1、BS EN ISO 20136:2017Leather Determinationof degradability by micro-organisms (ISO 20136:2017)BSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06BS EN ISO 20136:2017 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN ISO 20136:2017.The
2、UK participation in its preparation was entrusted to Technical Committee TCI/69, Footwear, leather and coated fabrics.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contr
3、act. Users are responsible for its correct application. The British Standards Institution 2017.Published by BSI Standards Limited 2017ISBN 978 0 580 89415 2 ICS 59.140.30 Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under the au
4、thority of the Standards Policy and Strategy Committee on 31 March 2017.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 20136 March 2017 ICS 59.140.30 English Version Leather - Determination of degradability by micro-
5、organisms (ISO 20136:2017) Cuir - Dtermination de la dgradabilit par les micro-organismes (ISO 20136:2017) Leder - Bestimmung der Abbaubarkeit durch Mikroorganismen (ISO 20136:2017) This European Standard was approved by CEN on 14 February 2017. CEN members are bound to comply with the CEN/CENELEC I
6、nternal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to
7、any CEN member. This European Standard exists in three official versions (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 CEN-CENELEC Management Centre has the same status as the official
8、 versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Nor
9、way, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2017 CEN All rights
10、 of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 20136:2017 EBS EN ISO 20136:2017EN ISO 20136:2017 (E) 3 European foreword This document (EN ISO 20136:2017) has been prepared by Technical Committee IULTCS “International Union of Leather Techn
11、ologists and Chemists Societies” in collaboration with Technical Committee CEN/TC 289 “Leather” the secretariat of which is held by UNI. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by September 2
12、017, and conflicting national standards shall be withdrawn at the latest by September 2017. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent ri
13、ghts. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, Franc
14、e, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 20136:2017 has been approved by CEN as
15、 EN ISO 20136:2017 without any modification. BS EN ISO 20136:2017ISO 20136:2017(E)IULTCS/IUC 37:2017(E)Foreword ivIntroduction v1 Scope . 12 Normative references 13 Terms and definitions . 14 Symbols and abbreviated terms . 25 Principle 25.1 Method A: assessment of biodegradation by manual titration
16、 . 25.2 Method B: assessment of biodegradation by infrared detection . 26 Chemicals . 37 Apparatus and materials 48 Procedure. 68.1 Collection and preparation of the inoculum 68.2 Preparation of the test material and reference material 68.3 Test conditions and incubation period. 68.4 Test equipment
17、. 68.4.1 Equipment for the assessment of biodegradation by manual titration (equipment A) 68.4.2 Equipment for the assessment of biodegradation by IR detection (equipment B) 78.5 End of the test 79 Quantification 89.1 Equipment for the assessment of biodegradation by manual titration (equipment A).
18、89.1.1 Determination of the organic carbon content 89.1.2 Determination of the amount of carbon dioxide produced (Method A) 89.1.3 Correcting for normality of HCl . 89.1.4 Percentage of biodegradation from carbon dioxide evolved . 89.2 Equipment for the assessment of biodegradation by IR detection (
19、Method B) . 89.2.1 Determination of the organic carbon content 89.2.2 Determination of the amount of carbon dioxide (CO2produced) 99.2.3 Percentage of biodegradation from CO2data . 910 Expression of results .1011 Validity of results 1012 Test report 10Annex A (informative) Determination of the degre
20、e and rate of degradation of the material .11Annex B (informative) Quantitative determination of leather biodegradation .16Bibliography .20 ISO 2017 All rights reserved iiiContents PageBS EN ISO 20136:2017ISO 20136:2017(E)ForewordISO (the International Organization for Standardization) is a worldwid
21、e federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that
22、 committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this docume
23、nt and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives
24、, Part 2 (see www .iso .org/ directives).Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the developme
25、nt of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www .iso .org/ patents).Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation on the voluntary nature
26、of standards, the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL: www .iso .org/ iso/ foreword .htmlThis docume
27、nt was prepared by the Chemical Tests Commission of the International Union of Leather Technologists and Chemists Societies (IUC Commission, IULTCS) in collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/TC 289, Leather, the secretariat of which is held by UNI
28、, in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).IULTCS, originally formed in 1897, is a world-wide organization of professional leather societies to further the advancement of leather science and technology. IULTCS has three Commissions, which are r
29、esponsible for establishing international method for the sampling and testing of leather. ISO recognizes IULTCS as an international standardizing body for the preparation of test methods for leather.IULTCS/IUC 37:2017(E)iv ISO 2017 All rights reservedBS EN ISO 20136:2017ISO 20136:2017(E)Introduction
30、One of the big problems faced by the footwear industry is waste treatment. Although this waste, especially in the case of leather, is not considered hazardous by current legislation, it is however produced in large quantities which present a problem for municipal landfill sites.The aim of the tannin
31、g process is to avoid skin putrefaction and increase the resistence of the obtained leather. For this purpose, chemical and biological agents are used which are involved in the denaturation and hardening of the main stromal protein, collagen, thus also producing physicochemical changes in the skin.T
32、here is a wide range of different agents used for leather tanning, which can be based on organic products, vegetable extracts or inorganic products, mostly metals.The most used tanning agent in the footwear industry is Chromium (III), which gives the skin desirable characteristics, such as elasticit
33、y, easy buffing and a good breathability and vapour permeability. However, the traditional tanning industry, and especially chrome tanning, generates wastes that pose an environmental threat. Also, chrome-tanned hides and skins have too long a lifespan, much larger than the useful life of the final
34、products. Therefore, the use of additives that are less harmful to the environment and which generate products that have a certain ease of degradation, once the material has achieved its purpose, would be preferred, thus minimising waste products.Within this sector, the development of fast biodegrad
35、ability quantification methods for leather that has been treated with alternative tanning agents is needed in order to predict whether these materials are more biodegradable than their predecessors. The methodology described in this document attempts to allow the completion of this form of analysis
36、in a test time of no more than 35 days.IULTCS/IUC 37:2017(E) ISO 2017 All rights reserved vBS EN ISO 20136:2017BS EN ISO 20136:2017Leather Determination of degradability by micro-organisms1 ScopeThis document specifies a test method to determine the degree and rate of aerobic biodegradation of hides
37、 and skins of different animal origin, whether they are tanned or not, through the indirect determination of CO2produced by the degradation of collagen.The test material is exposed to an inoculum (activated sludge from tannery wastewater) in an aqueous medium.The conditions established in this docum
38、ent correspond to optimum laboratory conditions to achieve the maximum level of biodegradation. However, they may not necessarily correspond to the optimum conditions or maximum level of biodegradation in the natural medium.In general, the experimental procedure covers the determination of the degra
39、dation degree and rate of the material under controlled conditions, which allows the analysis of the evolved carbon dioxide produced throughout the test. For this purpose, the testing equipment complies with strict requirements with regard to flow, temperature and agitation control.This method appli
40、es to the following materials: natural polymers of animal stroma (animal tissue/skins), animal hides and skins tanned (leather) using organic or inorganic tanning agents, leathers that, under testing conditions, do not inhibit the activity of microorganisms present in the inoculum.2 Normative refere
41、ncesThere are no normative references in this document.3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.ISO and IEC maintain terminological databases for use in standardization at the following addresses: IEC Electropedia: available at h t t p :/ ww
42、w .electropedia .org/ ISO Online browsing platform: available at h t t p :/ www .iso .org/ obp3.1filter pore no. 1diffuser with pore size from 100 microns to 160 micronsNote 1 to entry: This measurement is standard.3.2inoculumactivated sludge from tannery wastewaterINTERNATIONAL STANDARDISO 20136:20
43、17(E)IULTCS/IUC 37:2017(E) ISO 2017 All rights reserved 1BS EN ISO 20136:2017ISO 20136:2017(E)4 Symbols and abbreviated termsBa(OH)2 barium hydroxideC carbonCO2carbon dioxideGL18 threads are used with H-SA V40/45 Erlenmeyer flasks (5 000 ml volume)GL14 threads are used with H-SA V29/32 Erlenmeyer fl
44、asks (2 000 ml volume)H-SA V 29/32 inner and outer measures in millimetres of the orifice of the mouth of theErlenmeyer flasksH-SA V H40/45 inner and outer measures in millimetres of the orifice of the mouth of theErlenmeyer flasksIR infraredPSA pressure swing adsorption5 Principle5.1 Method A: asse
45、ssment of biodegradation by manual titrationThis test method determines the biodegradation percentage of tanned or untanned hides and skins through the indirect measurement of CO2evolved during the degradation of collagen, which is the major constituent of the skin, by the action of the microorganis
46、ms present in tannery wastewater.The CO2evolved during the test is indirectly determined through the reaction of Ba(OH)2 with CO2, which is precipitated as barium carbonate (BaCO3). The amount of CO2evolved is determined by titrating the remaining barium hydroxide with a 0,05 mol/l hydrochloric acid
47、 solution. These measurements are taken on a daily basis throughout the test.Biodegradability is assessed by indirectly measuring the CO2evolved as a function of time and calculating the biodegradation degree by the difference between the initial carbon percentage present in collagen and the remaini
48、ng soluble organic carbon content that has not been transformed into CO2in the course of the process.The initial carbon percentage (C) present in the collagen under study is determined by the elemental analysis of the test specimen. The biodegradation percentage does not include the amount of carbon
49、 transformed into a new cellular biomass that has not been metabolized to carbon dioxide throughout the test.The tests shall be carried out using equipment able to provide the conditions needed to carry out the test. Agitation, experiment temperature and CO2-free air inflow should be controlled.The test shall be carried out in duplicate in the presence of a positive control, which is made up of a synthetic medium, microorganisms and collagen, and a negative control, which is made up only of a synthetic medium and inoculum (activated sludge from
