Use of a copper ore depressant in the flotation of copper-containing ores

Abstract

The application belongs to the technical field of development of beneficiation reagent, and particularly relates to application of a copper ore depressant in flotation of copper-containing minerals, wherein the copper ore depressant includes but is not limited to homologues of 2,5-dithiodiurea, compounds with different carbon chain lengths or isomers at carbon chains. Compared with traditional copper ore depressants, the copper ore depressant has more prominent inhibition effect, and has the characteristics of less dosage, high efficiency and environmental protection. The application provides a new idea for developing efficient complex multi-metal copper-containing sulfide mineral resources and separating complex multi-metal mixed minerals, and provides a brand-new design direction for use of combined depressants.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of development and application of beneficiation reagents, in particular to application of a copper ore depressant in flotation of copper-containing minerals, which is suitable for flotation separation of copper-containing minerals. BACKGROUND

[0002] Flotation reagents are divided into collectors, depressants and frothers. In the early stage of the development of mineral processing, researchers focused on the development and utilization of collectors. Since the invention of O-isopropyl-N-ethyl thiocarbamate (Z-200) in the 1960s, the development of collectors has encountered a bottleneck. There are few reports on new flotation collectors with breakthrough progress in the 21st century. At the same time, scholars found that the selectivity of collectors is not high, which leads to the difficulty in separation of minerals. Therefore, some scholars turned their attention to the development of depressants.

[0003] In recent years, the large demand of human beings for resources has led to rapid consumption of ores with good composition and easy separation. More and more poor, fine and miscellaneous ores have attracted people's attention. In addition, tailings from selected mines are recycled and subjected to secondary flotation, which undoubtedly increases the difficulty of mineral flotation separation. The principle of depressant is to control the hydrophobicity of mineral surface to make the mineral hydrophilic, so as to better selectively separate useful ores and gangue minerals. The inhibition process mainly includes two steps. The first step is that the depressant fully contacts with the target mineral and interacts with each other. The second step is that the depressant molecules that have interacted with the target mineral make the target mineral hydrophilic by using the hydrophilic effect of the polar group, so as to achieve the inhibition effect. The addition of depressant can not only improve the separation index of mineral flotation, but also reduce the use amount of adjusting agent or even collector when the process flow is appropriate, thereby reducing the beneficiation cost. Therefore, the depressant is an indispensable flotation reagent for better separation of minerals, and the development of new and efficient depressants has high research value.

[0004] The use amount of copper metal ranks the top three among non-ferrous metals, and it is an indispensable non-ferrous metal in people's life. In the past flotation process, sodium sulfide is usually used as a depressant for chalcopyrite. However, for some complex and difficult-to-select mine minerals, the addition amount of sodium sulfide is as high as 70-80 kg / t, which causes environmental pollution due to large addition amount. Therefore, a better depressant is needed to replace sodium sulfide. SUMMARY

[0005] The purpose of the present application is to provide application of a copper ore depressant in flotation of copper-containing minerals. 2,5-dithiodiurea is used as a depressant for copper-containing minerals, which has low requirement for pH in the flotation process, good stability, small amount of use, and can reduce environmental pollution in the beneficiation process.

[0006] The application realizes the above-mentioned purpose through the following technical scheme: application of a copper ore depressant in copper ore flotation, wherein the copper ore depressant includes but is not limited to homologues of 2,5-dithiodiurea, compounds with different carbon chain lengths or isomers at the carbon chain,

[0007] The preparation method of the copper ore depressant includes the following steps:

[0008] ①Preparation of a weak alkali solution: sodium hydroxide and deionized water are prepared according to the mass percentage of 0.3%-0.7% of sodium hydroxide and 99.3%-99.7% of deionized water;

[0009] ②Preparation of the copper depressant: 2,5-dithiodiurea is dissolved in the above-mentioned weak alkali solution containing sodium hydroxide, and stirring is performed for 5 minutes to make the 2,5-dithiodiurea completely dissolved, and the composition according to the molar mass fraction is 15%-25% of sodium hydroxide and 75%-85% of 2,5-dithiodiurea.

[0010] The application of the copper ore depressant in copper ore flotation, wherein the mineral raw material is chalcopyrite, the mineral contains 22.13% of copper, 21.11% of iron and a small amount of 0.21% of zinc, the sample is mainly chalcopyrite, and copper blue is occasionally seen, wherein the mineral particle size of the chalcopyrite is 0.02-0.4 mm, and the particle size of the copper blue is below 0.03 mm; the iron mineral is mainly limonite, and magnetite is occasionally seen, wherein the particle size of the limonite is half between 0.005-0.05 mm, and the particle size of the magnetite is between 0.02-0.25 mm; the content of the gangue mineral is relatively high, and the gangue mineral is quartz and feldspar, followed by mica, chlorite and hornblende, and a small amount of pyroxene, garnet, calcite, dolomite, sphene, kaolinite and rutile; the embedded particle size of the copper mineral is between-0.30+0.037, wherein when the particle size is +0.037, the cumulative distribution rate of the copper mineral is 96.46%,

[0011] The copper mineral is floated by using the copper ore depressant, and the flotation process includes:

[0012] (1) the grinding fineness is-200 mesh content of 60-70%, and the pulp is adjusted for 2-5 minutes;

[0013] (2) the copper ore depressant is added at 10-2500 g / t, and the pulp is adjusted for 2-5 minutes;

[0014] (3) the collector ethyl xanthate is added at 1-100 g / t, and the pulp is adjusted for 2-5 minutes;

[0015] (4) the amount of the frother methyl isobutyl carbinol is 15-25 g / t, and the pulp is adjusted for 2-5 minutes after the frother is added;

[0016] (5) the roughing time is 3-5 minutes,

[0017] The grade of copper in the tailings is 15%-20%, and the grade of copper in the concentrate is 1.0-2.0%.

[0018] Chemical principle:

[0019] According to the coordination chemical principle, there are multiple pairs of electron pairs on the 3d orbital of the copper ion on the surface of the mineral, which can form a stable feedback pi bond with the reagent having an empty pi orbital. Figure 3 As shown in the LUMO orbital diagram of 2,5-dithiobiuret, it can be found that there are empty pi orbitals on the double bond sulfur of 2,5-dithiobiuret, which meets the first step of the effect of the inhibitor, that is, 2,5-dithiobiuret can stably interact with copper. As shown in Figure 3 , it can be known from Figure 3 that the polarity of 2,5-dithiobiuret is strong, that is, after the sulfur atom interacts with the copper mineral, the polar group of the reagent undergoes hydrophilic interaction to produce an inhibitory effect.

[0020] The present application has the following beneficial effects:

[0021] Under the same environmental and same dosing conditions, the inhibitory effect of the present application on copper minerals is higher than that of the traditional copper mineral inhibitor. The double bond sulfur in the inhibitor is used as an active site for interaction with copper minerals, has a strong empty pi orbital to receive the pi electron pair of the copper ion, and uses the polar group of the inhibitor to achieve hydrophilic purposes, so that the inhibitor interacts with the copper mineral more stably, more environmentally friendly and efficient, and does not produce irritating odor in the application process; it can exist stably under acid and alkali conditions. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 XRD test data of chalcopyrite raw material for implementation case

[0023] Figure 2 It is the structural formula of 2,5-dithiobiuret.

[0024] Figure 3 It is the empty pi orbital of the sulfur atom in 2,5-dithiobiuret, which is used to receive the pi electron pair of the copper ion to form a feedback pi bond.

[0025] Figure 4 It is the electrostatic potential of 2,5-dithiobiuret, indicating that the polarity of 2,5-dithiobiuret is strong, and according to the principle of similar dissolves similar, it is proved that 2,5-dithiobiuret is a polar molecule that is easy to interact with water. DETAILED DESCRIPTION

[0026] The technical solutions of the present application are further described in detail through specific embodiments.

[0027] As Figure 2The main component of the copper ore depressant is 2,5-dithiobiuret, including but not limited to homologues, compounds with different carbon chain lengths or isomers at the carbon chain of 2,5-dithiobiuret.

[0028] The preparation method of the copper ore depressant comprises the following steps:

[0029] ①Preparation of weak alkaline solution: according to the mass percentage of sodium hydroxide 0.3%-0.7%, and deionized water 99.3%-99.7% for preparation;

[0030] ②Preparation of the copper ore depressant: dissolving 2,5-dithiobiuret in the above-mentioned weak alkaline solution containing sodium hydroxide,

[0031] stirring for 5 minutes to completely dissolve 2,5-dithiobiuret. According to the molar mass fraction, the composition is: sodium hydroxide 15%-25%,

[0032] 2,5-dithiobiuret 75%-85%.

[0033] Example 1

[0034] This embodiment is an example of the application of the copper ore depressant of the present application in copper ore flotation, comprising the following steps:

[0035] Mineral raw materials:

[0036] The copper ore used in the test is taken from a certain mine in Guangxi. The ore needs to be artificially preselected, and the block sample with uniform block and complete crystallinity is selected out, knocked into smaller particles, and then artificially ground and dry screened to obtain a flotation sample. Figure 1 The XRD data of this sample shows that the selected pure mineral is chalcopyrite. The chemical composition detection uses ThermoNiton xL3 handheld element analyzer, and the measurement shows that the sample contains copper 22.35%, iron 20.51%, sulfur 8.13%, and a small amount of zinc 0.11%.

[0037] In order to test the inhibitory effect of the reagent of the present application on copper ore, the copper ore depressant of the present application is used for flotation test of the above-mentioned copper ore sample under the condition of no collector, and the flotation process comprises:

[0038] (1) 2g of the above-mentioned copper ore sample with particle size of 120-200 is weighed for pure mineral flotation test;

[0039] (2) Put it into an ultrasonic cleaner to clean the surface for 3 minutes;

[0040] (3) Pour into the flotation tank, add 30ml of deionized water, and adjust the pulp for 4 minutes;

[0041] (4) adding the copper ore depressant 4 g / t for 2 minutes of conditioning;

[0042] (5) the amount of foaming agent methyl isobutyl carbinol is 20 g / t, and the foaming agent is added for 4 minutes of conditioning after the addition of the foaming agent

[0043] (6) scraping bubbles for 3 minutes.

[0044] The data obtained in the pure mineral experiment under ideal neutral conditions without the use of a collector show that when the amount of the copper ore depressant prepared in the present application is only 4 g / t, the recovery rate of copper can be reduced to 6.5%. In comparison, when 2,5-dithiobiuret is not added, the recovery rate of copper is 77%. In the pure mineral experiment under the same conditions of a certain reagent being used in industrial production, when the amount of the reagent is 15 g / t, the recovery rate of copper ore is still as high as 72.5%.

[0045] Example 2

[0046] This example is another example of the application of the copper ore depressant described in the present application in the flotation of copper-containing minerals, and includes the following steps:

[0047] Mineral raw material: the raw material is the same as in Example 1, which is a copper ore from a certain mine in Guangxi that has been artificially sorted.

[0048] In view of the influence of the use of a collector on the inhibitory effect of the copper ore depressant prepared in the present application on copper minerals, a flotation test was conducted on copper minerals using the reagent described in the present application under the condition of using ethyl xanthate as a collector, and the flotation process includes:

[0049] (1) 2 g of the above-mentioned copper mineral particles with a particle size of 120-200 mesh were weighed for a pure mineral flotation test;

[0050] (2) the surface was cleaned in an ultrasonic cleaner for 3 minutes;

[0051] (3) the particles were poured into a flotation tank, 30 ml of deionized water was added, and the particles were conditioned for 4 minutes;

[0052] (4) the copper ore depressant 11 g / t was added, and the particles were conditioned for 2 minutes;

[0053] (5) the collector ethyl xanthate 1 g / t was added, and the particles were conditioned for 2 minutes;

[0054] (6) the amount of foaming agent methyl isobutyl carbinol is 20 g / t, and the foaming agent is added for 4 minutes of conditioning after the addition of the foaming agent

[0055] (7) scraping bubbles for 3 minutes.

[0056] The concentration of the inhibitor needs to be appropriately increased in the presence of the collector, and when the dosage of 2,5-dithiobiuret is 11 g / t, the recovery rate of copper is inhibited to 16.0%. When the dosage of a certain industrial copper ore inhibitor is 50 g / t, the recovery rate of copper ore is inhibited to 16.5%, and it can be found that the industrial dosage is higher than the dosage of the agent used in the present application.

[0057] Example 3

[0058] This example is another example of the application of the copper ore inhibitor described in the present application in the flotation of copper-containing minerals, which includes the following steps:

[0059] Mineral raw material: The raw material is the same as in Example 1, which is the artificially sorted copper ore of a certain mine in Guangxi.

[0060] Increase the dosage of the collector to test the effect of the copper ore inhibitor prepared in the present application on the inhibition of copper ore. Under the condition of using ethyl xanthate as the collector, the copper ore is subjected to flotation test using the agent described in the present application, and the flotation process includes:

[0061] (1) 2 g of the above-mentioned copper ore particles with a particle size of 120-200 mesh are weighed for pure mineral flotation test;

[0062] (2) The surface is cleaned in an ultrasonic cleaner for 3 minutes;

[0063] (3) Pour into a flotation tank, add 30 ml of deionized water, and adjust the pulp for 4 minutes;

[0064] (4) Add the copper ore inhibitor 1000 g / t, and adjust the pulp for 2 minutes;

[0065] (5) Add the collector ethyl xanthate 50 g / t, and adjust the pulp for 2 minutes;

[0066] (6) The dosage of the frother methyl isobutyl carbinol is 20 g / t, and the pulp is adjusted for 4 minutes after adding the frother

[0067] (7) Scrape the froth for 3 minutes.

[0068] As the dosage of the collector increases, the dosage of the inhibitor continues to increase. When the dosage of 2,5-dithiobiuret is 1000 g / t, the recovery rate of copper is inhibited to 18.5%.

[0069] Example 4

[0070] This example is another example of the application of the copper ore inhibitor described in the present application in the flotation of copper-containing minerals, which includes the following steps:

[0071] Mineral raw material: The raw material is the same as in Example 1, which is the artificially sorted copper ore of a certain mine in Guangxi.

[0072] Due to the high concentration of industrial dosage, the dosage of collector is continuously increased to test the effect of the depressant. Under the condition of high concentration ethyl xanthate as the collector, the flotation test of copper minerals is carried out using the reagent of the application, and the flotation process includes:

[0073] (1) 2g of the above-mentioned copper mineral particles with a particle size of 120-200 were weighed for pure mineral flotation test;

[0074] (2) The surface was cleaned in an ultrasonic cleaner for 3 minutes;

[0075] (3) Pour into the flotation tank, add 30ml of deionized water, and adjust the pulp for 4 minutes;

[0076] (4) Add the copper ore depressant 2500g / t, and adjust the pulp for 2 minutes;

[0077] (5) Add the collector ethyl xanthate 100g / t, and adjust the pulp for 2 minutes;

[0078] (6) The dosage of the frother methyl isobutyl carbinol is 20g / t, and the pulp is adjusted for 4 minutes after adding the frother

[0079] (7) Scrape the froth for 3 minutes.

[0080] When the dosage of the copper ore depressant prepared by the application is 2500g / t, the recovery rate of copper is inhibited to 17.0%.

[0081] Example 5

[0082] This example is another example of the application of the copper ore depressant of the application in the flotation of copper-containing minerals, which includes the following steps:

[0083] Mineral raw material: The raw material is the same as in Example 1, which is the artificially sorted copper ore of a copper mine in Guangxi.

[0084] The effect of pH on the copper ore depressant prepared by the application was investigated. The copper ore depressant prepared by the application was used to carry out flotation test of copper minerals, and the flotation process includes:

[0085] (1) 2g of the above-mentioned copper mineral particles with a particle size of 120-200 were weighed for pure mineral flotation test;

[0086] (2) The surface was cleaned in an ultrasonic cleaner for 3 minutes;

[0087] (3) Pour into the flotation tank, respectively add 30ml of solution with pH value of 3, 5, 7, 9, 11, 13 prepared by NaOH, and adjust the pulp for 4 minutes;

[0088] (4) Add the copper ore depressant 10g / t, and adjust the pulp for 2 minutes;

[0089] (5) Add collector ethyl xanthate 1 g / t, and adjust pulp for 2 minutes;

[0090] (6) The amount of foaming agent methyl isobutyl carbinol is 20 g / t, and the foaming agent is added and adjusted for 4 minutes after the addition of the foaming agent;

[0091] (7) Scrape foam for 3 minutes.

[0092] Table 1 Recovery rate of copper ore after using the copper ore depressor prepared in the application under different pH values

[0093]

[0094] Table 1 is the recovery rate of copper ore after using the copper ore depressor prepared in the application under different pH values, and it can be found that the copper ore depressor prepared in the application has good performance in pH stability, has good inhibition effect under neutral conditions, and the acid-base conditions have little effect on the inhibition effect of the copper ore depressor prepared in the application on the copper ore, proving that it has good stability. The copper ore depressor prepared in the application has excellent inhibition effect at pH 3-13, and the recovery rate of copper is less than 10%. Currently, the pH of industrial drugs usually needs to be at 7-13 to show good inhibition effect.

[0095] Example 6

[0096] This example is another example of the application of the copper ore depressor described in the application in copper mineral flotation, which comprises the following steps:

[0097] Mineral raw material: The chalcopyrite used in the test is taken from a mine in Yunnan, and the sample after grinding is analyzed and determined by Thermo Niton xL3 handheld element analyzer. The analysis shows that the mineral contains copper 22.13%, iron 21.11%, and a small amount of zinc 0.21%. It is identified that the sample is mainly chalcopyrite, and occasionally copper blue, among which the mineral particle size of chalcopyrite is 0.02-0.4 mm, and the particle size of copper blue is basically below 0.03 mm; the iron mineral is mainly limonite, and occasionally magnetite, among which the particle size of limonite is half between 0.005-0.05 mm, and the particle size of magnetite is between 0.02-0.25 mm; the content of gangue minerals is high, and the secondary is mica, chlorite and hornblende, and contains a small amount of pyroxene, garnet, calcite, dolomite, sphene, kaolinite and rutile. The embedded particle size of the copper mineral used in the test is mainly between-0.30+0.037, among which when the particle size is +0.037, the cumulative distribution rate of copper mineral is 96.46%.

[0098] The copper mineral is floated by using the copper ore depressor, and the flotation process comprises:

[0099] (1) the grinding fineness is -200 mesh content 65%, and the pulp is stirred for 3 minutes;

[0100] (2) the dosage of foaming agent methyl isobutyl carbinol is 20 g / t, and the pulp is stirred for 4 minutes after adding the foaming agent;

[0101] (3) the copper ore inhibitor is added at 800 g / t, and the pulp is stirred for 2 minutes;

[0102] (4) the collector ethyl xanthate is added at 40 g / t, and the pulp is stirred for 2 minutes;

[0103] (5) the roughing time is 3 minutes,

[0104] The grade of copper in the tailings is 15%-20%, and the grade of copper in the concentrate is 1.0-2.0%.

[0105] The test shows that when the dosage of the copper ore inhibitor prepared by the application is 800 g / t, the grade of copper in the tailings is 18.84%, and the grade of copper in the concentrate is 1.62%; when the dosage of the above-mentioned industrial copper ore inhibitor is 2500 g / t, the grade of copper in the tailings is 18.86%, and the grade of copper in the concentrate is 1.71%. The inhibition effects are close, but the dosage of the reagent used by the application is only 1 / 3 of the dosage of the industrial reagent.

Claims

1. The application of a 2,5-dithiodiurea homologue, characterized in that, 2,5-Dithiodiurea homologues were used as copper ore depressants to inhibit chalcopyrite in the flotation of copper-bearing minerals. The homologues of the 2,5-dithiodiurea are compounds having the structural formula of Formula 1: Formula 1, In the formula, H is a hydrogen atom, N is a nitrogen atom, S is a sulfur atom, and C is a carbon atom.

2. The application of the 2,5-dithiourea homologue according to claim 1, characterized in that, The 2,5-dithiodiurene homologue is used as a copper ore inhibitor and is prepared according to the following steps: ①Preparation of a weakly alkaline solution: Prepare a solution by mixing sodium hydroxide and deionized water according to the mass percentages of 0.3%-0.7% sodium hydroxide and 99.3%-99.7% deionized water. ② Preparation of copper ore inhibitor: Dissolve 2,5-dithiodiurea in the above weakly alkaline solution containing sodium hydroxide, stir for 5 minutes to completely dissolve 2,5-dithiodiurea, and its composition according to molar mass percentage is: sodium hydroxide 15%-25%, 2,5-dithiodiurea 75%-85%, to prepare the copper ore inhibitor.

3. The application of the 2,5-dithiourea homologue according to claim 1, characterized in that, The copper minerals are floated using the aforementioned copper ore depressant. The flotation process includes: S1. Grinding fineness is -200 mesh, content is 60-70%, and slurry preparation time is 2-5 minutes; S2. Add 10-2500 g / t of the copper ore inhibitor and adjust the slurry for 2-5 minutes; S3. Add 1-100 g / t of the collector ethyl xanthate and adjust the slurry for 2-5 minutes; S4. The amount of foaming agent methyl isobutyl methanol is 15-25 g / t. After adding the foaming agent, adjust the slurry for 2-5 minutes. S5. The coarse selection time is 3-5 minutes. The copper grade in the tailings is 15%-20%, and the copper grade in the concentrate is 1.0-2.0%.

4. The application of the 2,5-dithiourea homologue according to claim 1, characterized in that, The copper minerals are floated using the aforementioned copper ore depressant. The flotation process includes: a. Grinding fineness is -200 mesh, content is 65%, and slurry is prepared for 3 minutes; b. Add 800 g / t of the copper ore inhibitor and adjust the slurry for 2 minutes; c. Add 40g / t of the collector ethyl xanthate and mix for 2 minutes; d. The amount of foaming agent methyl isobutyl methanol is 15-25 g / t. After adding the foaming agent, adjust the slurry for 2-5 minutes. e. The initial screening time is 3 minutes. The copper grade in the tailings was 18.84%, and the copper grade in the concentrate was 1.62%.

5. The application of the 2,5-dithiourea homologue according to claim 1, characterized in that, The copper minerals are floated using the aforementioned copper ore depressant. The flotation process includes: A. Weigh 2g of the above copper mineral particles of 120-200 mesh and conduct a pure mineral flotation test; B. Place the surface in an ultrasonic cleaner for 3-5 minutes; C. Pour into the flotation cell, add 25-30 ml of NaOH solution prepared to a pH of 3-13, and adjust the slurry for 3-5 minutes; D. Add 10-20 g / t of the copper ore inhibitor and adjust the slurry for 2-3 minutes; E. Add 1-2 g / t of the collector ethyl xanthate and mix for 2 minutes; F. The amount of foaming agent methyl isobutyl methanol is 15-25 g / t. After adding the foaming agent, adjust the slurry for 2-5 minutes. G. Scrape and soak for 3-5 minutes.

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