1、Designation:E 1148 02Standard Test Method forMeasurements of Aqueous Solubility1This standard is issued under the fixed designation E 1148;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 parenthe
2、ses indicates the year of last reapproval.Asuperscript epsilon(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers procedures for measurement ofthe solubility of organic compounds in water.Three proceduresare described which will work over a varie
3、ty of solubilityranges.These procedures are not appropriate for compoundsthat react with water or air at ambient conditions.1.2 The procedure chosen will depend on the estimatedsolubility of the compound.This may be obtained fromliterature values(see Refs 1,2,3)2by correlation with otherparameters(4
4、)or by analogy with the solubility of similarcompounds.1.3 This standard does not purport to address all of thesafety problems,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
5、 regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:D 1193 Specification for Reagent Water33.Terminology Definition3.1 solubility in waterthe extent to which a substancemixes with pure water to form a molecular homogeneoussystem at a given temperature.For the case of a sing
6、le puresubstance,solubility in water is an equilibrium state(5).Theparticular method used will define what one means by aqueoussolubility.4.Significance and Use4.1 The solubility of organics is a basic physical parameterneeded for the prediction of the fate of a chemical in theenvironment(6).4.1.1 T
7、he ionic strength and organic content of naturalwaters may cause an apparent decrease or increase from thevalue obtained in pure water.Data on this can be obtained inthe laboratory by modifying the reagent water to simulatenatural waters.5.Reagents5.1 Reagent grade or better chemicals shall be used
8、in allprocedures.It is intended that all reagents shall conform to thespecifications of the Committee on Analytical Reagents of theAmerican Chemical Society,4where such specifications areavailable.Lower grades may be used provided it is firstascertained that the impurities do not interfere with thep
9、rocedure.5.2 Purity of WaterReagent water shall conform to Speci-fication D 1193 for Type II grade water.6.Sampling6.1 Take at least 3 samples at appropriate intervals andanalyze to demonstrate that equilibrium has been reached.Equilibrium is defined as identical concentrations within theprecision o
10、f the analytical method.7.Procedure7.1 Determine solubilities at 25C5and any other tempera-ture as appropriate.Measure those chemicals that reversiblyionize or protonate at a pH of pKa+2 pH units and a pH ofpKa 2 pH units for pKa values which fall in the range of 5 to9(7),as well as nonionizable org
11、anics.Adjust the system withHCl or NaOH as appropriate.A weak buffer(for example,0.001 M)may be useful to stabilize the pH,depending on thesolubility of the test substance.Report the solubility as mg/L atthe experimental temperature and pH.For lower solubilities itis suggested,in order to minimize l
12、osses due to adsorption,thatall transfer apparatus should be prerinsed with portions of thesolution.7.1.1 The effect of ionic strength or organic matter or bothmay be studied by adding appropriate substances in the reagentwater.7.2 Method A1Solubilities of 1 mg/L or Greater:1This test method is unde
13、r the jurisdiction of ASTM Committee E47 onBiological Effects and Environmental Fateand is the direct responsibility ofSubcommittee E47.06on Environmental Fate of Chemical Substances.Current edition approved January 10,2002.Published March 2002.Originallypublished as E114887.Last previous edition E1
14、14887(1993)e1.2The boldface numbers in parentheses refer to the list of references at the end ofthis test method.3Annual Book of ASTM Standards,Vol 11.01.4“Reagent Chemicals,American Chemical Society Specifications,”Am.Chemi-cal Soc.,Washington,DC.For suggestions on the testing of reagents not liste
15、d bytheAmerican Chemical Society,see“Reagent Chemicals and Standards,”by JosephRosin,D.Van Nostrand Co.,Inc.,New York,NY,and the“United StatesPharmacopeia.”5International Union of Pure and Applied Chemistry(IUPAC),“Commission onThermodynamics and Thermochemistry,”AGuide to Procedures for the Publica
16、tionof Thermodynamic Data,Pure and Applied Chemistry,Vol 29,No.397,1972.1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.7.2.1 Obtain equilibrium by gently shaking or stirring ap-propriately an excess of the compound in a flask of reagentwater.Equilibrium times will depend upon the physical prop-erties of the compound.Obtain the solubility by periodicallydetermining the concentration of the solute over a length oftime,at least 2 h betw
