity of WaterD 1126 Test Method for Hardness in WaterD 1129 Terminology Relating to WaterD 1193 Specification for Reagent WaterD 26

6、87 Practices for Sampling Particulate Ion-ExchangeMaterials3. 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 ionexchang

7、e 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 equivalent am

8、ountof 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 backwa

9、sh,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 in a tr

10、ansparent 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 of the

11、 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 such

12、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 1.5 t

13、o 3.5 mm in diameter, insoluble in the reagentsused, and retained on a corrosion-resistant screen. However,1These test methods are under the jurisdiction of ASTM Committee D19 onWater and are the direct responsibility of Subcommittee D19.08 on Membranes andIon Exchange Materials.Current edition appr

14、oved Dec. 1, 2007. Published December 2007. Originallyapproved in 1960. Last previous edition approved in 2001 as D 1782 95 (2001).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume informa

15、tion, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Copyright by ASTM Intl (all rights reserved); Tue Apr 15 22:08:38 EDT 2008Downloaded/printed byGuo Dehua (CNIS) pur

16、suant to License Agreement. No further reproductions authorized.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 all tests. Unless otherwise indicated, it is inten

17、ded thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.3Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use witho

18、ut lessening theaccuracy of the determination.6.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean reagent water, Type IV,conforming to Specification D 1193.7. Sampling7.1 To obtain a representative sample of particulate ion-exchange material, either from a s

19、hipment of new product inthe manufacturers original 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 th

20、oroughly and transfer a sufficient representativeportion 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 simu

21、late operatingconditions on a sodium cycle used 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 re

22、sin sites. This processis commonly referred to 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 when3Reagent Chemicals, American Chemical Society Specifications , AmericanChemical Society, Washin

23、gton, 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, Inc. (USPC), Rockville,MD.FIG. 1 Typ

24、ical Arrangement of Apparatus for Performance Testing of Ion-Exchange MaterialsD 1782 95 (2007)2Copyright by ASTM Intl (all rights reserved); Tue Apr 15 22:08:38 EDT 2008Downloaded/printed byGuo Dehua (CNIS) pursuant to License Agreement. No further reproductions authorized.water is boiled. In such

25、a process, sodium chloride is used asthe regenerant to return the cation-exchanging groups to thesodium form.9.2 This 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

26、 a material that has been used with its originalperformance.9.3 Regenerant concentrations and dosages used herein aretypical for the types of materials used in this application. Ifdifferent concentrations or amounts of regenerant are agreedupon by parties using this test method, this fact should bes

27、tated 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, sodium, calcium, magnesium,other di- or trivalent metals as well as the majo

28、r 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 (NaCl) in water to make a solution containing ineach litre 100.0 g of NaCl.

29、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 calcium chloride (CaCl22H2O) and magnesium sulfate(MgSO47H2O) in water to mak

30、e a solution containing, in eachlitre, 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) anddetermine the hardness of the solution in accordance with TestMethod D 1126. The hardness of the test water will be 10.0 60.5 meq/L. Use the determined hardne

31、ss in calculating operat-ing capacity as indicated in 12.1. This test water shall be usedfor all tests.10.3 Hardness Test ReagentsFor reagents used in deter-mining hardness, refer to Test Method D 1126. This reagent isused only in preparation of test water (see 10.2).10.4 Sodium Carbonate Solution (

32、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 throughout the test.11.2 Fill the column approximately half full of water andadd suf

33、ficient 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 theprocedure.11.3 Backwash with water for 10 min using a flow rate thatwil

34、l 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 tube to a height above thebed equal to 75 % of the bed height. Continue backw

35、ashing 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, inmillilitres, of ion-exchange material. Repeat the 10-min back-wash until

36、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 flow rate of 0.33 mL/min/mL of exchanger, asmeasured in 11.4. Maintain a h

37、ead 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 water used.11.6 Repeat the 10-min backwash and drain as described in11.3 and

38、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 volume determination made here as described in 11.4.Use this sample volume de

39、termined 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 material shall be that determined in accordancewith 11.4 and for used material sha

40、ll 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, usingthe same rate, until one bed-volume of liquid has beendisplaced. Increase

41、 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 ethylendiaminetetraacetate solution (1 mL = 1.0 mg CaCO3), with stirring. IfTABLE 1 Amount o

42、f Brine Regenerant 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 80.1Carbonac

43、eous 50 0.067 15 3.15 50.5D 1782 95 (2007)3Copyright by ASTM Intl (all rights reserved); Tue Apr 15 22:08:38 EDT 2008Downloaded/printed byGuo Dehua (CNIS) pursuant to License Agreement. No further reproductions authorized.a blue color develops, the effluent contains 0.2 meq/L or lesshardness and the

44、 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 service run described in 11.5.11.10 Repeat the cycle, beginning with a single backwash(see 11.6), omitting the determination of bed volum

45、e. Continuewith a regeneration and rinse (see 11.8), and end with a servicerun (see 11.5). Repeat the cycle until each of three successiveruns agrees within 65 % of their average capacity as calcu-lated in accordance with Section 12.12. Calculation12.1 Calculate the operating capacity, in milliequiv

46、alentsper millilitre, of the ion exchange material ascapacity, meq/mL 5 A 3 B! / Swhere:A = hardness of 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

47、determined in 11.4. For used materi-als, it is the average volume of the material in theexhausted form as 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 milliequi

48、valents per millilitre of ion-exchange material (see 12.1).13. Report13.1 Report the capacity of the tested material as theaverage of three successive service runs that agree within65 % of their average capacity.14. Precision and Bias414.1 PrecisionPrecision was determined from the resultsof the ana

49、lyses of eight operators in four labs, with triplicatedeterminations on three materials. The average value 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 Cwhere:St= overall precision, meq/mL,So= single operator precision, meq/mL, andC = operating capacity, meq/mL.14.3 BiasBecause materials with known operating c