1、BRITISH STANDARD BS 1595-2: 1984 Propan-2-ol (isopropylalcohol) for industrial use Part 2: Methods of test UDC 661.725.3:543.062BS1595-2:1984 This British Standard, having been prepared under the directionof the Chemicals Standards Committee, was published under the authority ofthe Board of BSI and
2、comes intoeffect on 31October1984 BSI 09-1999 The following BSI references relate to the work on this standard: Committee reference CIC/4 Draft for comment80/55026 DC ISBN 0 580 14086 5 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Che
3、micals Standards Committee (CIC/-) to Technical Committee CIC/4 upon which the following bodies were represented: Chemical Industries Association Ministry of Defence Oil and Colour Chemists Association Royal Society of Chemistry Society of Chemical Industry The following bodies were also represented
4、 in the drafting of the standard, through subcommittees and panels: British Pharmacopoeia Commission British Society of Perfumers Cosmetic, Toiletry and Perfumery Association Limited Department of Trade and Industry (Laboratory of the Government Chemist) Amendments issued since publication Amd. No.
5、Date of issue CommentsBS1595-2:1984 BSI 09-1999 i Contents Page Committees responsible Inside front cover Foreword ii 1 Scope 1 2 Sampling 1 3 Determination of density at20 C 1 4 Determination of distillation characteristics 1 5 Determination of residue on evaporation on a water bath 1 6 Measurement
6、 of colour 1 7 Determination of water content 1 8 Determination of aldehydes and ketones content 1 9 Determination of acidity 2 10 Test for miscibility with water 3 11 Test reports 3 Publications referred to Inside back coverBS1595-2:1984 ii BSI 09-1999 Foreword This Part of this British Standard, w
7、hich has been prepared under the direction of the Chemicals Standards Committee, provides a comprehensive series of test methods for propan-2-ol for industrial use. Although applicable to the material in general, it includes all the test methods required to assess compliance with BS1595-1. The stand
8、ard previously numbered BS1595 (published in1965) has been amended to become BS1595-1 “Specification” and the methods of test that were included in the appendices have been deleted. In preparing this standard, the opportunity has been taken to implement Parts1, 2 and 3 of ISO756 “Propan-2-ol for ind
9、ustrial useMethods of test”, published by the International Organization for Standardization (ISO). These standards have been prepared, with the active participation of the UK, by Technical Committee47, Chemistry, of the International Organization for Standardization (ISO), as separate parts of ISO7
10、56 and constitute the revision of ISO Recommendation R756. Subsequent International Standards in the ISO756 series, if approved by the UK, will be published as additions to this BritishStandard, without technical alteration. Clauses2 to8 and clause11 of this British Standard are related to ISO756-1
11、but not equivalent in technical content. The technical differences occur in the method for the determination of aldehydes and ketones content (seeclause8): in this British Standard only one concentration of potassium hydroxide solution is allowed for the titration and only one form of expression of
12、the results (asapercentage by mass calculated as acetone) is given. ISO756-1 refers to the general method described in ISO1843-3 for the determination of aldehydes and ketones content, and gives the additional information needed to carry out the determination for propan-2-ol: in this British Standar
13、d, the method is described in full. Clause9 of this standard, which describes a method for the determination of acidity, is equivalent to ISO756-2 in technical content but differs in presentation. Clause10 of this standard, which describes a test for miscibility with water, is equivalent to ISO756-3
14、 in technical content but differs in presentation. This Part of this standard describes methods of test only and should not be referred to as a specification defining limits of purity. Reference to this Part of this standard should indicate that the methods of test used are in accordance with the ap
15、propriate clause(s) of BS1595-2. A British Standard does not 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
16、of pages This document comprises a front cover, an inside front cover, pagesi andii, pages1 to4, 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 cove
17、r.BS1595-2:1984 BSI 09-1999 1 1 Scope This Part of this British Standard describes methods for testing propan-2-ol 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 ai
18、rtight, ground glass stoppered bottle, or a screw-capped bottle fitted with a 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 stor
19、age and handling. About10% ullage is recommended. If it is necessary to seal the bottle, take care to avoid any risk of contamination of the contents. Store the sample in a cool place in the dark. 3 Determination of density at20 C Determine the density at20 C by the method described in BS4522. 4 Det
20、ermination of distillation characteristics Determine the distillation characteristics by the method described in BS4591, except that the following thermometer, temperature corrections and distillation conditions shall be used. a) Thermometer (3.2 of BS4591:1971). Use a thermometer designated F100C/1
21、00 complying with the requirements of BS593. b) Corrections to be applied to observed temperatures (7.2 of BS4591:1971). If the corrected barometric pressure deviates from1013mbar 2)apply a correction to the observed temperature by subtracting0.025 C for every millibar above, or adding0.025 C for ev
22、ery millibar below,1013mbar. c) Distillation (6.1 of BS4591:1971). Regulate the rate of heating so that the first drop of distillate falls from the end of the condenser after7to12min. 5 Determination of residue on evaporation on a water bath Determine the residue on evaporation by the method describ
23、ed in BS4524. 6 Measurement of colour Determine the colour by the method described inBS5339. 7 Determination of water content Determine the water content by one of the methods described in BS2511. 8 Determination of aldehydes and ketones content NOTEThis method is based on ISO1843-3 which is to be i
24、mplemented as part of the revision of BS4583:1970. 8.1 Principle Reaction of carbonyl compounds present in a test portion with hydroxylammonium chloride to form an oxime, and potentiometric titration of the hydrochloric acid liberated with standard volumetric ethanolic potassium hydroxide solution.
25、8.2 Reagents 8.2.1 General. During the analysis, use only reagents of recognized analytical grade and only water complying with BS3978. NOTEThe ethanol specified in 8.2.2 and 8.2.4 may be replaced for these purposes by industrial methylated spirits,95% (V/V) complying with BS3591. It should be noted
26、 that the use of industrial methylated spirits is governed 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 spiri
27、ts is an acceptable alternative to ethanol. 8.2.2 Hydroxylammonium chloride,10g/L ethanolic solution. Dissolve50g of hydroxylammonium chloride (NH 2 OH.HCl) in90mL of water and dilute to1000mL with95% (V/V) ethanol. Further dilute100mL of this solution to500mL with95% (V/V) ethanol. WARNING. Hydroxy
28、lammonium chloride is toxic, corrosive and an irritant. Avoid contact with eyes and skin. 1) Additional guidance is given in BS5309-1 and BS5309-3. 2) 1mbar=100N/m 2 =100Pa.BS1595-2:1984 2 BSI 09-1999 8.2.3 Ethanol, anhydrous, carbonyl-free, prepared as follows. Boil under reflux500mL of anhydrous e
29、thanol with5g of2,4-dinitrophenylhydrazine and5drops of hydrochloric acid solution, approximately1.19g/mL, for2 to3h. Distil off the ethanol slowly using a Widmer distillation column about300mm long and about25mm in diameter, or any other suitable column. Reject the first50mL of distillate and colle
30、ct the next400mL, rejecting the remainder. If the distillate is found to be coloured, carry out a redistillation. 8.2.4 Potassium hydroxide, standard volumetric solution in95% (V/V) ethanol, c (KOH)=0.1mol/L. 8.3 Apparatus 8.3.1 Ordinary laboratory apparatus 8.3.2 Two conical flasks, of borosilicate
31、 glass, of capacity250mL, fitted with ground glass stoppers. 8.3.3 Two water-cooled reflux condensers, with ground glass joints to fit the flasks(8.3.2). 8.3.4 pH meter, fitted with a glass measuring electrode and a calomel reference electrode. 8.4 Procedure 8.4.1 Test portion. Into one of the conic
32、al flasks(8.3.2) already containing10mL of the hydroxylammonium chloride solution(8.2.2) weigh, to the nearest0.001g,25g to30g of the laboratory sample. 8.4.2 Blank test. Carry out a blank test at the same time as the determination, following the same procedure but omitting the test portion. 8.4.3 D
33、etermination. Add10mL of the ethanol(8.2.3) to the conical flask (8.3.2) containing the test portion(8.4.1). Attach one of the condensers(8.3.3) to the flask and reflux for30min on a boiling water bath. Remove the flask, still carrying its condenser, from the boiling water bath and allow to cool to
34、ambient temperature. When cold, wash down the inside of the condenser with10mL of the ethanol. Transfer the contents of the flask quantitatively to a400mL beaker, washing with125mL of the ethanol. Titrate with the potassium hydroxide solution(8.2.4) using the pH meter(8.3.4). Thevolume/potential gra
35、ph may be plotted directly, in which case the point of inflection corresponds to the end-point of the titration (pH value about3). Alternatively, the first derived curve may be plotted, in which case the end-point of the titration corresponds to the turning point of the curve. 8.5 Expression of resu
36、lts The aldehydes and ketones content, expressed as a percentage by mass of acetone (CH 3 COCH 3 ), is given by the formula 9 Determination of acidity 9.1 Field of application This method is applicable to products having an acidity, expressed as acetic acid (CH 3 COOH), equal to or greater than0.000
37、6%(m/m). 9.2 Principle Dilution of a test portion with carbon dioxide-free water. Titration of the acidity with standard volumetric sodium hydroxide solution, in the presence of phenolphthalein as indicator. 9.3 Reagents 9.3.1 General. During the analysis, use only reagents of recognized analytical
38、grade and only carbon dioxide-free water recently prepared in accordance with9.3.2. 9.3.2 Water, carbon dioxide-free. Boil water, complying with BS3978, and allow it to cool in a flask fitted with a stopper carrying a soda-lime guard-tube. 9.3.3 Sodium hydroxide, standard volumetric solution, c(NaOH
39、)=0.1mol/L. 9.3.4 Phenolphthalein,5g/L ethanolic solution. Dissolve0.5g of phenolphthalein in100mL of95%(V/V) ethanol, and add the sodium hydroxide solution(9.3.3) until a pale pink colouration is obtained. NOTEThe ethanol may be replaced for this purpose by industrial methylated spirits,95% (V/V) c
40、omplying with BS3591. It should be noted that the use of industrial methylated spirits is governed 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 purpos
41、es for which industrial methylated spirits is an acceptable alternative to ethanol. where V 0 is the volume of the potassium hydroxide solution used for the blank test (in mL); V 1 is the volume of the potassium hydroxide solution used for the determination (in mL); m is the mass of the test portion
42、 (in g). 0.58 V 1 V 0 () m -BS1595-2:1984 BSI 09-1999 3 9.4 Apparatus 9.4.1 Ordinary laboratory apparatus 9.4.2 Conical flask, of borosilicate glass, of capacity500mL, fitted with a ground glass stopper carrying a soda-lime guard-tube. 9.4.3 Burette, of capacity10mL, graduated in0.02mL divisions, co
43、mplying with class A of BS846. 9.5 Procedure 9.5.1 Test portion. Take100 0.1mL of the laboratory sample at a temperature of about20 C. 9.5.2 Determination. Place100mL of the water(9.3.2) in the conical flask(9.4.2), add0.5mL of the phenolphthalein solution(9.3.4) and restore the pale pink colouratio
44、n by the addition of one drop of the sodium hydroxide solution(9.3.3). Add the test portion(9.5.1), and a further0.5mL of the phenolphthalein solution. Titrate the test solution with the sodium hydroxide solution(9.3.3), stoppering the flask and swirling its contents after each addition, until a pal
45、e pink coloration, persisting for about15s, is obtained. 9.6 Expression of results The acidity, expressed as a percentage by mass of acetic acid (CH 3 COOH), is given by the formula NOTEIf the standard volumetric solution used does not have the exact concentration stated in the list of reagents, an
46、appropriate correction should be applied. Report the result to two significant figures. 10 Test for miscibility with water 10.1 Principle Addition of water to a test portion, under specified conditions, and examination for any opalescence or turbidity. 10.2 Reagent During the test, use only water co
47、mplying with BS3978. 10.3 Apparatus 10.3.1 Ordinary laboratory apparatus 10.3.2 Two matched Nessler cylinders, of capacity100mL, similar in every respect, complying with BS612. 10.4 Procedure 10.4.1 Test portion. Take, by means of a safety pipette,5mL of the laboratory sample at a temperature of abo
48、ut20 C and introduce it into one of the Nessler cylinders(10.3.2). 10.4.2 Test. Add slowly, with thorough mixing,95mL of water to the test portion(10.4.1) in the Nessler cylinder. Examine for opalescence during the addition. Adjust the temperature of the mixture to20 C. Examine vertically for opales
49、cence or turbidity against a black background with side illumination, using as a standard the second Nessler cylinder containing100mL of water. 10.5 Expression of results Report the occurrence of opalescence or turbidity or whether the solution remained clear. 11 Test reports The test report, for each determination, should contain the following: a) an identification of the sample; b) a reference to the method used; c) the results, and the method of expression used; d) any unusual features noted during the determination; e) an
