CN117085848A - Collophanite low-temperature reverse flotation collector and preparation method thereof - Google Patents

Abstract

The invention discloses a collophanite low-temperature reverse flotation collector and a preparation method thereof, and belongs to the technical field of collophanite flotation. The collophanite low-temperature reverse flotation collector disclosed by the invention is prepared from the following raw materials: including linoleic acid, linolenic acid, and gallic acid. The invention generates collophanite low-temperature reverse flotation collector containing two OH and one COOH through esterification reaction of linoleic acid, linolenic acid and gallic acid, the flotation recovery rate in acid ore pulp is reduced by 20-50% compared with the use level before the lipidation reaction, and the concentrate P ₂ O ₅ The grade and recovery rate are obviously improved. The collophanite low-temperature reverse flotation collector can be used for flotation at a low temperature of 5-10 ℃ when flotation foam generated in the flotation process existsShort time, low foam stability, easy defoaming and being beneficial to continuous operation and tail water recovery.

Description

A low-temperature reverse flotation collector of colloidal phosphate rock and its preparation method

Technical field

The invention belongs to the technical field of colloidal phosphate rock flotation, and specifically relates to a low-temperature reverse flotation collector of colloidal phosphate rock and a preparation method thereof.

Background technique

The reverse flotation of colloidal phosphate rock is a process that uses sulfuric acid and phosphoric acid to suppress apatite and uses fatty acids to reverse flotation dolomite. High-efficiency fatty acid collectors are the core factors that affect the separation efficiency. At present, colloidal phosphate reverse flotation rarely uses a single fatty acid collector, but uses a mixture of fatty acids such as oleic acid, such as vegetable oil, gutter oil, etc. There are two problems in the use of these mixed fatty acids: first, the mixed fatty acids dissociate weakly under acidity, resulting in excessive collector dosage; second, excessive collector dosage causes the foam to be too sticky and difficult to defoam. , which brings difficulties to the circulation of return water.

Contents of the invention

In view of the shortcomings of the above-mentioned prior art, the present invention provides a low-temperature reverse flotation collector of colloidal phosphate rock and a preparation method thereof. The present invention uses mixed fatty acids of linoleic acid and linolenic acid as the main raw material for the esterification reaction to form a low-temperature reverse flotation collector for collophosphate rock containing 2-3 OH and one COOH, which is recovered by flotation in acidic slurry. The dosage is reduced by 20-50% compared to before the lipidation reaction.

A low-temperature reverse flotation collector for colloidal phosphate rock is prepared from the following raw materials: including linoleic acid, linolenic acid and gallic acid.

As a preferred embodiment of the present invention, the volume ratio of linoleic acid, linolenic acid and gallic acid is 60-80:20-40:50-70.

As a preferred embodiment of the present invention, the low-temperature reverse flotation collector of collophosphate rock contains 2-3 OH and 1 COOH; wherein the low-temperature reverse flotation collector of collophosphate rock contains 2-3 OH, It can be connected through hydrogen bonds between OH groups to increase the adsorption density of the low-temperature reverse flotation collector of collophosphate rock on the mineral surface.

As a preferred embodiment of the present invention, the preparation method of the low-temperature reverse flotation collector of collophosphate rock includes the following steps:

(1) Mix linoleic acid and linolenic acid to obtain mixed fatty acids;

(2) Add mixed fatty acids to carbon tetrachloride, add gallic acid, and react at 50-90°C to obtain a low-temperature reverse flotation collector for collophosphate rock.

Linoleic acid and linolenic acid are the main components in currently used mixed oils. Compared with the traditional agent oleic acid, they have the characteristics of greater solubility and good dissociation under acidity. The present invention uses linoleic acid and linolenic acid as raw materials, and then Gallic acid is added for esterification reaction to obtain a low-temperature reverse flotation collector for collophosphate rock with better performance. Among them, the specific reaction mechanism of linoleic acid, linolenic acid and gallic acid is:

In formula (1)-(2), R1COOH is linoleic acid molecule, R2COOH is linolenic acid, R1 is CH ₃ (CH ₂ ) ₄ CH＝CHCH ₂ CH＝CH(CH ₂ ) ₇ , R2 is CH ₃ (CH ₂ CH＝CH) ₃ (CH ₂ ) ₇ .

As a preferred embodiment of the present invention, in step (2), the reaction time is 30-45 minutes.

As a preferred embodiment of the present invention, in step (2), the added amount of carbon tetrachloride is 50-70% of the mass sum of linoleic acid and linolenic acid. After the reaction is completed, it is distilled at 70-100°C to remove Carbon tetrachloride.

As a preferred embodiment of the present invention, the low-temperature reverse flotation collector of colloidal phosphate rock is flotated at 5-10°C. The low-temperature reverse flotation collector of colloidal phosphate rock does not affect the flotation performance of the agent in a low-temperature environment (5-10°C), and the foam produced by using the low-temperature reverse flotation collector of colloidal phosphate rock has low viscosity. Easy to defoam.

As a preferred embodiment of the present invention, the low-temperature reverse flotation collector of colloidal phosphate can flotate dolomite at pH 4-6, and at the same time can avoid the interference of calcium and magnesium ions in the slurry, and the low-temperature reverse flotation collector of colloidal phosphate rock can Compared with linoleic acid, linolenic acid or mixed fatty acids of linoleic acid and linolenic acid, the dosage of collector can be reduced by 30-40%.

Compared with the prior art, the beneficial effects of the present invention are:

(1) The present invention generates a low-temperature reverse flotation collector for colloidal phosphate rock containing two OH and one COOH through the esterification reaction of linoleic acid, linolenic acid and gallic acid. The flotation recovery rate in acidic slurry is higher than that of the esterification reaction. Before, the dosage dropped by 20-50%, and the P ₂ O ₅ grade and recovery rate of the concentrate increased significantly.

(2) The low-temperature reverse flotation collector of colloidal phosphate rock can flotate at a low temperature of 5-10°C. Moreover, the flotation foam generated during the flotation process of the colloidal phosphate rock low-temperature reverse flotation collector has a short existence time, low foam stability, and is easy to defoam, which is beneficial to continuous operation and tail water recovery.

Description of the drawings

Figure 1 is a comparative chart of the thickness of the flotation foam layer changing with time under the action of the low-temperature reverse flotation collector of colloidal phosphate rock prepared in Example 1 or the mixed fatty acid of linoleic acid and linolenic acid.

Detailed ways

In order to better illustrate the purpose, technical solutions and advantages of the present invention, the present invention will be further described below with reference to specific embodiments.

Example 1

The preparation method of the low-temperature reverse flotation collector of colloidal phosphate rock includes the following steps:

(1) Mix 6 mL linoleic acid and 4 mL linolenic acid to obtain mixed fatty acids;

(2) Add the mixed fatty acid to 5 mL of carbon tetrachloride, and add 5 mL of gallic acid, and react at 50°C for 45 minutes. After the reaction is completed, distill at 100°C to remove the carbon tetrachloride to obtain low-temperature reverse flotation of colloidal phosphate rock. Collector.

Example 2

The preparation method of the low-temperature reverse flotation collector of colloidal phosphate rock includes the following steps:

(1) Mix 8 mL linoleic acid and 2 mL linolenic acid to obtain mixed fatty acids;

(2) Add the mixed fatty acid to 7 mL of carbon tetrachloride, and add 7 mL of gallic acid, and react at 90°C for 30 minutes. After the reaction is completed, distill at 70°C to remove the carbon tetrachloride to obtain low-temperature reverse flotation of colloidal phosphate rock. Collector.

Comparative example 1

The low-temperature reverse flotation collector of colloidal phosphate rock described in this comparative example is a mixed fatty acid obtained by mixing 6 mL linoleic acid and 4 m linolenic acid.

Effect example 1

This effect example is used to test the foam stability of the collector sample.

Collecting agent sample: low-temperature reverse flotation collector of colloidal phosphate rock described in Example 1-2, mixed fatty acid described in Comparative Example 1.

The foam stability test of this effect example includes the following steps: add 200 mL of deionized water to a 1000 mL graduated cylinder, add 300 mg/L collector sample, inflate with air at a flow rate of 1.2 L/min to generate a foam layer, and observe The thickness of the foam layer changes with time, thus reflecting the stability of the foam layer during the flotation process.

As shown in Figure 1, the thickness of the foam layer under the action of mixed fatty acids is extremely stable, maintaining a thickness of 25-30cm within 10 minutes of measurement; however, after the esterification reaction of the mixed fatty acids, the foam layer thickness as described in Example 1-2 The stability of the foam layer has dropped sharply, from 33cm to less than 10cm in 10 minutes, which has a more obvious defoaming effect, indicating that the low-temperature reverse flotation of colloidal phosphate rock obtained after the esterification reaction The foam of the collector is easy to defoam and has low viscosity, which enhances the fluidity of the foam product.

Effect example 2

This effect example is used to test the grade and recovery rate of concentrate P ₂ O ₅ by collector samples in the flotation process.

The raw ore is selected from: phosphate rock in Jinning area of Yunnan Province. It has the characteristics of high phosphorus, low magnesium and high sesquioxide (R ₂ O ₃ ). It cannot meet the quality standard requirements of phosphate rock for acid processing and is difficult to be directly utilized. Therefore, it is difficult to select colloidal phosphate rock, and the P ₂ O ₅ grade of the raw ore is 18.66%.

Collector sample: Colloidal phosphate rock low-temperature reverse flotation collector described in Example 1-2, mixed fatty acid, linoleic acid, linolenic acid, and gallic acid described in Comparative Example 1.

Reverse flotation process: When the reverse flotation temperature is 10°C, the grinding fineness is -0.074mm, and the mass fraction accounts for 83.6%. The amount of collector sample used in rough reverse flotation separation is 1kg/t, and the reverse flotation sweep Under the condition that the dosage of collector sample is 0.5kg/t, when the raw ore P ₂ O ₅ grade is 18.66%, a closed-circuit process of reverse flotation, 1 coarse, 1 sweep-1 concentrate and medium ore sequential return is used to obtain phosphorus Concentrate, the results are shown in Table 1.

Table 1

The results in Table 1 show that using the low-temperature reverse flotation reagents of Examples 1 and 2, the grade of phosphate concentrate reaches 28-29%, and the recovery rate is between 86-87%. However, when the collector of Comparative Example 1 (a mixed acid of linoleic acid and linolenic acid) was used, the grade of the phosphate concentrate was only 25.22%, indicating that the gangue minerals were not fully flotated and the grade of the concentrate was not significantly improved; using linoleic acid and linolenic acid alone Oleic acid, linolenic acid, gallic acid, and the grade of P ₂ O ₅ in the concentrate cannot be effectively improved. The reverse flotation reagents in Examples 1 and 2 have significant collection capabilities and are suitable for reverse flotation of phosphate rock. The reason is that there are COOH groups in the esterification reagent formed after the reaction of linoleic acid and linolenic acid with gallic acid. , which can capture dolomite and calcite gangue; and the benzene ring of the esterification agent contains two OH groups. When the agent is adsorbed on the dolomite surface, adjacent agent molecules can form intermolecular hydrogen bonds through the OH groups. function, thereby strengthening the aggregation of the agent, increasing the adsorption density of the agent on the mineral surface, and improving the flotation efficiency; in addition, the COC ether group is introduced into the molecule, which improves the solubility of the agent, allowing the agent to adapt to the acidic environment, and the ether group has a certain Hydrophilicity can reduce the viscosity of foam and facilitate defoaming.

Effect example 3

This effect example is used to test the grade and recovery rate of concentrate P ₂ O ₅ by collector samples at different flotation temperatures.

The raw ore is selected from: Flotation test of low- and medium-grade colloidal phosphate ore in three layers of Fangmashan, Hubei Province. The P ₂ O ₅ grade of the raw ore is 20.14%. Its SiO ₂ , MgO, and CaO contents are high. The main gangue minerals are quartz, dolomite and Albite.

Collecting agent sample: low-temperature reverse flotation collector of colloidal phosphate rock described in Example 1-2, mixed fatty acid, linoleic acid, and linolenic acid described in Comparative Example 1.

Flotation process: 500g of raw ore is used for each test, and flotation is carried out at a grinding fineness of 85%-200 mesh. The amount of roughing collector is 500g/t, the amount of sulfuric acid inhibitor is 18kg/t, and 1 coarse- In the process of 1 fine-1 sweep flotation, the middle ore is returned sequentially, 2kg/t of sulfuric acid and 200g/t of collector are added to the fine selection. The results are shown in Table 2.

Table 2

The results in Table 2 show that for the low- and medium-grade colloidal phosphate ore in the third layer of Fangmashan, Hubei Province, using the chemicals in Examples 1 and 2, P ₂ O ₅ grade >28% can be obtained at 5°C and 10°C, with a recovery rate of 80%. The above phosphate concentrate, but using Comparative Example 1, linolenic acid, and linoleic acid, it is difficult to improve the grade of the phosphate concentrate at 5°C, 10°C, and 20°C, and the P ₂ O ₅ grade is between 20-24% and cannot be Obtain high-grade phosphate concentrate.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and do not limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that The technical solution of the present invention may be modified or equivalently substituted without departing from the essence and scope of the technical solution of the present invention.

Claims (8)

1. The collophanite low-temperature reverse flotation collector is characterized by comprising the following raw materials: including linoleic acid, linolenic acid, and gallic acid.

2. The collophanite low temperature reverse flotation collector as claimed in claim 1, wherein the volume ratio of linoleic acid, linolenic acid and gallic acid is 60-80:20-40:50-70.

3. The collophanite low temperature reverse flotation collector as claimed in claim 1, wherein the collophanite low temperature reverse flotation collector contains 2-3 OH and 1 COOH.

4. A collophanite low temperature reverse flotation collector as claimed in any one of claims 1 to 3 wherein the collophanite low temperature reverse flotation collector is subjected to flotation at a temperature of from 5 to 10 ℃.

5. A collophanite low temperature reverse flotation collector as claimed in any one of claims 1 to 3, wherein the collophanite low temperature reverse flotation collector floats dolomite within ph=4 to 6.

6. A method for preparing a collophanite low temperature reverse flotation collector as claimed in any one of claims 1 to 3, comprising the steps of:

(1) Mixing linoleic acid and linolenic acid to obtain mixed fatty acid;

(2) Adding mixed fatty acid into carbon tetrachloride, adding gallic acid, and reacting at 50-90 ℃ to obtain the collophanite low-temperature reverse flotation collector.

7. The method for preparing the collophanite low temperature reverse flotation collector as claimed in claim 6, wherein the reaction time is 30-45 minutes.

8. The method for preparing a collophanite low temperature reverse flotation collector as claimed in claim 6, wherein in the step (2), the carbon tetrachloride is added in an amount of 50-70% of the sum of the mass of linoleic acid and linolenic acid.