1、Designation: E776 87 (Reapproved 2009)E776 16Standard Test Method forDetermination of Forms of Chlorine in Refuse-Derived Fuel1This standard is issued under the fixed designation E776; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision
2、, 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 determination of the forms of chlorine in refuse-derived fuel-three (RDF): t
3、otal chlorine,water-soluble chloride, and water-insoluble chlorine.1.2 This test method may be applicable to any waste material from which a laboratory analysis sample can be prepared.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this
4、 standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use. For sp
5、ecific precaution statements see Section 6 and 11.2.1.2. Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterE144 Practice for Safe Use of Oxygen Combustion VesselsE180 Practice for Determining the Precision of ASTM Methods for Analysis and Testing of Industrial and Specialt
6、y Chemicals(Withdrawn 2009)3E287 Specification for Laboratory Glass Graduated BuretsE711 Test Method for Gross Calorific Value of Refuse-Derived Fuel by the Bomb Calorimeter (Withdrawn 2011)3E829 Practice for Preparing Refuse-Derived Fuel (RDF) Laboratory Samples for Analysis (Withdrawn 2002)33. Ter
7、minology3.1 Definitions of Terms Specific to This Standard:3.1.1 refuse-derived fuelssolid forms of refuse-derived fuels from which appropriate analytical samples may be prepared aredefined as follows in ASTM STP 832:4RDF-1Wastes used as a fuel in as-discarded form with only bulky wastes removed.RDF
8、-2Wastes processed to coarse particle size with or without ferrous metal separation.RDF-3Combustible waste fraction processed to particle sizes, 95 % passing 2-in. square screening.RDF-4Combustible waste fraction processed into powder form, 95 % passing 10-mesh screening.RDF-5Combustible waste fract
9、ion densified (compressed) into the form of pellets, slugs, cubettes, or briquettes.3.1.2 total chlorineall chlorine as determined in the refuse-derived fuel.3.1.3 water-insoluble chlorinewater-insoluble chlorides and chlorine in the refuse-derived fuel.3.1.4 water-soluble chloridethose chlorides wh
10、ich are water-solubilized by water extraction as determined in the refuse-derived fuel.4. Summary of Test Method4.1 The forms of chloride and chlorine are determined. The various procedures in the method convert the forms of chlorine intoa water-soluble chloride form that can be quantitated by titra
11、tion.1 This test method is under the jurisdiction of ASTM Committee D34 on Waste Management and is the direct responsibility of Subcommittee D34.03 on Treatment,Recovery and Reuse.Current edition approved July 1, 2009Feb. 1, 2016. Published August 2009February 2016. Originally approved in 1981. Last
12、 previous edition approved in 2004 asE 776 87 (2004).2009 as E776 87 (2009). DOI: 10.1520/E0776-16.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Docu
13、ment Summary page on the ASTM website.3 The last approved version of this historical standard is referenced on www.astm.org.4 Thesaurus on Resource Recovery Terminology, ASTM STP 832, ASTM, 1983, p. 72.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard
14、 an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is
15、 to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14.1.1 Total ChlorineThe sample is combusted in an oxygen atmosphere. The chlorine is converted to chloride and absorbedin an alkaline solution.4.1
16、.2 Water-Soluble ChloridesA portion of the analysis sample is successively extracted with hot chloride-free water.4.1.3 Water-Insoluble ChlorineWater-insoluble chlorine is calculated from the results of the total chlorine and thewater-soluble chloride determination where:water2insoluble chlorine5tot
17、al chlorine2water2soluble chlorides (1)4.2 The chlorides contained in the alkaline solution (4.1.1) and the extraction solution (4.1.2) are determined by potentiometric(see Section 13) or modified Volhard titration (see Section 14).5. Significance and Use5.1 The standard is available to producers an
18、d users of RDF for determining the content and forms of chlorine present in thefuel.6. Precautions6.1 Due to the origins of RDF in municipal waste, common sense dictates that some precautions should be observed whenconducting tests on the samples. Recommended hygienicsafety practices include use of
19、gloves when handling RDF; wearing dustmasks (NIOSH-approved type), especially while milling RDF samples; conducting tests under negative pressure hood whenpossible; and washing hands upon completion of activity and before eating or smoking.7. Interferences7.1 Potentiometric Titration Method A:7.1.1
20、Iodide and bromide are also titrated interferences that will titrate as chloride. Ferricyanide causes high biased results andmust be removed. Chromate and dichromate interfere and should be reduced to the chromic state or be removed. Ferric ironinterferes if present in an amount substantially higher
21、 than the amount of chloride. Chromic ions, ferrous ions, and phosphates donot interfere.7.1.2 Grossly contaminated sample solutions usually require pretreatment. Where contamination is minor, some contaminantscan be destroyed simply by the addition of nitric acid.7.2 Volhard Titration Method B:7.2.
22、1 Compounds that have a strong oxidizing action interfere by reacting with thiocyanate. These compounds should bereduced beforehand by treatment with ferrous sulfate or a similar reducing agent.7.2.2 Salts of mercury and palladium interfere by reacting with thiocyanate. They may be removed by precip
23、itation withhydrogen sulfide before the addition of silver nitrate. The excess of sulfide is easily removed by gently boiling the acid solutionfor a few minutes. Sulfite can be eliminated in the same way.FIG. 1 Graph From a Potentiometric Titration of ChlorideE776 1627.2.3 Cyanide is also precipitat
24、ed by silver nitrate. It is usually determined separately by the Liebig-Deniges method and acorrection is applied to the results of the Volhard titration.57.2.4 The Volhard method, as with the potentiometric method, directly applied to a mixture of halides can determine only totalhalide content excl
25、uding fluoride. Preliminary treatment is necessary for the determination of chloride alone in a mixture.68. Apparatus8.1 Balance, having a sensitivity of balance capable of weighing with an accuracy of 0.1 mg.8.2 Apparatus for Bomb Combustion of the Sample.8.2.1 Oxygen Bomb, similar to that used in
26、the determination of the calorific value of refuse-derived fuels as described in TestMethod E711.8.2.2 Capsule, for holding the sample, approximately 25 mm 25 mm in diameter at the top, approximately 12 mm deep, andconforming to Test Method E711.8.2.3 Firing Wire, as specified in Test Method E711.8.
27、2.4 Firing Circuit, as specified in Test Method E711.8.2.5 Metal Vessel, cylindrical, such that the bomb will be fully immersed when approximately 2 L of water are added.8.3 Magnetic Stirrer and Stirring Bars.8.4 Apparatus for Potentiometric Titration:8.4.1 Potentiometric Titration Assembly, using a
28、 silver indicator electrode and a calomel reference electrode containing asaturated sodium nitrate solution as a bridge.NOTE 1All glassware and graduated apparatus should be Class A or equivalent as described in Specification E287.8.5 Centrifuge, capable of centrifuging 100-mL centrifuge tubes at ap
29、proximately 1200 rpm.8.6 Centrifuge Tubes, for chloride solution preparation (alternative method).8.7 Filter Paper, used to filter chloride solution.NOTE 1All glassware and graduated apparatus should be Class A or equivalent as described in Specification E287.9. Reagents9.1 Purity of ReagentsReagent
30、 grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that allreagents shall conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society wheresuch specifications are available.7 Other grades may be used, provided it is firs
31、t ascertained that the reagent is of sufficiently highpurity to permit its use without lessening the accuracy of the determination.9.2 Purity of WaterUnless otherwise indicated, reference to water shall be understood to mean at least Type III reagent waterconforming to Specification D1193.9.3 Potass
32、ium Hydroxide Solution (0.2 N)Dissolve 13.2 g of potassium hydroxide (KOH) in water and dilute to 1 L withwater.9.4 OxygenThe oxygen used for combustion shall be free of combustible matter. Oxygen manufactured from liquid air,guaranteed to be greater than 99.5 % pure, will meet this requirement.9.5
33、Sodium Chloride (NaCl)Primary standard quality (purity of 100 6 0.02 %).9.6 Sodium Chloride, Primary Standard Solution (0.025 (0.025 N)Crush 10 to 20 g of primary standard sodium chloride(NaCl) to 100-mesh fineness and dry in a glass container at 120C for 2 h. Stopper and keep desiccated. Dissolve 5
34、.844 g 6 0.1mg of dried primary standard NaCl in water and dilute to 1 L. Dilute 25.00 mL of this solution to 100.0 mL.9.7 Methanol.9.8 Nitric Acid (1 + 1)Mix equal volumes of concentrated nitric acid (HNO3, sp, gr, 1.42) and water.9.9 Silver Nitrate, Standard Solution (0.025 N)Dissolve 4.247 g of s
35、ilver nitrate (AgNO3) in water and dilute to 1 L. 1 L. Storein an amber glass bottle. Standardize against 0.025 N sodium chloride solution as directed in 13.1.113.1 and 14.1.1.9.10 Potassium Chromate Potassium Dichromate Indicator(K2CrO4 K2Cr2O7)Dissolve 4.2 g of K2CrO4 and 0.7 g ofK2Cr2O7 in 100 mL
36、 of water.9.11 Nitrobenzene.5 Scotts Standard Method of Chemical Analysis, edited by M. H. Furman, D. Van Nostrand Co., Inc., New York, NY.6 Koltoff, I. M., and Stenger, V. A., Volumetric Analysis II, Interscience Publishers, Inc., New York, NY.7 Reagent Chemicals, American Chemical Society Specific
37、ations, American Chemical Society, Washington, DC. For Suggestions on the testing of reagents not listed bythe American Chemical Society, see Annual Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia and NationalFormulary, U.S. Pharmacopeial Convent
38、ion, Inc. (USPC), Rockville, MD.E776 1639.12 Ferric Ammonium Sulfate Indicator SolutionAdd sufficient concentrated HNO3 (sp gr 1.42) to a cold saturated solutionof ferric ammonium sulfate FeNH4(SO4)212H2O to remove the brown color.9.13 Potassium Thiocyanate, Standard Solution (0.025 N)Dissolve 3 g o
39、f potassium thiocyanate (KCNS) in freshly distilledor boiled water, dilute to 1 L, and standardize against 0.025 N AgNO3 solution as directed in 14.1.2.10. Sampling10.1 RDF products are frequently nonhomogeneous.inhomogeneous. For this reason significant care should be exercised toobtain a represent
40、ative laboratory sample from the RDF lot to be characterized.10.2 The sampling method for this procedure should be based on agreement between the involved parties.10.3 The laboratory sample must be air-dried and the particle size reduced to pass through a 0.5-mm screen as described inPractice E829.
41、This procedure must be performed carefully to preserve the samples representative characteristics (other thanparticle size)representativeness beyond just particle size while preparing the analysis sample to be used in the analyzed inaccordance with these procedures.PREPARATION OF CHLORINE SOLUTIONS
42、FOR ANALYSIS11. Total Chlorine (Oxygen Bomb Method)11.1 Preparation of Sample and Bomb (see Note 3):11.1.1 Sample WeightWeigh to the nearest 0.1 mg about 1 g of thoroughly mixed air-dried analysis RDF sample into theabomb capsule. A pellet may be made from the air-dried analysis RDF sample, accurate
43、ly weighed, and placed into the bombcapsule. Place the capsule containing the sample into the capsule holder.NOTE 2There is a tendency for chlorine to adhere to the bomb walls, especially if the bomb is pitted or has been used previously to determine highlevels of chlorine. Unless the bomb is thorou
44、ghly cleaned before use, the blanks may have values in excess of reality.high background chlorine values.11.1.2 Firing WireConnect a length of firing wire to the ignition terminals in such a manner that the loop of firing wire is incontact with the sample.11.1.3 Bomb PreparationAdd 20 to 25 mL of 0.
45、02 N potassium hydroxide solution to the bomb and wet the entire internalsurface of the bomb with this solution (see Note 3). Assemble the bomb.NOTE 3Sodium hydroxide solution at appropriate concentration may be used.11.2 Addition of OxygenAdmit oxygen to the bomb slowly to avoid blowing the sample
46、from the capsule until a pressure of25 atm is reached.11.2.1 WarningThe following precautions are recommended for safe calorimeter operation.Additional precautions are givenin Practice E144.11.2.1.1 The weight of RDF sample and the pressure of the oxygen admitted to the bomb must not exceed the bomb
47、manufacturers recommendations.11.2.1.2 Bomb parts should be inspected carefully after each use. Threads on the main closure should be checked frequentlyfor wear. Cracked or significantly worn parts should be replaced. The bomb should be returned to the manufacturer occasionallyfor inspection and pos
48、sibly proof firing.11.2.1.3 The oxygen supply cylinder should be equipped with an approved type of safety device, such as a reducing valve, inaddition to the needle valve and pressure gage used in regulating the oxygen feed to the bomb. Valves, gages, and gaskets mustmeet industry safety codes. Suit
49、able reducing valves and adaptors for 300 to 500 psi (2070 to 3450 kPa) discharge pressures areobtainable from commercial sources of compressed gas equipment. The pressure gagegauge shall be checked periodically foraccuracy.11.2.1.4 During ignition of a sample, the operator must not permit any portion of his body to extend over the calorimeter.11.3 Preparation of the Chlorine SolutionImmerse the bomb in a cold-water bath, connect it to the firing circuit, and closethe circuit to ignite the sample. Allow the bomb to stand in the wate
