Flotation separation method for molybdenite and bismuthite

Abstract

The invention provides a flotation separation method for molybdenite and bismuthite. The flotation separation method comprises the following steps that an ore sample containing the molybdenite and the bismuthite is sorted, crushed and ground to serve as a flotation sample; minerals and water are mixed to form ore pulp, and the pH value of the ore pulp is adjusted to a certain value; adding a certain amount of oxidizing agent into the ore pulp and stirring; adding a certain amount of inhibitor into the ore pulp, and stirring; a certain amount of collecting agent is added into the ore pulp, and stirring treatment is conducted; adding a certain amount of foaming agent into the ore pulp, and stirring; and S5, carrying out foam flotation on the ore pulp obtained in the step S5, respectively filtering, drying and testing a foam product and a tank bottom product after flotation, and calculating the recovery rate. The efficient and environment-friendly collecting agent and selective inhibitor are provided, efficient separation of molybdenite and bismuthite can be achieved, the utilization efficiency of mineral resources is improved, the influence on the environment is further reduced, and technical support is provided for sustainable development of mines.

Description

Technical Field

[0001] The invention relates to the technical field of sulfide ore flotation reagents, in particular to a flotation separation method for molybdenite and bismuthinite. Background Art

[0002] Molybdenum metal has an irreplaceable position in modern industry due to its excellent strength and high melting point. It is widely used in a variety of fields such as aerospace, agriculture, medical devices and electrode materials. Molybdenite (MoS2) and bismuthinite (Bi2S3), as the main mineral sources of molybdenum and bismuth, often exist in a symbiotic form in nature. Flotation technology, as an effective means of separating these two minerals, has always been the focus of research on its efficiency and selectivity.

[0003] Although studies have attempted to use non-polar oils, xanthates, etc. as collectors for combined flotation, it is still challenging to effectively separate molybdenite and bismuthinite due to the similarities in their flotation properties. In order to improve the flotation separation effect and enhance the difference in surface hydrophobicity between molybdenite and bismuthinite, researchers have developed a variety of inhibitors. Sodium sulfide, as an inorganic inhibitor widely used in industry, can reduce the floatability of bismuthinite, but its use has problems such as large dosage, production of harmful gas sulfur dioxide, and possible reduction in molybdenite recovery. Oxidants such as hydrogen peroxide or calcium hypochlorite have also been tried as inhibitors, which can reduce the floatability of bismuthinite, but the strong oxidizing effect of hydrogen peroxide and the potential negative impact of calcium hypochlorite on the environment and equipment, as well as Ca 2+ The adverse effect on molybdenite flotation limits their application. Summary of the invention

[0004] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a method for flotation separation of molybdenite and bismuthinite to solve the problems raised in the above-mentioned background technology. The present invention provides an efficient and environmentally friendly collector and selective inhibitor, which can achieve efficient separation of molybdenite and bismuthinite, improve the utilization efficiency of mineral resources, reduce the impact on the environment, and provide technical support for the sustainable development of mines.

[0005] In order to achieve the above object, the present invention is implemented by the following technical scheme: a flotation separation method of molybdenite and bismuthinite, comprising the following steps:

[0006] S1. Sorting and crushing the ore samples containing molybdenite and bismuthinite, and grinding them to a particle size range of 0.038-0.074 mm as flotation samples;

[0007] S2, mixing the mineral with water to form a slurry, and adjusting the slurry to a certain pH value;

[0008] S3, adding a certain amount of oxidant to the slurry and stirring;

[0009] S4. Add a certain amount of inhibitor to the slurry and stir it;

[0010] S5. Add a certain amount of collector into the slurry and stir it;

[0011] S6. Add a certain amount of foaming agent into the slurry and stir it;

[0012] S7, subjecting the ore pulp obtained in step S6 to froth flotation, filtering, drying, and testing the froth product and the bottom product after flotation, respectively, and calculating the recovery rate.

[0013] Furthermore, a pH adjuster is used in S2 to adjust the pH value of the slurry and control it between 4 and 12; the pH adjuster is hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid or lime, sodium carbonate, sodium hydroxide.

[0014] Furthermore, the oxidant in S3 is any one or a combination of ammonium persulfate, potassium permanganate, calcium hypochlorite and hydrogen peroxide, the certain amount of oxidant is: 0-100 mg / L, and the stirring time is 1 min to 30 min.

[0015] Furthermore, the inhibitor in S4 is any one or a combination of citric acid, L-cysteine, AMT and thioglycolic acid, and the molecular structure of AMT is:

[0016]

[0017] Furthermore, the amount of the inhibitor added to S4 is 3×10 -6 mol / L~2×10 -2 mol / L, stirring and slurrying time is 1 to 10 minutes.

[0018] Furthermore, the ratio of the oxidant to the inhibitor in S3 and S4 is 20:1 to 1:20; the dosage of both is 6×10 -6 ~8×10 -2 mol / L.

[0019] Furthermore, the collector in S5 is any one or a combination of O-isopropyl-N-ethylthiocarbamate, non-polar oil and isobutyl xanthate, the dosage of the collector is 1-200 mg / L, and the stirring and slurrying time is 1-6 min.

[0020] Furthermore, the collector components are in the following proportions: 20 to 75 parts of O-isopropyl-N-ethylthiocarbamic acid, 5 to 20 parts of non-polar oil, and 20 to 60 parts of isobutyl xanthate.

[0021] Furthermore, the foaming agent in S6 is any one of eucalyptus oil, methyl amyl alcohol, and alkyl polypropylene glycol ether, or a combination of several of them; and the dosage of the foaming agent is: 1-100 mg / L.

[0022] Beneficial effects of the present invention:

[0023] 1. The flotation separation method of molybdenite and bismuthinite adopts organic inhibitors. The organic inhibitors adopted are all naturally occurring small molecule organic acids with good biodegradability and low toxicity, which are in line with the current trend of environmental protection and sustainable development.

[0024] 2. The flotation separation method of molybdenite and bismuthinite uses an oxidant + inhibitor. The oxidant helps to oxidize the surface of the mineral. The organic inhibitor molecule contains multiple carboxyl groups, amino groups, thiol groups and hydroxyl groups. These functional groups have excellent chelating ability for metal ions, which helps the organic inhibitor to form a stable chemical bond with the bismuth ions exposed on the surface of bismuthinite, effectively reducing the floatability of bismuthinite. The inhibitor has good selectivity for bismuthinite, thus providing a new technical approach for the flotation separation of molybdenite and bismuthinite.

[0025] 3. The collector used in the present invention has good synergistic effect, and the frother has good selectivity. The method can be applied to the flotation separation process of molybdenum-bismuth mixed concentrate, can effectively improve the separation efficiency of bismuthinite and molybdenite, and realize the efficient flotation separation of the two minerals, and has significant industrial application potential. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The flotation separation reagent and process flow chart of molybdenite and bismuthinite of the present invention;

[0027] Figure 2 This is a curve diagram showing the effect of the amount of isobutyl xanthate on the flotation of molybdenite and bismuthinite in Example 1 of the present invention;

[0028] Figure 3 This is a curve diagram showing the effect of Example 2Z-200 of the present invention on the flotation of molybdenite and bismuthinite;

[0029] Figure 4 This is a curve diagram showing the effect of citric acid dosage on the flotation of molybdenite and bismuth sulphate in Example 3 of the present invention;

[0030] Figure 5 This is a curve diagram showing the effect of the amount of L-cysteine ​​on the flotation of molybdenite and bismuth sulphate in Example 4 of the present invention;

[0031] Figure 6 This is a curve diagram showing the effect of AMT dosage on the flotation of molybdenite and bismuth sulphate in Example 5 of the present invention;

[0032] Figure 7This is a curve diagram showing the effect of the amount of thioglycolic acid on the flotation of molybdenite and bismuth sulphate in Example 6 of the present invention;

[0033] Figure 8 This is a curve diagram showing the effect of the ratio of oxidant to inhibitor on the flotation separation of mixed ore in Example 7 of the present invention;

[0034] Fig. 9 This is a curve diagram showing the effect of the dosage of oxidant and inhibitor on the flotation separation of mixed ore in Example 8 of the present invention. DETAILED DESCRIPTION

[0035] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0036] See also Figures 1 to 9 , the present invention provides the following technical solutions:

[0037] Example 1

[0038] Take 2g of bismuthinite and molybdenite with a particle size of 38-74μm and 35mL of ultrapure water and add them to a 40mL hanging tank flotation machine, stir and slurry at a speed of 1758r / min to fully disperse the slurry; do not add inhibitors, and adjust the pH value of the bismuthinite and molybdenite slurry to 8. Figure 1 The process and reagent system described above add reagents, and the collector is isobutyl xanthate; the concentrations of the collector are 5, 10, 15, and 20 mg / L respectively. After stirring, aeration flotation is performed to obtain a foam product and a tank bottom product. The foam product and the tank bottom product are filtered, dried, and weighed respectively, and the recovery rate is calculated. The results are as follows Figure 2 shown.

[0039] like Figure 2 It can be seen that the collector has a good collection ability for molybdenite and bismuthinite when the dosage is 15 mg / L. When the dosage is increased, the recovery rate remains basically stable.

[0040] Example 2

[0041] Take 2g of bismuthinite and molybdenite with a particle size of 38-74μm and 35mL of ultrapure water and add them to a 40mL hanging tank flotation machine, stir and slurry at a speed of 1758r / min to fully disperse the slurry; do not add inhibitors, and adjust the pH value of the bismuthinite and molybdenite slurry to 8. Figure 1 The process and reagent system described above add reagents, and the collector is isobutyl xanthate; the concentrations of the collector are 0, 10, 20, 30, and 60 mg / L. After stirring, aeration flotation is performed to obtain a foam product and a tank bottom product. The foam product and the tank bottom product are filtered, dried, and weighed, and the recovery rate is calculated. The results are as follows Figure 2 shown.

[0042] like Figure 2 It can be seen that the collector has a good collection capacity for molybdenite and bismuthinite when the dosage is 20 mg / L, and the recovery rate of molybdenite reaches 94.32% and that of bismuthinite 86%. When the dosage is further increased, the recovery rate remains basically stable.

[0043] Example 3

[0044] Take 2g of bismuthinite and molybdenite and 35mL of ultrapure water respectively and add them into 40mL of hanging tank flotation machine, stir and slurry at a speed of 1758r / min to make the slurry fully dispersed; after adding the inhibitor citric acid, the pH of bismuthinite and molybdenite is adjusted to 8 respectively, and the order of adding the reagents is as follows: Figure 1 As shown, the inhibitor citric acid was added, and the inhibitor concentrations were 0 and 1×10 -4 , 2×10 -4 , 4×10 -4 , 6×10 -4 , 1×10 -3 mol / L, O-isopropyl-N-ethylthiocarbamic acid (20 mg / L), methyl amyl alcohol (10 mg / L) as the foaming agent, and stirred for 3 min, 3 min, and 3 min respectively after adding the reagents. After stirring, aeration flotation was performed to obtain the foam product and the bottom product. The foam product and the bottom product were filtered, dried, and weighed respectively, and the recovery rate was calculated. The results are as follows Figure 4 shown.

[0045] like Figure 4 It can be seen that under the condition of slurry pH value of 8, the inhibitor dosage test was continued. When the inhibitor dosage reached 4×10 -4 mol / L, the flotation recovery of bismuthinite tended to stabilize and dropped below 20%, while the recovery of molybdenite remained at around 90%, indicating that the inhibitor had a weak inhibitory effect on molybdenite.

[0046] Example 4

[0047] Take 2g of bismuthinite and molybdenite and 35mL of ultrapure water respectively and add them into 40mL of hanging tank flotation machine, stir and slurry at a speed of 1758r / min to make the slurry fully dispersed; after adding the inhibitor L-cysteine, adjust the pH of bismuthinite and molybdenite to 8 respectively, and the order of adding the reagents is as follows: Figure 1 As shown, the inhibitor citric acid was added, and the inhibitor concentrations were 0 and 1×10 -4 , 2×10 -4 , 4×10 -4 , 6×10 -4 , 1×10 -3mol / L, O-isopropyl-N-ethylthiocarbamic acid (20 mg / L), methyl amyl alcohol (10 mg / L) as the foaming agent, and stirred for 3 min, 3 min, and 3 min respectively after adding the reagents. After stirring, aeration flotation was performed to obtain the foam product and the bottom product. The foam product and the bottom product were filtered, dried, and weighed respectively, and the recovery rate was calculated. The results are as follows Figure 4 shown.

[0048] like Figure 5 It can be seen that under the condition of slurry pH value of 8, the dosage of L-cysteine ​​was continued to be tested. When the dosage of L-cysteine ​​reached 6×10 -4 mol / L, the flotation recovery of bismuthinite tended to stabilize and dropped below 20%, while the recovery of molybdenite remained at around 90%, indicating that the inhibitory effect of L-cysteine ​​on molybdenite was weak.

[0049] Example 5

[0050] Take 2g of bismuthinite and molybdenite and 35mL of ultrapure water respectively and add them into 40mL of hanging tank flotation machine, stir and slurry at a speed of 1758r / min to make the slurry fully dispersed; after adding the inhibitor AMT, the pH of bismuthinite and molybdenite is adjusted to 8 respectively, and the order of adding the reagents is as follows: Figure 1 As shown, the inhibitor citric acid was added, and the inhibitor concentrations were 0 and 1×10 -4 , 2×10 -4 , 4×10 -4 , 6×10 -4 , 1×10 -3 mol / L, O-isopropyl-N-ethylthiocarbamic acid (20 mg / L), methyl amyl alcohol (10 mg / L) as the foaming agent, and stirred for 3 min, 3 min, and 3 min respectively after adding the reagents. After stirring, aeration flotation was performed to obtain the foam product and the bottom product. The foam product and the bottom product were filtered, dried, and weighed respectively, and the recovery rate was calculated. The results are as follows Figure 6 shown.

[0051] like Figure 6 It can be seen that with the increase of AMT dosage, the recovery rate of bismuthinite gradually decreases. -4 mol / L, the recovery rate dropped to 21%; when the amount of AMT was increased to 1×10 -3 mol / L, the recovery rate of bismuthinite remained stable at 20%, indicating that further increasing the dosage of AMT had little effect on the inhibition of bismuthinite; the recovery rate of molybdenite remained basically unchanged with the increase of the dosage of AMT, and remained above 92%, indicating that AMT would not inhibit molybdenite.

[0052] Example 6

[0053] Take 2g of bismuthinite and molybdenite and 35mL of ultrapure water respectively and add them into 40mL of hanging tank flotation machine, stir and slurry at a speed of 1758r / min to make the slurry fully dispersed; after adding the inhibitor thioglycolic acid, the pH of bismuthinite and molybdenite is adjusted to 8 respectively, and the order of adding the reagents is as follows: Figure 1 As shown, the inhibitor citric acid was added, and the inhibitor concentrations were 0 and 1×10 -4 , 2×10 -4 , 4×10 -4 , 6×10 -4 , 1×10 -3 mol / L, O-isopropyl-N-ethylthiocarbamic acid (20 mg / L), methyl amyl alcohol (10 mg / L) as the foaming agent, and stirred for 3 min, 3 min, and 3 min respectively after adding the reagents. After stirring, aeration flotation was performed to obtain the foam product and the bottom product. The foam product and the bottom product were filtered, dried, and weighed respectively, and the recovery rate was calculated. The results are as follows Figure 7 shown.

[0054] like Figure 7 It can be seen that under the condition of pulp pH value of 8, with the increase of thioglycolic acid dosage, the recovery rate of bismuthinite gradually decreased. -4 mol / L, the recovery rate dropped to 41%; the amount of persulfate increased to 6×10 -4 mol / L, the recovery rate of bismuthinite remained stable at 38%, and further increasing the dosage of AMT had little effect on the inhibition of bismuthinite; the recovery rate of molybdenite decreased slightly with the increase of the dosage of thioglycolic acid, but still remained above 92%, indicating that sodium thioglycolate had a weak inhibitory effect on molybdenite.

[0055] Example 7

[0056] Take the mixed ore (molybdenite: bismuthite = 1:1) and 35mL of ultrapure water and add them to a 40mL hanging tank flotation machine. Stir and adjust the slurry at a speed of 1758r / min to make the slurry fully dispersed. Figure 1 Add pH adjuster, oxidant, inhibitor, collector and frother, adjust pH to 8, oxidant is ammonium persulfate, inhibitor is citric acid, collector is O-isopropyl-N-ethylthiocarbamic acid (20 mg / L), frother is methyl amyl alcohol (10 mg / L), the ratio of ammonium persulfate to citric acid is 1:5, 1:3, 1:1, 3:1, 5:1. After adding the reagents, stir for 3 minutes respectively, and aerate and float to obtain foam product and bottom product. Filter, dry and weigh the foam product and bottom product respectively, and calculate the recovery rate. The results are as follows Figure 8 shown.

[0057] like Figure 8 It can be seen that, as the amount of citric acid decreases, the Bi grade in the foam product increases first and then decreases. When the ratio of ammonium persulfate to citric acid is 1:1, the Bi grade in the foam product reaches the maximum value. When the ratio is 5:1, the Bi grade in the foam product reaches the minimum value of 5.1%. The molybdenum grade in the foam product is above 50%, and the recovery rate of molybdenite remains above 90% in the entire ratio range.

[0058] Example 8

[0059] Take the mixed ore (molybdenite: bismuthite = 1:1) and 35mL of ultrapure water and add them to a 40mL hanging tank flotation machine. Stir and adjust the slurry at a speed of 1758r / min to make the slurry fully dispersed. Figure 1 Add reagents, adjust the pH value to 8, the oxidant is ammonium persulfate, the inhibitor is citric acid, the collector is O-isopropyl-N-ethylthiocarbamic acid (20 mg / L), the foaming agent is methyl amyl alcohol (10 mg / L), the ratio of ammonium persulfate to citric acid is 3:1, and the dosage is 5×10 -5 , 1×10 -4 , 2×10 -4 , 3×10 -4 , 4×10 -4 , 1×10 -3 mol / L. After adding the reagent, stir for 3 minutes respectively. After stirring, aerate and float to obtain foam products and bottom products. Filter, dry and weigh the foam products and bottom products respectively, and calculate the recovery rate. The results are as follows: Fig. 9 shown.

[0060] like Fig. 9 It can be seen that when the ratio of ammonium persulfate to citric acid is constant, as the dosage of both increases, the Bi grade in the foam product decreases first and then increases. -4 mol / L, the Bi grade in the foam product reaches the minimum value of 1.10%; and the molybdenum grade in the foam product also shows a trend of rising and then falling with the increase of the dosage of the reagent, but the recovery rate of molybdenite remains above 90% in the entire dosage range.

[0061] The basic principles and main features of the present invention and the advantages of the present invention are shown and described above. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention.

[0062] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A method for flotation separation of molybdenite and bismuthinite, characterized in that: The following steps are involved: S1. Sorting and crushing the ore samples containing molybdenite and bismuthinite, and grinding them to a particle size range of 0.038-0.074 mm as flotation samples; S2, mixing the mineral with water to form a slurry, and adjusting the slurry to a certain pH value; S3, adding a certain amount of oxidant to the slurry and stirring; S4. Add a certain amount of inhibitor into the slurry and stir it; S5. Add a certain amount of collector into the slurry and stir it; S6. Add a certain amount of foaming agent into the slurry and stir it; S7, subjecting the ore pulp obtained in step S6 to froth flotation, filtering, drying, and testing the froth product and the bottom product after flotation, respectively, and calculating the recovery rate.

2. A method for flotation separation of molybdenite and bismuthinite according to claim 1, characterized in that: In the S2, a pH regulator is used to adjust the pH value of the slurry and control it between 4 and 12; the pH regulator is hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid or lime, sodium carbonate, sodium hydroxide.

3. A method for flotation separation of molybdenite and bismuthinite according to claim 1, characterized in that: The oxidant in S3 is any one or a combination of ammonium persulfate, potassium permanganate, calcium hypochlorite and hydrogen peroxide. The certain amount of oxidant is 0 to 100 mg / L, and the stirring time is 1 min to 30 min.

4. A method for flotation separation of molybdenite and bismuthinite according to claim 1, characterized in that: The inhibitor in S4 is any one or a combination of citric acid, L-cysteine, AMT and thioglycolic acid, and the molecular structure of AMT is:

5. A method for flotation separation of molybdenite and bismuthinite according to claim 4, characterized in that: The amount of inhibitor added to S4 is 3×10 -6 mol / L~2×10 -2 mol / L, stirring and slurrying time is 1 to 10 minutes.

6. A method for flotation separation of molybdenite and bismuthinite according to claim 1, characterized in that: The ratio of the oxidant to the inhibitor in S3 and S4 is 20:1 to 1:20; the dosage of both is 6×10 -6 ~8×10 -2 mol / L.

7. A method for flotation separation of molybdenite and bismuthinite according to claim 1, characterized in that: The collector in S5 is any one or a combination of O-isopropyl-N-ethylthiocarbamate, non-polar oil and isobutyl xanthate, the dosage of the collector is 1-200 mg / L, and the stirring and slurrying time is 1-6 min.

8. The method for flotation separation of molybdenite and bismuthinite according to claim 1, characterized in that: The collector components are in the following proportions: 20 to 75 parts of O-isopropyl-N-ethylthiocarbamic acid, 5 to 20 parts of non-polar oil, and 20 to 60 parts of isobutyl xanthate.

9. A method for flotation separation of molybdenite and bismuthinite according to claim 1, characterized in that: The foaming agent in S6 is any one of eucalyptus oil, methyl amyl alcohol, and alkyl polypropylene glycol ether, or a combination of several of them; and the dosage of the foaming agent is: 1-100 mg / L.

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