6333 (ISO International Standard Water quality - Determination of manganese Formaldoxime spectrometric method Qualite de I'eau - Dosage du manganese - Méthode spectrometrique a la formaldoxime First edition - 1986-03-15 Corrected and reprinted - 1986-07-15 UDC 543.33 : 543.42 Ref. No. 1SO 6333-1986 (E) Descriptors : water, quality, chemical analysis, determination of content, manganese, spectrophotometric analysis. Price based on 4 pages Copyright International Organization for Standardization ed without license from IHS Not for Resale Foreword IsO (the International Organization for Standardization) is a worldwide 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 committee. International organizations, govern- mental and non-governmental, in liaison with IsO, also take part in the work. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the ISo Council. They are approved in accordance with IsO procedures requiring at least 75 % approval by the member bodies voting. International Standard ISO 6333 was prepared by Technical Committee ISO/TC 147, Water quality. Users should note that all International Standards undergo revision from time to time and that any reference made herein to any other International Standard implies its latest edition, unless otherwise stated. International Organization for Standardization, 1986 ? Printed in Switzerland itted without license from IHS Not for Resale ISO 6333-1986 (E) INTERNATIONAL STANDARD Water quality Determination of manganese Formaldoxime spectrometric method 0 Introduction Care must be taken to avoid ingestion or inhalation of vapours and to protect the hands, eyes and face. Gloves In water containing oxygen, most of the manganese will be and goggles must be worn and any suspected skin con- present as undissolved forms, often associated with micro- tamination washed off immediately. Inhalation of the organisms and as complexes with, for example, humic acid. If vapours of formaldehyde and formaldoxime will result in the water is free of oxygen or strongly acidic, all manganese severe irritation and oedema of the upper respiratory will be present in dissolved forms. tract. During the analysis, use only reagents of recognized analytical grade, and only deionized water or water distilled from an all- Scope and field of application glass apparatus with a manganese content that is as low as possible. This International Standard specifies a formaldoxime spec- trometric method for the determination of total manganese (including dissolved, suspended and organically bound Oxidizing reagent. 3.1 manganese) in surface and drinking water. Either potassium peroxodisulfate (K,S20g) or sodium peroxo- The method is applicable to the determination of manganese disulfate (Na2S20g). concentrations between 0,01 mg/l and 5 mg/l. Manganese concentrations above 5 mg/l may be determined after suitable 3.2 Sodium sulfite (Na,sO3), anhydrous. dilution of the sample. For known possible interferences, see clause 8. 3.3 EDTA, tetrasodium salt, solution, c(EDTA) = 0,24 mol/l. NOTE -- This method is not applicable to highly contaminated waters such as industrial waste water. Dissolve 90 g of disodium ethylenedinitrilotetraacetic acid (NazEDTA) dihydrate (C1oH14N,Na2Og:2H20) and 19 g of sodium hydroxide (NaOH) in water and dilute to 1 000 ml. 2 Principle Alternatively, dissolve 109 g of tetrasodium ethylenedinitrilotetra- acetic acid (NagEDTA) tetrahydrate (C1oH12N2Na4Og:4H2O) or Addition of a formaldoxime solution to a test portion and spec- 100 g of tetrasodium ethylenedinitrilotetraacetic acid dihydrate trometric measurement of the orange-red complex