Digestion method and detection method of iron ore

Abstract

The invention provides a digestion method and a detection method of iron ore. The digestion method comprises the following steps of: performing closed-vessel microwave-assisted digestion on iron ore samples mixed with hydrofluoric acid and sulfuric acid to form suspension; and heating the suspension in an opened system to perform digestion for the second time by using the residual sulfuric acid so as to obtain completely digested solution. The detection method comprises the step of detecting solution to be tested, which is prepared from the digested solution by a detection method such as inductive coupled plasma atomic emission spectroscopy so as to obtain the content of each element of the iron ore. The digestion method and the detection method have the characteristics of high efficiency, simpleness, quickness and accuracy; and particularly, the key elements, such as As, Pb, Zn, W, Sn, Ca, Mg, Cu, Co, Ni, Cr, Mo and the like, of the iron ore can be detected accurately, wherein the key elements can influence the quality of products prepared by the processes such as iron and steel smelting, vanadium extraction, titanium extraction and the like.

Description

technical field [0001] The invention relates to the technical field of analysis and detection of compounds, more specifically, to iron ore categories, especially to digestion methods and detection methods of various types of vanadium-ilmenite. Background technique [0002] Vanadium ilmenite (including raw ore, concentrate, tailings, sinter, pellet ore and oxidized ilmenite, etc. containing vanadium, titanium, and iron, hereinafter also referred to as vanadium ilmenite samples) is different from ordinary Iron ore, its composition and phase structure are very complex, and usually contains about 10% TiO 2 and a few percent of V 2 o 5 . For example, there are very rich vanadium-titanium magnetites in the Panxi region of my country. These vanadium-titanium magnetites are multi-element paragenetic ores with complex compositions and phase structures, and the composition of different ore sites is also quite different. In addition to containing major elements such as Fe, V, Ti, Si...

AI Technical Summary

Problems solved by technology

[0009] ① After microwave digestion, a suspension will be formed, and there are many residues in the suspension, which makes the digestion not thorough enough

Mainly reflected in two points: First, microwave digestion usually requires the use of hydrofluoric acid, however, the hydrofluoric acid remaining in the digestion solution will seriously corrode the detection instruments used in subsequent detection steps

If the detection instrument is replaced with special parts with anti-corrosion ability, it will usually reduce the important technical performance such as transmission atomization efficiency, and the method of reducing the corrosion of hydrofluoric acid by boric acid complexation will increase the types of salt in the solution to be tested , which makes the matrix of the solution to be tested more complex, which leads to more factors that interfere with the detection and affects the accuracy of the detection results; the second is that after microwave digestion, the high content of silicon in the vanadium ilmenite is not removed and remains in the solution , leading to an increase in the complexity of the matrix and the concentration of salts, thereby interfering with the accuracy of the detection of elements in vanadium-titanium-magnetite samples

[0011] ③In order to ensure safety, it is generally necessary to avoid the use of strong oxidizing perchloric acid, hydrogen peroxide and sulfuric acid reagents when digesting vanadium-titanite samples in a microwave sealed environment, which will lead to carbon and nitrogen in titano-magnetite samples. Compounds cannot be effectively decomposed, affecting the accuracy of test results

Microwave digestion generally does not use perchloric acid because of its strong oxidizing properties, and there is a risk of explosion when it reacts with certain substances; hydrogen peroxide is not used mainly because it is easy to decompose to generate oxygen, resulting in too high pressure in the tank; sulfuric acid is not used because of its high density, High viscosity will have matrix effect on subsequent instrument determination

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