【国外标准】 Standard Test Methods for Determination of Iron in Iron Ores and Related Materials by Dichromate Titrimetry

3.1 The determination of the total iron content is the primary means for establishing the commercial value of iron ores used in international trade.3.2 These test methods are intended as referee methods for the determination of iron in iron ores. It is assumed that all who use these test methods will be trained analysts capable of performing common laboratory procedures skillfully and safely. It is expected that work will be performed in a properly equipped laboratory and that proper waste disposal procedures will be followed. Appropriate quality control practices must be followed, such as those described in Guide E882.1.1 These test methods cover the determination of total iron in iron ores, concentrates, and agglomerates in the concentration range 30 % to 95 % iron.1.2 The test methods in this standard are contained in the sections indicated as follows:Test Method A— Iron by the Hydrogen Sulfide Reduction Dichromate Titration Method (30 % to 75 % Fe) Test Method B—Iron by the Stannous Chloride Reduction Dichromate Titration Method (35 % to 95 % Fe) Test Method C—Iron by the Silver Reduction Dichromate Titration Method (35 % to 95 % Fe)1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific hazards statements are given in Section 5 and in special “Warning” paragraphs throughout these test methods.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.