Collector for fine-grained quartz ore and preparation method and application thereof

Abstract

The application provides a collector for fine-grained quartz ore and a preparation method and application thereof, and relates to the technical field of mineral flotation. Specifically, the preparation method of the collector in the application comprises the following steps: a mixture containing graphene and sodium oleate is subjected to cold plasma treatment, and the graphene and the sodium oleate are grafted to obtain the collector. The collector can be used for mineral flotation and can efficiently obtain high-purity quartz. Based on the performance of the graphene net and the corresponding functional groups of the grafted sodium oleate, the flocculation effect on fine-grained quartz is realized, so that the quartz can be efficiently collected, the problem that fine-grained quartz is difficult to collect and float due to a large free energy in the ore slurry during the flotation process is reduced, the flotation separation efficiency is improved, the separation index is improved, and the collector has a good application prospect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mineral flotation, in particular to a collector for micro-fine particle quartz ore and a preparation method and application thereof. BACKGROUND

[0002] With the continuous acceleration of industrialization and modernization process and the development of chip manufacturing industry, the demand for high-purity quartz in various fields has increased year by year; but due to the characteristics of the current quartz resources being poor, fine and mixed, it is inevitable that the ore and quartz are associated and difficult to separate. The abundance of quartz and a large number of silicate minerals in the earth's crust reaches more than 90%, and the current production of high-purity quartz presents the characteristics of coexistence of technical breakthrough and capacity expansion, but there are still some shortcomings; at the same time, the exploration of raw materials has made progress, and now many regions have found mineral resources similar to imported high-purity quartz deposits, which provides the possibility for raw material self-sufficiency. In addition, the production capacity of enterprises has gradually expanded, making the high-purity quartz sand industry enter the capacity construction period; in recent years, the production capacity of high-purity quartz sand projects that have been completed and put into production has reached 130,000 tons, while the annual output of high-purity quartz sand is only about 45,000 tons, and the output growth still lags behind the production capacity, but with the maturation of technology and the easing of raw material problems, the production capacity is expected to be further released.

[0003] Micro-fine particle quartz ore is a kind of complex and difficult-to-separate ore with complex mineral composition and dissemination relationship. At present, flotation process is usually used for such complex and difficult-to-separate ore, but due to the fact that the main gangue in the ore is quartz, feldspar and other brittle and easy-to-break minerals, which are prone to mudification during grinding process, resulting in a large amount of fine mud minerals dispersed in the ore slurry, which leads to the failure to obtain high-purity quartz products; on the other hand, due to the small specific surface area and high surface energy of micro-fine particle minerals, the adsorption of micro-fine particle gangue on minerals during flotation process leads to large dosage of reagents and low flotation recovery rate, and the high surface energy leads to large degree of freedom, which cannot effectively float with the foam, thus reducing the concentrate grade. In summary, due to the lack of effective separation technology and suitable flotation reagents, the effective recovery of quartz is seriously affected.

[0004] Therefore, the present application is proposed. SUMMARY

[0005] The first object of the present application is to provide a preparation method of a collector for micro-fine particle quartz ore, aiming at solving the problem of how to realize efficient separation of complex and difficult-to-separate micro-fine particle quartz.

[0006] The second object of the present application is to provide a collector.

[0007] The third object of the present application is to provide the application of the collector in a mineral flotation method.

[0008] In order to achieve the above objects of the present application, the following technical solutions are adopted:

[0009] A method for preparing a collector for fine-grained quartz ore, comprising the following steps:

[0010] A mixture comprising graphene and sodium oleate is subjected to cold plasma treatment to graft the graphene and the sodium oleate, thereby obtaining a collector.

[0011] Preferably, the mass ratio of the graphene and the sodium oleate is 1: (1-3).

[0012] Preferably, the cold plasma treatment comprises the following steps: first, placing the mixture in a vacuum state, and then adjusting to a working gas environment and electrifying to ionize the gas, so that the mixture is in a plasma environment and the reaction is continued for 5-10 minutes.

[0013] More preferably, the working gas comprises nitrogen, and the input amount of the working gas is 0.2-0.4 L / min.

[0014] More preferably, the electrification conditions comprise the following: using direct current, the voltage is 300-400 V, the current is 40-60 mA, and the power density is 40-60 W / cm 2 . 2 .

[0015] A collector is prepared by the method for preparing a collector for fine-grained quartz ore.

[0016] The collector is used in a mineral flotation method.

[0017] Preferably, the flotation recovery of fine-grained quartz ore by the collector comprises the following steps:

[0018] First, the pH of the ore slurry is adjusted to 9-11 by a pH adjuster, and then the collector and a second collector are added, the ore slurry is fully adjusted, and then flotation is performed, the flotation froth is scraped, and fine-grained quartz ore is obtained.

[0019] More preferably, the amount of the collector added is 40-80 mg / L based on the mass of the ore slurry, and the amount of the second collector added is 20-80 mg / L.

[0020] More preferably, the second collector comprises a fatty acid compound or a hydroxamic acid compound.

[0021] More preferably, after adjusting the pH of the ore slurry, the collector is first added and stirred for 2-4 minutes, then the second collector is added and stirred for 2-4 minutes, and then the flotation froth is scraped for 3-5 minutes until the fine-grained quartz ore is obtained.

[0022] Compared with the prior art, the present application has the following beneficial effects:

[0023] (1) The present application provides a collector for fine-grained quartz, which is prepared by grafting sodium oleate and graphene through cold plasma treatment, thereby obtaining modified graphene with grafted ester groups that has high selectivity for fine-grained quartz; meanwhile, in mineral flotation, based on the molecular association effect and bridging network aggregation performance of silicophilic flotation reagents, modified graphene is used as an auxiliary collector, and the network structure of the two kinds of composite collectors is used to bridge and aggregate fine-grained quartz and obtain larger particles, increase the apparent particle size of fine-grained quartz gangue particles, and further strengthen the collection of fine-grained quartz, reduce the problem of free collection of fine-grained quartz in the flotation process due to high free energy, improve the flotation separation efficiency and improve the separation index; it can also reduce the problem of water entrainment caused by high free energy of quartz in the flotation process, and improve the flotation recovery rate of quartz.

[0024] (2) The present application recovers high-purity quartz by flotation, reducing environmental pollution caused by quartz gangue in the field of flotation; no harmful chemicals are used in the flotation recovery process of the present application, and the reagents will naturally degrade after use, meeting environmental protection requirements. Traditional quartz flotation collectors in the field, such as anionic collectors such as oxidized paraffin soap, sodium dodecyl sulfonate, and sodium dodecyl sulfate, have poor selectivity for fine-grained quartz and cannot effectively float fine-grained gangue, so in order to increase the grade of quartz in the concentrate, the amount of reagents must be increased, which also leads to the discharge of metal minerals with quartz gangue into the tailings, further exacerbating environmental pollution; the collector of the present application can agglomerate fine-grained gangue without increasing the amount of reagents, which has important practical significance for improving the separation efficiency. DETAILED DESCRIPTION

[0025] The technical solutions of the present application will be described below in conjunction with specific embodiments, but those skilled in the art will understand that the following described embodiments are part of the embodiments of the present application, not all of the embodiments, and are only used to illustrate the present application, and should not be regarded as limiting the scope of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application. If the specific conditions are not specified in the embodiments, the conventional conditions or the conditions recommended by the manufacturer are used. If the reagents or instruments used are not specified by the manufacturer, they are all conventional products that can be purchased on the market. In addition, the terms "first", "second", "third" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance.

[0026] The first aspect of the present application is to provide a preparation method of a collector for fine-grained quartz ore, mainly comprising the following steps: subjecting a mixture containing graphene and sodium oleate to cold plasma treatment to graft the graphene and the sodium oleate, thereby obtaining a collector.

[0027] In the present application, the grafting treatment between the two raw materials is realized by cold plasma (Non-thermal Plasma); specifically, the cold plasma is a partially ionized gas containing active species such as high-energy electrons, ions, free radicals and excited-state molecules, which selectively breaks chemical bonds through cold plasma, so that high-energy electrons can accurately break specific chemical bonds while avoiding damage to non-target chemical bonds in sodium oleate; at the same time, the C=C bond in sodium oleate is lifted from the ground state to the excited state through energy transfer, thereby reducing the activation energy of the grafting reaction, and thus the sodium oleate is grafted onto the surface of the graphene.

[0028] As a preferred embodiment, the mass ratio of the graphene and the sodium oleate is 1: (1-3), and more preferably 1: (1-1.5). In the present application, the sodium oleate can be used in a slight excess, and the ungrafted sodium oleate can be removed by post-treatment.

[0029] As a preferred embodiment, a pretreatment is performed before the cold plasma treatment, comprising the following steps: grinding the mixture to achieve sufficient mixing of the two raw materials; in some more preferred embodiments, the particle size of the mixture is in the range of 800 mesh to 1000 mesh.

[0030] As a preferred embodiment, the cold plasma treatment comprises: first placing the mixture in a vacuum state, then adjusting to a working gas environment and electrifying to ionize the gas, so that the mixture is in a plasma environment and the reaction lasts for 5-10 minutes.

[0031] It is worth noting that the mixture needs to be placed in a vacuum state in priority, on the one hand to prevent the raw materials from being oxidized or contaminated by oxygen, water vapor and the like in the air, and on the other hand to lay the foundation for the subsequent plasma environment, reduce the energy loss when high-energy electrons collide with gas molecules, and improve the efficiency of plasma generation; in a common application scenario, the mixture is first placed in a plasma generator drum, and then the drum is pumped to vacuum to achieve the vacuum state.

[0032] As a more preferred embodiment, the working gas comprises at least one of nitrogen, helium, argon, neon, krypton, xenon or radon, and further preferably nitrogen; in some more preferred embodiments, the input amount of the working gas is 0.2 L / min to 0.4 L / min.

[0033] As a more preferred embodiment, the conditions of the power supply include: using direct current, voltage of 300V~400V, current of 40mA~60mA, power density of 40W / cm 2 ~60W / cm 2 .

[0034] In the present application, by controlling the above-mentioned cold plasma treatment conditions, the local overheating leading to material denaturation is avoided, the C-C bond of graphene is broken by glow discharge and the C=C in sodium oleate is broken into C-C bond, and then the graphene is grafted with sodium oleate.

[0035] As a preferred embodiment, after the cold plasma treatment, a post-treatment is further included, comprising the following steps: natural cooling, and then washing the product of the cold plasma treatment, and obtaining the collector after drying at room temperature. It is worth noting that the ungrafted sodium oleate molecules are washed away by the washing, so as to avoid affecting the subsequent experiments; in some more preferred embodiments, the medium of the washing includes deionized water.

[0036] The second aspect of the present application is to provide a collector prepared by the preparation method of the first aspect, which is used for collecting fine particle quartz ore.

[0037] The third aspect of the present application is to provide the application of the collector of the second aspect in a mineral flotation method.

[0038] As a preferred embodiment, the flotation recovery of fine particle quartz ore by the collector includes the following steps: first adjusting the pH of the ore pulp to 9~11 by a pH adjuster, and then adding the collector and a second collector, and performing the flotation operation after fully conditioning the pulp, scraping the flotation froth and obtaining the fine particle quartz ore.

[0039] As a preferred embodiment, the ore pulp can be derived from quartz ore, or other minerals containing quartz ore, including but not limited to non-metallic or metallic mineral resources with silicon dioxide as the main component.

[0040] As a preferred embodiment, the particle size of the minerals in the ore pulp ranges from-600 mesh; the solid content of the ore pulp is 1:15~30, unit: g / mL, and the solvent of the ore pulp is water, more preferably deionized water.

[0041] As a preferred embodiment, after adjusting the pH, the mineralization reaction is performed for 1min~3min, and then other reagents are added; in some optional embodiments, adjusting the pH value includes but is not limited to any one of 9, 9.2, 9.5, 9.8, 10, 10.2, 10.5, 10.8, 11 or a numerical interval composed of any two of them.

[0042] As a preferred embodiment, the pH regulator adopts sodium hydroxide.

[0043] As a preferred embodiment, the adding amount of the collector is 40 mg / L to 80 mg / L in terms of the mass of the ore pulp, including but not limited to any one of 40, 45, 50, 55, 60, 65, 70, 75, 80 (mg / L) or a numerical interval composed of any two of them.

[0044] As a preferred embodiment, the adding amount of the second collector is 20 mg / L to 80 mg / L in terms of the mass of the ore pulp, including but not limited to any one of 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80 (mg / L) or a numerical interval composed of any two of them.

[0045] As a preferred embodiment, the second collector includes a fatty acid compound or a hydroxamic acid compound; in some embodiments, the fatty acid compound includes one or more of oleic acid, sodium oleate, naphthenic acid, and the hydroxamic acid compound includes but is not limited to octyl hydroxamic acid, benzyl hydroxamic acid, salicyl hydroxamic acid, etc.

[0046] As a preferred embodiment, the collector is added first, and stirred for 2 min to 4 min; then the second collector is added, and stirred for 2 min to 4 min; and then the floating foam is scraped for 3 min to 5 min until the fine-grained quartz ore is obtained. As another preferred embodiment, the collector and the second collector are added to the ore pulp respectively, and after each addition, there is an independent addition duration of 1 min to 3 min, and a mineralization time after addition of 0.5 min to 2 min.

[0047] Example 1

[0048] The graphene and sodium oleate are mixed in a mass ratio of 1:1, and are fully mixed by a marquis mortar to obtain a mixed powder; the powder is poured into an ion generator roller, the inside of the generator is vacuumed, nitrogen gas is introduced as a protective gas, the gas flow is kept at 0.3 L / min, the direct current voltage is set to 350 V, the current is 50 mA, and the power density is 50 W / cm 2 The graphene and sodium oleate are grafted, after 8 min of reaction in the reactor, the generator is naturally cooled, the reagent after the reaction is taken out and washed with deionized water to wash off the molecules of sodium oleate that are not grafted to avoid affecting the subsequent experiment, and is naturally dried at room temperature to obtain the collector product of the present embodiment.

[0049] Example 2

[0050] The same as Example 1, except that the mass ratio of graphene to sodium oleate is 1:1.5.

[0051] Example 3

[0052] The same as Example 1, except that a direct current voltage of 380 V, a current of 60 mA, and a power density of 60 W / cm 2 .

[0053] Application Examples 1-6

[0054] Quartz pure minerals are selected, crushed and sieved to obtain quartz mineral particles with a particle size of-0.038 mm. The composition of the quartz pure minerals is detected by XRD, and the SiO2 content is more than 99%.

[0055] The quartz mineral particles are prepared into a slurry, and a 1wt.% NaOH solution is used as a pH adjuster to adjust the pH of the slurry to 9 and mineralize for 1 min. Then the modified reagent prepared in the example is added and reacted for 2 min, then sodium oleate is added and reacted for 2 min, and finally the flotation froth is scraped for 3 min. After drying, the quartz concentrate product recovered in this application example is obtained.

[0056] In this application example, the type and amount of the collector product prepared in the example are shown in Table 1 below, wherein the above-mentioned amount is the weight of the reagent added per liter of slurry, i.e. in mg / L.

[0057] The recovery rate and purity of the quartz concentrate product recovered in the application example are detected; wherein the tailings at the bottom of the flotation tank, i.e. the minerals that cannot effectively float with the collector, are determined as tailings, and the recovery rate refers to the weight of the concentrate product / (weight of the concentrate product+weight of the tailings) x 100%.

[0058] Table 1

[0059]

[0060] Comparative Example 1

[0061] In this comparative example, the same slurry as in the application example is selected; a 1wt.% NaOH solution is used as a pH adjuster to adjust the pH of the slurry to 9 and mineralize for 1 min. Then sodium oleate is added in an amount of 80 mg / L, stirred for 2 min, then aerated, and the froth is scraped for 3 min. The highest recovery rate is 49.97%.

[0062] Comparative Example 2

[0063] In the present comparative example, the same ore slurry as in the application example was selected; the pH of the ore slurry was adjusted to 9 by using 1 wt.% NaOH solution as pH regulator, and mineralized for 1 min. Then, 40 mg / L of sodium oleate was added, stirred for 2 min, and then aerated, with scraping for 3 min, and the highest recovery rate was 30.93%.

[0064] Although the present application has been illustrated and described with reference to specific embodiments, it should be recognized that the above examples are merely illustrative of the present application and are not intended to limit the scope of the present application. It will be apparent to those skilled in the art that various modifications, combinations, sub-combinations and alterations can occur to one skilled in the art without departing from the scope of the present application. Therefore, it is intended that the present application encompass all such modifications, combinations, sub-combinations and alterations as fall within the scope of the appended claims.

Claims

1. A process for the preparation of a collector for fine-grained quartz ores, characterized in that The method comprises the following steps: The mixture containing graphene and sodium oleate is subjected to cold plasma treatment to graft the graphene and the sodium oleate, thereby obtaining a collector.

2. The production method according to claim 1, characterized by, The mass ratio of the graphene and the sodium oleate is 1: (1-3).

3. The preparation method according to claim 1, characterized in that, The cold plasma treatment comprises the following steps: first, placing the mixture in a vacuum state, then adjusting to a working gas environment and electrifying to ionize the gas, so that the mixture is in a plasma environment and the reaction lasts for 5-10 minutes.

4. The production method according to claim 3, characterized by, The working gas comprises nitrogen, and the input amount of the working gas is 0.2-0.4 L / min. And / or, the energizing condition includes: using direct current, voltage is 300V~400V, current is 40mA~60mA, power density is 40W / cm 2 ~60W / cm 2 .

5. The collector prepared by the method for preparing a collector for fine-grained quartz ore according to any one of claims 1-4.

6. The collector according to claim 5 is applied to a mineral flotation method.

7. Use according to claim 6, characterized in that, The collector is used for the flotation recovery of fine-grained quartz ore, which comprises the following steps: First, the pH of the ore slurry is adjusted to 9-11 by a pH regulator, then the collector and a second collector are added, the ore slurry is fully stirred, and the flotation froth is scraped to obtain fine-grained quartz ore.

8. Use according to claim 7, characterized in that, The addition amount of the collector is 40-80 mg / L, and the addition amount of the second collector is 20-80 mg / L, based on the mass of the ore slurry.

9. Use according to claim 7, characterized in that, The second collector comprises a fatty acid compound or a hydroxamic acid compound.

10. Use according to claim 7, characterized in that, After adjusting the pH of the ore slurry, the collector is first added and stirred for 2-4 minutes, then the second collector is added and stirred for 2-4 minutes, and the flotation froth is scraped for 3-5 minutes until the fine-grained quartz ore is obtained.

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