1、DEUTSCHE NORM December 1998 I DIN Leather Determination of sulphated total ash and sulphated water-insoluble ash - IEN IS0 4047 (IS0 4047 : 1977) English version of DIN EN IS0 4047 ICs 59.140.30 Descriptors: Leather, chemical analysis, ash. Supersedes DIN 53305, December 1977 edition. Leder - Bestim
2、mung der sulfatierten Gesamtasche und der sulfatierten wasserunlslichen Asche (IS0 4047 : 1977) European Standard EN IS0 4047 : 1998 has the status of a DIN Standard. A comma is used as the decimal marker. National foreword This standard has been published in accordance with a decision taken by CEN/
3、TC 289 to adopt, without alteration, International Standard IS0 4047 as a European Standard. The responsible German body involved in its preparation was the Normenausschu Materialprfung (Mate- rials Testing Standards Committee), Technical Committee Chemische Prfverfahren fr Leder. DIN 53302-2 and DI
4、N EN IS0 4044 are the standards corresponding to International Standards IS0 2418 and IS0 4044, respectively, referred to in clause 2 of the EN. Amendments DIN 53305, December 1977 edition, has been superseded by the specifications of EN IS0 4047, which is identical to IS0 4047. Previous editions DI
5、N 53305: 1944-02, 1968-05, 1977-1 2. National Annex NA Standards referred to (and not included in References) DIN 53302-2 Leather - Laboratory sampling DIN EN IS0 4044 Leather - Preparation of chemical test samples (IS0 4044 : 1977) EN comprises 3 pages. No pari of this standard may be reproduced wi
6、thout the prior permission of Ref. No. DIN EN IS0 4047 : 1998-1 Y Deutsches Institut fr Normung e. V., Berlin. wth Verlag GmbH, D-10772 Berlin, has the exclusive right of sale for German Standards (DIN-Normen). English price group 05 Sales No. 1105 06.99 EUROPEAN STANDARD NORME EUFIOPEENNE EUROPISCH
7、E NORM EN IS0 4047 September 1998 ICs 59.140.30 Descriptors: Leather, chemical analysis, ash English version Leather Determination of sulphated total ash and sulphated water-insoluble ash (IS0 4047 : 1977) Cuir - Dosage des cendres sulfates totales et des cendres sulfates insolu- bles dans l?eau (IS
8、0 4047 : 1977) Leder - Bestimmung der sulfatierten Gesamtasche und der sulfatierten wasserunlslichen Asche (IS0 4047 : 1977) This European Standard was approved by CEN on 1998-08-09. CEN members are bound to comply with the CENKENELEC Internal Regulations which stipulate the conditions for giving th
9、is European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national stand- ards may be obtained on application to the Central Secretariat or to any CEN member. The European Standards exist in three official versions
10、(English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, the C
11、zech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, the Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, and the United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secre
12、tariat: rue de Stassart 36, B-1050 Brussels O 1998. CEN - All rights of exploitation in any form and by any means reserved worldwide for CEN national members. Ref. No. EN IS0 4047 : 1998 E Page 2 EN IS0 4047 : 1998 Foreword International Standard IS0 4047 : 1977 Leather - Determination of sulphated
13、total ash and sulphated water-insoluble ash, which was prepared by ISO/TC 120 Leather of the International Organization for Standardization, has been adopted by Technical Committee CEN/TC 289 Leather, the Secretariat of which is held by UNI, as a European Standard. This European Standard shall be gi
14、ven the status of a national standard, either by publication of an identical text or by endorsement, and conflicting national standards withdrawn, by March 1999 at the latest. In accordance with the CENKENELEC Internal Regulations, the national standards organizations of the follow- ing countries ar
15、e bound to implement this European Standard: Austria, Belgium, the Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, the Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, and the United Kingdom. Endorsement notice The text of the International S
16、tandard IS0 4047 : 1977 was approved by CEN as a European Standard without any modification. O INTRODUCTION The amount of mineral substances found by ashing leather may differ from the actual content owing to decomposition, reduction, or the escape by volatilization of certain salts. By treating the
17、 ash with sulphuric acid, the salts and oxides are converted into sulphates, but some salts will again be transformed into oxides at the selected temperature of ignition. To determine the total mineral content, for example within the framework of a complete leather analysis, the water- soluble and w
18、ater-insoluble inorganic substances can be ascertained by calculation or determined separately. Ammonium salts are not determined by this method (compare with IS0 4098). 1 This International Standard specifies a method for the determination of the sulphated total ash and the sulphated water-insolubl
19、e ash of leather. The method is applicable to all types of leather. The determination may be inaccurate by the extent to which the leather contains organo-metallic compounds, for example silicone (see note 1 in 8.1 1. SCOPE AND FIELD OF APPLICATION 2 REFERENCES IS0 2418, Leather - Laboratory samples
20、 - Location and identification. IS0 2588. Leather - Sampling - Number of items for a gross sample. IS0 4044, Leather- Preparation of chemical test samples. ) IS0 4098, Leather - Determination of water-soluble matter, water-soluble inorganic matter and water-soluble organic matter. 3 DEFINITIONS For
21、the purposes of this International Standard, the following definitions apply : 3.1 sulphated total ash : The residue obtained from carbonized leather at 800 OC after sulphating the ash under the specified conditions. 3.2 sulphated water-insoluble ash : The residue obtained when leather, previously e
22、xtracted with water as specified in IS0 4098, is carbonized after sulphating the ash under the specified conditions. 4 PRINCIPLE Carbonization of the leather followed by treatment with sulphuric acid and aching in an open crucible. 5 REAGENTS During the analysis, use only reagents of recognized anal
23、ytical grade and only distilled water or water of equivalent purity. 5.1 Sulphuric acid, approximately 2 N solution. 5.2 Ammonium nitrate, approximately 100 g/I solution. 6 APPARATUS Ordinary laboratory apparatus and in particular 6.1 Crucibles and dishes of glazed porcelain, platinum or quartz. 6.2
24、 Muffle furnace, capable of being maintained at a temperature close to, but not exceeding, 800 OC (see note 4 in 8.1). 1) At present at the stage of draft. Page 3 EN IS0 4047 : 1998 7 SAMPLING 7.1 Whole pieces of leather In the absence of any other agreement on sampling between the interested partie
25、s, the procedure specified in IS0 2588 for sampling from a lot shall be followed. Samples shall be taken from the pieces as specified in IS0 2418. 7.2 Other applications Sampling shall be carried out as required by the relevant specification or contract. 8 PROCEDURE 8.1 Sulphated total ash Prepare t
26、he sample as specified in IS0 4044 (see note 1). Weigh, to the nearest 0,001 g, 2 to 5 g of the sample and carefully carbonize it over a low flame in a crucible (6.1) which has been previously heated to 8OO0C, cooled and weighed, so that the leather burns with a small flame. Carbonize fat-liquored l
27、eather particularly carefully so that the grease burns very slowly. Then thoroughly moisten with the sulphuric acid solution (5.1) and heat over a low flame until sulphur trioxide fumes are no longer visible. Heat more vigorously, and then ignite in the furnace (6.2). maintained at 800 “C. until com
28、pletely ashed (see notes 2, 3 and 4). Cool in a desiccator and weigh. Repeat the addition of acid and the heating, cooling and weighing operations until the mass of the residue is constant (see note 51. NOTES 1 It is advisable to extract leather impregnated with volatile organo-metallic compounds wi
29、th dichloromethane before deter- mining the sulphated total ash. 2 If a carbon-free residue cannot be obtained in spite of heating at 800 “C. the residue should be moistened with a little ammonium nitrate solution (5.2) and the heating repeated until the ash is free from carbon. 3 If complete ashing
30、 is not possible, even with the aid of ammonium nitrate, extract the contents of the crucible with hot water and filter through an ash-free filter paper. Ash the carbon residue together with the filter paper, add the filtrate to the contents of the crucible, evaporate on a water bath, again heat at
31、800 “C until the last traces of visible carbon are removed, cool in a desiccator and weigh. 4 At temperatures above 800“C, some loss of mass from the residue is possible due to volatilization of certain inorganic salts. For this reason, close control is essential to prevent the maximum furnace tempe
32、rature from exceeding 800 “C. 5 The sulphated total ash should be retained, if required for the determination of its components (for example chromic oxide, aluminium oxide, iron oxide) and for the determination of the cations present in the mineral impurities. 8.2 Sulphated water-insoluble ash Extra
33、ct the water-soluble substances from the prepared ground leather as specified in ISO4098. Air-dry the extracted sample (see note). Continue as specified in 8.1. NOTE - For the separate determination of sulphated water- insoluble ash, it is not absolutely necessary for the whole of the extracted and
34、dried leather left after determination of the water- soluble matter, in accordance with IC0 4098, to be ashed. The residual air-dried leather can be mixed and weighed and an adequate part of it ashed. 9 EXPRESSION OF RESULTS 9.1 Calculation 9.1.1 The sulphated total ash is given, as a percentage by
35、mass, by the formula m1 -x 100 mo where mo leather; m, is the mass, in grams, of sulphated total ash. is the mass, in grams, of the original sample of 9.2.1 The sulphated water-insoluble ash is given, as a percentage by mass, by the formula m2 -x 100 m0 where mo leather; m2 is the mass, in grams, of
36、 the sulphated water- insoluble ash. is the mass, in grams, of the original sample of NOTE - The percentage of sulphated water-insoluble ash may alternatively be calculated by deducting from the percentage of total sulphated ash the percentage of sulphated ash from the water- soluble matter, if this
37、 has been separately determined. 9.2 Repeatability The results of duplicate determinations by the same operator should not differ by more than 0,l %, calculated on the original sample mass. If the difference is greater, the determination shall be carried out once more. 10 TEST REPORT The test report shall include the following particulars : a) a reference to this International Standard; b) complete identification of the sample; c) the results obtained, to one decimal place, and the mean value; d) details of any special circumstances which may have affected the results.
