1、Designation:D519406 Designation: D5194 11Standard Test Method forTrace Chloride in Liquid Aromatic Hydrocarbons1This standard is issued under the fixed designation D5194; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of
2、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. Scope*1.1 This test method covers the determination of total chloride (organic and inorganic) in liquid aromatic hydrocarbons a
3、ndcyclohexane.1.2 The test method is applicable to samples with chloride concentrations of 1 to 25 mg/kg.1.3 Bromides and iodides, if present, will be calculated as chlorides.1.4 Materials, such as styrene, that are polymerized by sodium biphenyl reagent cannot be analyzed by this test method.1.5In1
4、.5 In determining the conformance of the test results using this method to applicable specifications, results shall berounded off in accordance with the rounding-off method of Practice E29.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in
5、 this standard.1.7 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. F
6、or a specific hazard statement, see Section 7.2. Referenced Documents2.1 ASTM Standards:2D891 Test Methods for Specific Gravity, Apparent, of Liquid Industrial ChemicalsD1193 Specification for Reagent WaterD3437 Practice for Sampling and Handling Liquid Cyclic ProductsD3505 Test Method for Density o
7、r Relative Density of Pure Liquid ChemicalsD4052 Test Method for Density, Relative Density, and API Gravity of Liquids by Digital Density MeterD6809 Guide for Quality Control and Quality Assurance Procedures for Aromatic Hydrocarbons and Related MaterialsE29 Practice for Using Significant Digits in
8、Test Data to Determine Conformance with Specifications2.2 Other Documents:3OSHA Regulations, 29 CFR paragraphs 1910.1000 and 1910.12003. Summary of Test Method3.1 Aknown amount of hydrocarbon sample is transferred into a separatory funnel containing toluene. Sodium biphenyl reagentis added to conver
9、t organic halogens into inorganic halides. The excess reagent is decomposed with water and the phases areseparated. The aqueous phase is acidified, washed, and concentrated.Acetone is added and the solution is titrated with silver nitratesolution.4. Significance and Use4.1 Organic and inorganic chlo
10、rine compounds can have a deleterious effect on equipment and reactions in processes involvingaromatic hydrocarbons.4.2 Maximum chloride levels are often specified for process streams and for aromatic hydrocarbon products.5. Apparatus5.1 Titrator, potentiometric, recording, + 2000 mV range, 1 mV res
11、olution with dispenser having a volume readout of 0.00 to1This test method is under the jurisdiction of ASTM Committee D16 on Aromatic Hydrocarbons and Related Chemicals and is the direct responsibility of SubcommitteeD16.04 on Instrumental Analysis.Current edition approved MarchFeb. 1, 2006.2011. P
12、ublished March 2006.February 2011. Originally approved in 1991. Last previous edition approved in 20042006 asD5194 046. DOI: 10.1520/D5194-06.10.1520/D5194-11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at serviceastm.org. For Annual Book of
13、 ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3Available from U.S. Government Printing Office Superintendent of Documents, 732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http:/www.access.gpo.gov.1This document is not an ASTM standa
14、rd and is intended only to provide the user of an ASTM standard 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
15、only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.9.99 mL or 0.00 t
16、o 99.99 mL and 0.01 % resolution.5.2 Electrode, glass, reference.5.3 Electrode, silver, billet type.6. Reagents and Materials6.1 Purity of ReagentsReagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that allreagents conform to the specifications of the Comm
17、ittee on Analytical Reagents of the American Chemical Society, where suchspecifications are available.4Other grades may be used, provided it is first ascertained that the reagent is of sufficiently high purityto permit its use without lessening the accuracy of the determination.6.2 Purity of WaterUn
18、less otherwise indicated, references to water shall be understood to mean reagent water as defined byTypes II or III of Specification D1193.6.3 Acetone, 99.9 % purity.6.4 Congo Red Paper.6.5 Detergent, residue free.6.6 Isobutanol, 99.9 % minimum purity.6.7 Isooctane.6.8 Nitric Acid, concentrated.6.9
19、 Nitric Acid, 5-M. Dilute 160 mL concentrated nitric acid to 500 mL with water.6.10 Potassium Chloride, primary standard.6.11 Potassium Chloride Solution, saturated.6.12 Scouring Powder, cleanser.6.13 Silver Nitrate, 99.99 % minimum purity.6.14 Silver Nitrate Solution, 0.01 N, standardized to 0.1 %.
20、NOTE 1This solution may be obtained as follows:(1) Purchase from a laboratory supply company, (2) Weigh to four places, 1.680 to 1.720 g silver nitrate, transfer quantitatively into a 1000-mLvolumetric flask, make to mark with water, and mix well.Normality of solution 5Weight AgNO3169.9or (3) Dissol
21、ve 8.5 g silver nitrate in 500 mL water to give a 0.1 N solution. Weigh 0.09 to 0.10 g of dried (105C) potassium chloride to the nearest0.1 mg into a 250-mL electrolytic beaker, add 100 mL of water and a stirring bar. While stirring, titrate with the silver nitrate solution.Normality of AgNO3solutio
22、n 5Weight KCl0.0746 3 mL AgNO3Pipet 50.00 mL of the solution into a 500-mL volumetric flask, dilute to mark with water, and mix well. Divide the calculated normality of the 0.1 Nsolution by 10 to give the normality of final AgNO3solution.6.15 Sodium Biphenyl ReagentThe reagent is packed in 15-mL via
23、ls that contain 0.2 to 0.4 g of active sodium each.6.16 Toluene, 99.9 % minimum purity.7. Hazards7.1 Amaterial, such as styrene, which is polymerized by sodium biphenyl can cause a violent reaction and should never be usedas the sample.7.2 Consult current OSHA regulations and suppliers Material Safe
24、ty Data Sheets, and local regulations for all materials usedin this test method.8. Sampling8.1 Refer to Practice D3437 for proper sampling and handling of liquid hydrocarbons analyzed by this test method.9. Electrode Preparation9.1 Clean the surface of the silver electrode with mild detergent and sc
25、ouring powder, and rinse with water.4Reagent Chemicals, American Chemical Society Specifications, American Chemical Society, Washington, DC. For suggestions on the testing of reagents not listed bythe American Chemical Society, see Analar Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset,
26、U.K., and the United States Pharmacopeia and NationalFormulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD.TABLE 1 Specimen SizeEstimated chloride, mg/kg Specimen volume, mL0to5 1005to25 50D5194 1129.2 Immerse the electrode in the saturated potassium chloride solution until the electr
27、ode tip turns light gray.9.3 Rinse well with water and attach to the titrimeter.9.4 Repeat the electrode preparation when the silver chloride film begins to peel from the surface, or if the film becomesdiscolored.10. Procedure for Total Chloride10.1 Extreme care must be used to prevent contamination
28、 and all glassware should be exclusively reserved for this analysis. Justprior to use, the glassware should be rinsed with water followed by acetone and then air dried.10.2 Place 50 mL of toluene into a 250-mL separatory funnel and pipet in the amount of the liquid sample that corresponds tothe esti
29、mated chloride content as prescribed in Table 1.NOTE 2It is generally more convenient to measure the liquid samples by volume and then convert to mass using density or relative density. Table2 lists the relative densities of several pure hydrocarbons. Densities of unknowns may be determined by using
30、 Test Methods D891, D3505 or D4052.NOTE 3Alternately, place the sample into a 125-mL bottle and weigh. From the contents of this bottle add the appropriate amount of the sample tothe toluene in the separatory funnel. Reweigh the bottle, and determine the weight of the analytical specimen.10.3 Add th
31、e contents of one vial of sodium biphenyl reagent, stopper the separatory funnel, and gently swirl to mix thoroughly,venting the funnel from time to time. If the resulting solution or suspension is not blue-green, add more sodium biphenyl reagent(one vial at a time) until the blue green color persis
32、ts.NOTE 4The sodium biphenyl reagent has a limited shelf life, given as six months by the manufacturer. This can be extended, in most cases, toapproximately one year by keeping the reagent under refrigeration. If this is done, the reagent should be kept at room temperature for several days justprior
33、 to use to dissolve any sodium biphenyl that may have precipitated upon cooling.10.4 Allow the mixture to stand for approximately 10 min. Slowly add 20 mL water and swirl gently with the funnelunstoppered until the blue-green color changes to white. Stopper the funnel again and rock it gently for 1
34、min, venting the pressurefrequently through the stopcock.10.5 Add 10 mL 5 N nitric acid, and then 5 mL isobutanol. Shake gently, releasing the pressure frequently through the stopcock.10.6 Drain the aqueous phase into another 250-mL separatory funnel containing 50 mL isooctane and shake well. Drain
35、theaqueous phase into a 250-mL electrolytic beaker.10.7 Make a second extraction of the specimen solution with 20 mL water acidified with 6 drops of 5-M nitric acid and drainthe aqueous phase into the separatory funnel containing the isooctane. After shaking, allow the phases to separate and drain t
36、heaqueous phase into the beaker containing the first water extract.10.8 Test the aqueous solution with Congo red paper, and if it does not test acidic, add 5-N nitric acid dropwise with stirringuntil the test paper turns dark blue.10.9 Evaporate the solution to about 30 mL on a hot plate.10.9.1 Warn
37、ing: Loss of chloride may result if the solution is boiled or evaporated below 25 mL.10.10 Allow the solution to cool, and add 100 mL of acetone. Titrate the solution potentiometrically with standard 0.01 N silvernitrate solution and determine the volume of titrant used to reach the end point.10.11
38、Determine a blank for each group of samples, using all the reagents including as many vials of sodium biphenyl as wereused in the analysis of a sample. Follow all the operations of the analysis, except omit the specimen itself.11. Procedure for Inorganic Chloride11.1 Follow the procedure in Section
39、10 but without adding the sodium biphenyl reagent to either the sample or the blank.12. Procedure for Organic Chloride12.1 Follow the procedures given in Sections 10 and 11 to determine the total and inorganic chlorides. Subtract the inorganicfrom the total chloride to give the organic chloride.13.
40、Calculation13.1 Calculate either the total or inorganic chloride as follows:TABLE 2 Densities of HydrocarbonsComponent DensityBenzene 0.879Cyclohexane 0.779Ethylbenzene 0.867Isopropylbenzene 0.864Toluene 0.866m-Xylene 0.864o-Xylene 0.880p-Xylene 0.861D5194 113Chloride, mg/kg 535,500 A 2 B!VDN (1)whe
41、re:A = volume of titrant for aqueous phase, mL,B = volume of titrant for blank, mL,N = normality of silver nitrate solution,V = volume of sample, mL, andD = density or relative density of sample.D5194 11413.2 Calculate organic chloride as follows:Organic chloride, mg/kg 5 T 2 I (2)where:T = total ch
42、loride, mg/kg andI = inorganic chloride, mg/kg.13.3 Report chloride to the nearest 0.1 mg/kg.14. Precision and Bias14.1 Precision:14.1.1 The data for determining the precision of this test method are based on the analyses of toluene, ethylbenzene, andp-xylene that had been spiked with organic chlori
43、de compounds to the 1, 5, and 25 mg/kg chloride levels each.14.1.2 The following criteria should be used to judge the acceptability (95 % probability) of results obtained by this test method.The criteria were derived from a round robin between three laboratories. Each sample was run on two different
44、 days in eachlaboratory.14.1.2.1 Intermediate Precision (formerly called Repeatability)Results in the same laboratory should not be consideredsuspect unless they differ by more than 0.5 mg/kg.14.1.2.2 ReproducibilityResults from each of two laboratories should not be considered suspect unless they d
45、iffer by morethan 0.9 mg/kg.14.2 BiasThe bias of this test method cannot be determined because no referee method is available to determine the truevalue.15. Quality Guidelines15.1Refer to Guide15.1 Laboratories shall have a quality control system in place.15.1.1 Confirm the performance of the test i
46、nstrument or test method by analyzing a quality control sample following theguidelines of standard statistical quality control practices.15.1.2 A quality control sample is a stable material isolated from the production process and representative of the sample beinganalyzed.15.1.3 When QA/QC protocol
47、s are already established in the testing facility, these protocols are acceptable when they confirmthe validity of test results.15.1.4 When there are no QA/QC protocols established in the testing facility, use the guidelines described in Guide D6809 forsuggested QA/QC activities that can be used as
48、a part of this method. It is recommended that the operator of this method selectand perform relevant QA/QC activities like the ones on Guide D6809 to help ensure the quality of data generated by this method.or similar statistical quality control practices.16. Keywords16.1aromatic hydrocarbons; chlor
49、ide; cyclohexane; ethylbenzene; p-xylene; toluene16.1 aromatic hydrocarbons; chloride; cyclohexane; ethylbenzene; p-xylene; tolueneSUMMARY OF CHANGESCommittee D16 has identified the location of selected changes to this standard since the last issue(D519404)(D5194 - 06) that may impact the use of this standard. (Approved MarchFebruary 1, 2006.) 2011.)(1) The rounding statement was updated in 1.5.(2) Section 15 (Quality Control) was added and Guide D6809 was referenced.(3)Summary of Changes was added.Committee D16 has identified the location of selected changes to
