1、Designation: D820 93 (Reapproved 2016)Standard Test Methods forChemical Analysis of Soaps Containing SyntheticDetergents1This standard is issued under the fixed designation D820; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the
2、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 These test methods cover procedures for the chemicalanalysis of soaps containing synthetic detergents.1.2 The
3、analytical procedures appear in the following order:SectionsMoisture and Other Matter Volatile at 105C (Oven Method) 5 and 6Free Alkali or Free Acid 7 and 8Anhydrous, Salt-Free, Soda Soap 912Alcohol-Soluble Matter 13 and 14Matter Insoluble in Water 15 and 15Total Alkalinity of Matter Insoluble in Al
4、cohol (Alkaline Salts) 16 and 17Sodium Silicate 1820Phosphates 2128Phosphate (Colorimetric Method Using Molybdenum Blue) 2934Unsaponified and Unsaponifiable Matter 3539Free Fatty Matter 40Chlorides in Alcohol-Soluble Matter 4143Rosin (McNicoll Method) 4447Synthetic Detergent (by Difference) 48Neutra
5、l, Inorganic Salts 491.3 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.4 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 stand
6、ard 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 Referenced Documents2.1 ASTM Standards:2D216 Method of Test for Distillation of Natural Gasoline(Withdrawn 1988)3D459 Terminology Relating to Soaps and Other Detergent
7、sD875 Method for Calculating of Olefins and Aromatics inPetroleum Distillates from Bromine Number and AcidAbsorption (Withdrawn 1984)3D1193 Specification for Reagent WaterD1768 Test Method for Sodium Alkylbenzene Sulfonate inSynthetic Detergents by Ultraviolet AbsorptionD2357 for Qualitative Classif
8、ication of Surfactants by Infra-red AbsorptionD2358 Test Method for Separation ofActive Ingredient fromSurfactant and Syndet CompositionsD3049 Test Method for Synthetic Anionic Ingredient byCationic Titration3. Terminology3.1 Definitions:3.2 The term synthetic detergent in these test methods isdefin
9、ed in accordance with Terminology D459, as follows:3.3 synthetic detergenta detergent produced by chemicalsynthesis and comprising an organic composition other thansoap.3.4 For definitions of other terms used in these test methods,refer to Terminology D459.4. Purity of Reagents and Materials4.1 Puri
10、ty 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 specifications are available.4Other grades may beused,
11、 provided it is first ascertained that the reagent is of1These test methods are under the jurisdiction of ASTM Committee D12 onSoaps and Other Detergentsand are the direct responsibility of SubcommitteeD12.12 on Analysis and Specifications of Soaps, Synthetics, Detergents and theirComponents.Current
12、 edition approved July 1, 2016. Published August 2016. Originallyapproved in 1945. Last previous edition approved in 2009 as D820 93(2009).DOI: 10.1520/D0820-93R16.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Boo
13、k of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For sugge
14、stions on the testing 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.Copyright ASTM International,
15、100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1sufficiently high purity to permit its use without lessening theaccuracy of the determination.4.2 Unless otherwise indicated, references to water shall beunderstood to mean reagent water conforming to SpecificationD1
16、193.MOISTURE AND OTHER MATTER VOLATILE AT105C (OVEN METHOD)5. Apparatus5.1 DishA porcelain or glass dish about 6 to 8 cm indiameter and about 2 to 4 cm in depth will be required.6. Procedure6.1 Weigh 5 6 0.01 g of the sample in the dish, and dry toconstant weight in an air oven at a temperature of 1
17、05 6 2C.Constant weight is attained when heating for successive 1-hperiods shows a loss (or gain) of not more than 0.1 %.NOTE 1Because of its established use in the trade, the term weight isemployed in these methods in place of the technically correct term mass.FREE ALKALI OR FREE ACID7. Reagents7.1
18、 Ethyl Alcohol, Neutral (95 %) Freshly boiled, reagentgrade, ethyl alcohol, 95 % or higher, neutral tophenolphthalein, and containing only volatile denaturants, 95mL,5plus 5 mL of water.7.2 Phenolphthalein Indicator Solution (10 g/litre)Dissolve1gofphenolphthalein in 50 mL of neutral ethylalcohol (9
19、5 %) and mix with 50 mL of water (see 7.1).8. Procedure8.1 Weigh 5 to 10 6 0.01 g of the sample into a 300-mLErlenmeyer flask.Add 200 mL of neutral ethyl alcohol (95 %).Equip the flask with an air-cooled reflux condenser, and digestthe sample on a steam bath until the soap is dissolved (see Note2).
20、Remove the condenser, add 0.5 mL of the phenolphthaleinindicator solution, and titrate immediately with standard acidor alkali. Calculate as NaOH, if alkaline, or as oleic acid, ifacid.NOTE 2In the analysis of soaps known to contain little or no alkalinesalts, it is unnecessary to filter the hot alc
21、oholic soap solution. However,the filtration should be carried out in all cases where alkaline salts such assilicates, phosphates, borates, and similar salts are present, since these areknown to affect the free alkali determination. Free alkali figures in soap orsurfactant mixtures containing borax
22、are unreliable, due to solubility ofborax in hot alcohol.ANHYDROUS, SALT-FREE, SODA SOAP9. Apparatus9.1 Extraction Cylinder, 250-mL, graduated, glass-stoppered, about 39 mm (112 in.) in diameter and about 35.5cm (14 in.) in length.9.2 Stokes Flask, 100-mL, round-bottom (with the bottomblown out), se
23、aled onto a 150-mL Erlenmeyer flask.Adiagramof the Stokes flask is shown in Fig. 1.9.3 Siphon, consisting of a two-hole rubber stopper fittedwith small-diameter glass tubing as shown in Fig. 2.10. Reagents10.1 Ethyl Alcohol, Neutral (95 %) Freshly boiled, re-agent grade, ethyl alcohol, 95 % or highe
24、r, neutral tophenolphthalein, and containing only volatile denaturants, 95mL,5plus 5 mL of water.10.2 Methyl Orange Indicator Solution (1 g/litre)Dissolve0.1 g of methyl orange in water and dilute to 100 mL.10.3 Petroleum EtherThe solvent used shall be of thepentane type, containing a minimum amount
25、 of isopentane,isohexane, and hexane, and boiling in the range 35 to 60C.6Distillation test:AInitial boiling point 35 to 38CDry flask end point 52 to 60CDistilling under 54C, min 95 %Distilling under 40C, max 60 %Specific gravity at 15.5/15.5C (60/60F) 0.630 to 0.660Color water-whiteDoctor test swee
26、tEvaporation residue, 100 mL, max 0.0011 gCopper-strip corrosion testBnoncorrosiveUnsaturated compoundsCtrace only permittedResidue in distilling flask neutral to methyl orangeBlotter-strip odor testDodorless within 12 minAromatic compoundsEno nitrobenzene odorSaponification value less than 1.0 mg K
27、OH/100 mLAThe distillation test shall be made in accordance with Method D216. As a checkon the evaporation residue, 250 mL of the petroleum ether and 0.25 g of stearin orother hard fat (previously brought to constant weight by heating) when dried as inthe actual determination (10.4) shall not show a
28、n increase in weight exceeding0.003 g.BThe copper-strip corrosion test shall be made by inserting a small polishedcopper strip into the petroleum ether in the distilling flask. There should be noappreciable darkening of the copper.CUnsaturated compounds shall be determined by the method for determin
29、ingolefins described in Method D875.5Fischer Scientific A962, or its equivalent, is suitable for this purpose.6J. T. Baker Analyzed Reagent 9268, or its equivalent, is suitable for thispurpose.FIG. 1 Stokes FlaskD820 93 (2016)2DOdor test: Immerse 1 in. of a strip of white unglazed blotting paper, ap
30、proxi-mately 1 by 4 by 0.166 in. in size, in the petroleum ether for 30 s, remove the strip,and allow to dry at room temperature in still air for 12 min.EAromatic compounds: Add 5 drops of petroleum ether to 40 drops of sulfuric acid(H2SO4, sp gr 1.84) and 10 drops of nitric acid (HNO3, sp gr 1.42)
31、in a test tube,warm for 10 min, allow to cool for 30 min, transfer to a shallow dish, and dilute withwater.10.4 Phenolphthalein Indicator Solution (10 g/litre)Dissolve1gofphenolphthalein in 50 mL of neutral ethylalcohol (95 %) and then mix with 50 mL of water (see 10.1).10.5 Sodium Hydroxide, Standa
32、rd Solution (0.1 N)Prepare and standardize a 0.1 N sodium hydroxide (NaOH)solution.10.6 Sodium Sulfate (Na2SO4), anhydrous.10.7 Sulfuric Acid, Standard (0.5 N)Prepare and standard-ize a 0.5 N sulfuric acid (H2SO4) solution.10.8 Sulfuric Acid (sp gr 1.84)Concentrated sulfuric acid(H2SO4).10.9 Sulfur
33、Acid (1+1)Gradually pour 10 g of concen-trated sulfuric acid (H2SO4) (sp gr 1.84) onto 10 g of crackedice made from distilled water, gently swirling the mixingvessel; or gradually pour the acid down the sides of the mixingvessel into an equal weight of water, swirling gently, whilesubmersing the ves
34、sel in an ice bath.11. Procedure11.1 Weigh 2 6 0.001 g of the sample into a tared 250-mLbeaker.Add 25 mLof water and 25 mLof neutral ethyl alcohol(95 %), and warm on the steam bath until solution is complete.Cool, add 5 drops of methyl orange indicator solution, andtitrate with 0.5 N H2SO4to a pink
35、color. Add 5 mL of H2SO4(1+1) in excess.11.2 Transfer the contents of the beaker to a 250-mLextraction cylinder or a Stokes flask, equipped with a siphon.Wash the beaker alternately with equal parts of hot water andhot ethyl alcohol (95 %), adding the washings to the extractioncylinder or Stokes fla
36、sk. Keep the total volume for extractionunder 160 mL in the extraction cylinder, or within theconstricted portion of the Stokes flask. Wash the beaker with asmall amount of petroleum ether to remove any traces of fattyacids and fatty matter and add to the extraction cylinder orStokes flask. Cool the
37、 cylinder or flask under tap water to atemperature not to exceed 25C.Add 50 mLof petroleum etherand allow to stand for12 h without shaking. Remove thegreater part of the fatty acids by drawing off the petroleumether layer as closely as possible, by means of a glass siphon,into a 500-mL separatory fu
38、nnel. Repeat the extractions fivemore times with petroleum ether, using 50-mL portions, andshaking the cylinder thoroughly each time.NOTE 3If an emulsion appears at this point, it may be broken by theaddition of 10 g of anhydrous Na2SO4.11.3 Combine the petroleum ether extracts and wash withsmall po
39、rtions of distilled water until the water washings are nolonger acid to methyl orange indicator solution. Dry thecombined, washed, petroleum ether extracts with anhydrousNa2SO4, and filter through paper into the original tared 250-mLbeaker. Wash the separatory funnel with two small portions ofpetrol
40、eum ether, filtering and adding the washings to thebeaker.11.4 Evaporate the petroleum ether extract on the steambath until about 1 mL remains. Then swirl manually until thelast trace of solvent evaporates and the odor of petroleum etheris no longer perceptible. Cool in a desiccator and weigh as tot
41、alfatty matter, which is defined as fatty and rosin acids plusunsaponified and unsaponifiable fatty matter.11.5 Dissolve the total fatty matter in 50 mLof neutral ethylalcohol (95 % v) with warming.Add phenolphthalein indicatorand titrate with 0.1 NaOH solution to a pink end point.12. Calculations12
42、.1 Calculate the percentage of anhydrous, salt-free, sodasoap as follows:A 5 G 2 F (1)G 5 VN 30.022!1E!/W# 3100where:A = weight percent of anhydrous, salt-free, soda soap,G = weight percent of soda soap plus unsaponified andunsaponifiable fatty matter,F = weight percent of unsaponified and unsaponif
43、iablefatty matter (Section 39),V = millilitres of NaOH solution used in titration (11.5),N = normality of NaOH solution,E = grams of extract (11.4), andW = grams of sample (11.1), and0.022 = net gain in milliequivalent weight from the conver-sion of the fatty acid to the sodium salt by replace-ment
44、of a proton with a sodium ion.ALCOHOL-SOLUBLE MATTER13. Reagents13.1 Ethyl Alcohol, Neutral (95 %) Freshly boiled, re-agent grade, ethyl alcohol, 95 % or higher, neutral tophenolphthalein, and containing only volatile denaturants, 95mL5plus 5 mL of water.13.2 Ethyl Alcohol, Neutral (absolute) Freshl
45、y boiledabsolute ethyl alcohol, neutral to phenolphthalein.5FIG. 2 SiphonD820 93 (2016)314. Procedure14.1 Weigh 2 6 0.001 g of the sample into a 250-mLbeaker. Add 100 mL of neutral ethyl alcohol (95 %), cover thebeaker, and heat on the steam bath with frequent stirring andmaceration of the sample un
46、til completely disintegrated. Letsettle and filter the supernatant liquid through a tared Goochcrucible with a glass wool pad, with suction into a tared300-mL Erlenmeyer flask, retaining as much of the residue aspossible in the beaker. Repeat this extraction three times with25-mL portions of hot neu
47、tral ethyl alcohol (95 %), each timeretaining as much of the residue as possible in the beaker.Finally, evaporate any remaining alcohol and dissolve theresidue in the smallest possible quantity of hot water (5 mL ifsufficient). Reprecipitate the alcohol-insoluble matter byslowly adding, while stirri
48、ng vigorously, 50 mLof neutral ethylalcohol (absolute).NOTE 4Solution and reprecipitation of alcohol-insoluble matter isnecessary for complete separation from alcohol-soluble matter.14.2 Heat the solution to boiling on the steam bath, filter,and transfer the precipitate quantitatively to the Goochcr
49、ucible, washing several times with neutral ethyl alcohol(95 %). Evaporate the combined filtrate and washings in theErlenmeyer flask on the steam bath, and then dry to constantweight at 105 6 2C. Calculate total alcohol-soluble matter.14.3 Reserve the flask and contents for the determination offree fatty matter (Section 37). Reserve the Gooch crucible andcontents, without drying, for the determination of matterinsoluble in water (Section 15) and total alkalinity of matterinsoluble in alcohol (alkaline salts) (Section 17).MATTER INSOLUBLE I
