A 3-allyl salicylic hydroxamic acid compound and its preparation and application in metal ore flotation

Abstract

The invention discloses 3-allyl salicylic acid hydroxamic acid compounds and their application in metal ore flotation. In the invention, 3-allyl salicylic acid hydroxamic acid compounds are used as flotation collectors to flotation-recover valuable metal minerals from rare earth, tin, tungsten, titanium, copper, iron and other ores. The flotation collector can effectively improve the flotation enrichment and recovery of rare earth, tin, tungsten, titanium, copper, iron and other minerals, and improve the flotation recovery rate of valuable metal ores.

Description

Technical Field

[0001] The invention relates to the field of metal ore dressing, and in particular to a flotation collector with a completely new structure. Background Art

[0002] Flotation is the main method to recover metal minerals from metal ores. The key to achieving flotation separation between minerals is to selectively regulate the hydrophobicity of the mineral interface by flotation collectors. As metal mineral resources become increasingly poor, fine, and mixed, the difficulty of flotation recovery of metal minerals increases. The development of new and efficient flotation collectors and the improvement of the hydrophobicity of mineral particles are of great significance to improving the comprehensive recovery rate of metal minerals.

[0003] Hydroxamic acid compounds are chelating collectors for metal ores such as cassiterite, rare earth ores, ilmenite, bauxite, tungsten ore, and copper oxide ores. Chinese patent CN108456153A discloses a preparation method of phenylpropenyl hydroxamic acid (structural formula a) and its application in tungsten ore flotation. It is believed that phenylpropenyl hydroxamic acid is an effective flotation collector for wolframite and scheelite (Yu Xinyang, Wang Liping, Hu Linqi, Wang Haolin, Wang Qiangqiang, Huang Zhiqiang, He Guichun. Phenyl hydroxamic acid and its preparation method and application in tungsten ore flotation, CN108456153A, 2018.03.26); Chinese patent CN111285785A discloses a synthesis method of flotation collectors such as amylbenzohydroxamic acid (structural formula b) (Zhao Gang, Zhou Xiaotong, Li Fangxu, Deng Lihong, Lin Rixiao, Fu Guangqin, Shang Xingke, Guan Tong. A synthesis method of a hydroxamic acid collector, CN111285785A, 2020.03.31). Chinese patent CN111841896A discloses a benzoheterocyclic hydroxamic acid collector (structural formula c), its preparation method and application, and found that benzofuran hydroxamic acid has excellent flotation performance for fluorocarbon cerium ore (Chi Ru'an, Xu Caili, Lv Renliang, Ruan Yaoyang, Feng Jian, Wu Xiaoyan, Xue Yongping, Zhou Fang. A benzoheterocyclic hydroxamic acid collector, its preparation method and application, CN111841896A, 2020.08.06).

[0004]

[0005]

[0006] Although existing hydroxamic acid reagents have good performance, their flotation collection capacity or selectivity still needs to be further improved. Summary of the invention

[0007] The purpose of the present invention is to provide a new structure collector - 3-allylsalicylic hydroxamic acid compounds and an application method thereof in metal ore flotation.

[0008] The object of the present invention is achieved in the following manner:

[0009] A 3-allyl salicylic acid hydroxamic acid compound having a structural formula 1:

[0010]

[0011] Where R is H or C1~C 16 M1 and M2 are independently H, Na or K.

[0012] The present invention provides a compound with a completely new structure. Studies have shown that the compound can effectively improve the flotation recovery of metal ores due to the intramolecular synergy of the compound structure.

[0013] In the present invention, the alkyl group may be a straight chain or a branched chain alkyl group.

[0014] Preferably, R is H or a C1-C6 alkyl group; more preferably, it is H or a methyl group.

[0015] Preferably, M1 and M2 are independently H or sodium.

[0016] The 3-allylsalicylic hydroxamic acid compound of the present invention can be obtained by subjecting the compound of formula 2 to a hydroxamic reaction with hydroxylamine;

[0017]

[0018] The R is H or C1~C 16 R1 is an alkyl group of C1 to C6.

[0019] In the present invention, the compound of formula 2, hydroxylamine and a base (sodium or potassium hydroxide) can be subjected to a hydroximation reaction to obtain a target product in which M is Na or K. In order to obtain a product in which M is H, the product of the hydroximation reaction (hydroxamate portion) can be subjected to a conventional acidification treatment.

[0020] In the present invention, the 3-allylsalicylic acid hydroxamic acid compounds as shown in formula (I) can be prepared by reacting the corresponding 3-allylsalicylic acid methyl ester compounds with hydroxylamine, and the yield is usually higher than 98%.

[0021] The present invention also provides an application of 3-allylsalicylic hydroxamic acid compounds, which are used as collectors for flotation of metal ores.

[0022] The present invention has found that the compound of formula 1 has good capture ability and selectivity for metal ores, and can exhibit excellent capture and separation performance when used as a flotation collector.

[0023] The application of the present invention uses the 3-allyl salicylic hydroxamic acid compound with the structure shown in formula (1) as a flotation collector to efficiently recover valuable metal minerals from metal ores.

[0024] In the present invention, the metal ore is at least one of tin ore, rare earth ore, copper oxide ore, tungsten ore, ilmenite ore and the like.

[0025] The basic process of using the 3-allylsalicylic acid hydroxamic acid compound represented by formula (1) as a collector in metal ore flotation is as follows: (a) grinding the ore and then flotation; (b) adding flotation reagents to adjust the slurry during the grinding and / or flotation process, wherein the added reagents contain at least one 3-allylsalicylic acid hydroxamic acid compound; and (c) floating out the useful metal minerals by froth flotation.

[0026] Preferably, the dosage of the 3-allylsalicylic hydroxamic acid compound is 2-2000 g / t, based on the mass of the flotation feed ore.

[0027] In the present invention, during the flotation process, the pH of the pulp is 5-12, and more preferably 6-9.

[0028] The present invention also provides a flotation agent for metal ore, comprising the 3-allylsalicylic hydroxamic acid compound (compound of formula 1).

[0029] The flotation reagents may include other reagents known in the industry, such as a frother. The frother may be a component known in the industry, and the amount of the frother may be adjusted based on existing methods.

[0030] Beneficial Effects

[0031] The present invention provides a new 3-allyl salicylic hydroxamic acid compound, and innovatively proposes the use of the compound as a metal ore flotation collector. Compared with other modified salicylic hydroxamic acid compounds, the preparation process of 3-allyl salicylic hydroxamic acid compounds is simple, economical, efficient, and commercially feasible. Modifying the allyl group at the 3-position of the benzene ring of salicylic hydroxamic acid (salt) helps to improve the hydrophobicity of froth flotation, effectively strengthen the flotation enrichment and recovery of rare earth, tin, tungsten, titanium, copper, iron and other minerals, and improve the flotation recovery rate of valuable metal ores. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 H NMR Spectrum of 3-(2-propenyl)salicylic acid

[0033] Figure 2 UV Spectrum of 3-(2-propenyl)salicylic acid

[0034] Figure 3 Effect of pH on the flotation of cassiterite with 3-(2-propenyl) salicylic acid and salicylic acid DETAILED DESCRIPTION

[0035] The present invention is further illustrated by the following examples, but is not limited to the specific examples. All parts and percentages in the examples are by weight unless otherwise specified.

[0036] Preparation example:

[0037] In methanol solvent, add hydroxylamine hydrochloride (7.76g, 0.11mol), then add sodium hydroxide (8.75g, 0.21mol) in batches, stir for 30min, add 3-(2-propenyl) salicylic acid methyl ester (19.2g, 0.1mol), heat to 55℃, keep warm for 5h, remove the solvent by vacuum distillation, and obtain yellow-brown 3-(2-propenyl) salicylic acid sodium hydroxamate solid, with a yield of 98%. After acidification and purification, the nuclear magnetic resonance hydrogen spectrum of 3-(2-propenyl) salicylic acid sodium hydroxamate is shown in Figure 1 and Table 1, UV spectrum see Figure 2 Other compounds of the same type can be synthesized using this method.

[0038] Table 1 Analysis of H NMR spectrum of 3-(2-propenyl) salicylic acid

[0039]

[0040] Example 1 Flotation performance of cassiterite with 3-(2-propenyl) salicylic acid

[0041] When the concentration of 3-(2-propenyl) salicylic acid was 3×10 -4 mol / L, when the pulp pH is about 8.0, the concentration of the frother (MIBC) is 30mg / L, the N2 gas flow rate is 200mL / min, and the cassiterite with a particle size of -0.076mm to +0.038mm is floated for 3 minutes, at which time the flotation recovery rate of cassiterite reaches 95%. When salicylic acid is used as the collector, under the same conditions, the recovery rate of cassiterite is 7%.

[0042] In addition, compared with 3×10 -4 mol / L 3-(2-propenyl) salicylic acid and 3×10 -4 The flotation performance of cassiterite by 1.5 mol / L salicylic acid at different pH values ​​is shown in the following table. Figure 3 shown. Figure 3 The results show that within the experimental pH range, the capture ability of 3-(2-propenyl) salicylic acid for cassiterite is significantly stronger than that of salicylic acid.

[0043] When the concentration of 3-(2-propenyl) salicylic acid was 1×10 -4mol / L, when the slurry pH is about 8.0, the concentration of the frother (MIBC) is 30 mg / L, the N2 gas flow rate is 200 mL / min, and the cassiterite with a particle size of -0.076 mm to +0.038 mm is floated for 3 minutes. At this time, the flotation recovery rate of cassiterite reaches 67%.

[0044] Example 2 Flotation of bastnaesite with 3-(2-propenyl) salicylic acid

[0045] When the concentration of 3-(2-propenyl) salicylic acid was 3×10 -4 mol / L, the pH of the ore pulp is about 8.0, the concentration of the frother (MIBC) is 30mg / L, the N2 gas flow rate is 200mL / min, and the fluorocarbon cerium ore with a particle size of -0.076mm to +0.038mm is floated for 3 minutes. At this time, the flotation recovery rate of the fluorocarbon cerium ore is 99%. With salicylic hydroxamic acid as the collector, under the same conditions, the flotation recovery rate of the fluorocarbon cerium ore is 73%.

[0046] When the concentration of 3-(2-propenyl) salicylic acid was 1×10 -4 mol / L, the pH of the ore pulp is about 8.0, the concentration of the frother (MIBC) is 30mg / L, the N2 gas flow rate is 200mL / min, and the fluorocarbon cerium ore with a particle size of -0.076mm to +0.038mm is floated for 3 minutes. At this time, the flotation recovery rate of the fluorocarbon cerium ore is 98%. With salicylic hydroxamic acid as the collector, under the same conditions, the flotation recovery rate of the fluorocarbon cerium ore is 47%.

[0047] Example 3 Flotation of Malachite with 3-(2-propenyl) salicylic acid

[0048] When the concentration of 3-(2-propenyl) salicylic acid was 1×10 -4 mol / L, the pH of the ore pulp is about 8.0, the concentration of the frother (MIBC) is 30mg / L, the N2 gas flow rate is 200mL / min, and the malachite with a particle size of -0.076mm to +0.038mm is floated for 3 minutes. At this time, the flotation recovery rate of malachite is 74%. With salicylic hydroxamic acid as the collector, under the same conditions, the flotation recovery rate of malachite is 2%.

[0049] Example 4 Flotation of Scheelite with 3-(2-propenyl) salicylic acid

[0050] When the concentration of 3-(2-propenyl) salicylic acid was 3×10 -4mol / L, the pH of the ore pulp is about 8.0, the concentration of the frother (MIBC) is 30mg / L, the N2 gas flow rate is 200mL / min, and the scheelite with a particle size of -0.076mm to +0.038mm is floated for 3 minutes. At this time, the flotation recovery rate of the scheelite is 91%. Using salicylic hydroxamic acid as the collector, under the same conditions, the flotation recovery rate of the scheelite is 8%.

[0051] Example 5 Flotation of ilmenite with 3-(2-propenyl) salicylic acid

[0052] When the concentration of 3-(2-propenyl) salicylic acid was 1×10 -4 mol / L, the pH of the ore pulp is about 8.0, the concentration of the frother (MIBC) is 30mg / L, the N2 gas flow rate is 200mL / min, and the ilmenite with a particle size of -0.076mm to +0.038mm is floated for 3 minutes. At this time, the flotation recovery rate of the ilmenite is 82%. With salicylic hydroxamic acid as the collector, under the same conditions, the flotation recovery rate of the ilmenite is 12%.

[0053] Example 6 Flotation of fine cassiterite ore

[0054] The cassiterite shaker tailings in Yunnan contain SnO20.38%, and the flotation process is a primary roughing, in which the amount of sodium carbonate is 3000g / t, pH 8.0, the amount of collector is 600g / t, and tributyl phosphate is 8g / t. The flotation results are shown in Table 2. It shows that compared with benzohydroxamic acid and salicylic hydroxamic acid, 3-(2-methyl-2-propenyl) salicylic hydroxamic acid and 3-(2-propenyl) salicylic hydroxamic acid significantly improve the flotation recovery rate of SnO2 in cassiterite shaker tailings.

[0055] Table 2 Comparison results of cassiterite shaking table tailings flotation

[0056]

[0057] It can be seen from Table 2 that the agent described in the present invention has good capture ability and selectivity.

Claims

1. An application of a 3-allylsalicylic hydroxamic acid compound, characterized in that: It is used as a collector for flotation of metal ore; the metal ore is at least one of tin ore, rare earth ore, copper oxide ore, tungsten ore and ilmenite ore; The 3-allyl salicylic acid hydroxamic acid compound has a structural formula 1: Formula 1 Where R is H or C1~C 16 M1 and M2 are independently H, Na or K.

2. The use according to claim 1, characterized in that R is H or a C1~C6 alkyl group.

3. The use according to claim 2, characterized in that R is methyl.

4. The use according to claim 1, characterized in that The M1 and M2 are independently H or Na.

5. The use according to claim 1, characterized in that The 3-allylsalicylic hydroxamic acid compound is obtained by subjecting the compound of formula 2 to a hydroxamic reaction with hydroxylamine; Formula 2 The R is H or C1~C 16 R1 is a C1~C6 alkyl group.

6. The use according to any one of claims 1 to 5, characterized in that: The following steps are involved: Step (1): crushing and slurrying the metal ore to obtain slurry; Step (2): adding a flotation agent to the ore pulp of step (1), performing flotation, and collecting the obtained flotation concentrate and tailings; the flotation agent comprises the 3-allyl salicylic acid hydroxamic acid compound.

7. The use according to any one of claims 1 to 5, characterized in that: Taking the mass of the flotation feed ore as the calculation standard, the dosage of the 3-allylsalicylic hydroxamic acid compound is 2-2000 g / t.

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