1、Designation: D3375 16Standard Test Method forColumn Capacity of Particulate Mixed Bed IonExchange Materials1This standard is issued under the fixed designation D3375; 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 This test method covers the determination of the perfor-mance of particulate mixed bed ion exchange materials in theregene
3、rated form when used for deionization. It is intended foruse in testing unused mixed bed materials and samples ofregenerated mixed beds from operating units.1.2 The values stated in SI units are to be regarded asstandard. The values given in parentheses are mathematicalconversions to inch-pound unit
4、s 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 user of this standard to establish appro-priate safety and health practices and determine
5、 the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1125 Test Methods for Electrical Conductivity and Resis-tivity of WaterD1129 Terminology Relating to WaterD1193 Specification for Reagent WaterD1293 Test Methods for pH of WaterD1782 Test Methods f
6、or Operating Performance of Particu-late Cation-Exchange MaterialsD2687 Practices for Sampling Particulate Ion-Exchange Ma-terials3. Terminology3.1 DefinitionsFor definitions of terms related to water,refer to Terminology D1129.4. Summary of Test Method4.1 This test method consists of exhausting a c
7、olumn ofregenerated mixed bed ion exchange material to a specific endpoint with an influent solution of known composition andvolume.5. Significance and Use5.1 This test method can be used to evaluate unused mixedbed ion exchange materials for conformance to specifications.When a representative sampl
8、e of the mixed bed can beobtained from an operating unit, this test method can be usedto evaluate the regeneration efficiency by comparison with thesame data obtained with new material from the same manu-factured lots, or retained samples of the in-place products.5.2 This test method provides for th
9、e calculation of capacityin terms of the volume of water treated to a conductivity endpoint.5.3 The test method as written assumes that the cationexchange material has been regenerated to the hydrogen formwith acid and the anion exchange material has been regener-ated with alkali to the hydroxide or
10、 free-base form. In certainapplications a cation exchange material in the potassium,ammonium, or other monovalent form may be encountered.Such materials may be tested following this procedure usingTest Water A (Test Methods D1782) as the influent andsubstituting the hardness end point (Test Methods
11、D1782) forthe end points prescribed herein.5.4 In most cases the product tested will be properly mixedand will contain the correct proportions of anion and cationexchange materials. However, if the pH as well as theconductivity of the effluent is measured, the test method willindicate which of the c
12、omponents is present in excess; an acideffluent at breakthrough indicating an excess of regeneratedcation exchange groups and an alkaline effluent an excess ofregenerated anion exchange groups. In such cases the volumesof the two components obtained in the final backwash willindicate whether this im
13、balance arises from improper regen-eration or from an improper ratio of the two components. Itshould be noted, however, that not all units are charged with abalanced ratio of anion-exchanging and cation-exchanging1This test method is under the jurisdiction of ASTM Committee D19 on Waterand is the di
14、rect responsibility of Subcommittee D19.08 on Membranes and IonExchange Materials.Current edition approved July 1, 2016. Published July 2016. Originally approvedin 1975. Last previous edition approved in 2007 as D3375 95a (2007). DOI:10.1520/D3375-16.2For referenced ASTM standards, visit the ASTM we
15、bsite, 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 website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United Sta
16、tes1groups. Hence, wherever possible, a field sample should beevaluated in comparison with a retained sample of the originalcharge.5.5 This test method provides for the calculation of capacityon either a wet weight basis or a volume basis. Although suchmaterials are normally bought and sold in terms
17、 of cubic feet,they are actually packaged in wet pounds. Therefore, it is thecapacity on a wet weight basis that is directly correlatable tothe amount of material in a given shipment.5.6 Calculation of a volume capacity is based on theexhausted, separated volume of the components after back-washing
18、and resettling the bed. This volume is chosen becauseit is difficult, if not impossible, to pack a sample of regeneratedmixed bed material in a small-diameter column reproducibly.5.7 This test method may be used to test mixed bed resincartridges. In such cases the flow rate of test water and thefreq
19、uency of sampling must be varied to compensate for theapproximate volume of resin in the test sample. The test aswritten assumes a resin volume of approximately 330 mL.6. Apparatus6.1 Test Assembly (Fig. 1), consisting of the following:6.1.1 Column, transparent supported 2.5 6 0.25-cm (1 60.1-in.) i
20、nside diameter and approximately 150 cm (60 in.)long. The bottom of the column shall be closed and providedwith an outlet of about 6-mm inside diameter. Connectionsshall be provided at the top and the bottom for the admissionand removal of the exhausting solution as described in 7.4.Adequate means o
21、f regulating and measuring flow shall beprovided. Support for the sample shall be provided so that thedistance from the sample to the column outlet is at least 5 cm.Calibrate the column in such a manner that the volumereadings required by the test method can be made. Make allcalibration measurements
22、 at 25 6 5C.6.1.2 Sample Support, so designed that the distance from thesample to the column outlet is at least 5 cm. A suggestedsupporting bed utilizes quartz, gravel, glass beads, or othermaterial 1.5 to 3.5 mm in diameter, insoluble in the reagentsused, and retained on a corrosion-resistant scree
23、n.6.2 Measuring circuit and in-line conductivity cells asdescribed in Test Methods D1125. A continuous recorder isrecommended.6.3 pH Meter, with associated electrodes as described inTest Methods D1293. A continuous recorder is recommended.FIG. 1 Typical Arrangement of Apparatus for Performance Testi
24、ng of Ion Exchange MaterialsD3375 1627. Reagents7.1 Purity of ReagentsReagent grade chemicals shall beused in all 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,where suc
25、h 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.7.2 Purity of WaterAll reference to water in this testmethod shall be understood to mean Reage
26、nt Water Type I orII conforming to Specification D1193, with the additionalrequirement that the silica concentration is less than 0.1 mg/L.7.3 Ammonium Hydroxide Solution (1+19)Carefully pour50 mL of concentrated ammonium hydroxide (NH4OH, sp gr0.90) into 500 mL of water, stirring constantly. Cool t
27、o 25 65C and dilute to 1 L with water. Mix well.7.4 Ion Exchange Test Water D (10 meq/L)Prepare a testwater containing, in each litre, 0.585 g of oven-dried (105C)sodium chloride (NaCl). Approximately 25 L of this solutionare required for a single test.7.4.1 To standardize for chloride content, pipe
28、t three100-mL portions. Add one drop of methyl orange indicatorsolution and one drop of phenolphthalein indicator solution toeach and neutralize, if required, by dropwise addition ofHNO3(1+9) until the color changes from yellow to orangefollowed by dropwise addition of NH4OH (1+19) to restore theyel
29、low color. Pipet in 1 mL of K2CrO4solution (50 g/L) andtitrate each with standard 0.1 N AgNO3solution until the colorof the supernatant solution changes from yellow to red-orangeand persists for 30 s with vigorous swirling. Record theaverage number of millilitres ofAgNO3solution used to 60.02mL.7.4.
30、2 Calculate the strength of the solution in meq ofchloride as follows:Chloride, meq/L 5 V 3N 310 (1)where:V = millilitres of AgNO3solution required for titration, andN = normality of the AgNO3solution.The test solution used should have a concentration of 10 60.5 meq/L of chloride.NOTE 1Because of th
31、e large quantities of this reagent that arerequired, it is usually made up semi-quantitatively in large batches andthen standardized per the above procedure. If desired, it is acceptable toprepare this reagent quantitatively (as for a primary standard) and theneliminate the above standardization.7.5
32、 Methyl Orange Indicator Solution (1.0 g/L)Dissolve0.10 g of methyl orange in water and dilute to 100 mL withwater.7.6 Nitric Acid (1+9)Pour one volume of nitric acid(HNO3, sp gr 1.42) into nine volumes of water and mixthoroughly.7.7 Phenolphthalein Indicator Solution (10.0 g/L)Dissolve 1.0 g of phe
33、nolphthalein in 100 mL of 95 % ethanol.NOTE 2In most cases certain denatured alcohols such as speciallydenatured Formula Nos. 3A, 30, or 2B may be substituted for ethanol.7.8 Potassium Chromate Solution (50 g/L)Dissolve 5.0 gof potassium chromate (K2CrO4) in 50 mL of water. Dilute to100 mL with wate
34、r.7.9 Silver Nitrate Solution, Standard (0.10 N)Dry crys-talline silver nitrate (AgNO3) at 105C for 1 h and cool in adesiccator. Weigh out 17 6 0.05 g. Transfer to a 1-Lvolumetricflask with water. Dissolve in 500 mL of water and mixthoroughly. Dilute to 1 L with water at 25 6 5C. Mix well.Store the
35、solution in a tightly stoppered amber glass bottle.7.9.1 To standardize, dry approximately5gofreagentsodium chloride (NaCl) in a glass container at 105C for 2 h.Cool in a desiccator. Weigh accurately three 0.2500 60.0100-g portions of the dried NaCl and transfer to separate250-mL conical flasks. Add
36、 100 mL of water and swirl todissolve the NaCl. Pipet in 1 mL of K2CrO4solution (50 g/L)and titrate with the 0.1 N AgNO3solution with vigorousswirling until the color of the solution changes from yellow tored-orange and persists for 30 s.7.9.2 Calculate the normality of the AgNO3solution asfollows:N
37、 5 D/0.05845 3E (2)where:N = normality of the AgNO3solution,D = actual weight of NaCl used, andE = millilitres of AgNO3solution used.8. Sampling8.1 For sampling refer to Practices D2687.8.2 When sampling new mixed bed materials the drum-to-drum uniformity of the mixing is an important factor, partic
38、u-larly if the material is to be repackaged into small cartridges.Hence, if samples are taken from three or more separate drumsor bags of a given lot a composite sample is not prepared butone column is run from each container sampled. Where thesequence of filling is known such samples should include
39、 thefirst and the last container filled.9. Procedure9.1 Weigh 270 6 1 g of the moist, as received, mixed bedion exchange material, and record weight to the nearest 0.1 g.Introduce through the backwash line about 25 mm of water tothe column. Place about 25 mL of the sample in a large-stemmed plastic
40、funnel inserted in the top of the column. Washthe portion of sample into the column with a minimum ofwater. Repeat until all the sample is transferred into thecolumn. Care must be exercised that no stratification takesplace during the filling procedure. Maintain the water level inthe column about 10
41、 mm over the bed level to minimize airtrapping.3Reagent Chemicals, American Chemical Society Specifications, 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,
42、 Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmaceutical Convention, Inc. (USPC), Rockville,MD.D3375 1639.2 When all the mixed bed ion exchange material has beentransferred slowly introduce test water D at the top of thecolumn. Increase the flow rate to 100 mL/min
43、, adjusting therate as required with a flow regulator in the effluent line.9.3 Measure and record the effluent conductivity accordingto Test Methods D1125 every 2 L. Continue until the 1.0 S/cmvalue is passed, then record readings for each 500 mL ofeffluent until two successive readings greater than
44、 50 S/cm(20 000 cm) are obtained.9.4 When the effluent conductivity exceeds 1.0 S/cm (1Mcm), measure the pH of the effluent according to TestMethods D1293. Continue the pH measurements at the samefrequency as the conductivity measurements.9.5 When the conductivity exceeds 50 S/cm (20 000cm), stop th
45、e flow of test water and record the total volume(V) of test water used in litres.9.6 Open the backwash valves and backwash the bed withwater for 10 min at a flow rate sufficient to maintain a 50 %expansion of the bed. Stop the flow of water and allow the bedto settle. Drain at the rate of 100 mL/min
46、 until the water levelis 20 to 30 mm above the bed. Do not jar. Record the bedvolume in millilitres. Repeat the backwash and drain procedureuntil two successive readings of the resettled bed volume agreewithin 5 mL. Record the average volume as S mL.10. Calculation10.1 The operating capacity may be
47、calculated on either avolume or wet weight basis using a conductivity end point.10.2 Calculate the operating capacity to the conductivityend point on a volume basis as follows:Capacity, meq/mL 5 C 3V/S (3)where:C = total electrolytes in test water D expressed in mil-liequivalents per litre as determ
48、ined in 7.4.2,V = volume of test water used, litres, measured in 9.5, andS = volume of sample measured in 9.6.This capacity may be converted to kilograins per cubic footas CaCO3by multiplying by 21.8.10.3 Calculate the operating capacity to the conductivityend point on a wet weight basis as follows:
49、Capacity, meq/g wet 5 C 3V/270 (4)where C and V are defined as in 10.2.NOTE 3Other end points may be agreed upon. When this is done thespecies and level selected should be specified with the results.11. Report11.1 The report of results of this test method should includenot only the capacity as calculated above but the end pointused. For certification purposes the averaging of results fromthree separate samples is customary. However, when samplesfrom individual drums are analyzed the individual results aswell as the average should be reported.12. Precis
