Preparation and application method of copper-sulfur separation inhibitor for flotation copper removal of copper-containing gold concentrate

Abstract

The invention provides a preparation and application method of a copper-sulfur separation inhibitor for flotation copper removal of copper-containing gold concentrate, and belongs to the technical field of beneficiation reagents. The preparation method comprises the following steps: adding a mercaptosilane solution into an acidic glycan low-molecular biomass compound suspension, carrying out primary modification in a stirring state, and carrying out heating treatment to further react until the reaction is complete, so that functional groups on the surface of the glycan low-molecular biomass compound are changed by silanization treatment to obtain the modified glycan low-molecular biomass compound. The prepared copper-sulfur separation inhibitor has a relatively strong selective inhibition effect on copper minerals. When the prepared copper-sulfur separation inhibitor is applied to the flotation copper removal process of the copper-containing gold concentrate, flotation can be conducted in the neutral or weak acid environment, copper minerals in the copper-containing gold concentrate can be effectively removed with a small amount of the copper-sulfur separation inhibitor, copper removal of the copper-containing gold concentrate is simply, conveniently and efficiently achieved, and the copper removal rate of the copper-containing gold concentrate is increased. And the low-copper gold concentrate with the higher gold grade is obtained with the higher gold recovery rate, and the high practical application value is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of ore dressing agents, and in particular to a preparation and application method of a copper-sulfur separation inhibitor for flotation removal of copper from copper-gold concentrate. Background Art

[0002] In the leaching process of copper-containing gold concentrate, the presence of copper minerals will increase the consumption of cyanide, reduce the concentration of free cyanide in the pulp, and slow down the leaching rate of gold; on the other hand, it will form a film on the gold surface, hindering the leaching of gold. Therefore, in order to efficiently leach gold from copper-containing gold concentrate, it is necessary to first remove the copper minerals in the copper-containing gold concentrate.

[0003] The gold in the copper-gold concentrate mainly exists in pyrite, while copper minerals such as chalcopyrite and pyrite are closely coexisting. The operation of separating the two is called copper-sulfur separation. Copper-sulfur separation has always been an important issue in mineral processing. Since chalcopyrite and pyrite have similar floatability under low-alkali conditions, the conventional copper-sulfur separation method is to use lime as a copper-sulfur separation inhibitor during flotation to inhibit pyrite, thereby achieving copper-sulfur separation by suppressing sulfur and floating copper. However, due to the high content of pyrite in gold concentrate, a large amount of lime is needed when using lime to inhibit pyrite, which not only poses a safety hazard, but also leads to problems such as excessive cost, corrosion of equipment, and environmental pollution.

[0004] In the prior art, the patent with publication number CN112604816A provides a copper-sulfur separation inhibitor, a copper-sulfur flotation separation method and application without lime conditions. The patent prepares the copper-sulfur separation inhibitor by mixing raw materials such as sodium carbonate, ammonium sulfate, calcium chloride and sodium hydroxide in specific dosage ratios, so that it can replace the traditional lime inhibitor. However, the copper-sulfur separation inhibitor used in the patent still needs to use alkaline raw materials such as sodium carbonate and sodium hydroxide, and this copper-sulfur separation inhibitor is more suitable for the flotation of copper minerals, and is not suitable for flotation removal of copper from copper-gold concentrates.

[0005] In view of this, it is still necessary to provide an improved method for preparing and applying a copper-sulfur separation inhibitor for flotation removal of copper from copper-containing gold concentrate to solve the above problems. Summary of the invention

[0006] In view of the technical problems existing in the background technology, the present application provides a method for preparing and applying a copper-sulfur separation inhibitor for flotation removal of copper from copper-containing gold concentrate, aiming to develop a copper-sulfur separation inhibitor with low toxicity, high efficiency, good biodegradability, strong inhibition and good selectivity, which is used to effectively and selectively inhibit copper minerals such as chalcopyrite, thereby achieving efficient flotation removal of copper from copper-containing gold concentrate.

[0007] In a first aspect, the present application provides a method for preparing a copper-sulfur separation inhibitor for flotation removal of copper from copper-containing gold concentrate, comprising the following steps:

[0008] S1. preparing a polysaccharide low molecular weight biomass compound suspension and a mercaptosilane solution respectively;

[0009] S2. adding a pH regulator to the polysaccharide low molecular weight biomass compound suspension to prepare an acidic polysaccharide low molecular weight biomass compound suspension;

[0010] S3. adding the mercaptosilane solution to the acidic polysaccharide low molecular weight biomass compound suspension, stirring thoroughly, to obtain a preliminary modified polysaccharide low molecular weight biomass compound suspension;

[0011] S4. The preliminarily modified polysaccharide low molecular weight biomass compound suspension is subjected to a heating treatment, and after the reaction is complete, the product is washed and dried to obtain a copper-sulfur separation inhibitor.

[0012] In the technical solution of the embodiment of the present application, the polysaccharide low molecular biomass compound is modified by using a mercaptosilane solution, and a new functional group is introduced on the basis of maintaining the polymer molecular skeleton, so that the prepared inhibitor can have a strong selective inhibitory effect on copper minerals such as chalcopyrite, and only a small amount is needed to effectively selectively inhibit copper minerals, thereby achieving efficient flotation and copper removal of copper-containing gold concentrates. In addition, the polysaccharide low molecular biomass compound used in the present application is a bio-based raw material with good biodegradability. Compared with conventional inhibitors, it is more environmentally friendly and conforms to the development concept of green mines, while expanding the types of copper-sulfur separation inhibitors in the mineral resources industry.

[0013] In some embodiments, in step S1, the polysaccharide low molecular weight biomass compound includes one or more of nanocellulose, hemicellulose, and hemicellulose-polylactic acid complex polysaccharide; the mercaptosilane includes one or more of 3-mercaptopropyltrimethoxysilane and γ-mercaptopropyltriethoxysilane.

[0014] In this embodiment, by using specific types of polysaccharide low molecular weight biomass compounds and mercaptosilane, the selectivity of the prepared copper-sulfur separation inhibitor can be more effectively improved.

[0015] In some embodiments, in step S1, the mass concentration of the polysaccharide low molecular weight biomass compound suspension is 0.1% to 5%, and the mass concentration of the mercaptosilane solution is 10% to 20%.

[0016] In this embodiment, the polysaccharide low molecular weight biomass compound in the polysaccharide low molecular weight biomass compound suspension can be fully dispersed, and the mercaptosilane in the mercaptosilane solution can be fully dissolved, so that the subsequent reaction can proceed.

[0017] In some embodiments, in step S2, the pH value of the acidic polysaccharide low molecular weight biomass compound suspension is 3-5.

[0018] In this embodiment, the pH value of the polysaccharide low-molecular biomass compound suspension is adjusted to a specific range, which is beneficial to promote the reaction between mercaptosilane and the polysaccharide low-molecular biomass compound.

[0019] In some embodiments, in step S3, the mass of the mercaptosilane added to the mercaptosilane solution is 0.5 to 1.5 times the solid mass of the polysaccharide low molecular weight biomass compound in the acidic polysaccharide low molecular weight biomass compound suspension.

[0020] In this embodiment, a better modification effect can be obtained by adjusting the ratio between mercaptosilane and polysaccharide low molecular weight biomass compounds.

[0021] In some embodiments, in step S4, during the heating treatment, the heating temperature is 60-100° C. and the heating time is 3-5 hours.

[0022] In this embodiment, by heating the initially modified polysaccharide low molecular weight biomass compound at a specific temperature for a certain period of time, the initially modified polysaccharide low molecular weight biomass compound can be further reacted to completion, thereby improving the modification effect and further improving the selective inhibition of copper minerals by the prepared copper-sulfur separation inhibitor.

[0023] In a second aspect, an embodiment of the present application provides an application method of a copper-sulfur separation inhibitor for flotation removal of copper from a copper-containing gold concentrate, wherein the copper-sulfur separation inhibitor prepared in the above scheme is applied to the flotation removal of copper from a copper-containing gold concentrate, comprising the following steps:

[0024] After grinding the copper-gold concentrate, it is prepared into slurry;

[0025] dissolving the copper-sulfur separation inhibitor in water to prepare an inhibitor suspension;

[0026] The pH value of the slurry is adjusted to 6-7, and then the inhibitor suspension is added. After sufficient stirring, a collector and a frother are added to perform flotation operations to obtain high-copper-gold concentrate and low-copper-gold concentrate.

[0027] In the technical solution of the embodiment of the present application, by applying the copper-sulfur separation inhibitor prepared in the above solution to the flotation copper removal process of the copper-containing gold concentrate, flotation can be carried out in a neutral or weakly acidic environment, and the copper minerals in the copper-containing gold concentrate can be effectively removed with a small amount of copper-sulfur separation inhibitor, thereby achieving copper removal from the copper-containing gold concentrate in a simple and efficient manner, and obtaining a low-copper gold concentrate with a higher gold grade with a higher gold recovery rate.

[0028] In some embodiments, the grinding fineness of the grinding treatment is that particles with a size less than 400 mesh account for 60% to 90%; and the mass concentration of the slurry is 25% to 35%.

[0029] In some embodiments, the mass concentration of the copper-sulfur separation inhibitor in the inhibitor suspension is 1% to 10%.

[0030] In some embodiments, the flotation operation includes one roughing operation and 1 to 4 scavenging operations; during the roughing operation, the amount of the copper-sulfur separation inhibitor used is 10 to 1000 g / t, and during each level of scavenging operation, the amount of the copper-sulfur separation inhibitor used is halved successively.

[0031] In this embodiment, since the copper-sulfur separation inhibitor used has a good selective inhibitory effect on copper minerals, a good inhibitory effect can be achieved with a smaller dosage, which effectively reduces the dosage of the agent and reduces the cost of the agent.

[0032] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings used in the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0034] Figure 1 This is a schematic diagram of the flotation process when the copper-sulfur separation inhibitor is applied to the flotation removal of copper from copper-containing gold concentrate in the embodiments of the present application. DETAILED DESCRIPTION

[0035] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0037] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0038] The traditional copper-sulfur separation method mainly uses alkaline raw materials such as lime as copper-sulfur separation inhibitors to inhibit pyrite, thereby achieving copper-sulfur separation by inhibiting sulfur and flotation of copper. However, this method is not suitable for gold concentrates with high pyrite content, which will lead to problems such as excessive use of inhibitors, corrosion of equipment, and environmental pollution.

[0039] In order to solve the above problems, the present application provides a method for preparing and applying a copper-sulfur separation inhibitor for flotation removal of copper from copper-containing gold concentrate, by subjecting polysaccharide low-molecular biomass compounds to silanization treatment to change the functional groups on their surface so that they can selectively inhibit copper minerals such as chalcopyrite, thereby achieving efficient flotation removal of copper from copper-containing gold concentrate by inhibiting copper flotation sulfur.

[0040] In a first aspect, the present application provides a method for preparing a copper-sulfur separation inhibitor for flotation removal of copper from copper-containing gold concentrate, comprising the following steps:

[0041] S1. preparing a polysaccharide low molecular weight biomass compound suspension and a mercaptosilane solution respectively;

[0042] S2. adding a pH regulator to the polysaccharide low molecular weight biomass compound suspension to prepare an acidic polysaccharide low molecular weight biomass compound suspension;

[0043] S3. adding the mercaptosilane solution to the acidic polysaccharide low molecular weight biomass compound suspension, stirring thoroughly, to obtain a preliminary modified polysaccharide low molecular weight biomass compound suspension;

[0044] S4. The preliminarily modified polysaccharide low molecular weight biomass compound suspension is subjected to a heating treatment, and after the reaction is complete, the product is washed and dried to obtain a copper-sulfur separation inhibitor.

[0045] In the technical scheme of the embodiment of the present application, the polysaccharide low molecular biomass compound is modified by using a mercaptosilane solution, and a new functional group is introduced on the basis of maintaining the polymer molecular skeleton, so that the obtained inhibitor can have a strong selective inhibition effect on copper minerals such as chalcopyrite, and the targeted capture ability of the target element can be achieved. At the same time, the rich derivatization sites in the molecular skeleton of the polysaccharide low molecular biomass compound ensure the high-density chemical bonding of the functional functional groups, so that the density of the functional functional groups in the unit segment is higher, and compared with the traditional dosage of the agent, only a small amount is needed to effectively selectively inhibit the copper minerals, and the efficient flotation removal of copper-containing gold concentrate is achieved, and the expected goal of low cost is achieved at the same time. In addition, the polysaccharide low molecular biomass compound used in this application is a bio-based raw material with good biodegradability. Compared with conventional inhibitors, it is more green and environmentally friendly, in line with the development concept of green mines, and at the same time expands the types of copper-sulfur separation inhibitors that are easy to use in the mineral resources industry.

[0046] Furthermore, in some embodiments, in step S1, the mass concentration of the polysaccharide low molecular weight biomass compound suspension is 0.1% to 5%, and the mass concentration of the mercaptosilane solution is 10% to 20%.

[0047] In the technical scheme of the embodiment of the present application, the preparation method of the polysaccharide low molecular biomass compound suspension can be: adding the polysaccharide low molecular biomass compound to water, stirring for 10 minutes by a magnetic stirrer, so that the polysaccharide low molecular biomass compound is fully dispersed, that is, a polysaccharide low molecular biomass compound suspension is obtained. The preparation method of the mercaptosilane solution can be: adding mercaptosilane to a solvent, stirring for 10 minutes by a magnetic stirrer, so that the mercaptosilane is fully dissolved, that is, a mercaptosilane solution is obtained, wherein the solvent is preferably ethanol. On this basis, by controlling the mass concentration of the polysaccharide low molecular biomass compound suspension to 0.1% to 5%, and controlling the mass concentration of the mercaptosilane solution to 10% to 20%, it is beneficial to fully disperse the polysaccharide low molecular biomass compound and fully dissolve the mercaptosilane, which is convenient for subsequent reactions.

[0048] Furthermore, in some embodiments, in step S1, the polysaccharide low molecular weight biomass compound includes one or more of nanocellulose, hemicellulose, and hemicellulose-polylactic acid complex polysaccharide; the mercaptosilane includes one or more of 3-mercaptopropyltrimethoxysilane and γ-mercaptopropyltriethoxysilane.

[0049] In the technical solution of the embodiment of the present application, by adopting specific types of polysaccharide low molecular weight biomass compounds and mercaptosilanes, mercaptosilane groups or functional groups of mercaptosilane chains can be introduced on the surface of the polysaccharide low molecular weight biomass compounds, thereby more effectively improving the selectivity of the prepared copper-sulfur separation inhibitor.

[0050] Furthermore, in some embodiments, in step S2, the pH value of the acidic polysaccharide low molecular weight biomass compound suspension is preferably 3-5, more preferably 4; and the pH adjuster is preferably hydrochloric acid.

[0051] In the technical solution of the embodiment of the present application, by adjusting the pH value of the polysaccharide low-molecular biomass compound suspension to a specific range, it is beneficial to promote the reaction of mercaptosilane and the polysaccharide low-molecular biomass compound.

[0052] Furthermore, in some embodiments, in step S3, the mass of the mercaptosilane added to the mercaptosilane solution is 0.5 to 1.5 times the solid mass of the polysaccharide low molecular weight biomass compound in the acidic polysaccharide low molecular weight biomass compound suspension.

[0053] In the technical solution of the embodiment of the present application, a better modification effect can be obtained by adjusting the ratio between mercaptosilane and polysaccharide low molecular weight biomass compound. Furthermore, after adding the mercaptosilane solution, it is preferably stirred with a magnetic stirrer at room temperature for 2.5 to 3.5 hours to allow the mercaptosilane and polysaccharide low molecular weight biomass compound to fully react.

[0054] Furthermore, in some embodiments, in step S4, during the heating treatment, the heating temperature is 60-100° C., and the heating time is 3-5 hours.

[0055] In the technical solution of the embodiment of the present application, by heating the preliminarily modified polysaccharide low molecular biomass compound at a specific temperature for a certain period of time, the preliminarily modified polysaccharide low molecular biomass compound can be further reacted to completion, thereby improving the modification effect, and further improving the selective inhibition effect of the obtained copper-sulfur separation inhibitor on copper minerals. Furthermore, the heating treatment method is preferably water bath heating to ensure uniform heating.

[0056] Furthermore, in some embodiments, the washing liquid used in the washing in step S4 is preferably deionized water or an ethanol solution, and the washing may be repeated multiple times, preferably 3 to 5 times.

[0057] In a second aspect, an embodiment of the present application provides an application method of a copper-sulfur separation inhibitor for flotation removal of copper from a copper-containing gold concentrate, wherein the copper-sulfur separation inhibitor prepared in the above scheme is applied to the flotation removal of copper from a copper-containing gold concentrate, comprising the following steps:

[0058] After grinding the copper-gold concentrate, it is prepared into slurry;

[0059] dissolving the copper-sulfur separation inhibitor in water to prepare an inhibitor suspension;

[0060] The pH value of the slurry is adjusted to 6-7, and then the inhibitor suspension is added. After sufficient stirring, a collector and a frother are added to perform flotation operations to obtain high-copper-gold concentrate and low-copper-gold concentrate.

[0061] In the technical solution of the embodiment of the present application, by applying the copper-sulfur separation inhibitor prepared in the above solution to the flotation copper removal process of the copper-containing gold concentrate, flotation can be carried out in a neutral or weakly acidic environment, and the copper minerals in the copper-containing gold concentrate can be effectively removed with a small amount of copper-sulfur separation inhibitor, thereby achieving copper removal from the copper-containing gold concentrate in a simple and efficient manner, and obtaining a low-copper gold concentrate with a higher gold grade with a higher gold recovery rate.

[0062] Furthermore, in some embodiments, the grinding fineness of the grinding treatment is that particles with a particle size less than 400 mesh account for 60% to 90%; and the mass concentration of the slurry is 25% to 35%.

[0063] Furthermore, in some embodiments, the mass concentration of the copper-sulfur separation inhibitor in the inhibitor suspension is 1% to 10% to facilitate better dispersion of the inhibitor; meanwhile, the collector is preferably prepared into a collector solution before use, and the mass concentration of the collector in the collector solution is preferably 1% to 5%.

[0064] Furthermore, in some embodiments, the flotation operation includes one roughing and 1 to 4 scavenging; during the roughing, the amount of the copper-sulfur separation inhibitor is 10 to 1000 g / t, the amount of the collector is 0 to 100 g / t, and the amount of the frother is 10 to 50 g / t; during each level of scavenging, the amount of the copper-sulfur separation inhibitor, collector, and frother is halved. It should be noted that in this application, the amount of each reagent is determined based on the mass of the original ore, that is, the amount of reagent corresponding to each ton of copper-gold concentrate.

[0065] Furthermore, in some embodiments, after adding the inhibitor suspension, stirring is performed for 5 to 10 minutes; then the collector is added and stirred for 2 to 5 minutes; then the frother is added and stirred for 2 to 3 minutes, and then aeration roughing is performed, and the roughing time is 4 to 6 minutes. Based on this, it is convenient for each reagent to fully contact and react with the mineral particles, thereby improving the flotation effect.

[0066] In the application method of the copper-sulfur separation inhibitor, since the copper-sulfur separation inhibitor used has a good selective inhibitory effect on copper minerals, a better inhibitory effect can be achieved with a smaller dosage, which effectively reduces the dosage of the agent and reduces the cost of the agent.

[0067] Some specific embodiments are listed below. It should be noted that the embodiments described below are exemplary and are only used to explain the present application, and should not be construed as limiting the present application. If specific techniques or conditions are not specified in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. The reagents or instruments used without specifying the manufacturer are all conventional products that can be obtained commercially.

[0068] Example 1

[0069] This embodiment provides a method for preparing and applying a copper-sulfur separation inhibitor for flotation removal of copper from copper-containing gold concentrate. The method for preparing the copper-sulfur separation inhibitor specifically comprises the following steps:

[0070] S1. Add 50 g of nanocellulose to 950 mL of water, stir for 10 min using a magnetic stirrer to prepare a nanocellulose suspension with a mass concentration of 5%; add 50 g of 3-mercaptopropyltrimethoxysilane to 200 g of ethanol, stir for 10 min using a magnetic stirrer to prepare a mercaptosilane solution with a mass concentration of 20%.

[0071] S2. Add hydrochloric acid to the nanocellulose suspension to adjust the pH value of the nanocellulose suspension to 4.

[0072] S3. Add the freshly prepared mercaptosilane solution dropwise to the nanocellulose suspension at pH 4 using a pipette, and stir with a magnetic stirrer at room temperature for 3 h to allow 3-mercaptopropyltrimethoxysilane to fully react with the polysaccharide low molecular weight biomass compound to obtain a preliminarily modified nanocellulose suspension;

[0073] S4. The preliminarily modified nanocellulose suspension is placed in a beaker, heated to 85° C. in a water bath, and further reacted to completion for 4 hours. Thereafter, the product is washed with distilled water and dried to obtain a copper-sulfur separation inhibitor.

[0074] The copper-sulfur separation inhibitor prepared in this embodiment can be applied to the flotation of copper-containing gold concentrate. In this embodiment, the gold grade of the copper-containing gold concentrate is 18.70 g / t, the copper grade is 1.48%, and the sulfur grade is 33.97%. The gold-containing minerals in the ore are mainly pyrite, and the copper-containing minerals are mainly chalcopyrite and bornite. When the copper-sulfur separation inhibitor is applied to the flotation removal of copper from the copper-containing gold concentrate, the flow diagram is as follows: Figure 1 As shown, the specific steps include:

[0075] The copper-gold concentrate is ground with a ball mill until the particles with a particle size less than 400 mesh account for 90%, and the concentrate is prepared into a slurry with a concentration of 28%. Then the pH value of the slurry is adjusted to 6, and the prepared copper-sulfur separation inhibitor is added with water to prepare an inhibitor suspension with a mass concentration of 10%. According to the addition of 500g of copper-sulfur separation inhibitor per ton of ore, the inhibitor suspension is added to the slurry with a pH value of 6 and stirred for 10 minutes; then 10g / t of isopentyl xanthate and 5g / t of butyl ammonium black medicine are added as collectors and stirred for 5 minutes; then 10g / t of 2# oil is added as a foaming agent, stirred for 2 minutes, and roughing is carried out to obtain roughing concentrate and roughing tailings. Then the rougher tailings are scavenged three times, and the dosage of reagents is halved successively (i.e., the amount of inhibitor added in the first scavenging is 400g / t, the second scavenging is 200g / t, the third scavenging is 100g / t, and the dosage of other reagents is determined in the same way). The concentrate obtained from each scavenging is combined with the rougher concentrate as the concentrate, i.e., low-copper-gold concentrate, which can be used for gold smelting. The tailings finally obtained from the scavenging are high-copper-gold concentrate, which can be used for copper smelting.

[0076] Comparative Examples 1 to 3

[0077] Compared with Example 1, the difference of Comparative Example 1 is that no copper-sulfur separation inhibitor is added during the flotation of copper-containing gold concentrate to remove copper; the difference of Comparative Example 2 is that the copper-sulfur separation inhibitor prepared in Example 1 is replaced by an equal amount of nanocellulose; the difference of Comparative Example 3 is that the mercaptosilane solution used in Example 1 is replaced by an equal amount of N-propyltriethoxysilane. The remaining steps in each comparative example are consistent with Example 1 and are not repeated here.

[0078] After flotation and copper removal from the same copper-containing gold concentrate according to the methods provided in Example 1 and Comparative Examples 1 to 3, the results are shown in Table 1.

[0079] Table 1 Flotation results of Example 1 and Comparative Examples 1 to 3

[0080]

[0081] It can be seen from Table 1 that when the copper inhibitor is not used, the difference between the gold and copper recovery rates is small, and both gold and copper minerals show good floatability; when the unmodified nanocellulose is used, while the copper minerals are inhibited, the floating of gold-containing minerals is also inhibited to a certain extent; when the nanocellulose is silanized and modified with N-propyltriethoxysilane, the floating of gold and copper minerals in flotation is greatly inhibited; when the copper inhibitor in Example 1 is used, the introduction of the thiol group enhances the selectivity of the inhibitor, and the recovery rate of gold and copper minerals is quite different, showing obvious targeted inhibition ability.

[0082] Example 2

[0083] This embodiment provides a preparation and application method of a copper-sulfur separation inhibitor for flotation removal of copper from copper-gold concentrate. Compared with Example 1, the difference lies in that the nanocellulose suspension and mercaptosilane solution prepared in step S1 are changed, and the pH value of the slurry is adjusted to 7 during the application process. The remaining steps are consistent with Example 1 and are not repeated here.

[0084] In this embodiment, 10 g of nanocellulose was added to 990 mL of water and stirred for 10 min by a magnetic stirrer to prepare a nanocellulose suspension with a mass concentration of 1%; 50 g of γ-mercaptopropyltriethoxysilane was added to 450 g of ethanol and stirred for 10 min by a magnetic stirrer to prepare a mercaptosilane solution with a mass concentration of 10%.

[0085] Comparative Examples 4 to 6

[0086] Compared with Example 2, the difference of Comparative Example 4 is that no copper-sulfur separation inhibitor is added when copper-containing gold concentrate is flotated to remove copper; the difference of Comparative Example 5 is that step S2 of Example 2 is omitted, the pH value of the nanofiber suspension is not adjusted, and the mercaptosilane solution is directly added to the prepared nanofiber suspension; the difference of Comparative Example 6 is that the water bath heating step in step S4 of Example 2 is omitted, and the preliminarily modified nanocellulose is directly used as a copper-sulfur separation inhibitor. The remaining steps in each comparative example are consistent with Example 1 and are not repeated here.

[0087] After flotation and copper removal from the same copper-containing gold concentrate according to the methods provided in Example 2 and Comparative Examples 4 to 6, the results are shown in Table 2.

[0088] Table 2 Flotation results of Example 2 and Comparative Examples 4 to 6

[0089]

[0090]

[0091] It can be seen from Table 2 that the copper inhibitor in Example 2 has better selectivity, and significantly expands the difference in flotation gold and copper recovery rates compared to Comparative Example 4; it can also be seen from Comparative Examples 5 and 6 that the selectivity of the copper inhibitor obtained is affected to a certain extent if the pH of the nanosuspension is not adjusted or the water bath heating process is omitted.

[0092] Embodiments 3 to 5

[0093] Examples 3 to 5 respectively provide a preparation and application method of a copper-sulfur separation inhibitor for flotation removal of copper from copper-containing gold concentrate. Compared with Example 1, the only difference is that the types of polysaccharide low molecular weight biomass compound and mercaptosilane are changed, and the remaining steps are consistent with Example 1, which will not be repeated here. The types of polysaccharide low molecular weight biomass compound and mercaptosilane used in each example are shown in Table 3.

[0094] Table 3 Types of polysaccharide low molecular weight biomass compounds and mercaptosilanes in Examples 3 to 5

[0095]

[0096]

[0097] After flotation and copper removal from the same copper-containing gold concentrate according to the methods provided in Examples 3 to 5, the results are shown in Table 4.

[0098] Table 4 Flotation results of Examples 3 to 5

[0099]

[0100] It can be seen from Table 4 that the copper inhibitor obtained by silanization modification of nanocellulose by mixing two different mercaptosilane solutions at a ratio of 1:1 still has significant targeting. 3-Mercaptopropyltrimethoxysilane was used to modify hemicellulose and hemicellulose-polylactic acid composite lactose, respectively, and the inhibitor obtained had a significant inhibitory effect on copper minerals and a strong inhibitory ability on copper.

[0101] In summary, the present application provides a method for preparing and applying a copper-sulfur separation inhibitor for flotation removal of copper from copper-containing gold concentrate, which belongs to the technical field of mineral processing agents. The present application adds a mercaptosilane solution to an acidic suspension of polysaccharide low-molecular biomass compounds, first performs preliminary modification under stirring, and then further reacts it to completion by heating, thereby using silanization treatment to change the functional groups on the surface of the polysaccharide low-molecular biomass compounds, so that the prepared copper-sulfur separation inhibitor has a strong selective inhibitory effect on copper minerals. The copper-sulfur separation inhibitor prepared in the present application is applied to the flotation removal of copper from copper-containing gold concentrate, and flotation can be performed in a neutral or weakly acidic environment, and a small amount of copper-sulfur separation inhibitor can be used to effectively remove copper minerals from copper-containing gold concentrate, thereby achieving copper removal from copper-containing gold concentrate in a simple and efficient manner, and obtaining a low-copper gold concentrate with a higher gold grade at a higher gold recovery rate, which has a high practical application value.

[0102] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and the embodiments having the same structure as the technical idea and exerting the same effect within the scope of the technical solution of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the main purpose of the present application, various modifications that can be thought of by those skilled in the art to the embodiments and other methods of combining some of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. A method for preparing a copper-sulfur separation inhibitor for flotation removal of copper from copper-containing gold concentrate, characterized in that: The steps include: S1. preparing a polysaccharide low molecular weight biomass compound suspension and a mercaptosilane solution respectively; S2. adding a pH regulator to the polysaccharide low molecular weight biomass compound suspension to prepare an acidic polysaccharide low molecular weight biomass compound suspension; S3. adding the mercaptosilane solution to the acidic polysaccharide low molecular weight biomass compound suspension, stirring thoroughly, to obtain a preliminary modified polysaccharide low molecular weight biomass compound suspension; S4. The preliminarily modified polysaccharide low molecular weight biomass compound suspension is subjected to a heating treatment, and after the reaction is complete, the product is washed and dried to obtain a copper-sulfur separation inhibitor.

2. The method for preparing the copper-sulfur separation inhibitor for flotation removal of copper from copper-containing gold concentrate according to claim 1, characterized in that: In step S1, the polysaccharide low molecular weight biomass compound includes one or more of nanocellulose, hemicellulose, and hemicellulose-polylactic acid complex polysaccharide; the mercaptosilane includes one or more of 3-mercaptopropyltrimethoxysilane and γ-mercaptopropyltriethoxysilane.

3. The method for preparing the copper-sulfur separation inhibitor for flotation removal of copper from copper-containing gold concentrate according to claim 1, characterized in that: In step S1, the mass concentration of the polysaccharide low molecular weight biomass compound suspension is 0.1% to 5%, and the mass concentration of the mercaptosilane solution is 10% to 20%.

4. The method for preparing the copper-sulfur separation inhibitor for flotation removal of copper from copper-containing gold concentrate according to claim 1, characterized in that: In step S2, the pH value of the acidic polysaccharide low molecular weight biomass compound suspension is 3-5.

5. The method for preparing the copper-sulfur separation inhibitor for flotation removal of copper from copper-containing gold concentrate according to claim 1, characterized in that: In step S3, the mass of the mercaptosilane in the added mercaptosilane solution is 0.5 to 1.5 times the solid mass of the polysaccharide low molecular weight biomass compound in the acidic polysaccharide low molecular weight biomass compound suspension.

6. The method for preparing the copper-sulfur separation inhibitor for flotation removal of copper from copper-containing gold concentrate according to claim 1, characterized in that: In step S4, during the heating treatment, the heating temperature is 60-100° C. and the heating time is 3-5 hours.

7. An application method of a copper-sulfur separation inhibitor for flotation removal of copper from copper-containing gold concentrate, characterized in that: The copper-sulfur separation inhibitor prepared by the preparation method according to any one of claims 1 to 6 is applied to the flotation and copper removal process of copper-gold concentrate, comprising the following steps: After grinding the copper-gold concentrate, it is prepared into slurry; dissolving the copper-sulfur separation inhibitor in water to prepare an inhibitor suspension; The pH value of the slurry is adjusted to 6-7, and then the inhibitor suspension is added. After sufficient stirring, a collector and a frother are added to perform flotation operations to obtain high-copper-gold concentrate and low-copper-gold concentrate.

8. The method for applying the copper-sulfur separation inhibitor for flotation removal of copper from copper-containing gold concentrate according to claim 7, characterized in that: The grinding fineness of the grinding treatment is that particles with a particle size less than 400 mesh account for 60% to 90%; the mass concentration of the ore pulp is 25% to 35%.

9. The method for applying the copper-sulfur separation inhibitor for flotation removal of copper from copper-containing gold concentrate according to claim 7, characterized in that: The mass concentration of the copper-sulfur separation inhibitor in the inhibitor suspension is 1% to 10%.

10. The method for applying the copper-sulfur separation inhibitor for flotation removal of copper from copper-containing gold concentrate according to claim 7, characterized in that: The flotation operation includes one roughing operation and 1 to 4 scavenging operations; during the roughing operation, the dosage of the copper-sulfur separation inhibitor is 10 to 1000 g / t, and during each level of scavenging operation, the dosage of the copper-sulfur separation inhibitor is halved successively.

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