Sulfide mineral samples enriched in dispersed metal elements and methods of their preparation and use

Abstract

The application discloses a kind of sulfide mineral samples rich in scattered metal elements and its preparation and application method.The preparation method comprises: obtaining the salt solution of scattered metal elements with total salinity of 5-20wt%, pH is 2-3, it is hydrothermally reacted with sulfur element and calcite particles at the reaction temperature of 150-250 DEG C.The preparation method process is simple, controllability is strong, the product obtained can simulate the sulfide rich in scattered metal elements under natural mineralization conditions, and provides ideal experimental sample for studying the occurrence form and replacement mechanism of scattered elements in mineral.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mineralogy and ore deposit science, and in particular to a sulfide mineral sample rich in scattered metal elements. BACKGROUND

[0002] Scattered metal elements such as indium (In), gallium (Ga) and germanium (Ge) are widely used in the fields of electronics, optoelectronics and other high-tech fields, and are listed as key metals, but the recycling of these key metals still faces many challenges such as uneven distribution of resources, high recycling cost and technical bottlenecks.

[0003] Most of the above key metal elements are recovered as by-products in the zinc ore refining process, among which sphalerite (ZnS) is a sulfide mineral rich in various trace elements including In, Ga, Ge and other scattered metals, which has important significance in the study of geology and mineralogy and has attracted a lot of research attention. However, due to the complex interaction of elements in natural minerals and the diversity of mineral structures, the research often faces many interference factors and complex results, and it is difficult to determine the key factors controlling the super enrichment of In, Ga, Ge and other elements in the ore-forming process. Therefore, it is an urgent technical problem in the field to develop a sulfide mineral sample rich in scattered metal elements that can simulate natural conditions and has good controllability. SUMMARY

[0004] In view of the defects of the prior art, the purpose of the present application is to provide a sulfide sample rich in scattered metal elements and a preparation and application method thereof. The preparation method can successfully incorporate scattered metal elements such as In, Ga, Ge and other elements into sulfides or sulfide minerals and enrich them, forming a mineral sample that can simulate natural ore-forming conditions, providing an ideal experimental means for studying the occurrence form and replacement mechanism of scattered elements in minerals.

[0005] The technical scheme of the present application is as follows:

[0006] The preparation method of the sulfide mineral sample rich in scattered metal elements comprises:

[0007] (1) obtaining a salt solution containing scattered metal elements, the salt solution containing scattered metal elements comprising the following components: NaCl, CuCl2, CaCl2, FeCl2, ZnCl2, PbCl2 and chlorides of scattered metal elements, the pH value of the solution being 2-3, and the total salinity being 5-20wt%;

[0008] (2) hydrothermal reaction of a synthetic raw material at a reaction temperature of 150-250 DEG C and a water vapor saturation pressure to obtain the sulfide mineral sample rich in the dispersed metal elements, wherein the synthetic raw material comprises elemental sulfur, the salt solution containing the dispersed metal elements, and mineral particles;

[0009] The mineral particles comprise calcite particles.

[0010] In the above preparation method, the composition of the main metal elements in the salt solution containing the dispersed metal elements is close to the analysis result of a single fluid inclusion in a typical sedimentary rock hosting lead-zinc ore, and at a specific solution pH value and hydrothermal reaction temperature, the sulfide mineral sample rich in the dispersed metal elements and extremely similar to the mineral formed under the natural mineralization condition can be successfully obtained.

[0011] In the above preparation method, the hydrothermal reaction can be preferably carried out in a stainless steel autoclave lined with Teflon.

[0012] In the above preparation method, the hydrothermal reaction uses elemental sulfur as a sulfur source, and the elemental sulfur can rapidly react with the hydrothermal fluid in the high-temperature fluid to form hydrogen sulfide (H2S) and sulfate (SO4 2- ), i.e., the following reaction: 4S+4H2O=3H2S+2H + +SO4 2- The reaction not only provides sufficient reducing sulfur for the reaction system, but also controls the oxygen fugacity range of the reaction system near H2S-SO4 2- , which is close to the oxygen fugacity range of the actual mineralization system. The traditional sulfide preparation method such as the electrode method is difficult to accurately control the oxygen fugacity of the reaction system, especially the reaction system at a lower temperature, and the oxygen fugacity has an important influence on the enrichment mechanism of the dispersed elements in the sulfide deposit. Therefore, the traditional preparation method may not be able to reproduce the process of the sulfide enrichment of the dispersed elements in the actual mineralization process. Compared with the traditional sulfide preparation method, the present application can quickly form the sulfide mineral similar to the natural mineralization condition through the simple hydrothermal reaction, control the oxygen fugacity of the system, and successfully incorporate the dispersed metal elements into the sulfide mineral and make it rich, and the sulfide crystal shape and size are also ideal, which is convenient for a series of analysis and research in the later stage.

[0013] In the preparation method, the addition of calcite particles can form a large number of sphalerite and galena particles in the product.

[0014] In the above preparation method, the total salinity is the ratio of the mass of all chloride salts in the salt solution containing the dispersed metal elements to the total mass of the solution.

[0015] The inventors have surprisingly found that only when the elemental sulfur and the calcite particles coexist, at a specific total salinity (5-20 wt%) and hydrothermal reaction temperature, the sulfide mineral sample enriched in the dispersed metal elements can be obtained, and under other raw material selection or reaction parameters, it is often difficult to form a stable sulfide sample or the content of the dispersed metal elements in the formed sulfide sample is less to produce an enrichment effect.

[0016] According to some preferred embodiments of the present application, the particle size of the elemental sulfur is less than or equal to 0.1 mm.

[0017] The preferred embodiments can significantly improve the preparation efficiency of the above preparation method.

[0018] According to some preferred embodiments of the present application, the oxygen fugacity value of the hydrothermal reaction is controlled by an oxygen fugacity buffer pair, and the oxygen fugacity buffer pair comprises one or more of H2S-SO4 2- buffer pairs, MoO2-MoO3 buffer pairs, and Co-CoO buffer pairs.

[0019] According to some preferred embodiments of the present application, the particle size of the mineral particles is 200 μm to 1 mm.

[0020] According to some preferred embodiments of the present application, the total salinity of the salt solution containing the dispersed metal elements is 5 wt%, and the reaction temperature of the hydrothermal reaction is 250°C.

[0021] The inventors have surprisingly found that under the above reaction parameters, the efficiency of synthesizing the sulfide mineral sample is best, and the crystal form is best.

[0022] According to some preferred embodiments of the present application, in the salt solution containing the dispersed metal elements, the content of NaCl is 4-16 wt%, the content of CaCl2 is 1-4 wt%, the content of CuCl2 is 900-1100 ppm, the content of FeCl2 is 400-600 ppm, the content of ZnCl2 is 900-1100 ppm, and the content of PbCl2 is 300-500 ppm.

[0023] According to some preferred embodiments of the present application, in the salt solution containing the dispersed metal elements, the content of the chloride of the dispersed metal elements is 100-750 ppm.

[0024] According to some preferred embodiments of the present application, the dispersed metal elements include one or more of In, Ga, and Ge.

[0025] According to some preferred embodiments of the present application, the time of the hydrothermal reaction is 25-35 days.

[0026] According to some preferred embodiments of the present application, the preparation method further comprises: washing and drying the reaction product obtained by performing the hydrothermal reaction to obtain the sulfide mineral sample rich in rare and dispersed metal elements, and the drying temperature is 100-120 DEG C.

[0027] The present application further provides a sulfide mineral sample rich in rare and dispersed metal elements prepared by the above preparation method.

[0028] The sulfide mineral sample is generally about tens to hundreds of microns in size, forms a short columnar or plate-shaped chalcopyrite, and the sulfide is attached around calcite particles or is aggregated and produced alone, and the surface texture of the chalcopyrite is uniform under a microscope; in addition, a large number of sphalerite and galena particles are formed, the individual sphalerite particles are spherical, the spherical sphalerite is in a ring layer, and a large number of sphalerite are aggregated and produced in a cluster; the galena particles are cubic, and the galena particles are generally associated with the sphalerite particles. Further analysis shows that the chalcopyrite and galena contain a small amount of In, Ga and Ge elements, and the specific ring layer in the sphalerite is very rich in In, Ga and Ge elements.

[0029] The present application further provides an application method of the above sulfide mineral sample rich in rare and dispersed metal elements, which is used as a simulation sample of a mineral rich in rare and dispersed elements under natural ore-forming conditions.

[0030] According to some preferred embodiments of the present application, the application method comprises analyzing the sulfide mineral sample rich in rare and dispersed metal elements by in-situ micro-area analysis.

[0031] More preferably, the in-situ micro-area analysis method comprises one or more of EPMA, LA-ICP-MS, SIMS, EBSD and FIB-TEM.

[0032] More preferably, the analysis comprises one or more of analysis of the enrichment mechanism of rare and dispersed elements, analysis of the composition, structure and morphology of natural minerals containing rare and dispersed metal elements, and analysis of the occurrence state and content variation of rare and dispersed elements in minerals.

[0033] The present application has the following advantages:

[0034] The preparation method of the present application has strong controllability, flexible reaction conditions, simple operation steps, fast reaction rate, and is easy to repeat production, which can significantly reduce the time and economic cost of experiments;

[0035] The preparation method of the present application can obtain a sample of dispersed element-enriched minerals under simulated natural mineralization conditions, which is stable and controllable in structure, suitable for quantitative research, and provides an ideal means for studying the occurrence form and replacement mechanism of dispersed elements in minerals, which helps to deeply understand the enrichment mechanism of dispersed elements, and further provides a theoretical basis and experimental support for the genesis of ore deposits, resource potential evaluation, and environment-friendly metal extraction methods. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 SEM images of sample synthesized sphalerite and galena particles in Example 4, wherein Fig. (a) is a sphalerite cluster aggregate structure, and Fig. (b) is a sphalerite-galena particle collection in a paragenetic cluster.

[0037] Figure 2 SEM images of sample synthesized chalcopyrite and calcite particles in Example 4, wherein Fig. (a) is massive chalcopyrite attached around calcite particles, and Fig. (b) is a separate sheet chalcopyrite collection. DETAILED DESCRIPTION

[0038] The technical solutions in the present application will be further described below in combination with the embodiments of the present application. The embodiments described below are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should fall within the scope of protection of the present application.

[0039] Example 1

[0040] The sulfide mineral sample rich in dispersed metal elements is prepared by the following steps:

[0041] (1) Nitrogen is introduced into 500 ml of deionized water at room temperature for 1 hour to remove dissolved oxygen therein;

[0042] (2) Analytical grade solution components are added to the deoxygenated deionized water and mixed thoroughly to form a mixed solution with a total salinity of 5 wt.%, and in order to prevent hydrolysis reaction, a few drops of hydrochloric acid are added to the mixed solution to maintain its pH value between 2-3, to obtain a salt solution containing dispersed elements; the content of NaCl in the mixed solution is about 4 wt.%, the content of CaCl2 is about 1 wt.%, the content of CuCl2 is about 1000 ppm, the content of FeCl2 is about 500 ppm, the content of ZnCl2 is about 1000 ppm, the content of PbCl2 is about 400 ppm, and the content of InCl3, GaCl2 and GeCl2 is about 200 ppm respectively; the solution components include: NaCl, CuCl2, CaCl2, FeCl2, ZnCl2, PbCl2, InCl3, GaCl2 and GeCl2;

[0043] (3) Clean, unaltered calcite particles were selected and ground in an agate mortar to a particle size of approximately 0.5 mm. The particles were then repeatedly rinsed with deionized water and dried at 110°C to obtain mineral particles.

[0044] (4) 0.1g natural sulfur and 0.5g mineral particles were placed together with 10ml of salt solution containing scattered elements in a 20ml stainless steel autoclave lined with Teflon. The autoclave was placed in a heating furnace at 250℃ for hydrothermal reaction for 30 days. The oxygen fugacity was controlled to be close to H2S / SO4 in the hydrothermal reaction. 2- Oxygen fugacity values ​​corresponding to the buffer pairs;

[0045] (5) After the reaction is completed, the autoclave is immersed in ice water and quickly cooled to room temperature. The mineral particles are taken out and rinsed with deionized water, and then dried in an oven at 110°C for 6 hours to obtain a sulfide mineral sample rich in scattered metal elements.

[0046] Example 2

[0047] The morphology, structure, and mineral composition of the sulfide mineral sample rich in rare metal elements obtained in Example 1 were observed using a SEM electron microscope. The results showed that the size of the obtained sulfide mineral sample was generally about tens to hundreds of microns, and short columnar or plate-like crystals of chalcopyrite were formed. These sulfides were attached to the periphery of calcite particles or produced individually in aggregate. Microscopic observation showed that the surface texture of the chalcopyrite was uniform. In addition, a large number of sphalerite and galena particles were formed. The individual sphalerite particles were spherical with irregular spherical surfaces. The interior of the spherical sphalerite was ring-like, and a large number of sphalerite particles were produced in clusters. The galena particles were cubic in shape. The galena particles generally coexisted with the sphalerite particles and were embedded in the sphalerite cluster particles.

[0048] The resulting sulfide mineral samples, rich in rare metal elements, were fixed on conductive adhesive and carbon- or gold-plated before EDS microanalysis. The results showed relatively weak signals for In, Ga, and Ge in chalcopyrite and galena, while strong signals for these elements were observed in specific layers within sphalerite, indicating that sphalerite has the potential for exceptional enrichment of these elements.

[0049] Example 3

[0050] The sulfide mineral sample rich in rare metal elements obtained in Example 1 was subjected to microanalysis, and the analysis process was as follows:

[0051] The obtained sulfide mineral sample rich in scattered metal elements was fixed in a resin target with a diameter of 2.5 cm, and was mechanically polished using silicon-carbon paper with mesh numbers of 320, 600 and 1200 in sequence, and a water-free lubricant was used for polishing, and then the sample was ground using diamond sandpaper with mesh numbers of 15 μm, 5 μm, 1 μm, 0.5 μm and 0.25 μm in sequence, and a water-free lubricant was also used for grinding, and then the sample was carbon-coated or gold-coated, and then EPMA and LA-ICP-MS micro-area analysis of major and trace elements were performed.

[0052] The analysis results show that the contents of In, Ga and Ge elements in the specific ring layer of the sphalerite can reach hundreds to thousands of ppm, which indicates that the specific structure of the sphalerite can be beneficial to the super-enrichment of In, Ga and Ge elements, and the contents of In, Ga and Ge elements in the galena and chalcopyrite are only a few to tens of ppm.

[0053] Example 4

[0054] The sulfide mineral samples numbered 1-16 were prepared by the same steps as in Example 1, and the only difference is that the total salinity of the salt solution containing scattered elements, the temperature of the hydrothermal reaction, the mineral composition and the sulfur source were adjusted, as shown in Table 1 below:

[0055] Table 1 Synthesis conditions of the sulfide mineral samples numbered 1-16

[0056]

[0057]

[0058] The analysis of the sulfide mineral samples numbered 1-16 found that only the sulfide mineral samples numbered 5-8 formed minerals rich in scattered elements such as In, Ga and Ge, such as chalcopyrite, bornite, sphalerite and galena, among which the sphalerite was in the form of spherical clusters, the galena was in the form of a cube, the chalcopyrite and bornite were in the form of irregular clusters, and the sphalerite contained trace amounts of elements such as Cu, Fe, In, Ga and Ge. The micro-morphology of sample 6 is shown in FIG. 1, and the micro-morphology of sample 8 is shown in FIG. 2. Figure 1 Figure 2

[0059] The analysis also found that the higher the hydrothermal reaction temperature, the lower the salinity of the salt solution, and the better the crystal form of the sphalerite in the sample added with calcite, i.e. the sulfide mineral synthesized in a 5% salinity salt solution and at a hydrothermal reaction temperature of 250°C has the best efficiency and crystal form.

[0060] ​​In the 9-16 sulfide mineral samples, although the mineral form of sulfur source, i.e. pyrite, is used as the sulfur source, only a small amount of sulfide mineral is generated in the obtained product, chalcopyrite and bornite containing trace amounts of Zn, Pb, In, Ga and Ge and other elements are formed, sphalerite and galena are not formed, and the sulfide mineral sample rich in rare and dispersed metal elements cannot be obtained.

[0061] It should be noted that the above only describes the preferred embodiments of the present application, which should not limit the protection scope of the technical solutions of the present application. Any modification made by those skilled in the art to the technical solutions described in the foregoing embodiments, equivalent replacement of technical features, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method for preparing a sulfide mineral sample rich in rare metal elements, characterized in that: It includes: (1) obtaining a salt solution containing rare metal elements, wherein the salt solution containing rare metal elements comprises the following components: NaCl, CuCl2, CaCl2, FeCl2, ZnCl2, PbCl2, and chlorides of the rare metal elements, wherein the pH value of the solution is 2-3 and the total salinity is 5-20 wt%; (2) subjecting the synthetic raw materials to a hydrothermal reaction at a reaction temperature of 150-250° C. and a saturated water vapor pressure to obtain the sulfide mineral sample rich in rare metal elements, wherein the synthetic raw materials include elemental sulfur, the salt solution containing the rare metal elements, and mineral particles; The mineral particles include calcite particles.

2. The preparation method according to claim 1, characterized in that in, The particle size of the sulfur element is less than 0.1 mm; and / or the particle size of the mineral particles is 200 μm to 1 mm.

3. The preparation method according to claim 1, characterized in that The total salinity of the salt solution containing scattered metal elements is 5 wt %, and the reaction temperature of the hydrothermal reaction is 250° C.

4. The preparation method according to claim 1, characterized in that In the salt solution containing rare metal elements, the content of NaCl is 4-16wt%, the content of CaCl2 is 1-4wt%, the content of CuCl2 is 900-1100ppm, the content of FeCl2 is 400-600ppm, the content of ZnCl2 is 900-1100ppm, and the content of PbCl2 is 300-500ppm.

5. The preparation method according to claim 1, characterized in that In the salt solution containing the rare metal elements, the content of chloride of the rare metal elements is 100-750 ppm.

6. The preparation method according to claim 1, characterized in that The rare metal elements include one or more of In, Ga, and Ge.

7. The preparation method according to claim 1, characterized in that The hydrothermal reaction time is 25-35 days.

8. The preparation method according to claim 1, characterized in that The method further comprises: washing and drying the reaction product obtained by the hydrothermal reaction to obtain the sulfide mineral sample rich in rare metal elements, wherein the drying temperature is 100-120°C.

9. A sulfide mineral sample rich in rare metal elements prepared by the preparation method according to any one of claims 1 to 8.

10. The method for using the sulfide mineral sample rich in rare metal elements according to claim 9, comprising: It is used as a simulated sample of minerals enriched with rare elements under natural mineralization conditions.

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