Classical Methods for the Characterization of Oils. Fats and Waxes by Saponification, Hydroxyl, Iodine and Acid Values 1983 Methods for the ExaminatiOnOf Waters and Associated Materials London Her Majesty's Stationery Office f3.20 net (This document contains 29 pages Classical Methods for the Characterization of Oils, Fats and Waxes by Saponification, Hydroxyl, Iodine and Acid Values 1983 Methods for the Examination of Waters and Associated Materials Contents Warning to Users 3 About this Series 5 A Introduction 6 Al General Explanation 6 A2 Sampling and Sample Preservation 6 A3 List of related British Standards 7 B Determinationof the SaponificationValue 8 BO Introduction 8 B! Performance Characteristics 8 B2 Principle 9 B3 Field of Application and Interferences 9 B4 Hazards 9 B5 Reagents 9 B6 Apparatus 10 B7 Analytical Procedure 10 C Determination of the Hydroxyl and Acetyl Values ii CO Introduction 11 Cl Performance Characteristics of the Method 11 C2 Principle 12 C3 Field of Application and Interferences 12 C4 Hazards 12 CS Reagents 12 C6 Apparatus 13 C7 Analytical Procedure 13 D Determination of the Iodine Value 15 DO Introduction 15 Dl Performance Characteristics of the Method 15 D2 Principle 16 D3 Application and Interferences 16 D4 Hazards 16 D5 Reagents 16: D6 Apparatus 17 D7 Analytical Procedure 17 E Determinationof the Acid Value 18 EO Introduction 18 El Performance Characteristics of the Method 18 E2 Principle 19 E3 Application and Interferences 19 E4 Hazards 19 E5 Reagents 19 E6 Apparatus 20 E7 Analytical Procedure 21 Sources of Error 23 Checking the Accuracyof Results 23 References 24 Some Typical Values of Oils and Fats which may be Encountered 24 Address for Correspondence 26 Membership responsible for this method 27 London Her Majesty's Stationery Office I I \ Warning to Users The analytical procedures given in this booklet should administration of the correct antidote can save life; but only be carried out by competent trained persons, with that incorrect treatment can make matters worse. It is adequate supervision when necessary. Local Safety suggestedthat both supervisorsand operators be familiar Regulations must be observed. Laboratory procedures with emergencyprocedures before starting even a slightly should be carried out only in properly equipped hazardous operation, and that doctors consulted after laboratories. Field operations should be conducted with any accident involving chemical contamination, due regard to possible local hazards, and portable safety ingestion, or inhalation, be made familiar with the equipment should be carried. Care should be taken chemical nature of the injury, as some chemical injuries against creating hazards. Lone working, whether in the require specialist treatment not normally encountered by laboratoryor field, should be discouraged. Reagents of most doctors. Similar warning should be given if a adequate purity must be used, along with properly biological or radio-chemical injury is suspected. Some maintained apparatus and equipment of correct very unusual parasites, viruses and other micro- specifications.Specifications for reagents, apparatus and organisms are occasionally encountered in samples and equipment are given in manufacturers' catalogues and when sampling in the field. In the latter case, all various published standards. If contamination is equipment including footwear should be disinfected by suspected, reagent purity should be checked before use. appropriate methods if contamination is suspected. There are numerous handbooks on first aid and The best safeguard is a thorough consideration ofhazards laboratorysafety. Among suchpublications are: 'Code of and the consequent safety precautions and remedieswell Practice for Chemical Laboratories' and 'Hazards in the in advance. Without intending to give a complete Chemical Laboratory' issued by the Royal Society of checklist, points that experience has shown are often Chemistry, London; 'Safety in Biological Laboratories' forgotten include: laboratory tidiness, stray radiation (Editors Hartree andBooth), BiochemicalSociety Special leaks (including ultra violet), use of correct protective Publication No 5, The Biochemical Society, London, clothing and goggles, removal of toxic fumes and wastes, which includesbiological hazards; and'The Prevention of containment in the event of breakage, access to taps, Laboratory Acquired Infection, 'Public Health escape routes, and the accessibility of the correct and Laboratory Service Monograph 6, HMSO, London. properly maintained first-aid, fire-fighting, and rescue Hazardous and solutions should Where the Committee have considered that a equipment. reagents special always be stored in and below face level. unusual hazard attention has been drawn to this in plain sight exists, Attention should also be to and the text so that additional care be taken given potentialvapour might beyond fire risks. Ifin it is safer to assume that the that which should be exercisedat all times when doubt, hazard carrying exist and take reasonable ratherthan to out analytical procedures. It cannot be too may precautions, strongly assume that no hazard exists until otherwise. emphasized that prompt first aid, decontamination, or proved © Crown copyright 1984 Firstpublished 1984 ISBN 0 11 751729 1 4 About this series This booklet is part of a series intended to provide both is the responsibility of the Standing Committee of recommended methods for the determination of water Analysts (to review Standard Methods for Quality quality, and in addition, short reviews of the more Controlof the WaterCycle). The Standing Committee of important analytical techniques of interest to the water Analysts is a committee of the Department of the and sewageindustries. In the past, the Department of the Environment set up in 1972. Currently it has seven Environment and its predecessors, in collaboration with Working Groups, each responsible for one section or various learned societies,have issued volumesof methods aspect of water cyclequality analysis. They are as follows: for the analysis of water and sewage culminating in 1.0 General principles of sampling and accuracy of 'Analysis of Raw, Potable and Waste Waters'. These results volumes inevitably took some years to prepare, so that 3.0 Empirical and physical methods theywere often partially out of date before they appeared 4.0 Metals and metalloids inprint. The present serieswill be published as individual 5.0 General nonmetallic substances methods, thus allowingfor the replacementor addition of 6.0 Organic impurities methods as quickly as possible without need to waiting 7.0 Biological methods for the next edition. The rate of publication will also be 9.0 Radiochemical methods related to the of for that urgency requirement particular The actual methods and reviews are produced by smaller method, tentative methods being issued when necessary. of in the under the and to date a panels experts appropriate field, The aim is to provide as complete up overall of the and and as is which supervision appropriate working group collection of methods reviews practicable, the main committee. The names of those associated with as far as take into account the will, possible, analytical this method are listed inside the back cover. Publication facilities available in different of the and parts Kingdom, of new or revised methods will be notified tothe technical the criteria of interest to those for the quality responsible whilst a list of Methods in Print is in the various of the water Becauseboth needsand press, given aspects cycle. current HMSO Sectional Publication List No 5. equipment vary widely, where necessary, a selection of methods may be recommendedfor a singledeterminand. Whilst an effort is made to prevent errors from occurring It will be the responsibility of the users — the senior in the published text, a few errors have been found in analytical chemist, biologist, bacteriologist etc. to decide booklets in this series. Correction notes and minor which of these methods to use for the determination in additions to published booklets not warranting a new hand. Whilst the attentionof the user is drawn to any booklet in this serieswill be issued periodicallyas the need special known hazards which may occur with the use of arises. Should anerror be found affecting the operation of any particular method, responsibility for proper amethod, the true sense not being obvious, or an errorin supervision and the provision of safe working conditions the printed text be discovered prior to sale, a separate must remain with the user. correction note will be issued for inclusion in that booklet. The preparationof this seriesand its continuous revision L R PITTWELL Secretary 31 October 1983 5 Classical Methods for the Characterization of Oils, Fats and Waxes by Saponification, Hydroxyl, Iodine and Acid Values A Introduction A.1 General A.l.1 These methods form part of a continuing serieswhich when complete can be used Explanation as part of a general co-ordinated scheme of analysis (see another publication in this series). A. 1.2 A sample of fat or oil may be characterized by gas chromatographic methods (see another publication in this series7)) as being of animal or vegetableorigin, but further complementary evidence might be required. It may also be classified as such a type of material by prior knowledge of the nature of the situation from which the sample was taken. The methods described in this publication provide the classical chemical information which may be used as the