Method for rapid determination of gold in copper concentrate powder

Abstract

The invention belongs to the technical field of precious metal test and analysis and relates to a method for rapid determination of gold in copper concentrate powder. The method comprises sintering a copper concentrate powder sample at a high temperature, dissolving the copper concentrate powder sample in aqua regia to obtain a solution to be detected, wherein a dissolution rate of the coexisting elements in aqua regia dissolution is low, feeding gold in a form of a chlorine complex ion into the solution, filtering the solution, and determining the gold amount through a continuous light source flame atomic absorption spectrophotometer. The method eliminates the interference of coexisting elements and improves determination sensitivity, realizes accurate and rapid direct determination of gold in copper concentrate powder through a flame atomic absorption method, is finished in 4h, can be simply and fast operated, utilizes a small amount of a regent and greatly reduces a detection cost.

Description

technical field [0001] The invention belongs to the technical field of precious metal testing and analysis, and relates to a rapid determination method for gold in copper fine powder. Background technique [0002] The content of gold in the copper concentrate is ppm level, and there are high iron, copper and other elements in the material, usually 10% of the gold content. 6 -10 7 When using conventional atomic absorption spectrometry to determine gold, due to the limited wavelength resolution of ordinary atomic absorption, generally around 0.2nm, the coexisting components are prone to spectral interference, and the spectral lines of elements such as iron are more complex, and spectral interference more serious. [0003] When the sensitive line 242.795nm of gold is used to measure gold, the spectral lines of coexisting elements in the instrument resolution range of 0.2nm are Fe242.950nm, Fe242.981nm, Fe242.910nm, Fe242.904nm, Cu242.891nm, Pb242.864nm , Ag242.963nm, etc., t...

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Problems solved by technology

[0002] The gold content in the copper concentrate powder is at the ppm level, and there are relatively high iron, copper and other elements in the material, usually 10% of the gold content. 6 -10 7 When using conventional atomic absorption spectroscopic analysis method to determine gold, due to the limited wavelength resolution of ordinary atomic absorption, generally around 0.2nm, the coexisting components are easy to produce spectral interference, and the spectral lines of elements such as iron are more complex, spectral interference more serious

[0003] When the gold sensitive line 242.795nm is used to measure gold, the spectral lines of coexisting elements within the range of instrument resolution 0.2nm are Fe242.950nm, Fe242.981nm, Fe242.910nm, Fe242.904nm, Cu242.891nm, Pb242.864nm , Ag242.963nm, etc. These coexisting elements will contribute to the absorption intensity of gold, that is, spectral interference, which is also the main interference factor in the determination of gold by ordinary atomic absorption spectrometry; at the same time, the gold content in copper concentrate powder is very low, it must be A sufficient amount of sample must be weighed in order to have a signal intensity that meets the measurement requirements on the atomic absorption spectrometer, but as the amount of sample increases, the amount of coexisting interfering elements also increases, and the spectral interference is more serious, so , it is difficult to directly determine the gold content in copper fine powder by atomic absorption method

[0004] The detection limit of gold at 242.795nm by ordinary flame atomic absorption spectrometer is 0.01μg / mL, and the sensitivity is about 0.25μg / (mL﹐1%). , it is necessary to eliminate the interference of co-existing components, but also enrich the gold to realize the determination of gold. The commonly used pre-separation and enrichment techniques include fire test gold method or wet separation and enrichment method. At the same time as coexisting elements, gold is also enriched. Among them, the fire assay gold method includes lead assay gold, nickel matte assay gold, tin assay gold, etc., which use metal or metal sulfide to capture precious metal elements and separate them from matrix elements. , so as to eliminate the interference of a large number of coexisting elements; wet separation and enrichment generally use aqua regia to decompose the sample, and use activated carbon, absorbent cotton, foam plastic, ion exchange resin, etc. to absorb precious metal elements such as gold, so as to separate them from the matrix elements; there are also methods of beneficiation To separate a large amount of matrix, but the effect of separating matrix elements is poor; therefore, the determination of μg / g level of gold by ordinary flame atomic absorption method can only be determined after separation and enrichment. The operation procedures are cumbersome, difficult to master, and the analysis process is long. It may also affect the recovery rate of gold, resulting in low results, or contamination during the separation process, leading to high results, using a large amount of chemical reagents, and high analysis costs

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