Metodos para determinar humedad

Application brochure

Mettler-Toledo GmbH CH-8606 Greifensee, Switzerland Tel. (01) 944 22 11, Fax (01) 944 30 60 Internet: http://www.mt.com UK Mettler-Toledo Ltd. 64 Boston Road, Beaumont Leys Leicester, LE4 1AW Tel. (0533) 357070 Fax (0533) 366399 Mettler-Toledo, Inc. Balances & Instruments 1900 Polaris Parkway Columbus, OH 43240, USA Tel. (614) 438 4511 Fax (614) 438 4900

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moisturecontent determination

Methods of moisture content determination Halogen Moisture Analyzer from METTLER TOLEDO

sFr. 12.–
Subject to technical changes © 02 / 2002 Mettler-Toledo GmbH Printed in Switzerland 11795011 MCG MarCom Greifensee Because We Care... This brochure is printed on recycled paper.

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Layout and contents of this brochure
This brochure is aimed at peoplewho are concerned with the determination of the moisture content of substances. It supports the reader in the selection of the most suitable measurement method. The brochure contains easily surveyed tables which can be used to quickly find solutions with the HR73 or HG53 Halogen Moisture Analyzer from METTLER TOLEDO. The first part of the brochure describes the principles of common moisturedetermination methods. The description of the strengths and weaknesses of the individual methods will support you in your evaluation of a suitable method. The second part is specially concerned with applications for the Halogen Moisture Analyzers from METTLER TOLEDO. Sampling, the sample preparation and optimum adaptation of the drying parameters to different types of problems are discussed. A number ofexamples show how to find optimal settings for the instrument. It is also explained how the moisture content measurement for a sample which has been determined by a reference method drying oven can be repeated much more quickly with a Halogen Moisture Analyzer. This chapter also contains several examples of applications developed at METTLER TOLEDO, as well as instructions for integrating theHalogen Moisture Analyzer into a computer environment. This second part deals particularly with the applicational aspects of the Halogen Moisture Analyzers from METTLER TOLEDO. Your local METTLER TOLEDO dealer will be pleased to advise you of other methods of determination.

Contents
1. 2. 2.1 2.2 2.3 2.4 2.5 2.6 2.7 3. 3.1 4. 5. 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 6. 7. 8. 9. Introduction Methods ofmoisture content determination Thermogravimetric methods Chemical methods Spectroscopic methods Other methods Tabulated overview of the methods for moisture determination Metrological terms Comparability of the methods The solutions available from METTLER TOLEDO The methods and the product line available from METTLER TOLEDO Description of the METTLER TOLEDO Halogen Moisture Analyzer Moisturecontent determination with the Halogen Moisture Analyzer The drying process Sampling and sample preparation Development of a method for the Halogen Moisture Analyzer Schematic procedure for developing a method Case study Obtaining results to match a reference method What if? Application examples Safety Ecology Quality systems References 4 8 10 16 17 21 25 26 28 29 29 31 34 34 35 40 50 51 53 57 58 62 6263 66

METTLER TOLEDO Application broschure Moisture content determination

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1. Introduction
What is moisture? There is no definition of general validity for the concept of moisture. In many cases, the physical measurement principle used for the moisture determination influences the definition. The following section describes moisture of the type occurring in connection with thermal(dry) determination methods. The moisture contained in a material comprises all those substances which vaporize on heating and lead to weight loss of the sample. The weight is determined by a balance and interpreted as the moisture content. According to this definition, moisture content includes not only water but also other mass losses such as evaporating organic solvents, alcohols, greases, oils,...