ASTM_D_3861_-_91_2011.pdf

Designation:D386191(Reapproved 2011)Standard Test Method forQuantity of Water-Extractable Matter in Membrane Filters1This standard is issued under the fixed designation D3861;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 gravimetric determinationof the water-extractable material present in membrane filtersand is applicable over the complete concentration range ofextractables.1.2 The analyst should be aware that adequate collaborativedata for precision and bias statements as required by PracticeD2777 is not provided.See Section 11 for details.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 the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1129 Terminology Relating to WaterD1193 Specification for Reagent WaterD2777 Practice for Determination of Precision and Bias ofApplicable Test Methods of Committee D19 on Water3.Terminology3.1 DefinitionsFor definitions of terms used in this testmethod,refer to Terminology D1129.4.Summary of Test Method4.1 The quantity of water-soluble extractables present inmembrane filters is determined by immersing the preweighedmembrane in boiling reagent grade water for an extended time,then drying and reweighing the membrane.A control mem-brane is employed to eliminate weighing errors caused bybalance changes or changing moisture content of the mem-brane in the weighing procedures.Weight changes of thecontrol membrane are applied as a correction factor to theweight change of the test membrane filters.5.Significance and Use5.1 The presence of water-soluble extractables in membranefilters can create errors in test procedures employing membranefilters.However,these errors can be eliminated or significantlyreduced if the quantity of water-soluble extractables of thespecific membrane is previously determined.Certain mem-brane filter uses require specifications of maximum water-soluble extractable levels.This test method is intended to be arapid test to determine the loss of water-soluble compoundssuch as plasticizers or wetting agents from filtration mem-branes.This test method is not designed to predetermine theperformance of a filter,but is significant in determining thepercent extractables of membranes from different sources andlot variations from a single source.6.Apparatus6.1 Beaker,borosilicate glass,300-mL capacity.6.2 Forceps,stainless steel,unserrated tips.6.3 Desiccator.6.4 Drying Oven,with thermostatic control.6.5 Analytical Balance,sensitivity 0.01 mg.6.6 a-Emitting Polonium Source3(to discharge static chargein balance).6.7 Humidity-Controlled Room or Hood,for balance.6.8 Evaporating Dishes,glass,having sides or other meansto keep test filters on the dish while drying.7.Reagents and Materials7.1 Purity of Water Unless otherwise indicated,referencesto water shall be understood to mean Type III reagent waterconforming to Specification D1193.7.2 Membrane Filters,47-mm diameter(same type as thoseunder test).8.Preparation of Apparatus and Materials8.1 Preparation of Samples and Apparatus:1This 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 May 1,2011.Published May 2011.Originallyapproved in 1979.Last previous edition approved in 2003 as D3861 91(2003).DOI:10.1520/D3861-91R11.2For 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.3The“Staticmaster,”available from Nuclear Products Inc.,El Monte,CA,hasbeen found suitable for this purpose.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 8.1.1 Select 47-mm diameter sample(Note 1)membranefilters for the test,and label with water-resistant ink.NOTE1Square or rectangular membrane of equivalent area(17.4 cm2)may be used.8.1.2 To provide a“control filter,”select and label oneadditional 47-mm membrane filter of the same type as thosebeing tested.Take the control filter through all the drying andweighing steps,but do not extract.8.1.3 Set drying oven at 70C.9.Procedure9.1 Heat the test and control filters in the oven at 70C for15 min.9.1.1 Remove filters from the oven and place them in thedesiccator for at least 30 min at room temperature.9.1.2 Remove filters from desiccator and place them inbalance room atmosphere for 10 to 15 min.9.1.3 In a humidity-controlled bala