BS 4583-1991 Methods of test for higher alcohols for industrial use《工业用高级乙醇试验方法》.pdf

1、BRITISH STANDARD BS 4583:1991 Methods of test for Higher alcohols for industrial useBS4583:1991 This British Standard, having been prepared under the directionof the Chemicals Standards Policy Committee, waspublished under the authorityof the Standards Boardand comes into effect on 28June 1991 BSI 0

2、7-1999 First published March 1970 Second edition June 1991 The following BSI references relate to the work on this standard: Committee reference CIC/51 Draft for comment 90/56871 DC ISBN 0 580 19662 3 Committees responsible for this British Standard The preparation of this British Standard was entru

3、sted by the Chemicals Standards Policy Committee (CIC/-) to Technical Committee CIC/51, upon which the following bodies were represented: British Pharmacopoeia Commission British Society of Perfumers Chemical Industries Association Ministry of Defence Oil and Colour Chemists Association Royal Societ

4、y of Chemistry Solvents Industry Association Ltd. Amendments issued since publication Amd. No. Date CommentsBS4583:1991 BSI 07-1999 i Contents Page Committees responsible Inside front cover Foreword ii 1 Scope 1 2 Sampling 1 3 Measurement of colour 1 4 Determination of density at 20 C 1 5 Determinat

5、ion of distillation characteristics 1 6 Determination of water content 1 7 Determination of ash 1 8 Determination of acidity 1 9 Determination of aldehydes and ketones content 2 10 Measurement of colour after treatment with sulphuric acid 3 11 Determination of total alcohols content 4 12 Determinati

6、on of bromine number 5 13 Test reports 6 Appendix A Relationship between British Standards and international standards concerning methods of test for higher alcohols 7 Table 1 Mass of test portion for determination of total alcohols content 6 Table 2 Relationship between BS 4583 and international st

7、andards 7 Table 3 Relationship between British Standards and corresponding international standards concerning general test methods 7 Publication(s) referred to Inside back coverBS4583:1991 ii BSI 07-1999 Foreword This British Standard has been prepared under the direction of the Chemicals Standards

8、Policy Committee and provides a comprehensive series of test methods for C 6to C 13alcohols for industrial use. This revision supersedes BS4583:1970, which is withdrawn. The principal differences between this standard and the 1970 edition are as follows. a) The scope has been extended to include C 6

9、alcohols. b) General test methods are now specified for the measurement of colour (seeBS5339) and the determination of distillation characteristics (seeBS4591). c) For the determination of ash (seeclause 7), the heating in a furnace is carried out at a temperature of 600 30 C instead of 630 30 C. d)

10、 Acidity is now expressed as a percentage by mass of acetic acid instead of milliequivalents per kilogram. e) Aldehydes and ketones are now determined by titrating the liberated hydrochloric acid, from the reaction with hydroxylammonium chloride, with ethanolic potassium hydroxide solution (seeclaus

11、e 9). f) For the measurement of colour after treatment with sulphuric acid (seeclause 10), the reaction vessel is now cooled in an ice-water bath before, during and immediately after the addition of the sulphuric acid solution. g) For the determination of total alcohols content (seeclause 11), aceti

12、c anhydride is used for the esterification, instead of phthalic anhydride, and the results are now expressed as a percentage by mass. h) The determination of bromine number (seeclause 12) has been added. In preparing this standard, account has been taken of Parts 1 to 8 ofISO1843 “Higher alcohols fo

13、r industrial use Methods of test”, published by the International Organization for Standardization (ISO). Appendix A gives the relationship between international standards and this British Standard, together with the relationship between general test methods and corresponding international standards

14、. This standard describes methods of test only and should not be used or quoted as a specification defining limits of purity. Reference to this standard should indicate that the methods of test used are in accordance with the appropriate clauses of BS4583:1991. A British Standard does not purport to

15、 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 front cover,

16、pages i and ii, pages1 to 8, an inside back cover 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.BS4583:1991 BSI 07-1999 1 1 Scope This British Standard describes

17、methods for testingC 6to C 13alcohols for industrial use. NOTEThe titles of the publications referred to in this standard are listed on the inside back cover. 2 Sampling 1) Store the laboratory sample in a clean, dry and airtight, ground glass stoppered bottle, or a screw-capped bottle fitted with a

18、 polyethylene cone insert, of such capacity that it is almost filled by the sample. Sufficient ullage should be left in the bottle to avoid excessive pressure changes that could arise from temperature variations during storage and handling. About 10 % ullage is recommended. If it necessary to seal t

19、he bottle, take care to avoid any risk of contamination of the contents. Store the sample in a cool place in the dark. 3 Measurement of colour Determine the colour by the method described inBS5339. 4 Determination of density at 20 C Determine the density at 20 C by the method described inBS4522. 5 D

20、etermination of distillation characteristics Determine the distillation characteristics by the method described inBS4591, except that the following thermometer, distillation conditions and temperature corrections shall be used. a) Thermometer (see 5.1.2 of BS4591:1990). For measurement of distillati

21、on ranges not greater than 5 C, use a partial immersion thermometer, graduated at intervals of 0.2 C, complying with BS593 (e.g. a thermometer designated F200C/100). For measurement of distillation ranges greater than 5 C, use a thermometer designated F255C/100 complying with BS593. b) Distillation

22、(see 7.2 of BS4591:1990). Regulate the rate of heating so that the first drop of distillate falls from the end of the condenser after15min to 20min. c) Corrections to be applied to observed temperatures (see 9.1.2 of BS4591:1990). If the corrected barometric pressure deviates from101.3 kPa apply cor

23、rections to the observed temperatures by subtracting 0.038 C for every0.1 kPa above 101.3 kPa, or adding 0.038 C for every 0.1 kPa below 101.3 kPa. 6 Determination of water content Determine the water content by one of the methods described inBS2511. 7 Determination of ash 7.1 Principle A test porti

24、on is burned and then heated at a temperature of 600 30 C to constant mass. 7.2 Apparatus 7.2.1 Ordinary laboratory apparatus. 7.2.2 Platinum or silica dish. 7.2.3 Electric furnace, capable of being controlled at a temperature of 600 30 C. 7.3 Procedure 7.3.1 Test portion Weigh, to the nearest 0.1g,

25、 about 50g of the laboratory sample. 7.3.2 Determination In the dish (see7.2.2), previously heated at a temperature of 600 30 C, cooled in a desiccator and weighed to the nearest 0.0001 g, slowly burn the test portion (see7.3.1) in several portions. Heat finally in the furnace (see7.2.3), controlled

26、 at600 30 C, until all the carbonaceous matter has disappeared. Allow to cool in a desiccator and weigh to the nearest0.0001 g. Repeat the operations of heating, cooling and weighing until the difference in mass between two successive weighings does not exceed0.0005g. 7.4 Expression of results The a

27、sh A, expressed as a percentage by mass, is given by the equation: where m 0is the mass of the test portion (see7.3.1) (ing); m lis the mass of the residue (in g). 8 Determination of acidity 8.1 Principle The acidity in a test portion is titrated with a standard volumetric sodium hydroxide solution,

28、 in ethanolic medium, using phenolphthalein as indicator. 1) Detailed information on the sampling of liquid chemical products is given inBS5309-1 and BS5309-3. A 100 m 1 m 0 - =BS4583:1991 2 BSI 07-1999 8.2 Reagents 8.2.1 General. During the analysis, use only reagents of recognized analytical grade

29、, only methylated spirits complying with BS3591, and only water complying with grade3ofBS3978. 8.2.2 Ethanol, 95 % (V/V), or industrial methylated spirits, 95 % (V/V). NOTEThe use of industrial methylated spirits is governed by the Methylated Spirits Regulations, 1983(S.I.1983 No.252). It is not per

30、missible to use duty-free ethanol, received under the provisions of The Alcoholic Liquor Duties Act1979, Section10, for purposes for which industrial methylated spirits is an acceptable alternative. 8.2.3 Sodium hydroxide, standard volumetric solution, c(NaOH) = 0.1 mol/L. 8.2.4 Phenolphthalein, 5 g

31、/L ethanolic solution. Dissolve 0.5g of phenolphthalein in100mL of the ethanol or industrial methylated spirits (see8.2.2) and make faintly pink by the addition of dilute sodium hydroxide solution. 8.3 Apparatus 8.3.1 Ordinary laboratory apparatus. 8.3.2 Burette, of capacity 10mL, graduated in0.02mL

32、 divisions, complying with class A of BS846. 8.4 Procedure 8.4.1 Test portion Take 100mL of the laboratory sample by means of a pipette. 8.4.2 Determination Introduce 100mL of the ethanol or industrial methylated spirits (see8.2.2) into a 500mL conical flask, add 1mL of the phenolphthalein solution

33、(see8.2.4) and make faintly pink by the addition of the sodium hydroxide solution (see8.2.3). Add the test portion (see8.4.1) to the flask and titrate the mixture with the sodium hydroxide solution from the burette (see8.3.2), until the pink colour persists for 5 s. 8.5 Expression of results The aci

34、dity B, expressed as a percentage by mass of acetic acid (CH 3 COOH) per kilogram, is given by the equation: where Alternatively, the acidity C, expressed in terms of acid value, is given by the equation: NOTEThe “acid value” is the number of milligrams of potassium hydroxide required to neutralize

35、the acidity of 1g of the sample. 9 Determination of aldehydes and ketones content 9.1 Principle The carbonyl compounds present in a test portion are allowed to react with hydroxylammonium chloride to form an oxime. The liberated hydrochloric acid is titrated with a standard volumetric, ethanolic pot

36、assium hydroxide solution using a potentiometric method. 9.2 Reagents 9.2.1 General. During the analysis, use only reagents of recognized analytical grade and only water complying with grade3ofBS3978. 9.2.2 Ethanol, anhydrous. 9.2.3 Hydroxylammonium chloride, 10g/L ethanolic solution. Dissolve 50g o

37、f hydroxylammonium chloride (NH 2 OH.HCl) in90mL of water and dilute to1000mL with 95 % (V/V) ethanol. Further dilute100mL of this solution to 500mL with95%(V/V) ethanol. 9.2.4 Potassium hydroxide, standard volumetric solution in 95% (V/V) ethanol, c(KOH) = 0.1 mol/L; or 9.2.5 Potassium hydroxide, s

38、tandard volumetric solution in 95 % (V/V) ethanol, c(KOH) = 0.01 mol/L. 9.3 Apparatus 9.3.1 Ordinary laboratory apparatus. 9.3.2 Two conical flasks, of borosilicate glass, of capacity250mL, fitted with ground glass stoppers. 9.3.3 Two water-cooled reflux condensers, with ground glass joints to fit t

39、he flasks (see9.3.2). 9.3.4 pH meter, fitted with a glass measuring electrode and a calomel reference electrode. V is the volume of the sodium hydroxide solution (see8.2.3) used for the titration (in mL); is the density of the laboratory sample at20 C (determined by the method described in BS 4522)

40、(in g/mL); B 0.006V - = 0.006 is the mass of acetic acid corresponding to 1.00 mL of sodium hydroxide solution, c(NaOH) = 0.100 mol/L (in g). C 0.0561V - =BS4583:1991 BSI 07-1999 3 9.4 Procedure 9.4.1 Test portion Into one of the conical flasks (see9.3.2) already containing 10mL of the hydroxylammon

41、ium chloride solution (see9.2.3), weigh, to the nearest0.001g, 25g to 30g of the laboratory sample. 9.4.2 Blank test Carry out a blank test at the same time as the determination, following the same procedure but omitting the test portion. 9.4.3 Determination Add10mL of the ethanol (see9.2.2) to the

42、conical flask (see9.3.2) containing the test portion (see9.4.1). Attach one of the condensers (see9.3.3) to the flask and reflux for 30min on a boiling-water bath. Remove the flask, still carrying its condenser, from the boiling-water bath and allow to cool to ambient temperature. When cold, wash do

43、wn the inside of the condenser with 10mL of the ethanol. Transfer the contents of the flask quantitatively to a 250mL beaker, washing with 125mL of the ethanol. Titrate with the potassium hydroxide solution (see9.2.4) or, if greater precision is required, with the potassium hydroxide solution (see9.

44、2.5), using the pH meter (see9.3.4). The volume/potential graph may be plotted directly, in which case the point of inflection corresponds to the end-point of the titration (pH value about 3). Alternatively, the first derived curve may be plotted, in which case the end-point of the titration corresp

45、onds to the turning point of the curve. 9.5 Expression of results The aldehydes and ketones content D, expressed as a percentage by mass of carbonyl (CO), is given by the equation: where If the more dilute standard volumetric potassium hydroxide solution (see9.2.5) is used for the titrations, the eq

46、uation becomes: 10 Measurement of colour after treatment with sulphuric acid 10.1 Principle A test portion is treated with sulphuric acid solution, under specified conditions, and the colour developed is compared with that of a Hazen colour standard. 10.2 Reagents 10.2.1 General. During the analysis

47、, use only reagents of recognized analytical grade and only methylated spirits complying with BS3591. 10.2.2 Sulphuric acid solution, containing a minimum of 98 % (m/m) of sulphuric acid (H 2 SO 4 ). 10.2.3 Industrial methylated spirits, 95 % (V/V). NOTEThe use of industrial methylated spirits is go

48、verned by The Methylated Spirits Regulations, 1983(S.I.1983 No.252). It is not permissible to use duty-free ethanol, received under the provisions of The Alcoholic Liquor Duties Act1979, Section10, for purposes for which industrial methylated spirits is an acceptable alternative. 10.2.4 Water, compl

49、ying with grade3ofBS3978. 10.3 Apparatus 10.3.1 Ordinary laboratory apparatus. 10.3.2 Round-bottomed flask, of capacity 250mL, of borosilicate glass, fitted with a ground-glass stopper. 10.3.3 Burette, of capacity 10mL, complying with BS846, capable of delivering the sulphuric acid solution (see10.2.2) at the rate of two drops per second at ambient temperature. 10.3.4 Two matched Nessler cylinders, of capacity100mL. 10.3.5 Ice-water bath 10.3.6 Boiling-water bath, capa