1、Designation: D 4458 05Standard Test Method forChloride Ions in Brackish Water, Seawater, and Brines1This standard is issued under the fixed designation D 4458; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisi
2、on. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method2is applicable to the measurement ofchloride in highly mineralized waters such as oil field brines,seawater, an
3、d brackish water. The test method is based uponthe titration of chloride with silver nitrate, using a visualindicator.1.2 Samples containing from 10 to 150 mg of chloride canbe analyzed by this test method. These levels are achieved bydilution as described in the test method.1.3 It is the users resp
4、onsibility to assure the validity of themethod for untested types of water.1.4 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 practices and determin
5、e the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3D 1129 Terminology Relating to WaterD 1193 Specification for Reagent WaterD 2777 Practice for Determination of Precision and Bias ofApplicable Methods of Committee D19 on WaterD 3370 Practices for
6、Sampling Water from Closed ConduitsD 5810 Guide for Spiking into Aqueous SamplesD 5847 Practice for Writing Quality Control Specificationsfor Standard Test Methods for Water Analysis3. Terminology3.1 DefinitionsFor definitions of terms used in this testmethod, refer to Terminology D 1129.4. Summary
7、of Test Method4.1 This test method is based upon the Mohr procedure fordetermining chloride ion with silver nitrate. The chloride reactswith the silver ion before any silver chromate forms, due to thelower solubility of silver chloride. The potassium chromateindicator reacts with excess silver ion t
8、o form a red silverchromate precipitate. The end point is the appearance of thefirst permanent orange color.4.2 This test method is suitable for analyzing solutions witha pH between 6.0 and 8.5.5. Significance and Use5.1 Chloride is present in virtually all oil field brines,seawaters, and many waste
9、 waters. Identification of the originof the water and selection of its disposal method may be basedupon the chloride content. The chloride content is also used toestimate the resistivity of formation waters and to differentiatebetween subsurface formations.6. Interferences6.1 Sulfide, bromide, iodid
10、e, thiocyanate, cyanide, phos-phate, sulfite, carbonate, hydroxide, and iron interfere in thistest method. Sulfide, sulfite, and thiosulfate can be removedwith a peroxide treatment, but usually no attempt is made toremove bromide and iodide because they are usually present ininsignificant quantities
11、 compared to chloride. If necessary, thepH can be raised and the hydroxides of several metals,including iron, can be filtered off. Iron, barium, lead, andbismuth precipitate with the chromate indicator.7. Apparatus7.1 Laboratory Glassware.7.2 Buret, 25-mL capacity.7.3 Hotplate.7.4 Magnetic Stirrer a
12、nd TFE-fluorocarbon-Coated StirringBars.8. Reagents8.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specification of the Committee1This test method is under the jurisdiction of ASTM Committee D19
13、 on Waterand is the direct responsibility of Subcommitee D19.05 on Inorganic Constituents inWater.Current edition approved Aug. 15, 2005. Published August 2005. Originallyapproved in 1985. Last previous edition approved in 1994 as D 4458 85 (1999).2Hillebrand, W. F., Lundell, G. E. F., Bright, H. A.
14、, and Hoffman, J. I., AppliedInorganic Analysis, 2nd Ed., 732, John Wiley brines; chloride ion; seawater; silvernitrateSUMMARY OF CHANGESCommittee D19 has identified the location of selected changes to this standard since the last version(D 4458 94 (1999) that may impact the use of this standard.(1)
15、 Added Guide D 5810 and Practice D 5847 to 2.(2) Revised 8.2 to use Type I water.(3) Changed the reference in 12.1 to Table 2.(4) Updated 12.5 to include the current D 2777 reference.(5) Added Section 13.ASTM International takes no position respecting the validity of any patent rights asserted in co
16、nnection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the respo
17、nsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful
18、 consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International,
19、100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D 4458 054
