Sample preparation method and detection method for water-soluble heavy metal elements in solid waste

Abstract

The invention specifically relates to a sample preparation method and detection method for water-soluble heavy metal elements in solid waste, belonging to the technical field of analytical chemistry. The method comprises the following steps: a, adding pure water into to-be-detected solid waste; b, adding a neutral oxidizing atmosphere protective agent and carrying out vibrating extraction for 4 to 6 h; c, carrying out filtering, taking filtrate and adding an oxidizing strong acid solution and the neutral oxidizing atmosphere protective agent into the filtrate so as to obtain a mixed solution; and d, maintaining the mixed solution in a sub-boiling state and then successively carrying out evaporative concentration, cooling to room temperature, dilution and volume fixation. The methods provided by the invention have the characteristics of easy operation, a few steps, low requirements on the performance of analysis equipment and experimental condition, small usage amounts of reagents, capacity of simultaneous determination of multiple elements, low quantitative determination lower limit, high precision, etc. and totally meet technical needs for accurate determination of water-soluble heavy metal elements like Hg, Cd, Pb, As, Se, Be, Cr, Cu, Zn and Ni in antimony titanium chloride tailings in an analysis laboratory with common equipment and conditions.

Description

technical field [0001] The invention belongs to the technical field of analytical chemistry, and in particular relates to a sample preparation method and detection method of trace or trace elements in solid waste, in particular to a sample preparation method and detection method of water-soluble heavy metal elements in tailings of titanium chloride extraction method. Background technique [0002] The titanium extraction process by the chloride method is the main technology for the production of titanium products. The key is to firstly mix the raw materials such as titanium concentrate and titanium slag with a carbon-containing reducing agent, and then carry out high-temperature smelting to reduce iron oxides to achieve separation of iron and titanium, and then through boiling chlorine Crude titanium tetrachloride is obtained by chemical and other treatment processes, and the refined titanium tetrachloride after purification and removal of impurities is used to manufacture sp...

AI Technical Summary

Problems solved by technology

The main technical shortcomings of the existing detection methods include: Although the technical performance indicators such as sensitivity and detection limit of the ICP-MS method are superior to the conventional ICP-OES method, the purchase price of the detection instrument is much higher than that of the ICP-OES method. , and its use cost and technical requirements for inspection conditions are relatively high, and it usually needs to be equipped with expensive special clean laboratories, as well as the maintenance of equipment and clean rooms, and the cost of parts such as sampling cones and consumables is very high. This has led to an increase in the cost of detection and analysis, which has affected the popularization of analytical methods

Ordinary laboratories that are not equipped with high-end instruments such as ICP-MS usually use the HG-AFS detection method to conduct Hg, Cd, Pb, As, Se, Zn and other harmful heavy metal elements that can produce hydride reactions with reducing agents such as potassium borohydride. Hydride reaction, the generated gas form of metal element hydrides such as mercury and plumbane is introduced into the atomic fluorescence spectrometer, and the harmful heavy metals such as Hg, Cd, Pb, As, Se, Zn are measured one by one. This method exists Determination of different elements requires different hydride reaction conditions, complex and cumbersome operation, large consumption of reagents, low efficiency of single element determination and long inspection period, especially the inability to determine non-hydride elements such as Be, Cr, Cu, Ni and other technical shortcomings

[0006] The ICP-OES technical means in the existing method is limited by the performance indicators such as the sensitivity of the analytical method, the detection limit, etc., and it is usually about 10 -5 ~10 -6 The lower limit of quantitative determination cannot meet the level requirement in titanium chloride tailings as low as 10 -8 The detection of trace levels of Hg, Cd, Pb, As, Se and other heavy metal elements requires

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