Combined collecting agent and application thereof in reverse flotation desilicication of potassium feldspar

Abstract

The invention discloses a combined collecting agent and application of the combined collecting agent in reverse flotation desilicication of potassium feldspar, and belongs to the technical field of mineral processing engineering. The combined collecting agent is composed of sodium oleate and hexadecyl trimethyl ammonium chloride. When the total dosage of the agent is 1 * 10 <-4 > mol / L to 6 * 10 <-4 > mol / L, the pH value is 10.0, and the molar ratio of hexadecyl trimethyl ammonium chloride to sodium oleate in the combined collecting agent is 1: 3-1: 2, efficient reverse flotation separation of the potassium feldspar and the quartz can be achieved. The combined collecting agent has the advantages of being high in collecting capacity, low in production cost, small in agent dosage, good in selectivity, environmentally friendly, safe and the like, and the separation effect and the economic benefit are both considered. According to the method, the sodium oleate and hexadecyl trimethyl ammonium chloride combined collecting agent is used for flotation separation of the potassium feldspar and the quartz.

Description

Technical Field

[0001] The invention belongs to the technical field of mineral processing engineering, and in particular relates to a combined collector and application thereof in reverse flotation desiliconization of potassium feldspar. Background Art

[0002] With the rapid development of my country's national economy and the technological progress of modern agriculture, the demand for fertilizers has increased dramatically, and potash fertilizer is one of the main fertilizers required for crop growth, but a large part of my country's potash fertilizer needs to rely on imports, which seriously affects the development of my country's agriculture. my country's water-soluble potassium resource reserves account for only 2.2% of the global reserves, and water-soluble potassium resources are in short supply. Compared with water-soluble potassium resources, potassium feldspar is a non-water-soluble potassium mineral resource with large reserves, easy recovery and excellent quality, and has become an important source of raw materials for potash fertilizer production. However, natural potassium feldspar contains a large amount of siliceous gangue minerals (such as quartz), resulting in a low potassium content, which is difficult to meet the requirements of commercial potash fertilizer production for raw materials. Therefore, efficient sorting and quality improvement of potassium feldspar ore is of great significance to the sustainable development of the potash fertilizer industry.

[0003] Quartz is a typical silicate gangue mineral, often associated with potassium feldspar. Since quartz and potassium feldspar have similar physical and chemical properties, such as similar density, and both minerals are non-magnetic, gravity separation and magnetic separation methods cannot be used to separate the two. Flotation is still an effective method for separating potassium feldspar. At present, the collectors used to separate potassium feldspar are mainly cationic amine collectors such as alkylamines and quaternary ammonium salts. However, these collectors have poor selectivity and large dosage, making it difficult to effectively separate potassium feldspar. In addition, the flotation separation of potassium feldspar using a single amine collector usually requires strong acidic conditions, resulting in severe corrosion of industrial production equipment and high maintenance costs. At the same time, a large amount of acidic wastewater will be generated, polluting the environment. Therefore, it is urgent to develop new and efficient collectors to enhance the flotation separation of potassium feldspar and quartz. Summary of the invention

[0004] The first object of the present invention is to provide a combined collector capable of realizing efficient flotation separation of potassium feldspar and quartz.

[0005] The second object of the present invention is to provide the application of the above-mentioned combined collector in the reverse flotation desiliconization of potassium feldspar, which is to use the combination of anionic sodium oleate and cationic hexadecyltrimethylammonium chloride for mineral flotation.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0007] The first aspect of the present invention provides a combined collector, which is composed of hexadecyltrimethylammonium chloride and sodium oleate in a molar ratio of 1:3 to 1:2.

[0008] Preferably, the combined collector is composed of hexadecyltrimethylammonium chloride and sodium oleate in a molar ratio of 1:2.

[0009] Preferably, the total amount of the combined collector is 1×10 -4 mol / L~6×10 -4 mol / L.

[0010] The combined collector provided by the present invention can complement each other according to their own unique properties, thereby producing a synergistic effect, becoming a good collector with excellent collecting ability and high selectivity, and providing a reagent selection for improving the desiliconization of potassium feldspar by reverse flotation.

[0011] The second aspect of the present invention provides the use of the above-mentioned combined collector in reverse flotation desiliconization of potassium feldspar, which specifically comprises the following steps:

[0012] Step 1: Grinding

[0013] Grinding the potassium feldspar ore or the potassium feldspar and quartz mineral samples, and obtaining the ore sample with a particle size less than 150 mesh after sieving;

[0014] Step 2: Mixing the slurry

[0015] Mix the ore sample with water, add it into the flotation equipment, and stir it evenly to obtain a slurry with a mass concentration of 5 to 30%;

[0016] Step 3: Flotation

[0017] At room temperature, adding a pH adjuster to the slurry to adjust the pH of the slurry to 2-12, stirring evenly to obtain a slurry with a pH of 2-12;

[0018] First, add the collector sodium oleate to the ore pulp with a pH of 2 to 12 and stir evenly;

[0019] Then add the collector hexadecyltrimethylammonium chloride into the ore pulp and stir evenly; then flotation separation is performed.

[0020] Preferably, in step 2, the flotation equipment is a stirring flotation machine with a rotation speed of 1500 to 2100 r / min.

[0021] Preferably, in step 3, the pH adjuster is a 0.01-0.1 mol / L nitric acid solution or a 0.01-0.1 mol / L sodium hydroxide solution.

[0022] Preferably, in step 3, the stirring rate is 1500-2100 r / min, and the stirring time is 2-3 min.

[0023] Preferably, in step 3, the pH value is 10.0.

[0024] Preferably, in step 3, the flotation separation step uses a reverse flotation device with a rotation speed of 1500 to 2100 r / min and a flotation time of 3 to 5 min.

[0025] Preferably, in step 3, the total amount of the collector is 1×10 -4 mol / L~6×10 -4 mol / L.

[0026] The invention relates to a combined collector and application thereof in reverse flotation desiliconization of potassium feldspar. Through reverse flotation, potassium feldspar concentrate with a potassium feldspar recovery rate greater than 87% and a K2O grade higher than 11% can be obtained.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] 1. The present invention develops a method for separating potassium feldspar and quartz by using a combined collector of sodium oleate and hexadecyltrimethylammonium chloride. In the flotation process, sodium oleate and hexadecyltrimethylammonium chloride are added in sequence as collectors. Since sodium oleate and hexadecyltrimethylammonium chloride are anionic collectors and cationic collectors, respectively, the two collectors have different ionic properties in the solution. The anionic sodium oleate and the cationic hexadecyltrimethylammonium chloride are electrically complementary and synergistic in the solution system, which is manifested in that the collectors with opposite electrical properties can produce a charge compensation effect and are prone to molecular association. The combined collectors can selectively co-adsorb on the quartz surface, efficiently collect quartz minerals, and achieve efficient removal of quartz from potassium feldspar through reverse flotation.

[0029] 2. The sodium oleate and hexadecyltrimethylammonium chloride involved in the present invention are used in combination to form an anion-cation combination collector, which realizes the efficient separation of potassium feldspar and quartz. Potassium feldspar concentrate with a potassium feldspar recovery rate of more than 87% and a K2O grade of more than 11% can be obtained through reverse flotation.

[0030] 3. The sodium oleate and hexadecyltrimethylammonium chloride combined collector of the present invention is miscible with water, non-toxic and pollution-free, has good chemical stability, and has the advantages of strong collecting ability, low production cost, small amount of reagents used, good selectivity, environmental protection and safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 The present invention is a process flow chart of a combined collector for separating quartz and feldspar according to an embodiment of the present invention. DETAILED DESCRIPTION

[0032] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] The reagents used in the following examples are solid hexadecyltrimethylammonium chloride and deionized water prepared into a solution with a concentration of 0.01-0.05 mol / L, solid sodium oleate and deionized water prepared into a solution with a concentration of 0.01-0.05 mol / L. The pH adjusters used include nitric acid and sodium hydroxide, both prepared into a solution with a concentration of 0.01-0.1 mol / L.

[0034] Example 1

[0035] Application of a combined collector in reverse flotation desiliconization of potassium feldspar, the process is as follows Figure 1 As shown, the specific steps include:

[0036] Step 1: Grinding

[0037] The quartz and potassium feldspar ore samples are ground and sieved to obtain quartz and potassium feldspar ore samples with a particle size of 400 to 150 meshes.

[0038] Step 2: Mixing the slurry

[0039] A mixture of quartz and potassium feldspar (mass ratio 1:1) and water were added to the flotation equipment, mixed and stirred at a speed of 1500r / min for 1min to obtain a flotation slurry with a solid concentration of 50g / L.

[0040] Step 3: Flotation

[0041] At room temperature, sodium hydroxide solution was added to the slurry to adjust the pH value of the slurry to 11.0, and the mixture was mixed and stirred at a speed of 1500 r / min for 1 min to obtain a slurry with a pH value of 11.0.

[0042] Add the collector sodium oleate to the slurry with pH = 11.0, and mix and stir for 2 minutes at a speed of 1500r / min. Then add the collector hexadecyl trimethyl ammonium chloride to the slurry, and mix and stir for 2 minutes at a speed of 1500r / min. The molar ratio of hexadecyl trimethyl ammonium chloride to sodium oleate in the combined collector is 1:2, and the total dosage of the agent is 1×10 -4 mol / L. Then flotation separation, scraping bubbles every 10s, scraping bubbles for 6min. After flotation, the product in the tank, i.e. concentrate, and the foam product, i.e. tailings, are dried and weighed respectively, and samples are taken for K2O grade testing, and the recovery rate is calculated. The recovery rate of potassium feldspar in the concentrate is 96.93%, and the K2O grade is 6.59%.

[0043] Example 2

[0044] Steps 1-2 are the same as those in Example 1.

[0045] Step 3: Flotation

[0046] At room temperature, sodium hydroxide solution was added to the slurry to adjust the pH value of the slurry to 10.0, and the mixture was mixed and stirred at a speed of 1500 r / min for 1 min to obtain a slurry with a pH value of 10.0.

[0047] Add the collector sodium oleate to the slurry with pH = 10.0, and mix and stir for 2 minutes at a speed of 1500r / min. Then add the collector hexadecyl trimethyl ammonium chloride to the slurry, and mix and stir for 2 minutes at a speed of 1500r / min. The molar ratio of hexadecyl trimethyl ammonium chloride to sodium oleate in the combined collector is 1:2, and the total dosage of the agent is 5×10 -4 mol / L. Then flotation separation, scraping bubbles every 10s, scraping bubbles for 3min. After flotation, the product in the tank, i.e. concentrate, and the foam product, i.e. tailings, are dried and weighed respectively, and samples are taken for K2O grade testing, and the recovery rate is calculated. The recovery rate of potassium feldspar in the concentrate is 87.79%, and the K2O grade is 11.66%.

[0048] Example 3

[0049] Steps 1 and 2 are the same as steps 1 and 2 in Example 1.

[0050] Step 3: Flotation

[0051] At room temperature, 0.01 mol / L nitric acid solution was added to the slurry to adjust the pH value of the slurry to 6.5, and the mixture was mixed and stirred at a speed of 1500 r / min for 1 min to obtain a slurry with a pH value of 6.5.

[0052] Add the collector sodium oleate to the slurry with pH=6.5, and stir at a speed of 1500r / min for 2min. Then add the collector hexadecyl trimethyl ammonium chloride to the slurry, and stir at a speed of 1500r / min for 2min. The molar ratio of hexadecyl trimethyl ammonium chloride to sodium oleate in the combined collector is 1:3, and the total dosage of the agent is 5×10 -4 mol / L. Then flotation separation, scraping bubbles every 10s, scraping bubbles for 3min. After flotation, the product in the tank, i.e. concentrate, and the foam product, i.e. tailings, are dried and weighed respectively, and samples are taken for K2O grade testing, and the recovery rate is calculated. The recovery rate of potassium feldspar in the concentrate is 97.94%, and the K2O grade is 6.55%.

[0053] Example 4

[0054] Steps 1 and 2 are the same as steps 1 and 2 in Example 1.

[0055] Step 3: Flotation

[0056] At room temperature, 0.05 mol / L nitric acid solution was added to the slurry to adjust the pH value of the slurry to 4.0, and the mixture was mixed and stirred at a speed of 1500 r / min for 1 min to obtain a slurry with a pH value of 4.0.

[0057] Add the collector sodium oleate to the slurry with pH = 4.0, and mix and stir for 2 minutes at a speed of 1500r / min. Then add the collector hexadecyl trimethyl ammonium chloride to the slurry, and mix and stir for 2 minutes at a speed of 1500r / min. The molar ratio of hexadecyl trimethyl ammonium chloride to sodium oleate in the combined collector is 1:2, and the total dosage of the agent is 3×10 -4 mol / L. Then flotation separation, scraping bubbles every 10s, scraping bubbles for 3min. After flotation, the product in the tank, i.e. concentrate, and the foam product, i.e. tailings, are dried and weighed respectively, and samples are taken for K2O grade testing, and the recovery rate is calculated. The recovery rate of potassium feldspar in the concentrate is 92.03%, and the K2O grade is 6.64%.

[0058] Comparative Example 1

[0059] The difference between Comparative Example 1 and Example 2 is that only the collector sodium oleate is added.

[0060] The pulp was floated according to the method of Comparative Example 1, and the potassium feldspar recovery rate in the flotation concentrate was 95.37%, while the K2O grade was only 6.56%.

[0061] Comparative Example 2

[0062] The difference between Comparative Example 2 and Example 2 is that only the collector hexadecyltrimethylammonium chloride is added.

[0063] The pulp was floated according to the method of Comparative Example 2, and the K2O grade in the flotation concentrate was 10.38%, while the potassium feldspar recovery rate was only 36.47%.

[0064] Compared with the use of sodium oleate or hexadecyltrimethylammonium chloride as a collector alone, the use of sodium oleate and hexadecyltrimethylammonium chloride as a combined collector can obtain a flotation potassium feldspar concentrate with a higher lepidolite recovery rate (greater than 87%) and a higher K2O grade (greater than 11%).

[0065] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any modifications, equivalent substitutions and improvements made by any technician familiar with the technical field within the technical scope disclosed by the present invention and within the spirit and principle of the present invention should be covered by the protection scope of the present invention.

Claims

1. A combined collector, characterized in that: The combined collector is composed of hexadecyltrimethylammonium chloride and sodium oleate in a molar ratio of 1:3 to 1:

2.

2. A combined collector according to claim 1, characterized in that: The combined collector is composed of hexadecyltrimethylammonium chloride and sodium oleate in a molar ratio of 1:

2.

3. A combined collector according to claim 1, characterized in that: The total dosage of the combined collector is 1×10 -4 mol / L~6×10 -4 mol / L.

4. Use of the combined collector according to any one of claims 1 to 3 in reverse flotation desiliconization of potassium feldspar, characterized in that: The specific steps include: Step 1: Grinding: Grind the potassium feldspar ore or the potassium feldspar and quartz mineral samples, and obtain the ore sample with a particle size of less than 150 mesh after screening; Step 2: Slurry preparation: Mix the ore sample with water, add it to the flotation equipment, and stir it evenly to obtain a slurry with a mass concentration of 5-30%; Step 3: flotation: at room temperature, add a pH adjuster to the pulp to adjust the pH of the pulp to 2-12, stir evenly, and obtain a pulp with a pH of 2-12; first add a collector sodium oleate to the pulp with a pH of 2-12, stir evenly; then add a collector hexadecyltrimethylammonium chloride to the pulp, stir evenly; then flotation separation.

5. The use according to claim 4, characterized in that: In step 2, the flotation equipment is a stirring flotation machine with a rotation speed of 1500 to 2100 r / min.

6. The use according to claim 4, characterized in that: In step 3, the pH adjuster is a 0.01-0.1 mol / L nitric acid solution or a 0.01-0.1 mol / L sodium hydroxide solution.

7. The use according to claim 4, characterized in that: In step 3, the stirring rate is 1500-2100 r / min, and the stirring time is 2-3 min.

8. The use according to claim 4, characterized in that: In step 3, the pH value is 10.

0.

9. The use according to claim 4, characterized in that: In step 3, the flotation separation step adopts reverse flotation equipment with a rotation speed of 1500-2100 r / min and a flotation time of 3-5 min.

10. The use according to claim 4, characterized in that: In step 3, the total amount of the collector is 1×10 - 4 mol / L~6×10 -4 mol / L.

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