ASTM_D_3375_-_95a_2007.pdf

Designation:D337595a(Reapproved 2007)Standard 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 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 theregenerated 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 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 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 for Operating Performance of Particu-late Cation-Exchange MaterialsD2687 Practices for Sampling Particulate Ion-Exchange Ma-terialsD2777 Practice for Determination of Precision and Bias ofApplicable Test Methods of Committee D19 on Water3.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 column 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 sample 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 the 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 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 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 components 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 imbalance 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 a1This test method is under the jurisdiction of ASTM Committee D19 on Waterand is the direct responsibility of Subcommittee D19.08 on Membranes and IonExchange Materials.Current edition approved Dec.1,2007.Published January 2008.Originallyapproved in 1975.Last previous edition approved in 2001 as D3375 95a(2001).DOI:10.1520/D3375-95AR07.2For 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 website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 balanced ratio of anion-exchanging and cation-exchanginggroups.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 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 and resettling the bed.This volume is chose