Cassiterite collecting agent and cassiterite flotation separation method

Abstract

The invention discloses a cassiterite collecting agent and a cassiterite flotation separation method, and belongs to the technical field of cassiterite flotation separation. According to the method, 3-(dodecyl sulfenyl) propionic acid serves as the collecting agent, and the collecting agent can achieve efficient flotation separation of cassiterite and gangue minerals under the condition that an activating agent is not added. In addition, the collecting agent has high anti-interference capacity on common inevitable ions such as calcium and magnesium, has the advantages of being easy to synthesize, free of activating agents and foaming agents, high in selectivity, high in collecting capacity, wide in applicable pH range and the like, and has important significance on efficient development and utilization of cassiterite.

Description

Technical Field

[0001] The present invention belongs to the technical field of cassiterite flotation separation, and specifically relates to a cassiterite collector and a cassiterite flotation separation method. Background Art

[0002] Tin is widely used in industrial production, food packaging, medical treatment and other fields due to its excellent physical and chemical properties such as low melting point, high stability, non-toxicity, etc. Cassiterite is the main source of tin. Cassiterite is brittle and easily over-crushed. Therefore, compared with gravity separation, flotation has a wider application range and stronger adaptability, and is one of the main methods for cassiterite ore dressing. An efficient collector is the key to effectively recovering cassiterite. At present, the main cassiterite collectors are fatty acids, arsonic acids and hydroxamic acids. Fatty acid collectors have strong collecting ability, but poor selectivity, large dosage of reagents, and usually need to add regulators for use; Arsonic acid collectors have high selectivity for cassiterite and remain effective in a wide pH range, but they have been gradually phased out by the mineral processing industry due to their high production cost and environmental risks; Hydroxamic acids also have good selectivity for cassiterite, but they have high cost, large dosage of reagents, are sensitive to inevitable ions, and often need to be combined with heavy metal ions such as Pb 2+ etc. as activators for combined use. Therefore, developing a new type of collector with high selectivity, high collecting ability and strong anti-interference ability against inevitable ions has important economic value and significance. Summary of the Invention

[0003] To solve the defects existing in the above-mentioned prior art, the present invention provides a cassiterite collector and a cassiterite flotation separation method. The present invention uses 3-(dodecylthio)propionic acid as a collector, and this collector can achieve efficient flotation separation of cassiterite and gangue minerals without adding an activator. In addition, this collector has strong anti-interference ability against common inevitable ions such as calcium and magnesium, and has the characteristics of simple synthesis, no need for an activator, no need for a foaming agent, high selectivity, strong collecting ability, wide applicable pH range, etc., which has important significance for the efficient development and utilization of cassiterite.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] One of the technical solutions of the present invention: Provide an application of 3-(dodecylthio)propionic acid in a cassiterite collector.

[0006] 3-(Dodecylthio)propionic acid contains both a sulfhydryl group and a carboxyl group, which can chemically react with Sn to form a stable five-membered ring adsorption configuration, forming a monolayer adsorption on the cassiterite surface and effectively improving the hydrophobicity of the cassiterite surface. Since this collector mainly forms a weak hydrogen bond with gangue minerals such as quartz, it is very easy to desorb during strong stirring, so the surface of the gangue minerals still has strong hydrophilicity. In addition, this reagent has weak activity towards calcium, magnesium and other ions. Therefore, it has strong resistance to interference from calcium, magnesium and other ions, thus realizing the efficient flotation separation of cassiterite and gangue minerals.

[0007] The second technical solution of the present invention: Provide a method for flotation separation of cassiterite, including the following steps:

[0008] Prepare the ore containing cassiterite into pulp, adjust the pH value to 4.0 - 8.0, and then use 3-(dodecylthio)propionic acid as the collector for ore dressing to obtain cassiterite concentrate.

[0009] Preferably, no activator and frother are added during the ore dressing stage.

[0010] Preferably, the ore powder used to prepare the pulp is an ore powder in which particles with a particle size not exceeding 0.074 mm account for 75 - 85 wt.%.

[0011] Preferably, the substance used to adjust the pH value is a 1 - 2 wt.% HCl solution or a 1 - 2 wt.% NaOH solution.

[0012] Preferably, the process of the ore dressing is one roughing, two scavengings and three cleanings.

[0013] Through the preferred ore dressing process of the present invention, cassiterite concentrate with a tin grade of 5 - 8% and a tin recovery rate of 70 - 90% can be obtained.

[0014] More preferably, in the roughing stage, 400 - 800 g of the above-mentioned 3-(dodecylthio)propionic acid is added per ton of ore powder.

[0015] Further preferably, in the roughing stage, 3-(dodecylthio)propionic acid is added in the form of a solution with a mass concentration of 0.2 - 0.5%.

[0016] More preferably, each time scavenging is carried out, 3-(dodecylthio)propionic acid is added, and the addition amount is 80 - 200 g per ton of ore powder.

[0017] Further preferably, each time scavenging is carried out, 3-(dodecylthio)propionic acid is added in the form of a solution with a mass concentration of 0.2 - 0.5%.

[0018] The beneficial technical effects of the present invention are as follows:

[0019] The present invention uses 3-(dodecylthio)propionic acid as a collector for cassiterite. This collector can significantly improve the selective separation of cassiterite from gangue, especially has a remarkable effect on reducing the silicon content in tin concentrate, and can provide high-quality raw materials for subsequent tin chemical production.

[0020] Compared with the current collectors, the collector provided by the present invention has the advantages of not requiring the use of activators and frothers, strong collecting ability, strong selectivity, wide applicable pH range, strong resistance to ion interference, and simple process. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a flow chart of the flotation separation of cassiterite in the embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0022] Now, various exemplary embodiments of the present invention will be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, characteristics, and implementation schemes of the present invention. It should be understood that the terms used in the present invention are only for describing specific embodiments and are not used to limit the present invention.

[0023] It should be noted that the parts not described in detail in the present invention are all conventional operation means in the art and are not the focus of the present invention.

[0024] In addition, for the numerical ranges in the present invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any intermediate value within any stated value or stated range, as well as each smaller range between any other stated value or intermediate value within the stated range, is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded from the range.

[0025] Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention pertains. Although the present invention only describes preferred methods and materials, any methods and materials similar or equivalent to those described herein can also be used in the implementation or testing of the present invention.

[0026] Regarding the use of "comprising", "including", "having", "containing", etc. in this article, they are all open-ended terms, that is, they are meant to include but not be limited to.

[0027] The flow chart of the flotation separation of cassiterite in the embodiment of the present invention is shown in Figure 1 ; all raw materials involved in the embodiments of the present invention are commercially available products, and the step parameters not mentioned in the embodiments of the present invention can be obtained by using conventional technical means in the art.

[0028] Example 1

[0029] Flotation of desulfurized tin ore:

[0030] In this embodiment, the chemical composition of the desulfurized tin ore includes (mass percentage): the Sn content is 0.80%, the Fe content is 2.72%, the S content is 0.27%, the Al2O3 content is 19.85%, the SiO2 content is 65.27%, the CaO content is 1.20%, and the MgO content is 0.55%.

[0031] (1) Crushing and grinding: First, the desulfurized tin ore is crushed by a jaw crusher to less than 2 mm, and then the crushed ore is ground by a ceramic ball mill to a particle size less than 0.074 mm accounting for 85% by mass.

[0032] (2) First rough selection: The ore powder obtained in step (1) is formulated into a pulp with a mass concentration of 25%, then a NaOH solution with a mass percentage concentration of 1% is added to the pulp to adjust the pH value of the pulp to 7, the pulp conditioning time is 3 min, and then a collector solution of 3-(dodecylthio)propionic acid with a mass percentage concentration of 0.5% (500 g of 3-(dodecylthio)propionic acid is added per ton of ore powder) is added, the action time is 4 min, and then aeration and flotation skimming are carried out to obtain a rough selection concentrate and a rough selection tailing.

[0033] (3) Two scavenging operations: The rough selection tailing in step (2) is subjected to two scavenging operations. Each scavenging operation adds a collector solution of 3-(dodecylthio)propionic acid with a mass percentage concentration of 0.5% (100 g of 3-(dodecylthio)propionic acid is added per ton of ore powder), the action time is 3 min, the concentrate obtained from each scavenging operation is sequentially returned to the previous process to form a closed circuit, and the tailing obtained after the second scavenging operation is the final calcium-containing tailing.

[0034] (4) Three cleaning operations: The rough selection concentrate in step (2) is subjected to three cleaning operations. The cleaning tailings each time are sequentially returned to the previous process to form a closed circuit, and the concentrate obtained after the three cleaning operations is the final cassiterite concentrate.

[0035] Using 3-(dodecylthio)propionic acid as the collector, through one rough selection, two scavenging operations, and three cleaning operation processes, a cassiterite concentrate with a tin grade of 7.5% and a tin recovery rate of 80.2% can be finally obtained.

[0036] Example 2

[0037] Flotation of desulfurized tin ore:

[0038] In this embodiment, the chemical composition of the desulfurized tin ore includes (mass percentage): the Sn content is 0.92%, the Fe content is 2.22%, the S content is 0.30%, the Al2O3 content is 17.83%, the SiO2 content is 66.04%, the CaO content is 1.23%, and the MgO content is 0.34%.

[0039] (1) Crushing and grinding: First, the desulfurized tin ore is crushed by a jaw crusher to less than 2 mm, and then the crushed ore is ground by a ceramic ball mill to a particle size of less than 0.074 mm accounting for 80% by mass.

[0040] (2) First rough selection: The ore powder obtained in step (1) is formulated into a pulp with a mass concentration of 30%, and then a HCl solution with a mass percentage concentration of 2% is added to the pulp to adjust the pH value of the pulp to 6. The pulp conditioning time is 3 min. Then, a collector solution of 3-(dodecylthio)propionic acid with a mass percentage concentration of 0.5% (600 g of 3-(dodecylthio)propionic acid is added per ton of ore powder) is added to the pulp, and the action time is 3 min. Then, air is inflated and froth flotation is carried out to obtain rough selection concentrate and rough selection tailings.

[0041] (3) Two-stage scavenging: The rough selection tailings in step (2) are subjected to two-stage scavenging operations. Each scavenging operation adds a collector solution of 3-(dodecylthio)propionic acid with a mass percentage concentration of 0.5% (100 g of 3-(dodecylthio)propionic acid is added per ton of ore powder), and the action time is 3 min. The concentrate obtained from each scavenging operation is sequentially returned to the previous process to form a closed circuit. The tailings obtained after the two-stage scavenging operation are the final calcium-containing tailings.

[0042] (4) Three-stage cleaning: The rough selection concentrate in step (2) is subjected to three-stage cleaning operations. The cleaning tailings from each stage are sequentially returned to the previous process to form a closed circuit. The concentrate obtained after the three-stage cleaning operation is the final cassiterite concentrate.

[0043] Using 3-(dodecylthio)propionic acid as the collector, through the process of one rough selection, two scavengings, and three cleanings, cassiterite concentrate with a tin grade of 6.4% and a tin recovery rate of 87% can be finally obtained.

[0044] Comparative Example 1

[0045] Flotation of desulfurized tin ore:

[0046] Compared with Example 1, the difference is only that the collector in steps (2) and (3) is replaced with an equal mass of fatty acid collector oxidized paraffin soap (also added in the form of a 0.5 wt.% solution), and other conditions are the same as in Example 1.

[0047] Using oxidized paraffin soap as the collector, through the process of one rough selection, two scavengings, and three cleanings, cassiterite concentrate with a tin grade of 2.4% and a tin recovery rate of 35% can be finally obtained.

[0048] Comparative Example 2

[0049] Flotation of desulfurized tin ore:

[0050] Compared with Example 1, the only difference is that the collector in steps (2) and (3) is replaced with an equal mass of fatty acid collector oxidized paraffin soap (also added in the form of a 0.5 wt.% solution), and lead nitrate activator (250 g of activator is added per ton of ore powder) is added before adding the collector in step (2), with an action time of 3 min, and other conditions are the same as in Example 1.

[0051] Using oxidized paraffin soap as the collector, after one rough selection, two scavenging selections, and three cleaning selections, the tin concentrate with a tin grade of 3.2% and a tin recovery rate of 42% can be finally obtained.

[0052] Comparative Example 3

[0053] Flotation of desulfurized tin ore:

[0054] Compared with Example 2, the only difference is that the collector in steps (2) and (3) is replaced with an equal mass of fatty acid collector sodium oleate (also added in the form of a 0.5 wt.% solution), and lead nitrate activator (300 g of activator is added per ton of ore powder) is added before adding the collector in step (2), with an action time of 3 min, and other conditions are the same as in Example 2.

[0055] Using sodium oleate as the collector, after one rough selection, two scavenging selections, and three cleaning selections, the tin concentrate with a tin grade of 2.9% and a tin recovery rate of 45% can be finally obtained.

[0056] Comparative Example 4

[0057] Flotation of desulfurized tin ore:

[0058] Compared with Example 2, the only difference is that the collector in steps (2) and (3) is replaced with an equal mass of hydroxamic acid collector benzohydroxamic acid (also added in the form of a 0.5 wt.% solution), and lead nitrate activator is added before adding the collector in step (2) (100 g of activator is added per ton of ore powder), with an action time of 3 min, and other conditions are the same as in Example 2.

[0059] Using benzohydroxamic acid as the collector, after one rough selection, two scavenging selections, and three cleaning selections, the tin concentrate with a tin grade of 6.3% and a tin recovery rate of 85% can be finally obtained.

[0060] The above-described embodiments are only descriptions of the preferred embodiments of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention should all fall within the protection scope determined by the claims of the present invention.

Claims

Application of 1.3-(dodecylthio)propionic acid as cassiterite collector.

2. A cassiterite flotation separation method, characterized in that: The following steps are involved: The cassiterite-containing ore is prepared into a slurry, and the pH value is adjusted to 4.0-8.0, and then 3-(dodecylthio) propionic acid is used as a collector for mineral processing to obtain a cassiterite concentrate.

3. The cassiterite flotation separation method according to claim 2, characterized in that: No activator or frother is added during the cassiterite flotation separation process.

4. The cassiterite flotation separation method according to claim 2, characterized in that: The ore powder used for preparing the ore slurry is ore powder in which particles with a particle size not exceeding 0.074 mm account for 75 to 85 wt.%.

5. The cassiterite flotation separation method according to claim 2, characterized in that: The substance used for adjusting the pH value is 1-2 wt.% HCl solution or 1-2 wt.% NaOH solution.

6. The cassiterite flotation separation method according to claim 2, characterized in that: The mineral processing includes one roughing, two sweeping and three refining.

7. The cassiterite flotation separation method according to claim 6, characterized in that: In the roughing stage, 400-800 g of the 3-(dodecylthio)propionic acid is added per ton of ore powder.

8. The cassiterite flotation separation method according to claim 7, characterized in that: In the roughing stage, 3-(dodecylthio)propionic acid is added in the form of a solution with a mass concentration of 0.2 to 0.5%.

9. The cassiterite flotation separation method according to claim 6, characterized in that: Collector 3-(dodecylthio) propionic acid is added each time the scavenging is performed, and the added amount is 80-200 g per ton of ore powder.

10. The cassiterite flotation separation method according to claim 9, characterized in that: Each time 3-(dodecylthio)propionic acid is selected, it is added in the form of a solution with a mass concentration of 0.2-0.5%.

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