BS-3108-1980.pdf
BRITISH STANDARD CONFIRMED JANUARY 1993 BS 3108:1980 Incorporating Amendment No. 1 Specification for Limestone for making colourless glasses UDC 666.123.32:622.355.11 Licensed Copy: sheffieldun sheffieldun, na, Wed Nov 29 08:09:18 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 3108:1980 This British Standard, having been prepared under the direction of the Laboratory Apparatus Standards Committee, was published under the authority of the Executive Board and comes into effect on 30 September 1980 © BSI 12-1999 First published March 1959 First revision September 1980 The following BSI references relate to the work on this standard: Committee reference LBC/32 Draft for comment 75/52658 DC ISBN 0 580 11395 7 Cooperating organizations The Laboratory Apparatus Standards Committee, under whose direction this British Standard was prepared, consists of representatives from the following Government departments and scientific and industrial organizations: Agricultural Research Council Association for Science Education British Educational Equipment Association British Laboratory Ware Association British Lampblown Scientific Glassware Manufacturers Association Ltd. British Pharmacopoeia Commission Chemical Industries Association Chemical Society Chemical Society, Analytical Division Department of Health and Social Security Department of Industry (Laboratory of the Government Chemist) Glass Manufacturers Federation Institute of Petroleum Ministry of Defence Pharmaceutical Society of Great Britain Scientific Instrument Manufacturers Association Society of Chemical Industry Society of Glass Technology* Standardization of Tar Products Tests Committee The organization marked with an asterisk in the above list was directly represented on the committee entrusted with the preparation of this British Standard. Amendments issued since publication Amd. No.Date of issueComments 3600April 1981Indicated by a sideline in the margin Licensed Copy: sheffieldun sheffieldun, na, Wed Nov 29 08:09:18 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 3108:1980 © BSI 12-1999i Contents Page Cooperating organizationsInside front cover Forewordii 1Scope1 2References1 3Sampling1 4Chemical composition1 Appendix A Method of inspection for contamination2 Appendix B Methods of sampling2 Appendix C Methods for the determination of chemical composition2 Appendix D Recommendations for the requirements to be agreed between the purchaser and supplier and recommended declarations to be made by the supplier8 Appendix E Determination of moisture content8 Appendix F Determination of size grading (sieve analysis)8 Publications referred toInside back cover Licensed Copy: sheffieldun sheffieldun, na, Wed Nov 29 08:09:18 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 3108:1980 ii © BSI 12-1999 Foreword This British Standard has been prepared under the direction of the laboratory Apparatus Standards Committee in close cooperation with the Society of Glass Technology (SGT). The Society of Glass Technology has been concerned for many years with the standardization of the methods of chemical analysis of glass and of the raw materials and refractories used in its manufacture. The Society published a specification for limestone for making colourless glasses in 19371), and revisions of the specification appeared in 19432), 19563) and 19724). The 1956 revision was used as the basis of the first edition of this British Standard, published in 1959, and the 1972 revision was used as the basis for the present British Standard. This British Standard supersedes BS 3108:1959, which is therefore withdrawn. The SGT specification includes general recommendations for the inspection of a sample of the limestone for obvious impurities such as magnetic materials or unusual mineral formations. No limits are specified for these items and they have therefore not been included as a mandatory part of the present standard; nevertheless, for the information of users, the inspection methods recommended by the SGT are given in Appendix A. Certain requirements for the composition of the limestone are not specified in this standard and are subject to agreement between purchaser and supplier; recommended agreements between purchaser and supplier for these requirements and recommended declarations by the supplier are given in Appendix D. 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 of pages This document comprises a front cover, an inside front cover, pages i and ii, pages 1 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. 1) J.Soc. Glass Tech., 21 (1937), 111 119. 2) ibid, 29 (1943), 140 149. 3) ibid, 40 (1956), 130 139. 4) Glass Technology, 13 (1972), 104 109. Licensed Copy: sheffieldun sheffieldun, na, Wed Nov 29 08:09:18 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 3108:1980 © BSI 12-19991 1 Scope This British Standard specifies the essential requirements and methods of test for limestone for making colourless glasses, i.e. glass that has no appreciable tint when viewed through the thickness normally encountered in practice. 2 References The titles of the publications referred to in this standard are listed on the inside back cover. 3 Sampling A representative sample of the material shall be obtained for each test by the appropriate method specified in Appendix B. 4 Chemical composition The chemical composition of the sample when analysed by the methods specified in Appendix C shall comply with the following requirements. a) The calcium content, expressed as calcium oxide (CaO), shall be not less than 55.2 %. NOTEThis is equivalent to a calcium carbonate content of 98.5 %. b) The total iron content, expressed as ferric oxide (Fe2O3), shall not exceed 0.035 %. c) The total non-volatile matter insoluble in hydrochloric acid shall not exceed 1.0 %. d) The organic matter shall not exceed 0.1 %. e) Colouring elements, other than iron, shall not be present to an extent sufficient to produce a colour in the glass. Licensed Copy: sheffieldun sheffieldun, na, Wed Nov 29 08:09:18 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 3108:1980 2 © BSI 12-1999 Appendix A Method of inspection for contamination A.1 Magnetic materials Dry, at a temperature of 100 °C, approximately 100 g of the 500 g sample prepared as described in B.2.1 and test with a magnet. Examine microscopically any magnetic material found, in order to differentiate between naturally occurring minerals and particles of metallic iron or scale acquired during crushing, handling or transport. A.2 Carbonaceous matter Dry, at a temperature of 110 °C, the remainder of the 500 g sample and inspect for unusual mineral formations and peaty or carbonaceous matter. Confirm the presence of any of these by microscopic examination. Appendix B Methods of sampling B.1 Sampling from bulk Take a representative sample of the bulk by a method previously agreed upon by the purchaser and supplier. NOTEThe recommended method is as follows. a) Collect a total mass of sample equal to 0.25 kg per 1 000 kg of the bulk, taking separate and approximately equal portions from at least 12 different places in the bulk; four from the top, four from the centre, and four from the bottom. b) Immediately mix thoroughly these separate portions constituting the sample, and pack immediately into containers5) so that the original condition is preserved until the sample is required for test. c) Ensure that the total mass of the sample is not less than 2 kg, and in the event of the bulk exceeding 10 000 kg, take a correspondingly large sample and reduce to a convenient size (2 kg) by an approved method agreed upon by purchaser and supplier. B.2 Sampling for tests Mix the contents of the containers holding the representative sample of the bulk and then spread the contents out in a layer and take the following samples. NOTESampling should be carried out with the aid of a thin-bladed spatula to avoid segregation of different particle sizes. B.2.1 Sample for inspection for contamination. Take at least 20 separate and approximately equal portions from different places to yield a total mass of approximately 500 g. The recommended method of inspection for contamination is given in Appendix A. B.2.2 Laboratory sample. Reduce the remainder of the representative sample (B.2) by mixing and quartering or with the aid of a sample divider, until a sample of approximately 1 kg is obtained. Spread this sample out in a layer and then take the following samples. B.2.2.1 Sample for moisture determination. Take at least ten separate and approximately equal portions from different parts to yield a total mass of approximately 50 g. Immediately determine the moisture content of this sample in accordance with the method specified in Appendix E. B.2.2.2 Sample for chemical analysis. Take at least ten separate and approximately equal portions from different parts to yield a total mass of approximately 50 g. Analyse this sample in accordance with the methods specified in Appendix C. B.2.2.3 Sample for size grading test. Take approximately equal portions from different parts to yield a total mass of at least 500 g. Test this sample for size grading in accordance with the method specified in Appendix F. Appendix C Methods for the determination of chemical composition C.1 General The constituents to be determined in the analysis of a limestone to be used for making colourless glasses are non-volatile matter including silica, aluminium oxide, total calcium expressed as calcium oxide, magnesium oxide, total iron expressed as ferric oxide, and organic matter. C.2 Reagents The following reagents are required. NOTE 1All reagents used should be free from such amounts of impurities as might endanger the accuracy of the determinations in question; analytical reagent quality will normally be suitable but provision should be made for blank determinations where these are considered to be essential. Water complying with the requirements of BS 3978 should be used throughout. NOTE 2The following designation is used for the solutions of acids and of ammonia. Concentrated reagents are specified, where necessary, in terms of percentage and the approximate normality in brackets. The diluted reagents are specified by giving the proportions by volume in which the appropriate concentrated reagent is to be diluted with water. Concentrated hydrochloric acid is described as hydrochloric acid 36 % m/m (11N) and hydrochloric acid 1 + 4 refers to the solution obtained by diluting one volume of hydrochloric acid 36 % m/m (11N) with four volumes of water. Solutions are aqueous unless otherwise stated. 5) Sealed plastics bags or glass jars fitted with non-metallic caps are suitable. If no determination of moisture is to be made, stout linen bags may be used. Licensed Copy: sheffieldun sheffieldun, na, Wed Nov 29 08:09:18 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 3108:1980 © BSI 12-19993 C.2.1 4-Nitrophenol indicator solution, 1 g/l. C.2.2 Calcium carbonate, dried at a temperature of 110 °C for 2 h and stored in a stoppered weighing bottle. C.2.3 Sodium carbonate, anhydrous. C.2.4 Chloroform, B.P. grade. C.2.5 Ethanol, 95 % V/V. C.2.6 Ammonia solution, concentrated, 35 % m/m (18N). C.2.7 Ammonia solution, diluted 1 + 1. C.2.8 Ammonia solution, diluted 1 + 3. C.2.9 Ammonium acetate buffer solution. Add, with stirring, 120 ml of glacial acetic acid to 500 ml of water, followed by 84 ml of ammonia solution (C.2.6). Cool, dilute to 1 litre and mix. C.2.10 Ammonium chloride/ammonia buffer solution. Make up the following two solutions: Mix solutions 1 and 2. C.2.11 Ammonium molybdate solution, 80 g/l. Dissolve 80 g of ammonium molybdate (NH4)6 Mo7O24.4H2O in water, filter if necessary, and dilute to 1 litre. Store in a polyethylene bottle. Discard after 4 weeks, or earlier if any appreciable deposit is observed. C.2.12 Ammonium nitrate solution, 20 g/l. Dissolve 20 g of ammonium nitrate in 1 litre of water, add a few drops of methyl red indicator (C.2.42) and add 1 + 1 ammonia solution (C.2.7) until the indicator just turns yellow. C.2.13 Bromine water, saturated solution. C.2.14 Calcium solution. Dissolve 10 g of calcium carbonate in 50 ml of the 1 + 1 hydrochloric acid (C.2.17), boil to eliminate CO2, cool and dilute with water to 1 litre. NOTE50 ml of calcium solution N 0.5 g CaCO3. C.2.15 Cupferron solution, 60 g/l. Dissolve 1.5 g of cupferron (see note) in 25 ml of water and filter if necessary. This solution shall be freshly prepared. NOTEIf the reagent is discoloured or gives a strongly coloured solution a new stock should be obtained. The solid reagent should be stored in a tightly stoppered bottle in the presence of a piece or pieces of ammonium carbonate to prevent decomposition. C.2.16 Hydrochloric acid solution, concentrated, 36 % m/m (11N). C.2.17 Hydrochloric acid solution, diluted 1 + 1. C.2.18 Hydrochloric acid solution, diluted 1 + 4. C.2.19 Hydrochloric acid solution,N. C.2.20 Hydrofluoric acid solution, 40 % m/m. C.2.21 Hydroxylammonium chloride solution, 200 g/l. C.2.22 Nitric acid solution, concentrated, 70 % m/m (16N). C.2.23 1,10-Phenanthroline hydrate solution, 1 g/l. Dissolve 1 g of the solid in the minimum volume of the 1 + 1 hydrochloric acid (C.2.17) and dilute with water to 1 litre. C.2.24 Sodium acetate buffer solution. Dissolve 54 g of hydrated sodium acetate in water, add 93 ml of glacial acetic acid and dilute to 1 litre. C.2.25 Sodium hydroxide solution, 5N. C.2.26 Sodium hydroxide solution,N. C.2.27 Sodium sulphate solution, 150 g/l. C.2.28 Sodium sulphate/ethanol wash solution. Dilute 10 ml of the sodium sulphate solution (C.2.27) to 90 ml with water, add 10 ml of ethanol and mix. C.2.29 Sulphuric acid solution, diluted 1 + 1. Add 500 ml of sulphuric acid, concentrated 98 % m/m (36N), to 500 ml of water, slowly, carefully and with stirring; much heat is evolved. C.2.30 Triethanolamine solution, diluted 3 + 7. C.2.31 Ethylenediamine-NNN½N½-tetra-acetic acid disodium salt dihydrate (EDTA), 50 g/l standard solution. Dissolve 50 g of EDTA in 1 litre of water, allow to stand overnight, and filter if necessary. Standardize as follows. Weigh out accurately, to the nearest 0.0002 g, approximately 0.5 g of calcium carbonate, dissolve in 5 ml of the 1 + 4 hydrochloric acid (C.2.18), dilute with water to about 50 ml, boil for a few minutes, and cool. Add 10 ml of triethanolamine (C.2.30), 5 ml of the 5N sodium hydroxide solution (C.2.25), 0.2 g of HSN indicator mixture (C.2.41) and titrate immediately with the EDTA solution to the blue end-point. Solution 1Add 67.5 g of ammonium chloride to 570 ml of the concentrated ammonia solution (C.2.6) a
