Permanganate index Fully automated determination according to DIN EN ISO 8467 (DIN 38409-5) • Economical: fully automated process reduces the time, reagents and personnel required • Reliable: reproducible results thanks to robust automation • Convenient: easy control and professional data handling with tiamo TM titration software 02 «Determining the permanganate index used to require considerable manual effort. Thanks to the automated Metrohm method manual work has been minimized and reproducibility and reliability of results has been increased.» David Welter, Teamleader sum parameters, SGS INSTITUT FRESENIUS Permanganate index − an important parameter in drinking water analysis The permanganate index is a sum parameter that indi­ For titrimetric determination, the water sample is heated cates the total load of organic and inorganic substances with a KMnO solution of known concentration and sul4 in drinking water. The substances concerned are mainly furic acid in a boiling water bath for 10 minutes. In the humic materials/acids that are formed primarily when process, some of the permanganate oxidizes the oxidizdead organic material in the soil breaks down and be able constituents in the water. The exact consumption of comes transformed. The permanganate index is used to permanganate is determined by adding an excess of so evaluate the quality of different types of water, e.g. drinkdium oxalate solution and then titrating the excess oxa ing water, mineral water, spring water, table water and late with permanganate solution. wastewater. It is determined in accordance with DIN EN ISO 8467 (DIN 38409­5). The challenge of sample preparation Sample transfer in external vessel ➡ 03 The determination of the permanganate index is a proce­ ➡ dure that is performed in a very large number of water Adding sulfuric acid and mixing laboratories, but it is not without snags. In particular, it is ➡ very difficult to carry out the time­critical heating of Heating of the sample samples manually in exactly the same way all the time if ➡ there is a high sample throughput. Addition of permanganate solution ➡ Efficient and reliable solution with the Metrohm 10 min reaction phase method ➡ The method developed by Metrohm solves this problem Addition of oxalate solution efficiently and reliably. The key lies in a heatable, external ➡ cell, with which the samples can be dealt with complet­ Titration of the excess oxalate ely automatically. Users need only to place the samples on the rack of the sample processor and start the system. Cleaning the titration vessel The transfer of the sample to the external titration cell and all the other sample preparation steps, in cluding the Chart 1: Steps in the fully automated determination of perman ganate heating of the sample, are performed automatically. (see Chart 1). Because of the clear database in tiamo TM users always have an overview of the situation. Control cards, filter Drinking water PMI [mg/L] and export functions and the freely definable layout of 1 0.39 the user interface make it possible to manage the data 2 0.39 comfortably and flexibly. 3 0.42 Mean value 0.40 s(abs) 0.017 s(rel) 4.33% Results of determiation of the permanganate index (PIM) of a drinking water Titration curve of the permanganate index determination of a drinking water Ordering information MATi 13: Completely automated permanganate index determination* * The thermostat for heating the external titration cell must be ordered separately. Details of the external titration cell in MATi 13 www.metrohm.com ­9100 Herisau G, CH ohm A witzerland by Metr , printed in S SW ­04 Subject to change Layout by Ecknauer+Schoch A 8.000.5065EN – 2012