ASTM D1782-17 Standard Test Methods for Operating Performance of Particulate Cation-Exchange Materials.pdf

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1、Designation: D1782 17Standard Test Methods forOperating Performance of Particulate Cation-ExchangeMaterials1This standard is issued under the fixed designation D1782; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last

2、 revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () 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 materialswhen used for

3、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 stated in SI units are to be regarded as

4、standard. The values given in parentheses are mathematicalconversions to inch-pound units that are provided for informa-tion only and are not considered standard.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the u

5、ser of this standard to establish appro-priate safety, health and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in

6、 the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D1067 Test Methods for Acidity or Alkalinity of WaterD1126 Test Method f

7、or Hardness in WaterD1129 Terminology Relating to WaterD1193 Specification for Reagent WaterD2687 Practices for Sampling Particulate Ion-Exchange Ma-terials3. Terminology3.1 Definitions:3.1.1 For definitions of terms used in these standards, referto Terminology D1129.3.2 Definitions of Terms Specifi

8、c to This Standard:3.2.1 Certain terms in these standards that relate specificallyto ion exchange are defined as follows:3.2.2 free mineral aciditythe quantitative capacity ofaqueous media to react with hydroxyl ions to pH 4.3.3.2.3 hydrogen cyclethe operation of a cation-exchangecycle wherein the r

9、emoval of specified cations from influentwater is accomplished by exchange with an equivalent amountof hydrogen ion from the exchange material.3.2.4 theoretical free mineral aciditythe free mineral acid-ity that would result from the conversion of the anions ofstrong acids in solution to their respe

10、ctive free acids.4. Summary of Test Methods4.1 Test Method A consists of repeated cycles of 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 cyc

11、les of backwash,acid 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.5. Apparatus5.1 Test Assemble (see Fig. 1), consisting of the following:5.1.1 Column, transparent, vertically supported, 25.4 6

12、2.5mm (1.0 6 0.1 in.) in inside diameter and approximately 1500mm (60 in.) long. The bottom 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 1

13、0.Adequate means for measuring and regulating flow shall beprovided. Calibrate the column in 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

14、 is at least 50 mm. A1These 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 approved Aug. 1, 2017. Published August 2017. Originallyapproved in 1960. Last previous ed

15、ition approved in 2009 as D1782 95 (2009).DOI: 10.1520/D1782-17.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM websi

16、te.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of In

17、ternational Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1suggested supporting bed utilizes quartz, glass beads, or othermaterial 1.5 to 3.5 mm in diameter, insoluble in the reagentsused, and retained on a corrosion-resistan

18、t 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 all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the spec

19、ifications 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 without lessening theaccuracy of the determination.

20、6.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean reagent water, Type IV,conforming to Specification D1193.7. Sampling7.1 To obtain a representative sample of particulate ion-exchange material, either from a shipment of new product inthe manufacturers orig

21、inal packages or from a bed of usedmaterial, refer to Practices D2687.7.2 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 representativ

22、eportion 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 used

23、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 the3Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society,

24、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, Inc. (USPC), Rockville,MD.FIG.

25、 1 Typical Arrangement of Apparatus for Performance Testing of Ion-Exchange MaterialsD1782 172influent water for sodium ions on the resin 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 so

26、me 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 This test method is intended to simulate the performanceof such materials in actual usage. It may be used either tocompare

27、the performance of new materials or to compare theperformance of 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 ag

28、reedupon 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, sodium, calc

29、ium, 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 (NaCl) in w

30、ater 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 calcium chlor

31、ide (CaCl22H2O) and magnesium sulfate(MgSO47H2O) in water to make 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 D1126. The hardness of th

32、e test water will be 10.0 60.5 meq/L. Use the determined hardness 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 D1126. This reagent isused only in prepara

33、tion 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 throughout the test.11

34、.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 theprocedure

35、.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 tube to a heigh

36、t 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, inmillilitres

37、, 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 flow rate of

38、 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 D1126. Record thevolume of test water used.11.6

39、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 volume determina

40、tion 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 material shall be tha

41、t 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, usingTABLE 1 Amou

42、nt of Brine Regenerant Required for Use in Test Method AType of ExchangeMaterialBrine Regenerant, Rate of Flow, Contact Time,RegenerationLevelg/L mL brine/min/mL of Exchanger min lb/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 80.1

43、Carbonaceous 50 0.067 15 3.15 50.5D1782 173the 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 indicat

44、or and 0.5 mL of sodium ethylendiaminetetraacetate 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.

45、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 volume. Continuewith a regeneration and rinse (see 11.8), and end with a servicerun (see 11.5). Repeat the cycle until each of

46、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 milliequivalentsper millilitre, of the ion exchange material as:capacity, meq/mL 5 A 3B!/Swhere:A = hardness of test water, meq/L,B

47、= 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 materials,it is the average volume of the material in the exhaustedform as determined in 11.6.1

48、2.2 Calculate the operating capacity, in kilograins of cal-cium carbonate per cubic foot as follows:capacity, kilograins of CaCO3/ft35 C 321.8where:C = capacity in milliequivalents per millilitre of ion-exchange material (see 12.1).13. Report13.1 Report the capacity of the tested material as theaver

49、age of three successive service runs that agree within65 % of their average capacity.14. Precision and Bias414.1 PrecisionPrecision was determined from the resultsof the analyses 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