Preparation and application of apatite combination inhibitor

Abstract

The application discloses a preparation and application of an apatite combined depressant and belongs to the field of ore separation. The combined depressant comprises L-malic acid, hypochlorous acid and sulfuric acid, wherein the mass ratio of the L-malic acid, the hypochlorous acid and the sulfuric acid with a concentration of 10% is 1:(1-5):(2:4). The combined depressant is used in one roughing, one scavenging and one reselection, the combined depressant is used in an amount of 10-13 kg / t in roughing, the combined depressant is used in an amount of 1 kg / t in the scavenging process, and the combined depressant is used in an amount of 2-3 kg / t in the reselection process. Compared with the single use of the sulfuric acid, the combined depressant can reduce the sulfuric acid, the amount of the combined depressant is reduced by 50%-70%, the pH of the ore pulp is between 5 and 6, the combined depressant can inhibit the apatite and relieve the calcium precipitation phenomenon of calcium sulfate in the flotation system, and the combined depressant is a high-efficiency and excellent apatite depressant.

Description

Technical Field

[0001] This invention relates to the preparation and application of an apatite composite inhibitor, belonging to the field of ore beneficiation. Background Technology

[0002] Reverse flotation is commonly used in the beneficiation of phosphate rock to separate carbonates such as apatite and dolomite. Phosphoric acid can be used as a depressant for phosphate rock, but its price is much higher than that of sulfuric acid, so it is not used on a large scale. Currently, sulfuric acid is the most commonly used depressant. Sulfuric acid inhibits apatite, allowing fatty acid flotation of dolomite under acidic conditions. The amount of sulfuric acid depressant used is very large, generally >10 kg / t. Moreover, the addition of sulfuric acid can produce calcium sulfate precipitate that clogs pipes and affects process stability. Therefore, enterprises urgently need highly efficient depressants. Summary of the Invention

[0003] To address the problems existing in the prior art, one objective of this invention is to provide a method for preparing a combined inhibitor of apatite, wherein the combined inhibitor comprises L-malic acid, hypochlorous acid, and sulfuric acid, wherein the mass ratio of L-malic acid, hypochlorous acid, and sulfuric acid is 1:(1-5):(2:4). The specific preparation steps are as follows:

[0004] (1) React L-malic acid and hypochlorous acid at 50-70℃, using vanadium pentoxide (V2O5) as a catalyst (the amount of vanadium pentoxide as a catalyst is not particularly required), and complete the reaction in 30-60 minutes;

[0005] (2) Add 10% sulfuric acid to the solution obtained in step (1) and mix well to obtain a combined inhibitor.

[0006] Another object of the present invention is to provide an application of a combined inhibitor in the flotation of apatite.

[0007] Preferably, apatite is obtained by adding a combination of inhibitors to phosphate rock and then performing reverse flotation through a process of roughing, scavenging, and re-selection.

[0008] Preferably, the dosage of the combined inhibitor in the coarse selection is 10-13 kg / t, the dosage of the combined inhibitor in the scavenging process is 1 kg / t, and the dosage of the combined inhibitor in the reselection process is 2-3 kg / t.

[0009] The principle of this invention: This invention uses L-malic acid (C4H6O5) as a raw material and vanadium pentoxide as a catalyst to react with hypochlorous acid at 50-70℃, oxidizing the OH group in L-malic acid to an aldehyde group, yielding the reaction product 2-aldehyde-succinic acid. The reaction equation is as follows:

[0010]

[0011] The COOH group in 2-aldehyde-succinic acid can react with Ca on the surface of apatite. At the same time, the oxygen in the C=O group of the aldehyde group can also react with Ca on the surface of apatite. L-malic acid cannot inhibit apatite, so the interaction between 2-aldehyde-succinic acid and the surface of apatite has an inhibitory effect. When 2-aldehyde-succinic acid and sulfuric acid are mixed, sulfuric acid can react with the surface of apatite to form calcium sulfate components, while 2-aldehyde-succinic acid can continue to react with multiple calcium atoms on the surface, further preventing the adsorption of the collector on the surface of apatite, thereby reducing the amount of sulfuric acid used.

[0012] Beneficial effects of the present invention

[0013] (1) Using a mixture of 2-aldehyde-succinic acid, the product of the reaction between L-malic acid and hypochlorous acid, and sulfuric acid can significantly reduce the amount of inhibitor used, produce a significant inhibitory effect on apatite, and do not affect the floatability of dolomite, thereby achieving efficient separation of apatite and dolomite from collophane.

[0014] (2) Due to the reduced amount of sulfuric acid inhibitor, the pH of the slurry is between 6 and 6.5, and a large amount of calcium sulfate will not be produced in the slurry, thus preventing the blockage of the pipeline. Detailed Implementation

[0015] The present invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are only for explaining the present invention, but the scope of protection of the present invention is not limited to the content described herein.

[0016] The modified ore samples used in all embodiments were selected from a phosphate mining company in Yunnan Province. The original ore sample had a P2O5 grade of 20.53%, an MgO grade of 6.56%, a SiO2 grade of 15.08%, a CaO grade of 36.33%, and an Al2O3 grade of 1.19%. The main useful mineral in the ore sample was collophane, and the gangue minerals included dolomite, quartz, and feldspar.

[0017] The collectors used in the examples were all YP6-6 mixed fatty acid collectors. The dosage of the reagents in each example is shown in Table 1. All examples were obtained by separating apatite through reverse flotation process.

[0018] Table 1. Dosage of the drug in each example.

[0019]

[0020]

[0021] Example 1

[0022] In this embodiment, the mass ratio of L-malic acid, hypochlorous acid, and sulfuric acid in the combined inhibitor is 1:2:2. The combined inhibitor is prepared as follows:

[0023] (1) L-malic acid and hypochlorous acid were reacted at 60°C using vanadium pentoxide as a catalyst, and the reaction was completed in 45 minutes.

[0024] (2) Add 10% sulfuric acid to the solution obtained in step (1) and mix well to obtain a combined inhibitor.

[0025] The reverse flotation process of the ore adopts a process of roughing and scavenging, followed by regrinding of the scavenged ore and then a final flotation. The reagents and dosages for each step are shown in Table 1. The final concentrate yield of the bottom product is 69.65% apatite, with a P2O5 grade of 29.59%, an MgO grade of 0.77%, and a P2O5 recovery rate of 93.11%.

[0026] Example 2

[0027] In this embodiment, the mass ratio of L-malic acid, hypochlorous acid, and sulfuric acid in the combined inhibitor is 1:2:3. The combined inhibitor is prepared as follows:

[0028] (1) L-malic acid and hypochlorous acid were reacted at 50°C using vanadium pentoxide as a catalyst, and the reaction was completed in 30 minutes.

[0029] (2) Add 10% sulfuric acid to the solution obtained in step (1) and mix well to obtain a combined inhibitor.

[0030] The reverse flotation process of the ore adopts a process of roughing and scavenging, followed by regrinding of the scavenged ore and then a final flotation. The reagents and dosages for each step are shown in Table 1. The final concentrate yield of the bottom product is 66.12% apatite, with a P2O5 grade of 29.38%, an MgO grade of 0.88%, and a P2O5 recovery rate of 91.23%.

[0031] Example 3

[0032] In this embodiment, the mass ratio of L-malic acid, hypochlorous acid, and sulfuric acid in the combined inhibitor is 1:2:4. The combined inhibitor is prepared as follows:

[0033] (1) L-malic acid and hypochlorous acid were reacted at 70°C using vanadium pentoxide as a catalyst, and the reaction was completed in 60 minutes.

[0034] (2) Add 10% sulfuric acid to the solution obtained in step (1) and mix well to obtain a combined inhibitor.

[0035] The reverse flotation process of the ore adopts a process of roughing and scavenging, followed by regrinding of the scavenged ore and then a final flotation. The reagents and dosages for each step are shown in Table 1. The final concentrate yield of the bottom product is 65.15% apatite, with a P2O5 grade of 29.33%, an MgO grade of 0.90%, and a P2O5 recovery rate of 90.11%.

[0036] Example 4

[0037] In this embodiment, the mass ratio of L-malic acid, hypochlorous acid, and sulfuric acid in the combined inhibitor is 1:3:2. The combined inhibitor is prepared as follows:

[0038] (1) L-malic acid and hypochlorous acid were reacted at 60°C using vanadium pentoxide as a catalyst, and the reaction was completed in 45 minutes.

[0039] (2) Add 10% sulfuric acid to the solution obtained in step (1) and mix well to obtain a combined inhibitor.

[0040] The reverse flotation process of the ore adopts a process of roughing and scavenging, followed by regrinding of the scavenged ore and a final re-selection. The reagents and dosages for each step are shown in Table 1. The final concentrate indicators are: apatite yield of 66.16%, P2O5 grade of 29.23%, MgO grade of 0.84%, and P2O5 recovery rate of 91.46%.

[0041] Example 5

[0042] In this embodiment, the mass ratio of L-malic acid, hypochlorous acid, and sulfuric acid in the combined inhibitor is 1:4:3. The combined inhibitor is prepared as follows:

[0043] (1) L-malic acid and hypochlorous acid were reacted at 60°C using vanadium pentoxide as a catalyst, and the reaction was completed in 45 minutes.

[0044] (2) Add 10% sulfuric acid to the solution obtained in step (1) and mix well to obtain a combined inhibitor.

[0045] The reverse flotation process of the ore adopts a process of roughing and scavenging, followed by regrinding of the scavenged ore and then a final flotation. The reagents and dosages for each step are shown in Table 1. The final concentrate yield of the bottom product is 66.87% apatite, with a P2O5 grade of 29.25%, an MgO grade of 0.81%, and a P2O5 recovery rate of 91.22%.

[0046] Example 6

[0047] In this embodiment, the mass ratio of L-malic acid, hypochlorous acid, and sulfuric acid in the combined inhibitor is 1:5:4. The combined inhibitor is prepared as follows:

[0048] (1) L-malic acid and hypochlorous acid were reacted at 60°C using vanadium pentoxide as a catalyst, and the reaction was completed in 45 minutes.

[0049] (2) Add 10% sulfuric acid to the solution obtained in step (1) and mix well to obtain a combined inhibitor.

[0050] The reverse flotation process of the ore adopts a process of roughing and scavenging, followed by regrinding of the scavenged ore and a final re-selection. The reagents and dosages for each step are shown in Table 1. The final concentrate yield of the bottom product is 64.32% apatite, with a P2O5 grade of 29.30%, an MgO grade of 0.85%, and a P2O5 recovery rate of 91.01%.

[0051] Comparative Example 1

[0052] For comparison, this example differs from Example 1 in that the inhibitor used is only sulfuric acid, while the process flow is the same as in Example 1, and the dosage of reagents in each step is shown in Table 1. A process flow of one roughing and one scavenging step, followed by regrinding of the scavenged ore and one final beneficiation step was adopted. The final concentrate yield was 62.41%, with a P2O5 grade of 29.19%, an MgO grade of 0.95%, and a P2O5 recovery rate of 89.60%.

[0053] By comparing the results of Example 1 and Comparative Example 1, it was found that the yield of apatite in Example 1 was 7.24% higher than that in Comparative Example 1, the P2O5 grade was 0.4% higher than that in Comparative Example 1, the MgO grade was 0.18% lower than that in Comparative Example 1, and the P2O5 recovery rate was 3.51% higher than that in Comparative Example 1. In addition, the amount of reagent used in Example 1 was less than that in Comparative Example 1. Therefore, it can be seen that the reverse flotation effect of the combined inhibitor in Example 1 is better than that of Comparative Example 1 which only used sulfuric acid as an inhibitor.

Claims

1. A method for preparing an apatite combination inhibitor, characterized in that: The combined inhibitor comprises L-malic acid, hypochlorous acid, and 10% sulfuric acid, wherein the mass ratio of L-malic acid, hypochlorous acid, and 10% sulfuric acid is 1:(1-5):(2:4). The specific preparation steps are as follows: (1) React L-malic acid and hypochlorous acid at 50-70℃, using vanadium pentoxide as a catalyst, and complete the reaction in 30-60 minutes; (2) Add 10% sulfuric acid to the solution obtained in step (1) and mix well to obtain a combined inhibitor.

2. The application of the combined inhibitor of claim 1 in the flotation of apatite.

3. The application of the combined inhibitor according to claim 2 in the flotation of apatite, characterized in that: Apatite was obtained by adding a combination of inhibitors to collophane and then performing reverse flotation through a process of roughing, scavenging, and re-selection.

4. The application of the combined inhibitor according to claim 3 in the flotation of apatite, characterized in that: The dosage of combined inhibitor in the roughing process is 10-13 kg / t, the dosage of combined inhibitor in the scavenging process is 1 kg / t, and the dosage of combined inhibitor in the re-selection process is 2-3 kg / t.

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