1、Designation:D208706(Reapproved 2012)Standard Test Method forIron in Formaldehyde Solutions1This standard is issued under the fixed designation D2087;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number i
2、n parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method covers the determination of the totaliron content of formaldehyde solutions.1.2 For purposes of determining conformance of an ob-
3、served or a calculated value using this test method to relevantspecifications,test result(s)shall be rounded off“to the nearestunit”in the last right-hand digit used in expressing thespecification limit,in accordance with the rounding-off methodof Practice E29.1.3 The values stated in SI units are t
4、o be regarded asstandard.No other units of measurement are included in thisstandard.1.4 For hazard information and guidance,see the suppliersMaterial Safety Data Sheet.1.5 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of th
5、e 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:2D1193 Specification for Reagent WaterE29 Practice for Using Significant Digits in Test Data toDetermine Conf
6、ormance with Specifications3.Summary of Test Method3.1 The specimen is evaporated and ashed;the iron,reducedto the divalent state by the addition of hydroxylamine hydro-chloride,is reacted with o-phenanthroline to develop a colorthat is measured at 510 nm.4.Significance and Use4.1 This test method p
7、rovides a measurement of iron con-tent of formaldehyde solutions.The results of these measure-ments can be used for specification acceptance.5.Apparatus5.1 Spectrophotometer,capable of measuring light absorp-tion at 510 nm.5.2 Absorption Cells,minimum light path,10 mm.5.3 Evaporating Dishes,90-mm di
8、ameter,high-silica glass.6.Reagents and Materials6.1 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 such
9、 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.6.2 Purity of WaterUnless otherwise indicated,referencesto water shall be understood to mean rea
10、gent water as definedby Type IV of Specification D1193.6.3 Ammonium Acetate Solution(100 g/L)Dissolve 100 gof ammonium acetate(NH4C2H3O2)in 100 mL of water.Add200 mL of acetic acid(CH3COOH),dilute to 1 L with water,and mix.6.4 Ammonium Hydroxide(1+1)Mix equal volumes ofconcentrated ammonium hydroxid
11、e(NH4OH,sp gr 0.90)andwater.6.5 Congo Red Paper.6.6 Hydrochloric Acid(1+1)Mix equal volumes of con-centrated hydrochloric acid(HCl,sp gr 1.19)and water.1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings,Materials,and Applications and is the direct responsi
12、bility ofSubcommittee D01.35 on Solvents,Plasticizers,and Chemical Intermediates.Current edition approved June 1,2012.Published July 2012.Originally approvedin 1962.Last previous edition approved in 2006 as D2087 06.DOI:10.1520/D2087-06R12.2For referenced ASTM standards,visit the ASTM website,www.as
13、tm.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.3Reagent Chemicals,American Chemical Society Specifications,AmericanChemical Society,Washington,DC.For suggestions on the test
14、ing 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.Pharmacopeial Convention,Inc.(USPC),Rockville,MD.*A Summary of Changes section appears at the end of this st
15、andardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.7 Hydroxylamine Hydrochloride Solution(100 g/L)Dissolve 10 g of hydroxylamine hydrochloride(NH2OHHCl)in water and dilute to 100 mL.6.8 Iron,Standard Solution(1 mL=0.05 mg Fe)Dissolve
16、0.3510gofferrousammoniumsulfate(FeSO4(NH4)2SO46H2O)in 50 mL of water and 20 mL of concen-trated sulfuric acid(H2SO4,sp gr 1.84).Dilute with water to 1L in a volumetric flask and mix.6.9 o-Phenanthroline Solution(1 g/L)Dissolve 0.1 g ofo-phenanthroline in 10 mL of iron-free ethyl alcohol4anddilute to 100 mL with water.7.Calibration7.1 Prepare a series of standards by adding the reagentsdescribed in 6.3 to 0.2,0.5,1.0,2.0,3.0,4.0,and 5.0-mL ofstandard iron solution in 100-mL volumetric flasks,and
