1、Designation: D 5547 95 (Reapproved 2003)Standard Test Method forClay and Zeolite in Powdered Laundry Detergents by AtomicAbsorption1This standard is issued under the fixed designation D 5547; the number immediately following the designation indicates the year oforiginal adoption or, in the case of r
2、evision, the year of last revision. A number in parentheses 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 atomic absorption tests appli-cable to powdered laundry detergents conta
3、ining clay andzeolite.21.2 The values stated in SI units are to be regarded as thestandard.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 practi
4、ces and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:E 180 Practice for Determining the Precision of ASTMMethods for Analysis and Testing of Industrial Chemicals33. Summary of Test Method3.1 The test sample is fused with lithium metabo
5、rate,dissolved in acid, its silicon and aluminum content measuredby atomic absorption, and the silicon/aluminum (Si/Al) ratiocalculated. The clay and zeolite content of the test sample iscalculated from the Si/Al ratio of the test sample and the Si/Alratio of the clay and zeolite expected in the tes
6、t sample.4. Interferences4.1 Materials other than clay and zeolite that contain siliconor aluminum, or both, will interfere.5. Principle5.1 Clay and zeolite contain silicon and aluminum at differ-ent relative levels.4The silicon/aluminum ratio is then ameasure of the relative level of clay and zeoli
7、te in detergentpowders. That is, detergent powders with a Si/Al ratio match-ing clay or zeolite contain only clay or zeolite, respectively.Detergent powders with Si/Al ratio falling between the Si/Alratio of clay and zeolite contain both clay and zeolite.5.2 This test method is based on the linear r
8、elationshipbetween the relative composition (or ratio) of clay/zeolite indetergent powders and the Si/Al ratio of such detergents.5.3 A calibration equation is derivable, therefore, from justtwo experimental points: the Si/Al ratio of the zeolite standard(100 zeolite, 0 % clay) and the Si/Al ratio o
9、f the clay standard(0 % zeolite, 100 % clay).6. Apparatus6.1 Suitable Atomic Absorption Spectrophotometers, fittedwith a nitrous oxide-acetylene burner and aluminum andsilicon hollow cathode source lamps.6.2 Nitrous Oxide and Acetylene Tanks, with suitable regu-lators.6.3 Muffle Furnace, capable of
10、reaching 1000C.6.4 Analytical Balance.6.5 Fisher Burner or Equivalent.6.6 20-mL or Larger Platinum Crucibles.6.7 Platinum-tip Tongs.6.8 25-mL Buret.6.9 100-mL and 200-mL Polypropylene Volumetric Flasks.6.10 10-mL and 25-mL Graduated Cylinders.6.11 150-mL Plastic Beakers.6.12 Magnetic Stirrer and Mag
11、netic Stirring Bars.6.13 Blender, such as Waring5or Osterizer6or an industriallab model, or a mortar and pestle, if a blender is not available.7. Reagents7.1 Purity of ReagentsReagents grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents conform to t
12、he specifications of the Committee onAnalytical Reagents of the American Chemical Society, where1This test method is under the jurisdiction of ASTM Committee D12 on Soapsand Other Detergents and is the direct responsibility of Subcommittee D12.12 onAnalysis of Soaps and Synthetic Detergents.Current
13、edition approved April 15, 1995. Published June 1995. Originallypublished as D 5547 94. Last previous edition D 5547 94.2Silicon and aluminum measurements are by atomic absorption in this testmethod. ICP can be used to make such measurements as well.3Annual Book of ASTM Standards, Vol 15.05.4The Si/
14、Al ratio is usually about 1 in zeolites and about 3 in clays.5Waring blenders are available commercially.6Osterizer blenders are widely available commercially.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.such specifications are av
15、ailable.7Other grades may be used,provided it is first ascertained that the reagent is of sufficientlyhigh purity to permit its use without lessening the accuracy ofthe determination.7.2 Purity of WaterUnless otherwise indicated, referenceto water shall be understood to mean distilled water or water
16、 ofequal purity.7.3 Aluminum Standard, 1000 g Al/mL8or equivalent.7.4 Silicon Standard, 1000 g Si/mL.87.5 Potassium Chloride, Baker-analyzed reagent or equiva-lent.7.6 Potassium Chloride Solution (1 %)Dissolve1gofpotassium chloride in 100 mL of distilled water. Mix well andstore in plastic container
17、.7.7 Concentrated Hydrochloric Acid, Baker-analyzed re-agent or equivalent.7.8 Hydrochloric Acid Solution (1 + 1)Mix equal parts ofconcentrated HCl and distilled water by volume. Mix well andstore in plastic container.7.9 Potassium Iodide, Baker-analyzed reagent or equiva-lent.7.10 Lithium Metaborat
18、e SPEX Grade, Special for Fu-sions9.7.11 Zeolite StandardThe same material expected in thetest sample, to be used as standard.7.12 Clay StandardThe same material expected in the testsample, to be used as standard.8. Instrumental Conditions8.1 Following the instrument manufacturers instructions,set u
19、p the atomic absorption instrument as follows:To measure Aluminum To measure SiliconWavelength, nm 309.3 251.6Range UV UVSlit, nm 0.2 0.2Flame Nitrous oxide-acetylene. Nitrous oxide-acetylene.Rich, red. Strongly reducing red cone 23cm high with yellow outeredge.9. Procedure9.1 Determination of Alumi
20、num:9.1.1 Accurately weigh 0.1 g (to the nearest 0.1 mg) ofzeolite standard (the same material expected in the test sample)into a clean, dry, platinum crucible. Also accurately weigh 0.2g of clay standard (the same material expected in the testsample) into another clean, dry, platinum crucible.9.1.2
21、 Grind a representative powdered detergent test samplein a blender to a fine, homogenous powder. (If a blender is notavailable, use a mortar and pestle).9.1.3 Accurately weigh 0.3 g (to the nearest 0.1 mg) of theground test sample(s) into still another clean, dry, platinumcrucible.9.1.4 Add2g(60.1 g
22、) of lithium metaborate to eachplatinum crucible, and mix the contents with a plastic rod.9.1.5 Place the crucibles containing the mixtures in a coolmuffle furnace and turn on the heat. When the temperaturereaches 1000C, maintain heat for at least 5 additional min.NOTE 1The sample will ignite and sp
23、latter if placed in a hot furnace.If it is not possible to start with a cool furnace, gently char the sample witha Fisher burner first, avoiding ignition, then place in the furnace.9.1.6 Place 90 mL of distilled water into 150-mL plasticbeakers. (Use as many beakers as there are standards andsamples
24、).9.1.7 Add a magnetic stirring bar to each beaker, and placeon a magnetic stirrer. Mix rapidly to make the water swirl inthe beaker, but do not allow anything to splash out. Thisapparatus should be near the furnace containing the ashedstandards and sample(s).9.1.8 Using platinum-tip tongs, remove o
25、ne crucible at atime from the furnace, and immediately place over a Fisherburner flame without allowing the melted sample to solidify.9.1.9 Add about 2 mg (a pinch on the end of a spatula) ofpotassium iodide (KI) to the melted sample. A molten ball willform. Roll the ball around the inside of the di
26、sh to pick up anydroplets or particles. The KI releasing agent is volatile, and itis necessary to carry out this step rather quickly (about 2 min).If the ball collapses and flows into the dish, start again byadding fresh KI.9.1.10 Drop each molten ball quickly into the swirling waterof each plastic
27、beaker.NOTE 2Precaution: Use face shield and protective clothing.9.1.11 Add 20 mL of 1 + 1 HCl and 20 mL of 1 %potassium chloride solution and mix until completely dis-solved. Quantitatively transfer to a 200-mL plastic volumetricflask with distilled water. Dilute to volume and mix well.9.1.12 Using
28、 a buret, add 5, 7.5, and 10 mL of 1000-ppmaluminum standard into 3 separate 100-mL plastic volumetricflasks. These standards contain 50, 75, and 100 g Al/mLrespectively. (Make these standards fresh each day).9.1.13 Add 10 mL 1 + 1 HCl, 10 mL 1 % KCl, and1goflithium metaborate to each flask. Dilute
29、to volume withdistilled water and mix until completely dissolved.9.1.14 Prepare a reagents blank.9.1.15 Set up the atomic absorption instrument as describedin 8.1.9.1.16 Zero the instrument with the reagents blank. Measurethe absorbance of the aluminum standards, the zeolite standard,the clay standa
30、rd and the test sample at 309.3 nm. Repeat themeasurement three more times for each flask and calculate theaverage absorbance. Save the solutions, except the aluminumstandards, for silicon determination in 9.2.9.1.17 Prepare a standard curve by plotting the averageabsorbance versus concentration in
31、g/mL of each aluminumstandard.7Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., an
32、d the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.8Available from Fisher Scientific Co., Fairlawn, NJ 07410.9Available from SPEX Industries, Box 798, Metuchen, NJ 08840.D 5547 95 (2003)29.1.18 Determine the concentration of aluminum in t
33、he testsample(s) by comparing the average absorbance to the standardcurve and reading aluminum concentration in g/mL directly.NOTE 3This test method describes manual data gathering and calcu-lation from a calibration curve so that the technique can be carried outusing all atomic absorption units. It
34、 is acceptable to use the automaticconcentration modes in modern atomic absorption units if so equipped.9.1.19 Calculation:C 3 200wt. 3 10 0005 % aluminum (1)where:C = aluminum concentration (g/mL),200 = final dilution in mL,wt. = weight of zeolite and clay standards, and testsample(s), in g, and10
35、000 = conversion factor, g/g to percent.9.2 Determination of Silicon:9.2.1 Pipet 5, 10, and 15 mL of 1000-ppm silicon standardinto three separate 100 mL plastic volumetric flasks.9.2.2 Add 10 mL 1 + 1 HCl, 10 mL 1 % KCl, and1goflithium metaborate to each flask. Dilute to volume withdistilled water a
36、nd mix until completely dissolved. Thesestandards contain 50, 100, and 150 g Si/mL respectively.(Make these standards fresh each day.)9.2.3 Prepare a reagents blank and dilute with distilled water50.0 mL of the clay standards from 9.1 to 100.0 mL in a100-mL plastic volumetric flask.9.2.4 Set up the
37、atomic absorption instrument as describedin 8.1.9.2.5 Zero the instrument with the reagents blank. Measurethe absorbance of the silicon standards at 251.6 nm. Measure,also at 251.6 nm, the absorbance of the zeolite standard, theclay standard, and the test sample(s) from 9.1. Repeat themeasurement th
38、ree more times for each flask and calculate theaverage absorbance.9.2.6 Prepare a standard curve by plotting the averageabsorbance versus concentration in g/mL of each siliconstandard.9.2.7 Determine the concentration of silicon in the testsample(s), the zeolite standard, and the clay standard bycom
39、paring the average absorbance to the standard curve andreading the silicon concentration in g/mL directly.NOTE 4This test method describes manual data gathering and calcu-lation from a calibration curve so that the technique can be carried outusing all atomic absorption units. It is acceptable to us
40、e the automaticconcentration modes in modern atomic absorption units if so equipped.9.2.8 Calculation:C 3 200wt. 3 10 0005 % silicon (2)where:C = silicon concentration from curve (g/L),200 = final dilution in mL,wt. = weight of zeolite and clay standards and testsample(s), in g, and10 000 = conversi
41、on factor, g/g to percent.10. Calculation of Percent Clay and Percent Zeolite inTest Samples10.1 Calculate the Si/Al ratio for the clay standard, thezeolite standard, and the test sample(s) from percent aluminumand percent silicon obtained in 9.1 and 9.2, respectively.10.2 Derive the equation of the
42、 straight line, y=mx+c,connecting the points:x1, y15 Si/Al C!, 0 (3)x2, y25 Si/Al Z!, 100where:Si/Al(C) = Si/Al ratio of clay standard,Si/Al(Z) = Si/Al ratio of zeolite standard,0 = concentration of zeolite in clay standard, and100 = concentration of zeolite in zeolite standard.10.3 Calculate the re
43、lative level of zeolite in the testsample(s) using the equation from 10.2 and the Si/Al ratio ofthe test sample(s) from 10.1:yRLZ! 5 mx 1 c (4)where:y(RLZ) = relative level of zeolite in the test sample,m = slope of the line (10.2),x = Si/Al ratio of test sample, andc = intercept of the line (10.2).
44、10.4 Percent Zeolite in Test Sample:ATS!RLZ!AZ!5 % zeolite (5)where:ATS = percent aluminum in test sample (9.1),RLZ = relative level of zeolite in test sample (10.3), andAZ = percent aluminum in zeolite standard.10.5 Percent Clay in Test Sample:ATS!100 2 RLZ!AC!5 % clay (6)where:ATS = percent alumin
45、um in test sample (9.1),RLZ = relative level of zeolite in test sample (10.3), andAC = percent aluminum in clay standard.10.6 Sample Calculation for a Typical Clay, Zeolite, andPowdered Detergent:10.6.1 Experimental Results:ClaystandardZeolitestandardPowderdetergent% Aluminum 8.8 16 3.3% Silicon 27.
46、3 17.6 5.4Si/Al ratio 3.1 1.1 1.6410.6.1.1 Using the points x1, y1= 3.1, 0; x2, y2= 1.1, 100,the equation of the line is:y 5250x 1 155 (7)10.6.1.2 Relative Level of Zeolite (RLZ) in Detergent Pow-der:D 5547 95 (2003)3y 5250!1.64! 1 155 5 73 (8)10.6.1.3 Percent Zeolite in Detergent Powder:ATS!RLZ!AZ!
47、53.3!73!16!5 15.1 (9)10.6.1.4 Percent Clay in Detergent Powder:ATS!100 2 RLZ!AC!53.3!100 2 73!8.8!5 10.1 (10)11. Precision and Bias11.1 Six laboratories collaborated in analyzing two powderdetergents (A and B). See Table 1.11.2 The standard deviations for clay, covering the 5.2 to9.9 % clay range, a
48、nd the standard deviations for zeolite,covering the 19.6 to 28.9 % zeolite range, were pooled. SeeTable 1.11.3 The following criteria should be used to judge theacceptability of the results.10,1111.3.1 Repeatability (Single Analyst) of ClayThe standarddeviation of results (each the average of duplic
49、ates), obtainedby the same analyst on different days, has been estimated to be0.7 % weight absolute, at 12 of freedom. Two such averagesshould be considered suspect (95 % confidence level) if theydiffer by more than 2.2 % weight absolute.11.3.2 Repeatability (Single Analyst) of ZeoliteThe stan-dard deviation of results (each the average of duplicates),obtained by the same analyst on different days, has beenestimated to be 1.0 % weight absolute, at 12 of freedom. Twosuch averages should be considered suspect (95 % confidencelevel
