1、BRITISH STANDARD BS579:1957 Specification for Diethyl ether (technical)BS579:1957 This BritishStandard, having been approved by the Fine andHeavy Chemicals IndustryStandards Committeeand endorsed bythechairman of the ChemicalDivisional Council, waspublished by the authorityofthe General Councilon 31
2、December1957 BSI12-1999 First published November1934 First revision March1951 Second revision December1957 The following BSI references relate to the work on this standard: Committee reference FHC/4 and FHC/4/5 Draft for comment CX(FHC)2046 ISBN 0 580 34006 6 Co-operating organizations The Fine and
3、Heavy Chemicals Industry Standards Committee, under whose supervision this BritishStandard was prepared, consists of representatives from the following Government departments and scientific and industrial organizations: Association of British Chemical Manufacturers* Board of Trade British Iron and S
4、teel Federation British Railways, The British Transport Commission Fertilizer Manufacturers Association Gas Council Institution of Gas Engineers Ministry of Health Ministry of Supply* National Sulphuric Acid Association The Government department and industrial organization marked with an asterisk in
5、 the above list, together with the following, were directly represented on the committees entrusted with the preparation of this BritishStandard: Admiralty Association of Cellulose Lacquer Manufacturers British Plastics Federation Department of the Government Chemist Institute of Petroleum National
6、Paint Federation Oil and Colour Chemists Association Pharmaceutical Society of Great Britain Royal Institute of Chemistry Society for Analytical Chemistry Society of Chemical Industry Society of Motor Manufacturers and Traders Ltd. Individual manufacturers Amendments issued since publication Amd. No
7、. Date CommentsBS579:1957 BSI 12-1999 i Contents Page Co-operating organizations Inside front cover Foreword ii 1 Description 1 2 Specific gravity 1 3 Distillation range 1 4 Water 1 5 Residue on evaporation 1 6 Acidity 1 7 Peroxides 1 8 Sulphur compounds 1 9 Sample 1 Appendix A Method for the determ
8、ination of distillation range 2 Appendix B Method for the determination of residue on evaporation 4 Appendix C Method for the determination of acidity 4 Appendix D Method for the detection of peroxides 4 Appendix E Method for the detection of sulphur compounds 5 Figure 1 Assembly of distillation fla
9、sk, draught screen and water bath 3BS579:1957 ii BSI 12-1999 Foreword This standard makes reference to the following BritishStandards: BS571, Flasks for the determination of distillation range. BS593, Laboratory thermometers. BS604, Graduated measuring cylinders. BS605, Distillation receivers (inclu
10、ding Crow receivers). BS658, Apparatus for the determination of distillation range. BS2511, Determination of water by the Karl Fischer method. This standard forms one of a series of BritishStandards for solvents and allied products. First issued in1934, it was revised in1951 and the present edition
11、has been prepared as the result of a review of the standard in the light of present-day requirements. The standard does not apply to material intended for medicinal use, which is included in the British Pharmacopia. The technical content of the standard is substantially unchanged, but specific gravi
12、ty limits at25/25 C have been introduced for use in tropical climates and a limit for water, determined by the Karl Fischer method, has been set. The opportunity has also been taken to clarify the wording of the standard and to bring it into line with current conventions. A British Standard does not
13、 purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside fr
14、ont cover, pagesi andii, pages1 to5 and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.BS579:1957 BSI 12-1999 1 1 Description BritishStandard diethyl ether (technical)
15、 shall be clear, colourless and free from matter in suspension, and shall consist essentially of diethyl ether, 1)C 2 H 5 OC 2 H 5 . 2 Specific gravity The specific gravity of the material at any one of the following temperatures shall be within the appropriate values as shown: 3 Distillation range
16、2) The material, on distillation in the manner described in Appendix A, shall yield at760mmHg pressure not less than95.0per cent by volume below36.0 C. 4 Water The material shall not contain more than1.0per cent by weight of water, determined in the manner described inBS2511 3) . 5 Residue on evapor
17、ation 2) The material shall not leave more than0.005per cent by weight of residue when tested in the manner described in Appendix B. 6 Acidity The material shall not contain more than0.002per cent by weight of acid, calculated as sulphuric acid, H 2 SO 4 , and determined in the manner described in A
18、ppendix C. 7 Peroxides 2) The material shall not show any peroxide when tested in the manner described in Appendix D. 8 Sulphur compounds The material shall not show any sulphur compounds when tested in the manner described in Appendix E. 9 Sample For the purpose of examination under this specificat
19、ion, a representative sample of the material measuring not less than half a litre shall be taken from an original and previously unopened container or from the bulk during packing, as may be arranged. The sample shall be placed in a clean, dry and air-tight glass-stoppered bottle of dark amber glass
20、 of such size that it is nearly filled by the sample. When it is necessary to seal the container, care shall be taken to avoid the risk of contaminating the contents in any way. 1) This name is approved by the International Union of Pure and Applied Chemistry. Temperature Specific gravity 15.5/15.5
21、C 20/20 C 25/25 C min. 0.719 0.714 0.709 max. 0.725 0.720 0.715 2) Owing to the inflammable nature of diethyl ether and its vapour, special care should be taken in performing the tests for distillation range and residue on evaporation. In rare cases, particularly where the material has been improper
22、ly stored, there may be an element of risk of explosion in carrying out the distillation and residue on evaporation tests, due to the presence of peroxides. It should always be ensured that peroxides are absent (see Appendix D) before commencing these determinations. 3) BS2511, “Determination of wat
23、er by the Karl Fischer method”.BS579:1957 2 BSI 12-1999 Appendix A Method for the determination of distillation range NOTEOwing to the inflammable nature of diethyl ether and its vapour, special care should be taken in carrying out this determination. In rare cases, particularly where the material h
24、as been improperly stored, there may be an element of risk of explosion in carrying out this test, due to the presence of peroxide. It should always be ensured that peroxides are absent (see Appendix D) before commencing this determination. Apparatus The apparatus required, part of which is shown in
25、 Figure 1, comprises: a) Distillation flask of100ml distillation capacity, complying with BS571 4) . b) Thermometer No. F50C/100, complying with BS593 5) . c) Draught screen, complying with BS658 6) , except that the shelf shall have a central circular hole60mm in diameter, the edge of which is beve
26、lled to fit the contours of the distillation flask. d) Water bath with a steam coil, electrical immersion heater or other suitable heating device for maintaining the temperature of the water, which is determined by means of a thermometer No.C100C/50 complying with BS593, fitted into that portion of
27、the shelf which forms the lid of the water bath. e) Receiver, Type1, of100ml capacity, complying with BS605 7) , closed with a plug of cotton wool. f) Condenser, Type3, complying with BS658, equipped with a suitable thermometer. Corrections to be applied to the specified distillation temperatures be
28、fore commencing the distillation 1) Read the barometer and apply the corrections as described in BS658. 2) When the corrected barometric pressure, p, deviates from760mmHg, add the correction0.037 (p 760) Centigrade degrees to the specified distillation temperatures. NOTEThis correction is valid only
29、 for pressures above700mmHg. 3) If the thermometer gives incorrect readings at the corrected specified distillation temperatures, further correct the latter by adding the amount of error if the thermometer is reading high, or subtracting the amount of error if the thermometer is reading low. Procedu
30、re Assemble the apparatus as described in BS658, filling the condenser cooling bath with water at a temperature of5 2 C and immersing the receiver up to the90ml mark in a bath of water maintained at the same temperature. Place the water bath on its support so that it is flush with the underside of t
31、he shelf of the draught screen and fill it to within( in. of the top with water at60 C. Measure in the receiver100ml of the diethyl ether previously brought to the temperature of the condenser water, transfer as completely as possible to the distillation flask and add a few pieces of clean, dry poro
32、us pot. Place the flask, thermometers and receiver in position, close the neck of the receiver with a plug of cotton wool and ensure, by addition of ice, that the condenser cooling bath remains at a temperature of5 2 C. Regulate the supply of heat to the water bath so that the temperature of the wat
33、er is maintained at60 2 C throughout the distillation. This should ensure a distillation rate of3 to4ml per minute. Read the volume of distillate in the receiver when the flask thermometer just reaches either, a. the corrected specified distillation temperature or, b. the maximum temperature of the
34、distillation, whichever is the lower. 4) BS571, “Flasks for the determination of distillation range”. 5) BS593, “Laboratory thermometers”. 6) BS658, “Apparatus for the determination of distillation range”. 7) BS605, “Distillation receivers (including Crow receivers)”.BS579:1957 BSI 12-1999 3 Figure
35、1 Assembly of distillation flask, draught screen and water bathBS579:1957 4 BSI 12-1999 Appendix B Method for the determination of residue on evaporation NOTEOwing to the inflammable nature of diethyl ether and its vapour, special care should be taken in carrying out this determination. In rare case
36、s, particularly where the material has been improperly stored, there may be an element of risk of explosion in carrying out this test, due to the presence of peroxides. It should always be ensured that peroxides are absent (see Appendix D) before commencing this determination. Procedure Evaporate100
37、ml of the diethyl ether to dryness in a weighed platinum, silica or borosilicate glass basin on a water bath. Dry the residue for30minutes in an oven at a temperature of100 2 C. Cool in a desiccator and weigh. Calculation Residue on evaporation, per cent by weight= where W=weight in grammes of resid
38、ue and S =specific gravity of the diethyl ether. Appendix C Method for the determination of acidity Reagents The reagents used shall be of recognized analytical reagent quality. The distilled water used shall be freshly boiled and cooled. a) Sodium hydroxide, 0.1N solution. b) Hydrochloric acid, 0.1
39、N solution. c) Methyl red indicator. Dissolve0.5g of water-soluble methyl red in1000ml of distilled water. Procedure Transfer50ml of the diethyl ether to a glass-stoppered separating funnel, add50ml of the distilled water and shake the liquids vigorously. After separation run the aqueous layer into
40、a receiver provided with a stopper. Repeat the shaking out with water twice, each time running the aqueous layer into the receiver already used. To the combined aqueous layers add0.2ml of the methyl red indicator and titrate with the sodium hydroxide solution, using a micro burette. Perform a blank
41、determination on150ml of the distilled water used, using the hydrochloric acid or the sodium hydroxide solution as appropriate. (Distilled water is usually alkaline to methyl red.) Calculation Acidity, expressed as sulphuric acid, Appendix D Method for the detection of peroxides Apparatus Stoppered
42、graduated cylinder, of10ml capacity, complying with BS604. 8) Reagent The reagent used shall be of recognized analytical reagent quality. Potassium iodide, 10per cent solution, freshly prepared. H 2 SO 4 , per cent by weight= where T 1 = volume in millilitres of0.1N sodium hydroxide solution used fo
43、r test, T 2 = volume in millilitres of0.1N hydrochloric acid used for blank, or T 3 = volume in millilitres of0.1N sodium hydroxide solution used for blank and S = specific gravity of the diethyl ether. 8) BS604, “Graduated measuring cylinders”. W S - 0.0098 T 1 T 2 T 3 +() S -BS579:1957 BSI 12-1999
44、 5 Procedure Transfer5ml of the diethyl ether to the cylinder and add the potassium iodide solution until the ether overflows. Shake vigorously and set aside in the dark for30minutes. Note if a yellow or brown coloration, indicating the presence of peroxides, develops in either layer. Appendix E Met
45、hod for the detection of sulphur compounds Reagents The reagents used shall be of recognized analytical reagent quality. a) Acetic acid, 10per cent. b) Mercury, clean, redistilled. Procedure To10ml of the diethyl ether contained in a glass-stoppered cylinder add1ml of the acetic acid and approximate
46、ly0.2ml of the mercury. Shake vigorously for one minute and then allow to stand for one hour. Note if a dark brown or black precipitate, indicating the presence of sulphur compounds, settles out at the ether-water interface.BS579:1957 BSI 389 Chiswick High Road London W4 4AL BSIBritishStandardsInsti
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