Method for measuring total iron content in fly ash

Abstract

The invention provides a method for measuring total iron content in fly ash. The method comprises the steps that 1) a sample to be measured is weighed, concentrated hydrochloric acid, a sodium fluoride solution and a stannous chloride solution are added into the sample to be measured and are heated to dissolve the sample; 2) the stannous chloride solution is continuously dripped into the sample in the sample dissolving process until the test solution is faint yellow or colorless; 3) after the sample is dissolved completely, solid potassium permanganate is added into the sample, and the solution is boiled until the solution is reddish; 4) the stannous chloride solution is dripped into the test solution again to enable the test solution to return to be faint yellow, the volume of the solution is concentrated to be about 20mL, then 100mL of water is added into the solution, and the solution is cooled down; 5) sodium tungstate is used as an indicator, a titanium trichloride solution is dripped into the test solution to enable the test solution to return to be light blue, titration is immediately conducted by a potassium dichromate standard titration solution after the test solution is faded to be colorless from light blue, and the total iron content is computed according to the volume of wasted potassium dichromate standard titration solution. The method for measuring the total iron content in the fly ash eliminates interference of reducibility ions in the test solution, and improves accuracy.

Description

technical field [0001] The invention belongs to the technical field of chemical analysis, in particular to a method for measuring total iron content in dedusting ash. Background technique [0002] Ironmaking dust, also commonly known as blast furnace gas ash, is a product obtained by wet dust removal in the process of blast furnace smelting, along with the raw materials, fuel dust and particles produced by the intense reaction in the high temperature zone along with the blast furnace gas. Ironmaking dust contains a lot of elements such as iron and carbon, and has the characteristics of fine particles, many light substances, easy to disperse and lose, and difficult to store. Direct discharge not only wastes a lot of iron, carbon and other resources, but also causes serious environmental pollution. pollute. Therefore, the high-efficiency separation and recycling technology development of ironmaking dust as a secondary resource is of great significance to reduce environmental ...

AI Technical Summary

Problems solved by technology

The applicant once used the hydrochloric acid-sodium fluoride decomposition method in GB / T 6730.65-2009 for the determination of total iron in dust removal ash. This method is simple, easy to master, and has good accuracy and precision for iron ore inspection, but Since ironmaking dust is a by-product of dust removal in the blast furnace smelting process, its composition contains not only a large amount of elements such as iron and carbon, but also many reducing substances, which will consume a certain amount of heavy chromium Potassium acid standard titration solution makes the analysis result of total iron in the dust removal ash much higher during analysis, and the titration end point fades seriously, the color of the end point is difficult to observe, and the analysis precision is not good

Therefore, the existing GB / T 6730.65-2009 method cannot accurately determine the total iron content in ironmaking dust, and the measurement results are quite different from the real results