1、BRITISH STANDARD BS 4603:1970 Method for Determination of residue on ignition or ash of chemical productsBS4603:1970 This British Standard, having been endorsed by the Chairmanofthe Chemical Divisional Council, was publishedunder theauthority ofthe Executive Board on 30June1970 BSI 12-1999 The follo
2、wing BSI references relate to the work on this standard: Committee referencesC/40 andC/40/-/2 Draft for comment67/8193 ISBN 580 06250 3 Co-operating organizations The technical committee which has been working under the supervision of the Chemical Divisional Council, and which is responsible for the
3、 preparation of this British Standard, consists of members representing the following industry standards committees: Chemicals Laboratory Apparatus Pest Control Products Petroleum Pigments, Paints and Varnishes Tar Products (other than Ammonia) The committee entrusted with the preparation of this Br
4、itish Standard consists of members nominated by the technical committee. Amendments issued since publication Amd. No. Date CommentsBS4603:1970 BSI 12-1999 i Contents Page Co-operating organizations Inside front cover Foreword ii 1 Scope 1 2 Definition 1 3 Apparatus 1 4 Materials 1 5 Procedure 1 6 Ca
5、lculations 2 7 Test report 2 Table 1 Recommended vessels and conditions of test 3BS4603:1970 ii BSI 12-1999 Foreword This standard makes reference to the following British Standards: BS 805, Toluenes. BS 903, Methods of testing vulcanized rubber PartB13: Determination of ash and zinc oxide. BS 1416,
6、 Methods for the sampling and analysis of rennet casein. BS 1417, Methods for the sampling and analysis of acid casein. BS 1595, isoPropyl alcohol. BS 1741, The chemical analysis of liquid milk and cream. BS 1742, Methods for the chemical analysis of condensed milk. BS 1743, Methods for the chemical
7、 analysis of dried milk. BS 2869, Petroleum fuels for oil engines and burners. BS 3235, Test methods for bitumen. BS 3631, Method for the determination of the ash content of paper. BS 4113, Methods of test for sulphur. BS 4244, Porcelain and silica crucibles. BS 4450, Method for determination of ash
8、 from petroleum products. This British Standard has been prepared under the authority of the Chemical Divisional Council to provide a general method for the determination of residue on ignition or ash, applicable to a wide range of chemical products. It is hoped that this standard will provide a met
9、hod that can be adopted not only by those preparing British Standard specifications for products but also by other bodies preparing methods of test and product specifications, and that the method described in the standard can eventually be adopted to replace existing standard methods that differ in
10、detail. Various methods published by other standardization bodies and in appendices to British Standards have been considered and a general method has been provided specifying temperatures of ignition, type and size of vessel to be used for various groups of products. Determination of sulphated ash
11、has not been considered. The temperatures of ignition recommended for various types of product are wherever possible those agreed byISO/TC125 Enclosures and conditioning for testing (formerlyISO/ATCO), for inclusion in anISO draft proposal on a preferred series of temperatures. It has not been possi
12、ble to reduce the number of different temperatures specified for ignition because these are based on long established practices in the industries concerned. Nevertheless, it is hoped that as new methods and specifications are prepared for these various products it will be possible to reduce the numb
13、er of different temperatures specified. 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. S
14、ummary of pages This document comprises a front cover, an inside front cover, pagesi andii, pages1to4, 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 fron
15、t cover.BS4603:1970 BSI 12-1999 1 1 Scope This British Standard describes a method for the determination of residue on ignition or ash of chemical products. It is not suitable for samples producing ash that is fusible or volatile at the temperature of test, for which a sulphated ash procedure should
16、 be used. 2 Definition For the purposes of this British Standard the following definition applies: residue on ignition or ash the carbon-free residue resulting from ignition 3 Apparatus The following apparatus is required: 1) Electric muffle furnace capable of control to within 25degC of the require
17、d test temperature (seeTable 1). 2) Basins or crucibles of porcelain 1) , silica 1)or preferably platinum of suitable size. The following sizes are recommended: NOTE 1Platinum and platinum alloy vessels should not be used when the presence is suspected of lead, zinc, phosphates, or other substances
18、that attack platinum at high temperatures. Heating the vessel in the reducing flame of a Bunsen burner should be avoided, and platinum-tipped tongs should be used for handling the vessels when they are hot. NOTE 2For samples expected to produce less than0.1% of ash, platinum vessels should be used,
19、provided that lead or other substances liable to attack platinum are known to be absent. NOTE 3High results for ash are often obtained when substances containing phosphates are ashed in silica or porcelain vessels, owing to attack on the vessel. A suitable method for determining the ash of organic m
20、aterials containing phosphorus is to destroy the organic matter by wet oxidation (e.g.with nitric and sulphuric acids in a glass flask) and then to evaporate the solution and heat the residue to constant mass in a platinum vessel. Evaporation of the residual sulphuric or phosphoric acids and heating
21、 to constant mass might cause some attack on the platinum, but this is usually slight. 3) Desiccator of appropriate size, containing suitable desiccant (seeTable 1). 4 Materials The following materials are required with certain samples (see5.2, Notes1 and2). When used they shall be tested to ensure
22、freedom from ash: 1) Toluene complying with the requirements of BS805 2) . 2) isoPropyl alcohol, complying with the requirements of BS1595 3) . 3) Paraffin wax. 5 Procedure 5.1 According to the product to be tested (seeTable 1), select a suitable vessel from the list of recommended sizes given in3 2
23、). Heat the vessel inthe muffle furnace at the temperature of test for10-15minutes, allow it to cool sufficiently, transfer it to the desiccator and when cold weigh it to the nearest0.1mg. Weigh, to within1%, the quantity of sample required by the specification forthe product being tested (or if not
24、 specified, seeTable 1) into the vessel. 5.2 Ignite the sample or, if necessary, heat the vessel and its contents gently over a bunsen flame in a fume cupboard, and ignite any flammable vapours. CAUTION. When testing highly flammable or explosive liquids, add the sample to the vessel in small portio
25、ns, and burn each portion completely and cool the vessel before adding the next portion. NOTE 1The burning of some highly flammable materials can be moderated by the addition of molten paraffin wax. NOTE 2If the sample contains sufficient moisture to cause foaming and loss of material when heated, t
26、he test should be discontinued and repeated on a fresh sample to which1-2ml of99% isopropyl alcohol is added before heating. If this procedure does not give satisfactory results, add10-20ml of an equivolume mixture of ash-free toluene and isopropyl alcohol, to a fresh sample in a basin of125ml capac
27、ity, and mix thoroughly. Place several strips of ashless filter paper in the mixture and heat in a fume cupboard and ignite any flammable vapours. When the paper begins to burn the greater part of the water will have been removed. When determining very low ash values it may be necessary to carry out
28、 a blank determination with this solvent mixture. NOTE 3All fine powders should be heated very slowly to drive off initial gases including moisture. 1) SeeBS4244, “Porcelain and silica crucibles”. A. Porcelain or silica crucible 15ml or30ml nominal capacity, as required. B. Porcelain or silica basin
29、 50ml to120ml nominal capacity. C. Platinum crucible 15ml or30ml nominal capacity, as required. D. Platinum basin 50ml to120ml nominal capacity. 2) BS805, “Toluenes”. 3) BS1595, “isoPropyl alcohol”.BS4603:1970 2 BSI 12-1999 5.3 Continue heating until any vapours go on burning when the flame is withd
30、rawn, and allow the sample to burn itself out or to evaporate to a residue. When the sample burns itself out, and provided that it can be clearly seen that no undecomposed organic matter remains, the vessel should be heated gently over a bunsen burner until all organic matter has either been driven
31、off or been decomposed to carbon. It is important to see that the upper parts of the vessel are heated, otherwise a ring of undecomposed material may remain round the top of the vessel. Finally, ignite the residue in the muffle furnace at the temperature given inTable 1 until the ash is free from ca
32、rbon. NOTEIn testing foodstuffs, if the carbon formed is difficult to ignite the ash may be moistened with water, dried and re-ignited. 5.4 Allow the vessel to cool sufficiently, transfer it to the desiccator and, when cold, weigh it to the nearest0.1mg. Repeat the heating in the muffle furnace for1
33、5minute periods followed by cooling and weighing until two successive weighings do not differ by more than0.5mg. If the mass of ash obtained is greater than20mg, the determination should be repeated on a smaller portion of the sample. NOTEFor certain products the ashes of which are chemically reacti
34、ve or take up water preferentially,e.g.lime, the desiccant should be omitted. 6 Calculation Calculate the mass of the residue as a percentage by mass of the original sample from the following formula: 7 Test report Report the result as a percentage by mass or as required by the specification for the
35、 product being tested, indicating in the report the particular test conditions employed. where A=mass, in grammes, of residue found and M =mass, in grammes, of sample taken. 100A M -BS 4603:1970 BSI 12-1999 3 Table 1 Recommended vessels and conditions of test Reference should be made to the specific
36、ation for the product being tested, and where reference is made in this table to other British Standards, details specific to individual products or groups of products may be found therein. In the absence of such specific details, the table below may serve as a guide. Key to typeof vessel see3 2) fo
37、r further details: A Porcelain or silica crucible; B Porcelain or silica basin; C Platinum crucible; D Platinum basin. Type of product to be tested Vessel see32) and notesthereto Mass of sample Temperature of ignition Preferred desiccant g C Antifreeze solutions Bitumen (seeBS3235 a ) Carbon black D
38、 A(30ml), B(50ml) C(30ml) orD(50ml) A 20 Up to100g b 2 630 25 775 25 500 25 c none required anhydrous calcium chloride Cellulose acetate Cellulose acetate derivatives Cereal products Crude tar/refined tar/pitch Dairy products d Ethyl cellulose Extenders and pigments Fatty oils and fatty acids Fatty
39、quaternary ammonium chlorides General chemicals and rubber chemicals c Glycols and polyglycols A or C(200ml) D A (30ml silica) B or D C(30ml) A(silica) B B B or D B or D 10 10to50 2 10 2to5 2to5 20 20 5 100 600 15 500 25 500to630 800 25 500to550 900 25 1000 25 500to630 500 25 800 25 800 25 silica ge
40、l silica gelBS 4603:1970 4 BSI 12-1999 Table 1 Recommended vessels and conditions of test Type of product to be tested Vessel see32) and notesthereto Mass of sample Temperature of ignition Preferred desiccant g C Lac resin Lubricating grease Paper and board (see also BS3631 e ) Petroleum oils f Phar
41、maceutical products Pigments Protein products g Pyridine bases Rosin and tall oil Solvents Sulphur (seeBS4113 h ) Vulcanized rubber (seeBS903-B13 i ) A A A or C B or D B or D A A B D D B(silica) A(30ml silica) 2to5 2to5 1 Up to100 b 2to3 5 2to5 10 20 50 25 2 500 25 500 25 800 25 775 25 500 25 1000 2
42、5 500to550 630 25 500 25 630 25 850 50 600 25 none required a BS3235, “Test methods for bitumen”. b According to expected yield. c A temperature of up to950 C may be required for some types of carbon black, according to specification. d See alsoBS1741, “The chemical analysis of liquid milk and cream
43、”, BS1742, “Methods for the chemical analysis of condensed milk” andBS1743, “Methods for the chemical analysis of dried milk”. e BS3631, “Method for the determination of the ash content of paper”. f Distillate and residual fuel oils, crude oils, lubricating oils, waxes, and other petroleum products
44、free from ash-forming derivatives (seealso BS2869, “Petroleum fuels for oil engines and burners” and BS4450, “Method for determination of ash from petroleum products”). g See also BS1416, “Methods for the sampling and analysis of rennet casein” and BS1417, “Methods for the sampling and analysis of a
45、cid casein”. It may be necessary to add magnesium acetate to phosphoroproteins containing insufficient calcium or magnesium to bind the phosphorus. h BS4113, “Methods of test for sulphur”. i BS 903, “Methods of testing vulcanized rubber”, PartB13: “Determination of ash and zinc oxide”.BS4603:1970 BS
46、I 12-1999 British Standards The following are available on application: YEARBOOK Including subject index and numerical list of British Standards1. SECTIONAL LISTS.Gratis Acoustics (SL10) Aerospace materials and components (SL25) Automobile (SL34) British Standard Handbooks (SL27) Building (SL16) Che
47、mical engineering (SL5) Chemicals, fats, glues, oils, soap, etc. (SL4) Cinematography and photography (SL1) Coal, coke and colliery requisites (SL13) Codes of Practice (SL8) Consumer goods (SL3) Documentation, including Universal Decimal Classification (SL35) Drawing practice (SL37) Electrical engin
48、eering (SL26) Farming, dairying and allied interests (SL31) Furniture, bedding and furnishings (SL11) Gardening, horticulture and landscape work (SL41) Gas and solid fuel and refractories (SL2) Glassware, excluding laboratory apparatus (SL39) Heating, ventilating and air conditioning (SL42) Hospital
49、 equipment (SL18) Illumination and lighting fittings (SL14) Industrial instruments, etc. (SL17) Iron and steel (SL24) Laboratory apparatus (SL23) Leather, plastics, rubber (SL12) Local authority purchasing officers guide (SL28) Machine tools (SL20) Mechanical engineering (SL6) Nomenclature, symbols and abbreviations (SL29) Non-ferrous metals (SL19) Nuclear energy (SL36) Packaging and containers (SL15) Paints, varnishes, paint ingredients and colours for paints (SL9) Personal safety equipment (SL30) Pe
