Method for extracting germanium from high-silicon high-iron low-grade germanium-containing material

Abstract

The invention belongs to the technical field of wet metallurgy, and in particular, relates to a method for extracting germanium from a high-silicon high-iron low-grade germanium-containing material. The method comprises the steps: mixing the high-silicon high-iron low-grade germanium-containing material with sulfuric acid and a leaching aid agent, adding the mixture into a high pressure reaction kettle, introducing oxygen-containing gas, adjusting the oxygen partial pressure, carrying out oxygen pressure acid leaching, and carrying out solid-liquid separation of the obtained material, to obtain a germanium-containing acid leaching solution; adding an iron powder and gelatin, to obtain a purified solution; and extracting and carrying out back extraction, and finally, calcining to obtain a refined germanium ore with the germanium content of more than 30%. The method has the advantages of short flow, low energy consumption, high metal germanium leaching rate and recovery rate, low production cost, easy operation, and convenience in industrialized production.

Description

technical field [0001] The invention belongs to the technical field of hydrometallurgy, in particular to a method for extracting germanium from high-silicon, high-iron and low-grade germanium-containing materials. Background technique [0002] Germanium is a rare metal element, and it is difficult to form independent deposits in nature. It is mainly distributed in polymetallic or non-metallic ores and waste residues generated during the smelting process. These germanium-containing materials, whether they are germanium-containing polymetallic ores or The grades of germanium-containing non-metallic ores and germanium-containing smelting residues are relatively low (<0.5%), which are far below the index of germanium concentrates (>10%). More importantly, these germanium-containing Germanium materials usually contain a large amount of base metals and impurity elements, such as Zn, Pb, Fe, Si, etc., and the content of impurities Fe and Si is relatively high. In addition, ge...

AI Technical Summary

Problems solved by technology

[0002] Germanium is a rare metal element, and it is difficult to form independent deposits in nature. It is mainly distributed in polymetallic or non-metallic ores and waste residues generated during the smelting process. These germanium-containing materials, whether they are germanium-containing polymetallic ores or The grades of germanium-containing non-metallic ores and germanium-containing smelting residues are relatively low (10%). More importantly, these germanium-containing Germanium materials usually contain a large amount of base metals and impurity elements, such as Zn, Pb, Fe, Si, etc., and the content of impurities Fe and Si is relatively high. In addition, germanium has the properties of iron and silicon, so it is usually mixed with The occurrence state of the package exists in the material, which belongs to a complex germanium-containing material. This feature makes the leaching of germanium difficult, the leaching rate is low, the separation and enrichment is difficult, and the recovery rate is low.

[0003] The key to extracting germanium from high-silicon, high-iron and low-grade germanium-containing materials lies in the efficient leaching, separation and enrichment of germanium; at present, the recovery methods for germanium in germanium-containing materials include fire method and wet process, and the recovery of germanium by using the rotary kiln volatilization process, Only about 85% of germanium is enriched in the dust, and some germanium will enter the kiln slag and cannot be fully recovered. At the same time, the rotary kiln volatilization process still has disadvantages such as high energy consumption and serious pollution; due to the high silicon and high iron slag The phase of germanium is complex, in addition to oxides, there are elemental metals and sulfides, etc., and it is wrapped by silicon; the leaching effect is poor when using conventional acid leaching technology, and the leaching rate of germanium is usually only about 60%; The leaching rate of germanium can reach about 80% in stage acid leaching treatment of germanium-containing materials, but the process is long and requires strict acidity control; the process of atmospheric pressure acid leaching and adding leaching aids can increase the leaching rate of germanium, It can reach more than 90%, but the filtration performance of the leaching slurry is poor; the leaching rate of germanium can reach about 90% by adding a strong oxidant or introducing oxygen-containing gas in the oxidative acid leaching process, but the filtration performance of the leaching slurry is poor; In order to eliminate the influence of silicon in the raw material on the leaching of germanium, the mixed acid leaching process of sulfuric acid and hydrofluoric acid can significantly increase the leaching rate of germanium and improve the filtration performance of the leaching slurry, and the leaching rate of germanium can reach more than 90%. However, fluoride ions seriously corrode the equipment, and the fluorine-containing waste liquid is difficult to deal with, causing environmental pollution; the process of oxygen pressure acid leaching and adding leaching aids can significantly improve the leaching effect of germanium and the filtration performance of the leaching slurry, and the leaching of germanium The rate can reach more than 98%, but because the leaching rate of germanium is increased, silicon and iron are almost completely leached, and the content of silicon and iron in the leaching solution is relatively high, which is very unfavorable for the subsequent extraction of germanium

[0004] Based on the characteristics of high-silicon, high-iron and low-grade germanium-containing materials, the content of impurity silicon and iron is high, the content of valuable metal germanium is low, and the occurrence state of germanium is complicated. The existing wet extraction technology for germanium is used to improve the leaching of germanium. At the same time, silicon and iron are almost completely leached; when the content of silicon dioxide in the leaching solution is greater than 100mg / L, the extraction will emulsify, and in severe cases, the extraction cannot be carried out, which seriously affects the extraction effect of germanium; when the leaching solution When the content of iron ions in the medium is too high, no matter whether tannin precipitation or organic solvent is used to extract germanium, the separation effect is not ideal. Not only the extraction or tannin precipitation rate is low, but also the obtained germanium concentrate has high iron content and low germanium grade. , indicating that the impurity elements iron and silicon are one of the main reasons why it is difficult to efficiently leach, separate and recover germanium in the existing technology

Images