1、Designation: E1754 08E1754 17Standard 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 case
2、 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 the
3、 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 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityo
4、f the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use. See Section 7 for specific hazards statements.1.4 Review the current Material Safety Data Sheets (MSDS)(SDS) for detailed information concerning tox
5、icity, first aidprocedures, and safety precautions.2. Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterE806 Test Method for Carbon Tetrachloride and Chloroform in Liquid Chlorine by Direct Injection (Gas ChromatographicProcedure)2.2 Federal Standards:349 CFR 173 Code of F
6、ederal Regulations Title 49 Transportation: ShippersShippersGeneral 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 C
7、ontainers3. Summary of Test Method3.1 A sample of liquid 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 o
8、ne obtained of the nitrogen-filled infrared cell previously. 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
9、 from a calibration curve prepared from the infrared absorbances ofstandards that contain known concentrations of water in liquid chlorine.4. 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 know
10、n to prevent problems during its use.1 This test method is under the jurisdiction of ASTM Committee D16 on Aromatic Hydrocarbons and Related Chemicals and is the direct responsibility of SubcommitteeD16.16 on Industrial and Specialty Product Standards.Current edition approved April 1, 2008March 1, 2
11、017. Published May 2008March 2017. Originally approved in 1995. Last previous edition approved in 20012008 asE1754 95 (2001)08. 1. DOI: 10.1520/E1754-08.10.1520/E1754-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annua
12、l 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, Government Printing Office, 732 N. Capitol St., NW, Washington, DC20402.20401-0001, http:/www.access.gpo.gov.Thi
13、s 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 recommends that users consult prior editio
14、ns 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 Box C700, West Conshohocken, PA 19428-2959.
15、United States15. Apparatus5.1 Infrared Spectrometer, 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 siz
16、e nor pathlength are critical to the analysis, but sensitivity and limit ofdetection are dependent on pathlength. The concentration range reported in the scope is achievable with a 60-mm pathlength cellconstructed with:5.2.1 Hastelloy C and 316 Stainless Steel Stock, suitable for machining.5.2.1 Sil
17、ver Chloride Windows, Hastelloy C and 316 Stainless Steel Stock, 0.5 by 2.5 cm. suitable for machining.NOTE 1Drawing not to scale.FIG. 1 Infrared CellE1754 172FIG. 1(a) Pipe AdapterFIG. 1(b) Air Cap DetailE1754 173FIG. 1(c) Body DetailFIG. 1(d) Gasket DetailE1754 174FIG. 1(e) Insert DetailFIG. 1(f)
18、Flange DetailE1754 175FIG. 1(a) Pipe AdapterFIG. 1(b) Air Cap DetailE1754 176FIG. 1(c) Body DetailFIG. 1(d) Gasket DetailE1754 177FIG. 1(e) Insert DetailFIG. 1(f) Flange DetailE1754 1785.2.2 Silver Chloride Windows, 0.5 by 2.5 cm.5.2.3 Perfluoroelastomer Sheet, 0.030 in. thickness.5.3 Ball Valves, M
19、onel414 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 6.35 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, wit
20、h valves at each end, speciallycleaned. Cylinders with both valves at one end and with a dip tube on one valve have been found 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 l
21、iquid chlorine, is given in Test Method E806, Appendix X2.5.5.2 Needle and Ball Valve, nickel body, having packing resistant 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
22、 nitrogen (less than 5 ppm water vapor).5.5.5 Fittings, for transferring chlorine from one cylinder to another.5.5.6 0 to 10- 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 shouldb
23、e supported by a wooden holder for safety purposes.5.5.8 Hygrometer, capable of measuring moisture as low as 5 mg/kg (ppm) 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
24、 5 mg/kg (ppm) water.6.3 Methylene Chloride (CH2Cl2).NOTE 2This reagent is used for cooling purposes only.6.4 Dry Ice (CO2).6.5 Dry Nitrogen, (5 mg/kg (ppm) water) to purge glove bag or dry box and test equipment.4 Monel is a registered trademark of Special Metals Corporation.FIG. 2 Sample Cylinder
25、AssemblyE1754 1797. 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 is analyzed in the laboratory.7.1.2 The analysis should be attempted only
26、 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 approved chlorine respirator. Splashes of liquid chlorine destroy clothing an
27、d 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 It is recommended that means be available for disposal of excess chlorin
28、e 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 purging of chlorine from a container, the purged chlorine should be similar
29、lyhandled. 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 point is associated with flowing chlorine, and isnot near a“ dead leg” where
30、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.Otherwise, temperature variations can result in water vapor condensing inside t
31、he piping to contaminate the chlorine sample whenit is grabbed. Finally, sampling should be done at a sample point representative of the chlorine needing to be analyzed.8.1.1 Sampling from tank cars, barges, storage tanks, and large cylinders presents unique problems. Each facility, however, mustbe
32、capable of delivering a liquid sample (not gas). Acceptable samples can be obtained by sampling in accordance with the SeeChlorine Institute Pamphlet No. 77, “Sampling Liquid Chlorine”1, “Chlorine Basics.”5.(See(See 49 CFR 173, including Parts173.304, 173.314, and 173.315.)8.2 It is recommended that
33、 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 allow the cylinder to become liquid full. Tare
34、 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: The cylinder holds 1000 g of water (1000 m
35、L, 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 preferably overnight;the dip tubes are not heated
36、, 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 removed, placed in a desiccator with a suit
37、able 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 valve, label these Cylinders No. 2 through
38、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 on all valves. If dip tubes are used, attach
39、 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 should contain less than 5 mg/kg (ppm) water
40、.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 the glove bag ordry box inside the hood. Pla
41、ce 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 and blow with N2 to remove any trapped moist
42、ure. 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 closed prior to filling the cell. Forthe follo
43、wing operations, refer to 7.1.4 on venting chlorine.5 Available from The Chlorine Institute, Inc., 2001 L St. NW, Washington, DC 20036.1300 Wilson Blvd., Suite 525, Arlington, VA 22209.E1754 17109.4 Open Valve F and then ValveA. Flush the filling apparatus by partially opening Valve B for a few seco
44、nds and then closingit. Leave Valve A open.9.4.1 Open Valves E and C. Flush the cell by partially opening 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 byopeni
45、ng Valve D. Close Valve D.9.6 Fill and empty the cell once more, as above.9.6.1 Close Valve A and open 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 t
46、o the apparatus in such a way that the liquid chlorine will flow into the cell and that the valves 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. Cl
47、ose Valve C and invert the cell to ensure complete filling of the cell window and thenclose Valve A.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 wind
48、ow should have about 15 vapor space when inverted.Then close Valves B and E.9.10 Allow the cell to 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 op
49、en and close Valve Ca 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 the spectrometer and scan in transmission mode from 400 to 4400 wavenumbers at 4-wavenumberresolution. Ratio this spectrum to a spectrum taken of the infrared cell filled with nitrogen. Then convert the ratioed transmissionspectrum to absorbance and measure the net absorbance of the band at 1596 wavenumber
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