A zinc mineral depressant and a method for flotation separation of copper-zinc sulfide ore

Abstract

The present invention relates to the technical field of ore dressing, and in particular, to a zinc mineral depressant and a method for flotation separation of copper-zinc sulfide ore. The zinc mineral depressant includes oxidized konjac gum, which is obtained by oxidizing konjac gum through a TEMPO / NaBr / NaClO system. This oxidation system can selectively oxidize the primary hydroxyl group at the 6th position in konjac gum into a carboxyl group, and this carboxyl group can chelate with metal ions to avoid the activation of chalcopyrite due to Cu released during grinding or dissolution. 2+ It can also undergo strong chemical adsorption on the surface of sphalerite, significantly inhibiting the flotation of sphalerite. The present invention uses bis(hydroxymethyl)ethylthiourea and ethyl thionocarbamate as copper mineral collectors, and in combination with the zinc mineral depressant provided by the present invention for the flotation separation of copper-zinc sulfide ore, can significantly expand the floatability difference between copper minerals and zinc minerals in copper-zinc sulfide ore, and effectively reduce the zinc grade in copper concentrate during the copper-zinc separation process.

Description

Technical Field

[0001] The present invention relates to the technical field of ore dressing, and more particularly, to a zinc mineral depressant and a method for flotation separation of copper-zinc sulfide ore. Background Art

[0002] Mineral resources are the material basis for social and economic development and play a crucial role in social and economic activities. Among them, copper and zinc have wide applications in fields such as electronics, chemical industry, military, automotive, construction, shipbuilding, and light industry due to their unique physical and chemical properties, and are important mineral resources indispensable in modern industry and life. Chalcopyrite and sphalerite are the most important sources of copper and zinc, and these two ores often occur closely symbiotically in nature and are difficult to separate. Currently, flotation is the most effective copper-zinc ore separation technology. However, during the grinding process, fluid inclusions in chalcopyrite are destroyed and a large amount of Cu 2+ is released, which will significantly activate sphalerite, reduce the difference in floatability between chalcopyrite and sphalerite, and exacerbate the difficulty of copper-zinc flotation separation.

[0003] In order to achieve efficient flotation separation of copper-zinc sulfide ore, it is necessary to add a depressant to selectively reduce the surface hydrophobicity of a certain mineral. Since the natural floatability of chalcopyrite is better than that of sphalerite, the flotation process of depressing zinc and floating copper is mostly adopted in production. Therefore, the research and development of sphalerite depressants has always been the core in the flotation separation of copper and zinc. Sphalerite depressants can be mainly divided into two categories: inorganic depressants and organic depressants. Inorganic depressants such as zinc sulfate, sulfite, sulfate, cyanide, pyrophosphate, and metaphosphate have been widely used in industrial production practice in the past. However, these inorganic depressants have problems such as large dosage, serious environmental pollution, and great harm to the human body.

[0004] Chinese Patent Application CN115894318A discloses a preparation method and application of a copper-zinc separation depressant zinc N-methoxypropyl dithiocarbamate, which can effectively inhibit sphalerite and reduce the zinc intercontent in copper concentrate. However, the preparation method of this reagent is complex, the cost is high, and it is difficult to promote and apply.

[0005] Chinese Patent Application CN101428250A discloses a beneficiation method for copper-zinc separation, which uses a depressant composed of lime, sodium sulfide, zinc sulfate, and sodium sulfite, and can solve the problem of excessive zinc in copper concentrate or excessive copper in zinc concentrate. However, the dosage of this reagent is large and the environmental pollution is serious, which does not meet the development requirements of the "dual carbon" strategy. Therefore, it is crucial to develop an environmentally friendly and efficient zinc mineral depressant and a method for copper-zinc flotation separation.

[0006] In view of this, the present invention is specifically proposed. Summary of the Invention

[0007] The first object of the present invention is to provide a zinc mineral depressant, which includes TEMPO (2,2,6,6-tetramethylpiperidine-1-oxy) / NaBr / NaClO system oxidized konjac glucomannan. The TEMPO / NaBr / NaClO system can selectively oxidize the primary hydroxyl group at the 6th position in konjac glucomannan to a carboxyl group. The carboxyl group at this position has strong activity. On the one hand, it can chelate with metal ions to avoid the activation of sphalerite by Cu released due to grinding or dissolution of chalcopyrite. 2+ On the other hand, it can undergo strong chemical adsorption on the surface of sphalerite, significantly inhibiting the flotation of sphalerite.

[0008] The second object of the present invention is to provide a method for flotation separation of copper-zinc sulfide ores, which uses the above-mentioned zinc mineral depressant for flotation separation.

[0009] In order to achieve the above objects of the present invention, the following technical solutions are specifically adopted:

[0010] A zinc mineral depressant includes oxidized konjac glucomannan, and the oxidized konjac glucomannan is obtained by oxidizing konjac glucomannan with the TEMPO / NaBr / NaClO system.

[0011] Preferably, the preparation method of the oxidized konjac glucomannan includes the following steps:

[0012] S1. Mix the konjac glucomannan, TEMPO, NaBr and water, stir and dissolve them under light-shielded conditions, and then add an alkali to adjust the pH value.

[0013] S2. Add NaClO to the solution with adjusted pH in step S1 for reaction, and add an alkali during the reaction to maintain the pH value stable.

[0014] S3. After the reaction is completed, add ethanol to the reaction system, add an acid to adjust the pH value, and then carry out separation and purification to remove by-products and salts.

[0015] S4. Evaporate and concentrate the material obtained after the separation and purification, carry out solid-liquid separation and drying to obtain the oxidized konjac glucomannan.

[0016] Preferably, in step S1, the mass ratio of the konjac glucomannan, the TEMPO and the NaBr is 100:3 - 5:30 - 40.

[0017] Preferably, in step S1, the concentration of the konjac glucomannan is 5 - 20 g / L.

[0018] Preferably, in step S1, the pH value adjusted by adding the alkali is 9 - 11.

[0019] Preferably, in step S2, the mass ratio of the konjac glucomannan and the NaClO is 10:3 - 12.

[0020] Preferably, in step S2, the reaction time is 2 - 4 h.

[0021] Preferably, in step S2, the pH value during the reaction process is 9 - 11.

[0022] Preferably, in step S3, the mass concentration of the ethanol is 90% - 99%, and the ratio of the addition amount of the ethanol to the water usage amount in step S1 is 0.5 - 2 mL / L.

[0023] Preferably, in step S3, the pH value after adding the acid for adjustment is 4 - 5.

[0024] Preferably, in step S3, the separation and purification are carried out by dialysis.

[0025] A flotation separation method for copper - zinc sulfide ore, which uses a zinc mineral depressant and a copper mineral collector for flotation separation;

[0026] Among them, the zinc mineral depressant is the zinc mineral depressant described in any one of the foregoing embodiments; the copper mineral collector includes bis(hydroxymethyl)ethylthiourea and ethyl thionocarbamate.

[0027] Preferably, by mass parts, in the copper mineral collector, bis(hydroxymethyl)ethylthiourea is 6 - 8 parts, and ethyl thionocarbamate is 2 - 4 parts.

[0028] Preferably, the flotation separation method for copper - zinc sulfide ore includes the following steps:

[0029] S1. Crushing and grinding the copper - zinc sulfide ore to obtain a flotation pulp;

[0030] S2. Adding the copper mineral collector, the zinc mineral depressant and a foaming agent to the flotation pulp for rough flotation separation of copper and zinc to obtain a rough concentrate and a rough tailing;

[0031] S3. Adding the zinc mineral depressant to the rough concentrate for cleaning flotation separation of copper and zinc to obtain a copper concentrate and a cleaning middling;

[0032] Adding the copper mineral collector and a foaming agent to the rough tailing for scavenging flotation separation of copper and zinc to obtain a scavenging middling and a tailing.

[0033] Preferably, in step S1, the copper grade in the copper - zinc sulfide ore is 0.5% - 2%, and the zinc grade is 0.5% - 3%.

[0034] Preferably, in step S1, the fineness of the grinding is that - 0.074 mm accounts for 80% - 95%.

[0035] Preferably, in step S1, the mass concentration of the pulp is 27%-35%.

[0036] Preferably, in step S2, the dosage of the copper mineral collector is 60-150 g / t.

[0037] Preferably, in step S2, the dosage of the zinc mineral depressant is 400-800 g / t.

[0038] Preferably, in step S2, the dosage of the frother is 60-110 g / t.

[0039] Preferably, in step S3, the number of cleaning times is 2-4 times.

[0040] Preferably, in step S3, the dosage of the zinc mineral depressant for each cleaning is 100-350 g / t.

[0041] Preferably, in step S3, the number of scavenging times is 2-5 times.

[0042] Preferably, in step S3, the dosage of the copper mineral collector for each scavenging is 20-90 g / t.

[0043] Preferably, in step S3, the dosage of the frother for each scavenging is 10-50 g / t.

[0044] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0045] (1) The zinc mineral depressant provided by the present invention is obtained by selective oxidation modification of konjac gum. Konjac gum itself is a natural macromolecular agent derived from plants and biodegradable, with relatively low raw material costs and being non-toxic and harmless. The TEMPO / NaBr / NaClO system can selectively oxidize the primary hydroxyl group at the 6th position in konjac gum into a carboxyl group. On the one hand, this carboxyl group can chelate with metal ions to avoid the activation of sphalerite by Cu released due to grinding or dissolution of chalcopyrite. On the other hand, it can undergo strong chemical adsorption on the surface of sphalerite, significantly inhibiting the flotation of sphalerite. In oxidized konjac gum, the carboxyl group at the 6th position has strong activity, and oxidizing the hydroxyl group at the 6th position into a carboxyl group by selective oxidation has a better inhibitory effect. 2+ (2) The alkyl chain of the copper mineral collector used in the present invention is short and the polar group is strong, which has a strong selective effect on chalcopyrite and can promote the flotation separation of chalcopyrite and sphalerite.

[0046] (2) The copper mineral collector adopted by the invention has a short alkyl chain and a strong polar group, and has a strong selective action on chalcopyrite, which can promote the flotation separation of chalcopyrite and sphalerite.

[0047] (3) The zinc mineral depressant in the present invention can selectively adsorb on the surface of zinc minerals, without affecting the adsorption of the copper mineral collector on the surface of copper minerals. When used in combination with the copper mineral collector provided by the present invention, it can significantly expand the floatability difference between copper minerals and zinc minerals in copper-zinc sulfide ores, and effectively reduce the zinc grade in copper concentrate during the copper-zinc separation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0049] Figure 1 It is a flow chart of the flotation separation of copper-zinc sulfide ore provided by an embodiment of the present invention. SPECIFIC EMBODIMENTS

[0050] The following will clearly and completely describe the technical solutions of the present invention in combination with specific embodiments. However, those skilled in the art will understand that the described embodiments are some embodiments of the present invention, rather than all embodiments, and are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention. For those conditions not specified in the embodiments, they are carried out according to conventional conditions or the conditions recommended by the manufacturer. For the reagents or instruments not specified for the manufacturer, they are all conventional products that can be obtained through commercial purchase.

[0051] The first aspect of the present invention provides a zinc mineral depressant, including oxidized konjac gum, which is obtained by oxidizing konjac gum through a TEMPO / NaBr / NaClO system.

[0052] The present invention uses konjac gum as a raw material, which is of plant origin, biodegradable, with relatively low raw material cost, and non-toxic and harmless. The TEMPO / NaBr / NaClO oxidation system can selectively oxidize the primary hydroxyl group at the 6th position in konjac gum to a carboxyl group. The carboxyl group at this position has strong activity. On the one hand, it can complex with metal ions to avoid the activation of sphalerite by Cu released due to grinding or dissolution of chalcopyrite. 2+ On the other hand, it can undergo strong chemical adsorption with the surface of sphalerite, significantly inhibiting the flotation of sphalerite, and having an excellent inhibitory effect on zinc minerals, and can be used for the flotation separation of zinc-containing minerals.

[0053] In some specific embodiments of the present invention, the preparation method of oxidized konjac glucomannan specifically includes the following steps:

[0054] S1. Mix konjac glucomannan, TEMPO, NaBr and water, stir and dissolve them under dark and room temperature conditions, and then add an alkali to adjust the pH value.

[0055] S2. Add NaClO to the solution with adjusted pH in step S1 for reaction, and add an alkali during the reaction to maintain the stability of the pH value.

[0056] S3. After the reaction is completed, add ethanol to the reaction system, add an acid to adjust the pH value, and then carry out separation and purification to remove by-products and salts.

[0057] S4. Evaporate and concentrate the material obtained after separation and purification, carry out solid-liquid separation and drying to obtain the oxidized konjac glucomannan.

[0058] In some specific embodiments of the present invention, in step S1, the mass ratio of konjac glucomannan, TEMPO and NaBr is 100:3-5:30-40. For example, it can be any value among 100:3:30, 100:3:35, 100:3:40, 100:4:30, 100:4:35, 100:4:40, 100:5:30, 100:5:35, 100:5:40 or a range value composed of any two of these values.

[0059] In some specific embodiments of the present invention, in step S1, in the solution obtained by mixing konjac glucomannan, TEMPO, NaBr and water, the concentration of konjac glucomannan is 5-20 g / L. For example, it can be any value among 5 g / L, 10 g / L, 15 g / L, 20 g / L or a range value composed of any two of these values; if the concentration is too low, the concentration of the product after the reaction is low, and the cost of evaporating and concentrating to obtain the oxidized konjac glucomannan solid in the later stage is relatively high. If the concentration is too high, the solution is too viscous, which is not conducive to the later separation and purification. Therefore, the concentration of konjac glucomannan needs to be reasonably controlled during the reaction.

[0060] In some specific embodiments of the present invention, in step S1, the pH value adjusted by adding an alkali is 9-11. For example, the pH value can be any value among 9, 9.5, 10, 10.5, 11 or a range value composed of any two of these values; as an example, the alkali used to adjust the pH can be NaOH.

[0061] In some specific embodiments of the present invention, in step S2, the dosage of NaClO is measured according to the mass ratio of konjac gum to NaClO being 10:3 - 12. For example, the mass ratio of konjac gum to NaClO can be any point value among 10:3, 10:4, 10:5, 10:6, 10:7, 10:8, 10:9, 10:10, 10:11, 10:12 or a range value composed of any two point values; if the dosage of NaClO is too small, the oxidation is incomplete, and it is difficult to oxidize the hydroxyl group at the 6th position of konjac gum into a carboxyl group, and the molecular weight of the oxidized konjac gum is large, resulting in a poor inhibitory effect on zinc minerals. If the dosage of NaClO is too much, the cost is high, and it will increase the difficulty of separation and purification.

[0062] In some specific embodiments of the present invention, in step S2, NaClO is added in the form of a solution, and the mass concentration of the NaClO solution is 3% - 15%. For example, it can be any point value among 3%, 5%, 8%, 10%, 12%, 18% or a range value composed of any two point values.

[0063] In some specific embodiments of the present invention, in step S2, the reaction time is 2 - 4 h. For example, it can be any point value among 2 h, 2.5 h, 3 h, 3.5 h, 4 h or a range value composed of any two point values.

[0064] In some specific embodiments of the present invention, in step S2, the pH value during the reaction process is 9 - 11. For example, it can be any point value among 9, 9.5, 10, 10.5, 11 or a range value composed of any two point values; as an example, the base added during the reaction process can be NaOH.

[0065] In some specific embodiments of the present invention, in step S3, the mass concentration of the ethanol used is 90% - 99%. For example, it can be any point value among 90%, 92%, 95%, 97%, 99% or a range value composed of any two point values; the dosage ratio of the added ethanol to the water dosage in step S1 is 0.5 - 2 mL / L. For example, it can be any point value among 0.5 mL / L, 0.8 mL / L, 1 mL / L, 1.2 mL / L, 1.5 mL / L, 1.8 mL / L, 2 mL / L or a range value composed of any two point values.

[0066] In some specific embodiments of the present invention, in step S3, the pH value after adding acid for adjustment is 4 - 5. For example, it can be any point value among 4, 4.2, 4.5, 4.8, 5 or a range value composed of any two point values; the purpose of adding ethanol and acid is to facilitate separation and purification. As an example, the acid used to adjust the pH can be HCl.

[0067] In some specific embodiments of the present invention, in step S3, dialysis separation and purification are carried out by using a dialysis bag; as an example, the dialysis bag used can be a 500 Da dialysis bag.

[0068] In some specific embodiments of the present invention, in step S4, the solid-liquid separation method is centrifugal separation.

[0069] In some specific embodiments of the present invention, the average molecular weight of the konjac glucomannan used is 200,000 - 800,000. For example, the molecular weight of the konjac glucomannan can be any value among 200,000, 300,000, 400,000, 500,000, 600,000, 700,000, 800,000 or any range value composed of any two of these values.

[0070] The second aspect of the present invention provides a method for flotation separation of copper-zinc sulfide ore, which uses a zinc mineral depressant and a copper mineral collector for flotation separation;

[0071] Among them, the zinc mineral depressant is the zinc mineral depressant described in any one of the foregoing embodiments; the copper mineral collector includes bis(hydroxymethyl)ethylthiourea and ethyl thionocarbamate.

[0072] The zinc mineral depressant used in the present invention can selectively adsorb on the surface of zinc minerals, without affecting the adsorption of the copper mineral collector on the surface of copper minerals, and the alkyl chain of the copper mineral collector used is short and the polar group is strong, having a strong selective effect on chalcopyrite. The zinc mineral depressant and the copper mineral collector in the present invention are used in combination, which can significantly expand the difference in floatability between copper minerals and zinc minerals in copper-zinc sulfide ore, and effectively reduce the zinc grade in copper concentrate during the copper-zinc separation process.

[0073] In some specific embodiments of the present invention, by mass fraction, in the copper mineral collector, the mass fraction of bis(hydroxymethyl)ethylthiourea is 6 - 8 parts. For example, it can be any value among 6 parts, 6.5 parts, 7 parts, 7.5 parts, 8 parts or any range value composed of any two of these values; the mass fraction of ethyl thionocarbamate is 2 - 4 parts. For example, it can be any value among 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts or any range value composed of any two of these values.

[0074] As Figure 1 shown, in some specific embodiments of the present invention, the method for flotation separation of the copper-zinc sulfide ore includes the following steps:

[0075] S1. Crushing and grinding the copper-zinc sulfide ore (raw ore) to obtain a flotation pulp;

[0076] S2. Adding the copper mineral collector, the zinc mineral depressant and a foaming agent to the flotation pulp for rough flotation separation of copper and zinc to obtain a rough concentrate and a rough tailing;

[0077] S3. Add a zinc mineral depressant to the rougher concentrate for the cleaning separation of copper and zinc to obtain copper concentrate and cleaned middlings;

[0078] Add a copper mineral collector and a frother to the rougher tailings for the scavenging separation of copper and zinc to obtain scavenged middlings and tailings.

[0079] Using the zinc mineral depressant and copper mineral collector provided by the present invention in combination with a frother for rougher, cleaner, and scavenger flotation, the obtained copper concentrate has a high copper recovery rate, high grade, low zinc grade in the copper concentrate, and good copper-zinc separation effect; in some specific embodiments, the cleaned middlings obtained in the cleaning process and the scavenged middlings obtained in the scavenging process can be respectively returned to the rougher step to repeat the flotation separation.

[0080] In some specific embodiments of the present invention, in step S1, the copper grade in the copper-zinc sulfide ore is 0.5% - 2%, and the zinc grade is 0.5% - 3%.

[0081] In some specific embodiments of the present invention, in step S1, the fineness after grinding is 80% - 95% passing - 0.074mm. For example, it can be any single value or a range value composed of any two of 80%, 82%, 85%, 87%, 90%, 92%, 95%; on the one hand, the copper-zinc sulfide ore needs to achieve effective monomer dissociation through crushing and grinding, and on the other hand, the mass of minerals with a particle size of - 0.074mm in the pulp entering the flotation should account for 80% - 95%. At this grinding fineness, it is beneficial for the mineral particles to interact with the reagents to form stable mineralized foam.

[0082] In some specific embodiments of the present invention, in step S1, water can be added after grinding to make pulp, or water can be added during grinding for wet grinding to obtain pulp, and the mass concentration of the obtained pulp is 27% - 35%. For example, it can be any single value or a range value composed of any two of 27%, 29%, 30%, 32%, 34%, 35%.

[0083] In some specific embodiments of the present invention, in step S2, the addition amount of the copper mineral collector is 60 - 150g / t. For example, it can be any single value or a range value composed of any two of 60g / t, 70g / t, 80g / t, 90g / t, 100g / t, 110g / t, 120g / t, 130g / t, 140g / t, 150g / t.

[0084] In some specific embodiments of the present invention, in step S2, the addition amount of the zinc mineral depressant is 400 - 800g / t. For example, it can be any single value or a range value composed of any two of 400g / t, 500g / t, 600g / t, 700g / t, 800g / t.

[0085] In some specific embodiments of the present invention, in step S2, the addition amount of the foaming agent is 60-110 g / t. For example, it can be any value among 60 g / t, 70 g / t, 80 g / t, 90 g / t, 100 g / t, 110 g / t or a range value composed of any two of these values.

[0086] In some specific embodiments of the present invention, in step S3, the number of scavenging times is 2-4 times. For example, it can be 2 times, 3 times or 4 times.

[0087] In some specific embodiments of the present invention, in step S3, during each scavenging process, the addition amount of the zinc mineral inhibitor is 100-350 g / t. For example, it can be any value among 100 g / t, 130 g / t, 150 g / t, 180 g / t, 200 g / t, 230 g / t, 260 g / t, 300 g / t, 350 g / t or a range value composed of any two of these values.

[0088] In some specific embodiments of the present invention, in step S3, the number of cleaning times is 2-5 times. For example, it can be 2 times, 3 times, 4 times or 5 times.

[0089] In some specific embodiments of the present invention, in step S3, during each cleaning process, the addition amount of the copper mineral collector is 20-90 g / t. For example, it can be any value among 20 g / t, 30 g / t, 40 g / t, 50 g / t, 60 g / t, 70 g / t, 80 g / t, 90 g / t or a range value composed of any two of these values.

[0090] In some specific embodiments of the present invention, in step S3, during each cleaning process, the addition amount of the foaming agent is 10-50 g / t. For example, it can be any value among 10 g / t, 15 g / t, 20 g / t, 30 g / t, 40 g / t, 50 g / t or a range value composed of any two of these values.

[0091] In some specific embodiments of the present invention, the foaming agent in step S2 and the foaming agent in step S3 are each independently selected from at least one of methyl isobutyl carbinol and pine oil.

[0092] In the present invention, the addition amount of the reagent is relative to the amount of the original ore.

[0093] The following will, with reference to specific examples, elaborate in detail some embodiments of the present invention. The raw material substances used in the examples can be obtained through commercial purchase without special instructions.

[0094] Example 1

[0095] This embodiment provides a zinc mineral inhibitor, which is TEMPO / NaBr / NaClO system oxidized konjac gum. The preparation method includes the following steps:

[0096] S1. Weigh 10 g of konjac gum, 0.3 g of TEMPO, and 3 g of NaBr into a flask, add 1 L of ultrapure water, stir well to dissolve, and then add NaOH solution to adjust the pH to 10;

[0097] S2. Add 20 ml of 20% NaClO solution to the solution obtained in step S1 and react for 2 h. At the same time, continuously add NaOH solution to keep the pH value around 10;

[0098] S3. After the reaction is completed, add 0.8 ml of 95% ethanol to the flask, then add HCl solution to adjust the pH value to 5, and place it in a 500 Da dialysis bag for dialysis for 2 d;

[0099] S4. Evaporate and concentrate the dialyzed solution and centrifuge it, and take the lower layer solution for drying to obtain the product.

[0100] Example 2

[0101] This embodiment provides a zinc mineral inhibitor, which is TEMPO / NaBr / NaClO system oxidized konjac gum. The preparation method includes the following steps:

[0102] S1. Weigh 10 g of konjac gum, 0.4 g of TEMPO, and 3.5 g of NaBr into a flask, add 1 L of ultrapure water, stir well to dissolve, and then add NaOH solution to adjust the pH to 10;

[0103] S2. Add 30 ml of 20% NaClO solution to the solution obtained in step S1 and react for 3 h. At the same time, continuously add NaOH solution to keep the pH value around 10;

[0104] S3. After the reaction is completed, add 1 ml of 95% ethanol to the flask, then add HCl solution to adjust the pH value to 5, and place it in a 500 Da dialysis bag for dialysis for 2 d;

[0105] S4. Evaporate and concentrate the dialyzed solution and centrifuge it, and take the lower layer solution for drying to obtain the product.

[0106] Example 3

[0107] This embodiment provides a zinc mineral inhibitor, which is TEMPO / NaBr / NaClO system oxidized konjac gum. The preparation method includes the following steps:

[0108] S1. Weigh 10 g of konjac gum, 0.5 g of TEMPO, and 4 g of NaBr into a flask, add 1 L of ultrapure water, stir well to dissolve, and then add NaOH solution to adjust the pH to 10;

[0109] S2. Add 40 ml of 20% NaClO solution to the solution obtained in step S1 and react for 4 h. At the same time, continuously add NaOH solution to maintain the pH value around 10;

[0110] S3. After the reaction is completed, add 1.2 ml of 95% ethanol to the flask, then add HCl solution to adjust the pH value to 5, and dialyze in a 500 Da dialysis bag for 2 d;

[0111] S4. Evaporate and concentrate the dialyzed solution and centrifuge it, and take the lower-layer solution for drying to obtain the product.

[0112] Example 4

[0113] Use the zinc mineral depressant prepared in Example 1 for the flotation separation of copper-zinc sulfide ore;

[0114] The copper mineral collector is composed of 6 parts of bis(hydroxymethyl)ethylthiourea and 4 parts of ethyl thionocarbamate by mass;

[0115] The test ore is copper-zinc sulfide ore from a certain place in Inner Mongolia, containing 0.69% copper and 1.12% zinc. Copper in the ore mainly exists in the form of chalcopyrite, and zinc mainly exists in the form of sphalerite. In addition, the ore also contains metal minerals such as pyrite, arsenopyrite, and pyrrhotite. The gangue minerals are mainly quartz, calcite, feldspar, etc. The ore properties are complex, the particle size distribution is fine, and the flotation separation is difficult.

[0116] The flotation separation steps of copper-zinc sulfide ore are as follows:

[0117] S1. Take 500 g of the crushed raw ore, add water and grind it in a ball mill (wet grinding) to obtain the flotation pulp, control the grinding fineness to -0.074 mm accounting for 92%, and the mass concentration of the pulp is 28%;

[0118] S2. Take out the pulp ground in the ball mill, put it into a flotation machine, and sequentially add the copper mineral collector, zinc mineral depressant, and foaming agent (methyl isobutyl carbinol) for rough separation of copper and zinc to obtain the rough concentrate and rough tailings; among them, the dosage of the copper mineral collector is 120 g / t, the dosage of the zinc mineral depressant is 800 g / t, and the dosage of the foaming agent is 90 g / t;

[0119] S3. Add a zinc mineral depressant to the rougher concentrate for the cleaning separation of copper and zinc. The cleaning is carried out three times, and the middlings obtained from the first, second, and third cleaning are returned to the copper-zinc separation rougher operation. Among them, the dosage of the zinc mineral depressant in the first cleaning is 300 g / t, the dosage in the second cleaning is 200 g / t, and the dosage in the third cleaning is 150 g / t.

[0120] Add a copper mineral collector and a frother (methyl isobutyl carbinol) to the rougher tailings for the scavenging separation of copper and zinc. The scavenging is carried out three times, and the middlings obtained from the first, second, and third scavenging are returned to the copper-zinc separation rougher operation. Among them, the dosage of the copper mineral collector in the first scavenging is 60 g / t, and the dosage of the frother is 40 g / t; the dosage of the copper mineral collector in the second scavenging is 30 g / t, and the dosage of the frother is 20 g / t; the dosage of the copper mineral collector in the third scavenging is 30 g / t, and the dosage of the frother is 15 g / t.

[0121] Example 5

[0122] Use the zinc mineral depressant prepared in Example 2 for the flotation separation of copper-zinc sulfide ores.

[0123] The copper mineral collector is composed of 7 parts of bis(hydroxymethyl)ethylthiourea and 3 parts of ethyl thionocarbamate by mass.

[0124] The test ore is copper-zinc sulfide ore from a certain place in Guangxi, containing 0.60% copper and 0.52% zinc. The metal minerals in the ore are mainly marmatite, chalcopyrite, pyrite, marcasite, and arsenopyrite. The copper-zinc sulfide ore is closely symbiotic with a relatively fine dissemination size.

[0125] The flotation separation steps of the copper-zinc sulfide ore are as follows:

[0126] S1. Take 500 g of the crushed raw ore, add water and grind it in a ball mill (wet grinding) to obtain a flotation pulp. Control the grinding fineness to be 85% passing -0.074 mm, and the mass concentration of the pulp to be 30%.

[0127] S2. Take out the pulp ground in the ball mill, put it into a flotation machine, and sequentially add a copper mineral collector, a zinc mineral depressant, and a frother (methyl isobutyl carbinol) for the rougher separation of copper and zinc to obtain a rougher concentrate and rougher tailings. Among them, the dosage of the copper mineral collector is 80 g / t, the dosage of the zinc mineral depressant is 600 g / t, and the dosage of the frother is 80 g / t.

[0128] S3. Add a zinc mineral depressant to the rougher concentrate for the selective separation of copper and zinc. The selective separation is carried out three times, and the middlings obtained from the first, second, and third selective separations are returned to the copper-zinc rougher flotation operation. Among them, the dosage of the zinc mineral depressant in the first selective separation is 200 g / t, the dosage in the second selective separation is 100 g / t, and the dosage in the third selective separation is 100 g / t.

[0129] Add a copper mineral collector and a frother (methyl isobutyl carbinol) to the rougher tailings for the scavenging flotation of copper and zinc. The scavenging flotation is carried out three times, and the middlings obtained from the first, second, and third scavenging flotation are returned to the copper-zinc rougher flotation operation. Among them, the dosage of the copper mineral collector in the first scavenging flotation is 50 g / t, and the dosage of the frother is 30 g / t; the dosage of the copper mineral collector in the second scavenging flotation is 25 g / t, and the dosage of the frother is 20 g / t; the dosage of the copper mineral collector in the third scavenging flotation is 20 g / t, and the dosage of the frother is 15 g / t.

[0130] Example 6

[0131] Use the zinc mineral depressant prepared in Example 3 for the flotation separation of copper-zinc sulfide ores.

[0132] The copper mineral collector is composed of 8 parts of bis(hydroxymethyl)ethylthiourea and 2 parts of ethyl thionocarbamate by mass.

[0133] The test ore is a copper-zinc sulfide ore from a certain place in Yunnan, containing 1.98% copper and 1.36% zinc. The main metal minerals in the ore are chalcopyrite, sphalerite, pyrite, pyrrhotite, etc.; in addition, there are also a small amount of bornite, chalcocite, malachite, hematite, galena, etc.; the main gangue minerals are quartz, feldspar, sericite, chlorite, etc.

[0134] The flotation separation steps of copper-zinc sulfide ores are as follows:

[0135] S1. Take 500 g of the crushed raw ore, add water and grind it in a ball mill (wet grinding) to obtain a flotation pulp. Control the grinding fineness to be 90% passing -0.074 mm, and the mass concentration of the pulp is 32%.

[0136] S2. Take out the pulp ground in the ball mill, put it into a flotation machine, and sequentially add a copper mineral collector, a zinc mineral depressant, and a frother (methyl isobutyl carbinol) for the rougher flotation of copper and zinc to obtain a rougher concentrate and rougher tailings. Among them, the dosage of the copper mineral collector is 100 g / t, the dosage of the zinc mineral depressant is 700 g / t, and the dosage of the frother is 80 g / t.

[0137] S3. Add zinc mineral inhibitor to the roughing concentrate to separate copper and zinc, the number of times of selection is three, and the selected middlings obtained from the first, second and third selections are returned to the copper and zinc separation roughing operation; wherein, the amount of zinc mineral inhibitor used in the first selection is 260g / t, the amount of zinc mineral inhibitor used in the second selection is 180g / t, and the amount of zinc mineral inhibitor used in the third selection is 130g / t;

[0138] Copper mineral collector and frother (methyl isobutyl carbinol) are added to the roughing tailings for copper-zinc separation scavenging. The scavenging times are three times, and the scavenged ore obtained from scavenging one, scavenging two and scavenging three are returned to the copper-zinc separation roughing operation; wherein, the amount of copper mineral collector in scavenging one is 65g / t, and the amount of frother is 35g / t; the amount of copper mineral collector in scavenging two is 35g / t, and the amount of frother is 20g / t; the amount of copper mineral collector in scavenging three is 30g / t, and the amount of frother is 15g / t.

[0139] Comparative Example 1

[0140] Comparative Example 1 is similar to Example 4, except that the zinc mineral inhibitor is replaced by an equal amount of zinc sulfate, the copper mineral collector is replaced by an equal amount of butyl xanthate, and the other conditions are the same as those of Example 1.

[0141] Comparative Example 2

[0142] Comparative Example 2 is similar to Example 4, except that the zinc mineral inhibitor is a mixture of konjac gum and NaClO, the amounts of konjac gum and NaClO are the same as those in Example 1, and the other flotation separation conditions are the same as those in Example 4.

[0143] Comparative Example 3

[0144] Comparative Example 3 is similar to Example 4, except that the di(hydroxymethyl)ethylenethiourea in the copper mineral collector is replaced with an equal amount of butyl xanthate, and the other conditions are the same as those in Example 4.

[0145] Comparative Example 4

[0146] Comparative Example 4 is similar to Example 5, except that the zinc mineral inhibitor is replaced with an equal amount of sodium sulfite, and the other conditions are the same as those of Example 5.

[0147] Comparative Example 5

[0148] Comparative Example 5 is similar to Example 5, except that the di(hydroxymethyl)ethylenethiourea in the copper mineral collector is replaced with an equal amount of butylammonium black medicine, and the other conditions are the same as those in Example 5.

[0149] Comparative Example 6

[0150] Comparative Example 6 is similar to Example 6, with the only difference being that the zinc mineral inhibitor is replaced with an equal amount of sodium sulfide, and the other conditions are the same as those in Example 6.

[0151] Comparative Example 7

[0152] Comparative Example 7 is similar to Example 6, with the only difference being that the bis(hydroxymethyl)ethylthiourea in the copper mineral collector is replaced with an equal amount of ethyl xanthate, and the other conditions are the same as those in Example 6.

[0153] Test Example

[0154] The yields, copper and zinc grades, and copper and zinc recovery rates of the copper concentrates and floating copper tailings obtained from Examples 4 - 6 and Comparative Examples 1 - 7 were respectively tested, and the test results are shown in Table 1.

[0155] Table 1

[0156]

[0157] It can be seen from the data in Table 1 that compared with Example 4, the yields of the copper concentrates obtained in Comparative Examples 1 and 2 increased, the copper grades and recovery rates decreased significantly, the yield of the copper concentrate obtained in Comparative Example 3 decreased, the copper grade decreased, and the copper recovery rate decreased significantly; compared with Example 5, the yield of the copper concentrate obtained in Comparative Example 4 increased, the copper grade and recovery rate decreased, the yield of the copper concentrate obtained in Comparative Example 5 decreased, and the copper grade and copper recovery rate decreased significantly; compared with Example 6, the yield of the copper concentrate obtained in Comparative Example 6 increased, the copper grade decreased significantly, the copper recovery rate decreased, the yield of the copper concentrate obtained in Comparative Example 7 decreased, the copper grade decreased, and the copper recovery rate decreased significantly. It can be seen from this that the methods of Examples 4, 5, and 6 of the present invention can separate copper and zinc in the raw ore more fully compared with the methods of Comparative Examples 1 - 3, Comparative Examples 4 - 5, and Comparative Examples 6 - 7 respectively. At the same time, although the yields of the copper concentrates obtained in Comparative Examples 1, 2, 4, and 6 increased, their grades and recovery rates decreased. This shows that compared with the inhibitors provided by the present invention, when using a mixture of zinc sulfate, konjac gum, and NaClO, sodium sulfite, and sodium sulfide as inhibitors, their selective inhibitory effect on zinc minerals is relatively weak, resulting in an increase in impurities in the concentrate. On the other hand, the yields of the copper concentrates obtained in Comparative Examples 3, 5, and 7, as well as the copper grades and recovery rates of the obtained copper concentrates, decreased. This shows that compared with the collectors provided by the present invention, when using butyl xanthate, ammonium dibutyl dithiophosphate, and ethyl xanthate as collectors, their collecting effect on copper minerals is relatively poor, and some copper minerals fail to be collected and are lost in the tailings.

[0158] Although the present invention has been illustrated and described with reference to specific embodiments, it should be understood that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it; those of ordinary skill in the art should understand that: without departing from the spirit and scope of the present invention, the technical solutions described in the foregoing embodiments may be modified, or some or all of the technical features may be equivalently replaced; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention; therefore, this means that all such replacements and modifications that fall within the scope of the present invention are included in the appended claims.

Claims

1. A method for flotation separation of copper-zinc sulfide ore, characterized in that, Flotation separation is carried out using a zinc mineral depressant and a copper mineral collector; the zinc mineral depressant includes oxidized konjac gum, and the oxidized konjac gum is obtained by oxidizing konjac gum through a TEMPO, NaBr, NaClO system; The preparation method of the oxidized konjac gum includes the following steps: S1. Mix the konjac gum, TEMPO, NaBr and water, stir and dissolve in the dark, and then add alkali to adjust the pH value; S2. Add NaClO to the solution with adjusted pH in step S1 for reaction, and add alkali during the reaction to maintain the pH value stable; S3. After the reaction is completed, add ethanol to the reaction system, add acid to adjust the pH value, and then carry out separation and purification to remove by-products and salts; S4. Evaporate and concentrate, solid-liquid separate and dry the material obtained after the separation and purification to obtain the oxidized konjac gum.

2. The flotation separation method of copper-zinc sulfide ore according to claim 1, characterized in that, In step S1, at least one of the following characteristics is satisfied: (1) The mass ratio of the konjac gum, the TEMPO and the NaBr is 100:3-5:30-40; (2) The concentration of the konjac gum is 5-20 g / L; (3) The pH value adjusted by adding the alkali is 9-11.

3. The flotation separation method of copper-zinc sulfide ore according to claim 1, wherein In step S2, at least one of the following characteristics is satisfied: (1) The mass ratio of the konjac gum and the NaClO is 10:3-12; (2) The reaction time is 2-4 h; (3) The pH value during the reaction process is 9-11.

4. The flotation separation method of copper-zinc sulfide ore according to claim 1, characterized in that, In step S3, at least one of the following characteristics is satisfied: (1) The mass concentration of the ethanol is 90%-99%, and the addition amount of the ethanol is in a ratio of 0.5-2 mL / L to the amount of water used in step S1; (2) The pH value adjusted by adding the acid is 4-5; (3) The separation and purification is carried out by dialysis.

5. The flotation separation method of copper-zinc sulfide ore according to claim 1, characterized in that, By mass, the copper mineral collector includes 6-8 parts of dimethylol ethylene thiourea and 2-4 parts of ethyl thionocarbamate.

6. The flotation separation method of copper-zinc sulfide ore according to claim 1, wherein The flotation separation method of the copper-zinc sulfide ore includes the following steps: S1. Crush and grind the copper-zinc sulfide ore to obtain a flotation pulp; S2. Add the copper mineral collector, the zinc mineral depressant and a frother to the flotation pulp for rough separation of copper and zinc to obtain a rough concentrate and a rough tailing; S3. Add the zinc mineral depressant to the rough concentrate for cleaning separation of copper and zinc to obtain a copper concentrate and a cleaning middling; Add the copper mineral collector and a frother to the rough tailing for scavenging separation of copper and zinc to obtain a scavenging middling and a tailing.

7. The flotation separation method of copper-zinc sulfide ore according to claim 6, characterized in that, In step S1, at least one of the following characteristics is satisfied: (1) The copper grade in the copper-zinc sulfide ore is 0.5%-2%, and the zinc grade is 0.5%-3%; (2) The fineness of the grinding is 80%-95% of -0.074 mm; (3) The mass concentration of the pulp is 27%-35%.

8. The flotation separation method of copper-zinc sulfide ore according to claim 6, characterized in that, In step S2, at least one of the following characteristics is satisfied: (1) The addition amount of the copper mineral collector is 60-150 g / t; (2) The addition amount of the zinc mineral depressant is 400-800 g / t; The dosage of the foaming agent is 60 - 110 g / t.

9. The flotation separation method of copper-zinc sulfide ore according to claim 6, wherein In step S3, at least one of the following characteristics is satisfied: (1) The number of times of the concentration is 2 - 4 times; (2) The dosage of the zinc mineral depressant added each time for the concentration is 100 - 350 g / t; (3) The number of times of the scavenging is 2 - 5 times; (4) The dosage of the copper mineral collector added each time for the scavenging is 20 - 90 g / t; (5) The dosage of the foaming agent added each time for the scavenging is 10 - 50 g / t.

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