ASTM E1754-2017a Standard Test Method for Determination of Low Levels of Water in Liquid Chlorine By Infrared Spectrophotometry《采用红外分光光度法测定液态氯中低含水量的标准试验方法》.pdf

《ASTM E1754-2017a Standard Test Method for Determination of Low Levels of Water in Liquid Chlorine By Infrared Spectrophotometry《采用红外分光光度法测定液态氯中低含水量的标准试验方法》.pdf》由会员分享，可在线阅读，更多相关《ASTM E1754-2017a Standard Test Method for Determination of Low Levels of Water in Liquid Chlorine By Infrared Spectrophotometry《采用红外分光光度法测定液态氯中低含水量的标准试验方法》.pdf（15页珍藏版）》请在麦多课文档分享上搜索。

1、Designation: E1754 17E1754 17aStandard Test Method forDetermination of Low Levels of Water in Liquid Chlorine ByInfrared Spectrophotometry1This standard is issued under the fixed designation E1754; the number immediately following the designation indicates the year oforiginal adoption or, in the cas

2、e of revision, 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. Scope*1.1 This test method covers the determination of the content of water in liquid chlorine in th

3、e concentration range of 0.5 to 15mg/kg (ppm).1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.1.3 Review the current Safety Data Sheets (SDS) for detailed information concerning toxicity, first aid procedures, and safetypreca

4、utions.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. See Secti

5、on 7 for specific hazards statements.1.4 Review the current Safety Data Sheets (SDS) for detailed information concerning toxicity, first aid procedures, and safetyprecautions.1.5 This international standard was developed in accordance with internationally recognized principles on standardizationesta

6、blished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterD6809 Guide for Quality C

7、ontrol and Quality Assurance Procedures for Aromatic Hydrocarbons and Related MaterialsE806 Test Method for Carbon Tetrachloride and Chloroform in Liquid Chlorine by Direct Injection (Gas ChromatographicProcedure)2.2 Federal Standards:349 CFR 173 Code of Federal Regulations Title 49 Transportation:

8、Shippers General Requirements for Shipments andPackaging, including Sections:173.304 Charging of Cylinders with Liquefied Compressed Gas173.314 Requirements for Compressed Gases in Tank Cars173.315 Compressed Gases in Cargo Tanks and Portable Tank Containers3. Summary of Test Method3.1 A sample of l

9、iquid chlorine is introduced into a special infrared cell and maintained as a liquid under its own pressure. Aspectrometer scans from 400 to 4400 wavenumbers of the infrared transmission spectrum of liquid chlorine. This spectrum is thenratioed to one obtained of the nitrogen-filled infrared cell pr

10、eviously. The ratioed spectrum is converted to absorbance, and the netabsorbance of the water band at 1596 wavenumbers, relative to a reference at 1663 wavenumbers, is determined. The amount ofwater corresponding to this net absorbance is determined from a calibration curve prepared from the infrare

11、d absorbances ofstandards that contain known concentrations of water in liquid chlorine.1 This test method is under the jurisdiction of ASTM Committee D16 on Aromatic Hydrocarbons Aromatic, Industrial, Specialty and Related Chemicals and is the directresponsibility of Subcommittee D16.16 on Industri

12、al and Specialty Product Standards.Current edition approved March 1, 2017July 1, 2017. Published March 2017July 2017. Originally approved in 1995. Last previous edition approved in 20082017 as E1754 08.17. DOI: 10.1520/E1754-17.10.1520/E1754-17a.2 For referencedASTM standards, visit theASTM website,

13、 www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Available from U.S. Government Printing Office, Superintendent of Documents, 732 N. Capitol St., NW, Washington,

14、DC 20401-0001, http:/www.access.gpo.gov.This document is not an ASTM standard 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

15、 recommends that users consult prior editions as appropriate. In all cases 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 standardCopyright ASTM International, 100 Barr Harbor Drive, PO B

16、ox C700, West Conshohocken, PA 19428-2959. United States14. Significance and Use4.1 Trace amounts of water may be detrimental to the use of chlorine in some applications. The amount of water in the chlorinemust be known to prevent problems during its use.E1754 17a25. Apparatus5.1 Infrared Spectromet

17、er, capable of measurements in the 1600 wavenumber region. An FTIR with 4 wavenumber resolutionis the instrument of choice, but dispersive instruments may also be used to achieve similar results.5.2 Special Infrared Cell (see Fig. 1), neither cell size nor pathlength are critical to the analysis, bu

18、t sensitivity and limit ofdetection are dependent on pathlength. The concentration range reported in the scope is achievable with a 60-mm pathlength cellconstructed with:NOTE 1Drawing not to scale.FIG. 1 Infrared CellE1754 17a3FIG. 1(a) Pipe AdapterFIG. 1(b) Air Cap DetailE1754 17a4FIG. 1(c) Body De

19、tailFIG. 1(d) Gasket DetailE1754 17a5FIG. 1(e) Insert DetailFIG. 1(f) Flange DetailE1754 17a65.2.1 Hastelloy C and 316 Stainless Steel Stock, suitable for machining.FIG. 1(a) Pipe AdapterFIG. 2 Sample Cylinder AssemblyE1754 17a7FIG. 1(b) Air Cap DetailFIG. 1(c) Body DetailE1754 17a8FIG. 1(d) Gasket

20、DetailFIG. 1(e) Insert DetailFIG. 1(f) Flange DetailE1754 17a95.2.2 Silver Chloride Windows, 0.5 by 2.5 cm.5.2.3 Perfluoroelastomer Sheet, 0.030 in. thickness.5.3 Ball Valves, Monel414 in. valve with pipe and 14 in. tube ends.5.4 Needle Valves, nickel or Monel4 6.35 mm (14 in.) valve with pipe and 6

21、.35 mm (14 in.) tube ends.5.5 Sample Cylinder Assembly (see Fig. 2), consisting of:5.5.1 Sample Cylinder, nickel, Monel,4 or tantalum; 400 to 1000 mL capacity, double-ended, with valves at each end, speciallycleaned. Cylinders with both valves at one end and with a dip tube on one valve have been fo

22、und to be satisfactory.Another optionis to construct special cylinders containing a septum fitting on one end.NOTE 1A procedure for cleaning cylinders and valves, for use with liquid chlorine, is given in Test Method E806, Appendix X2.5.5.2 Needle and Ball Valve, nickel body, having packing resistan

23、t to liquid chlorine. If nickel valves are not available, Monel4valves may be used.5.5.3 Septum, inserted into a 6.35 mm (14 in.) nut.5.5.4 Glove Bag or Dry Box, purged with dry nitrogen (less than 5 ppm water vapor).5.5.5 Fittings, for transferring chlorine from one cylinder to another.5.5.6 0 to 1

24、0- L Syringe and 0 to 25-L Syringe, 26-gage needle.5.5.7 Dewar Flask, of sufficient size to hold a cylinder surrounded by dry ice and methylene chloride. The Dewar flask shouldbe supported by a wooden holder for safety purposes.5.5.8 Hygrometer, capable of measuring moisture as low as 5 mg/kg (ppm)

25、in glove bag or dry box.5.6 Silicone Rubber Septa.5.7 Mechanical Shaker.5.8 Drying Oven.6. Reagents6.1 Purity of WaterSee Specification D1193.6.2 Chlorine, liquid with less than 5 mg/kg (ppm) water.6.3 Methylene Chloride (CH2Cl2).NOTE 2This reagent is used for cooling purposes only.6.4 Dry Ice (CO2)

26、.6.5 Dry Nitrogen, (5 mg/kg (ppm) water) to purge glove bag or dry box and test equipment.7. Hazards7.1 Safety Precautions:7.1.1 Chlorine is a corrosive and toxic material.Awell-ventilated fume hood should be used to house all test equipment, exceptthe infrared spectrophotometer, when this material

27、is analyzed in the laboratory.7.1.2 The analysis should be attempted only by persons who are thoroughly familiar with the handling of chlorine, and evenan experienced person should not work alone. The analyst must be provided with adequate eye protection (chemical goggles arerecommended) and an appr

28、oved chlorine respirator. Splashes of liquid chlorine destroy clothing and if such clothing is next to theskin, will produce irritation and burns.7.1.3 When sampling and working with chlorine out of doors, people downwind from such operations should be warned of thepossible release of chlorine.7.1.4

29、 It is recommended that means be available for disposal of excess chlorine in an environmentally safe and acceptablemanner. If chlorine cannot be disposed of in a chlorine consuming process, a chlorine absorption system should be provided. Whenthe analysis and sampling regimen requires an initial pu

30、rging of chlorine from a container, the purged chlorine should be similarlyhandled. Purging to the atmosphere should be avoided.7.1.5 In the event chlorine is inhaled, first aid should be summoned immediately.8. Sampling8.1 Sampling points should also be chosen with care. Ensure that the sample poin

31、t is associated with flowing chlorine, and isnot near a“ dead leg” where the concentrations of impurities in the chlorine will never change because the chlorine never moves.If sampling through secondary piping, that piping should be purged well with nitrogen or dry air before being blocked in.4 Mone

32、l is a registered trademark of Special Metals Corporation.E1754 17a10Otherwise, temperature variations can result in water vapor condensing inside the piping to contaminate the chlorine sample whenit is grabbed. Finally, sampling should be done at a sample point representative of the chlorine needin

33、g to be analyzed.8.1.1 Sampling from tank cars, barges, storage tanks, and large cylinders presents unique problems. Each facility, however, mustbe capable of delivering a liquid sample (not gas). See Chlorine Institute Pamphlet No. 1, “Chlorine Basics.”5(See 49 CFR 173,including Parts 173.304, 173.

34、314, and 173.315.)8.2 It is recommended that samples be collected from these facilities in the sample cylinder assembly listed in 5.5. Proper andsafe sampling techniques must be followed. The cylinder must contain at least 75 % by volume of liquid chlorine (less than 25 %vapor space).NOTE 3Do not al

35、low the cylinder to become liquid full. Tare the cylinder, fill with water, and re-weigh to determine the weight of water in thecylinder. Multiply this weight by 1.56 (the assumed specific gravity of liquid chlorine) and by 0.75 to obtain the weight of chlorine to fill the cylinder75 % full. Example

36、: The cylinder holds 1000 g of water (1000 mL, assuming a specific gravity of 1.0). The filled cylinder will hold 1560 g of chlorine,and at 75 % of capacity, it will contain 1170 g of chlorine.8.3 The sample cylinders should be thoroughly dried by placing in an oven at 105C for at least 6 h or prefe

37、rably overnight;the dip tubes are not heated, place them in a desiccator.Valves are also placed in the oven, but not as a part of the cylinder (packingsare resistant to this temperature). After this treatment, the cylinders are cooled with plant air or N2 having 5 mg/kg (ppm)moisture. The valves are

38、 removed, placed in a desiccator with a suitable drying agent, and cooled to room temperature.9. Preparation of Standards for Calibration9.1 Obtain four clean, evacuated sample cylinders. Only cylinders that have been properly pressure-tested should be used. Equipthree with a ball valve and a needle

39、 valve, label these Cylinders No. 2 through No. 4 and record weight to the nearest gram. Equipthe fourth cylinder with two needle valves, weigh to the nearest gram, record, and label as No. 1. Once it contains chlorine, it willbe used to purge the infrared cell before standards are loaded. Use caps

40、on all valves. If dip tubes are used, attach the dip tubeto the needle valve. Check the hygrometer to make sure the atmosphere in the glove bag or dry box contains 5 mg/kg (ppm)moisture before performing any transfers of chlorine.9.2 Load the four cylinders with liquid chlorine. The liquid chlorine

41、should contain less than 5 mg/kg (ppm) water.All cylindersmust contain at least 75 % by volume liquid chlorine (less than 25 % vapor space). All cylinders should be weighed to the nearestgram and recorded to determine the weight of chlorine in each cylinder (Note 3). Place the filled cylinders into

42、the glove bag ordry box inside the hood. Place all fittings, tools and equipment, including the purged infrared cell, in the glove bag or dry box.Wait until the hygrometer in the glove bag or dry box is reading 5 mg/kg (ppm) moisture before proceeding.9.3 Remove the cap on Valve A of Cylinder No. 1

43、and blow with N2 to remove any trapped moisture. Do this each time aconnection is made. Then connect the cylinder and the special infrared cell to the filling apparatus (see Fig. 2) in such a way thatthe liquid chlorine will flow into the cell and that the valves on all parts of the apparatus are cl

44、osed prior to filling the cell. Forthe following operations, refer to 7.1.4 on venting chlorine.9.4 Open Valve F and then ValveA. Flush the filling apparatus by partially opening Valve B for a few seconds and then closingit. Leave Valve A open.9.4.1 Open Valves E and C. Flush the cell by partially o

45、pening Valve D and observing flow, then close Valve C and then ValveD.9.5 Fill the infrared cell by opening Valve C and observe the filling of the cell windows. Close Valve C and empty the cell byopening Valve D. Close Valve D.9.6 Fill and empty the cell once more, as above.9.6.1 Close Valve A and o

46、pen Valve B, to purge the filling apparatus, then close.9.7 Remove the cylinder. Connect Cylinder No. 2 to the filling apparatus after blowing Valve A with N2. Make sure that thecylinder is connected to the apparatus in such a way that the liquid chlorine will flow into the cell and that the valves

47、on all partsof the apparatus are closed prior to attempting to fill the cell. For the following operations, refer to 7.1.4 on venting chlorine. Repeat9.4 to 9.6.9.8 Fill the cell by opening Valve C. Close Valve C and invert the cell to ensure complete filling of the cell window and thenclose Valve A

48、.9.9 Vent the residual chlorine from the filling apparatus by opening Valve B and then open Valve C a little and dump a smallamount of chlorine from the inverted cell, then quickly close. The cell window should have about 15 vapor space when inverted.Then close Valves B and E.9.10 Allow the cell to

49、come to ambient temperature. Before removing the cell from the filling apparatus, check again foradequate vapor space in the inverted cell window. If no vapor space is seen, open Valve B and quickly open and close Valve C5 Available from The Chlorine Institute, Inc., 1300 Wilson Blvd., Suite 525, Arlington, VA 22209.E1754 17a11a little to dump some more chlorine. Make sure that no more than 14 to 15 of the cell window is vapor space when the cell isinverted. Remove Cylinder No. 1 and No. 2 and record their weights.9.11 Place the infrared cell in