485190300026246 3812 International Standard 1388/12 (TSO 5-0 EthanolforindustrialuseMethodsoftest Part12:Determinationofpermanganatetime Ethanolausageindustriel-Methodesd'essai-Partie12:Déterminationdutempsdepermanganate Firstedition1981-12-01 ISO 1388/12-1981 (E) UDC661.722:543.8 Ref.No.ISO1388/12-1981(E) Descriptors : industrial products,ethanols,tests,determination,permanganates,time,potassium permanganate. Price based on 3 pages CoPYRIGHT 2ooo International Organization ForStandardization Information Handling Services,2oo0 48519030002625 1388P12-81 Foreword Iso (the International Organization for Standardization) is a worldwide federation of national standards institutes (ISo member bodies). The work of developing Inter- national Standards is carried out through ISo technical committees. Every member body interested in a subject for which a technical committee has been set up has the right to be represented on that committee.International organizations,governmental and non-governmental, in liaison with Iso, also take part in the work. Draft International Standards adopted by the technical committees are circulated to themember bodies for approval before their acceptance as International Standards by the ISo Council. International Standard ISo 1388/12 was developed by Technical Committee ISo/TC 47, Chemistry, and was circulated to the member bodies in February 1980. It has been approved by the member bodies of the following countries : Australia Germany, F.R. Romania Hungary South Africa, Rep. of Austria Belgium India Switzerland Brazil Italy Thailand Bulgaria Korea, Rep. of United Kingdom China Netherlands USSR Philippines Czechoslovakia France Poland No member body expressed disapproval of the document. This International Standard has also been approved bythe International Union of Pure and Applied Chemistry (IUPAC). International StandardsISo1388/1toISO1388/12canceland replaceISORecom- mendationR1388-1970,of whichtheyconstituteatechnical revision. ? International OrganizationforStandardization;1981 Printed in Switzerland CoPYRIGHT 2ooo International Organization For Standardization InformationHandlingServices,2ooo ISO1388/12-1981(E) INTERNATIONALSTANDARD 138P12-1 4851903 0002626 0 Ethanolforindustrialuse-Methodsoftest Part 12 : Determination of permanganate time Scopeandfieldof application Prepare this solution on the day of use. This part of ISo 1388 specifies a method for the determination of the permanganate time of ethanol for industrial use. 5 Apparatus This document should be read in conjunction with ISo 1388/1 (see the annex). Clean the glassware used so as to avoid any risk of con- tamination. Ordinary laboratory apparatus,and 2 Definition 5.1 -Water bath, capable of being controlled at 15 ± 0,2 °C. permanganate time : The number of minutes required, after adding 2 ml of o,2 g/l potassium permanganate solution to 5.2 Twomatched cylinders,of capacity 100ml,of 50 ml of the sample, for the colour to match that of a colour transparent and colourless glass, graduated at 50 ml and fitted standard. with ground glass stoppers. 5.3 Burette, of capacity 10 ml, graduated in 0,05 ml div- isions. Principle Addition to a test portion, under specified conditions, of potassium permanganate solution. Determination of the time 6 Procedure taken for the colour of this test solution to match that of a cobalt(ll) chloride and uranyl nitrate colour standard. 6.1 Testportion Carry out the test as soon as possible after receipt of the sam- ple. (lnstructions for the storage of the sample are specified in 4 Reagents ISO1388/1.) During the analysis, unless otherwise specified, use only Rinse one of the cylinders (5.2), first with 15 to 20 ml of reagents of recognized analytical grade, and distlled water or hydrochloric acid,Qapproximately 1,19 g/ml, about 38% water of equivalent purity. (m/m) solution, then six times with tap water, twice with distil- led water and finally with some of the laboratory sample. Immediately fill the cylinder