Determination method of trace ions in chromium salt

Abstract

Provided is a determination method for trace ions in chromium salt. The method comprises the following steps: an industrial chromium salt solution is provided; the pH value of the industrial chromium salt solution is adjusted to be between 8-10, and the existence forms of chromium are all chromates; chromate precipitating agents are added in the industrial chromium salt solution to change all the chromates in the industrial chromium salt solution into precipitation; the solution with precipitation is separated into precipitation and a filter liquid; the precipitation is fully washed by utilization of hot water and the washing liquid is collected; the filter liquid and the washing liquid are mixed, and the content of the trace ions in the mixed liquid of the filter liquid and the washing liquid is determined by utilization of ICP.

Description

technical field [0001] The invention relates to a method for measuring trace components in solutions, in particular to a method for measuring trace ions in chromium salts. Background technique [0002] Industrial sodium chromate solution usually comes from chromite roasting, leaching, and filtration processes. Compared with the sodium chromate solution prepared by reagents, its composition contains higher diagenetic elements and other elements introduced in the process, and its purity is poor. . According to preliminary analysis and judgment, industrial sodium chromate solution contains iron, calcium, magnesium, potassium, lead, aluminum, strontium, vanadium, manganese, silicon, chlorine, sulfur, hydroxide, carbon and other trace or trace impurity elements . [0003] The national standard for industrial potassium dichromate GB1611-92 only limits the content requirements of sulfate and chloride; in the chemical industry standard HG / T3439-2000 for potassium dichromate reagen...

AI Technical Summary

Problems solved by technology

However, the direct use of ICP to determine the trace components in the chromate system has the following disadvantages: (1) The spectral interference of hexavalent chromium is strong, resulting in a huge deviation in the measurement data under each characteristic line of the same element, and the accuracy of the data is poor ; (2) There is a contradiction between the dilution factor of the sample and the determination range of trace components

The greater the dilution factor, the more stable the working conditions of the instrument, but the lower the content of trace components, it is not easy to detect; the smaller the dilution factor, the higher the content of trace components, but the unstable working conditions of the instrument (shown that the working pressure is easy to rise), Poor test result stability

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