Application of ester-based polyamine compounds in mineral flotation

Abstract

This invention belongs to the field of mineral flotation, specifically disclosing an ester-based polyamine compound and its application in mineral flotation. Specifically, the ester-based polyamine compound is used as a flotation collector to efficiently recover silicate or aluminosilicate minerals such as lepidolite, quartz, or mica from ores. Compared to existing aliphatic amine collectors, which suffer from drawbacks such as viscous foam, sensitivity to slime, poor flotation foam flowability, and numerous inclusions, leading to unstable flotation operations, low separation efficiency, and low recovery rates of valuable minerals, the ester-based polyamine compound has advantages such as weak foaming ability, good decoupling properties, and good flotation foam flowability. Furthermore, the hydrophobicity and foaming properties of the ester-based polyamine compound are easily controlled, making it easy to disperse in the pulp and improve the flotation recovery rate of silicate or aluminosilicate minerals such as lepidolite, quartz, feldspar, or mica. In addition, the ester-based polyamine compound is inexpensive and has a wide range of raw material sources.

Description

Technical Field

[0001] This invention relates to the field of mineral flotation, and more specifically to the field of mineral flotation collectors. Background Technology

[0002] Amine compounds are a class of cationic collectors commonly used in mineral flotation. These collectors hydrolyze in water to form -NH4+. 3+ Cationic groups can interact electrostatically with mineral surfaces (Yan Yawen, Luo Huihua, Zhao Jun, et al. Application status and development prospects of amine collectors. Mineral Resources Conservation and Utilization, 202242(02):59-66), effectively adsorbing onto the negatively charged surfaces of silicate or aluminosilicate minerals (MJPearse, An overview of the use of chemical reagents in mineral processing, Minerals Engineering, 18(2005)139-149). Therefore, amine surfactants are commonly used collectors for silicate or aluminosilicate minerals. Dodecylamine, as a classic amine collector, is widely used in the flotation of lepidolite and has good collecting performance for lepidolite (BULATOVIC S M. Handbook offlotation reagents: chemistry, theory and practice: 1st ed[M]. Amsterdam: The Netherland Elsevier, 2007); FILIPPOV et al. used monoether amines as collectors to recover fine-grained lepidolite by flotation (FILIPPOV LO, FILIPPOVAIV, CRUMIERE G, et al. Separation of lepidolite from hard-rock pegmatite ore via dry processing and flotation[J]. Minerals Engineering, 2022, 187: 107768.). However, amine collectors generally suffer from drawbacks in flotation processes, such as sticky foam, large and abundant foam, difficulty in rapid foam coalescence, poor foam flowability, sensitivity to slime, and high levels of inclusions. These drawbacks lead to unstable flotation operations, low separation efficiency, and low recovery rates of valuable minerals. Therefore, developing novel amine surfactants with easily controllable foaming properties and good foam coalescence performance is a research hotspot in the development of amine collectors. Currently, there are no reports in existing technologies regarding the use of ester-based polyamine compounds as flotation reagents. Summary of the Invention

[0003] The purpose of this invention is to provide an ester-based polyamine compound with weak foaming ability as a flotation collector for mineral flotation, aiming to improve the flotation enrichment and recovery efficiency of silicate or aluminosilicate minerals.

[0004] A second objective of this invention is to provide flotation reagents comprising the ester-based polyamine compounds.

[0005] An application of an ester-based polyamine compound in mineral flotation, using it as a collector for mineral flotation collection; wherein the mineral is a silicate mineral containing at least one of silicate and aluminosilicate minerals;

[0006] The ester-based polyamine compounds are free compounds having the structure of Formula 1 and their derived salts;

[0007]

[0008] R1 is C6-C 22 The alkyl group or alkyl group with substituent a; R2 and R3 are individually H or C1-C4 alkyl groups; Y is a carbon chain or a heteroatom-hybridized carbon chain, and the heteroatom is O or N; the carbon chain is allowed to contain substituent b; the substituent a and substituent b are individually at least one of C1-C4 alkyl, C1-C4 alkoxy, halogen, phenyl, and trifluoromethyl.

[0009] This invention innovatively demonstrates that the compound of Formula 1, based on the synergistic effect of its intramolecular structure, can exhibit low foaming properties and excellent targeting and selectivity for silicate minerals, effectively improving the collection ability and selectivity of silicate minerals.

[0010] In this invention, in R1, the alkyl group can be a straight-chain or branched alkyl group. The alkyl group with substituent a can be C1-C2. 20 A substituted alkyl group with a substituent a on its carbon chain. As a typical example, R1 is C8-C9. 20 The straight-chain or branched alkyl group can further be 2-ethylhexyl, dodecyl, tetradecyl, hexadecyl or octadecyl.

[0011] In this invention, as a typical example, R3 is H, and R2 is H, methyl, or ethyl.

[0012] In this invention, Y can be C1-C 10 A carbon chain, or a carbon chain in which the non-terminal carbons are hybridized with heteroatoms such as O or N.

[0013] As a typical example, Y is a C1-C8 alkylene group, or an N-hybridized C2-C8 alkylene group; preferably, Y is...

[0014] The n and m mentioned are integers from 1 to 3.

[0015] In this invention, the ester-based polyamine compound may further be a free compound having at least one structure of Formula 1-A or Formula 1-B, or a salt derived therefrom.

[0016]

[0017]

[0018] In Equations 1-A and 1-B, R1 is C8-C. 16 alkyl group; R2 is H or methyl; n and m are integers from 1 to 2;

[0019] In this invention, the derived salt can be at least one of hydrochloride and sulfate.

[0020] In this invention, the compound of Formula 1 can be a commercial product or prepared based on known methods.

[0021] For example, it can be obtained through reactions of Equations 2 and 3.

[0022]

[0023] In this invention, the mineral is at least one of lepidolite, quartz, or mica.

[0024] The present invention demonstrates that the compound of Formula 1, based on the synergistic combination of its intramolecular structure, exhibits superior compatibility and synergy with the mineral surface and flotation properties of silicate and aluminosilicate minerals, and can significantly improve the targeted collection effect of silicate and aluminosilicate minerals.

[0025] In this invention, apart from using the collector of Formula 1 described herein, there are no special requirements for other flotation equipment and processes. For example, the flotation steps are as follows:

[0026] Step (1): The ore is crushed and mixed to obtain a slurry;

[0027] Step (2): Add flotation reagents containing the ester-based polyamine compounds to the slurry in step (1) for flotation and collect the flotation concentrate.

[0028] In this invention, the weight of the flotation feed ore is used as the calculation standard, and the dosage of the ester-based polyamine compound is 20-2000 g / t.

[0029] Considering processing costs, the concentration of the ester-based polyamine compounds in the flotation pulp can be further increased to 1 × 10⁻⁶.-5 ~1×10 -3 mol / L, and further can be 2×10 -5 ~1.5×10 -4 mol / L.

[0030] In this invention, the pH value of the pulp in the flotation stage is 2.5-11.0, and can be further 3-8.5.

[0031] In this invention, during the flotation process, other flotation aids known in the industry, such as frothers and pH adjusters, can be selectively added as needed.

[0032] In this invention, the ester-based polyamine compounds exhibit excellent compatibility with silicate minerals, demonstrating superior targeting and selectivity. For example, as one possible application, these ester-based polyamine compounds can be used as collectors to selectively collect silicate minerals from minerals containing apatite and silicate minerals (such as silicates and / or aluminosilicates). Research in this invention shows that, in addition to effectively collecting silicate minerals, the ester-based polyamine compounds also possess excellent selective collection of apatite and silicate minerals.

[0033] The present invention also provides a mineral flotation reagent, comprising a collector, wherein the collector comprises the aforementioned ester-based polyamine compound. Furthermore, the flotation reagent may also contain at least one of a frother and a pH adjuster. Preferably, the mineral flotation reagent is for at least one of silicate and aluminosilicate minerals, and more preferably for at least one of lepidolite, quartz, or mica minerals.

[0034] The beneficial effects of this invention are:

[0035] This invention provides a novel application of ester-based polyamine compounds as flotation collectors for silicates, aluminosilicates, particularly lepidolite, quartz, or mica. Research in this invention shows that, based on the intramolecular synergistic linkages and structural segments within the molecules of these ester-based polyamine compounds, they exhibit outstanding characteristics such as weak foaming ability, good decoupling properties, and excellent flotation foam flowability. They are unexpectedly well-suited to the surface properties and flotation behavior of silicate or aluminosilicate minerals such as lepidolite, quartz, or mica, effectively improving the flotation recovery and selectivity of these minerals. Furthermore, ester-based polyamine compounds are inexpensive, have a wide availability of raw materials, and low reagent costs. Attached Figure Description

[0036] Figure 1 The N-(2-aminoethyl)-β-alanine isooctyl ester hydrochloride in Example 2 1HNMR spectrum;

[0037] Figure 2 The N-(2-aminoethyl)-β-alanine isooctyl ester hydrochloride in Example 2 13 C NMR spectrum;

[0038] Figure 3 The flotation results of lepidolite in Example 2;

[0039] Figure 4 The flotation results of lepidolite in Example 3; Detailed Implementation

[0040] This invention provides a novel application of ester-based polyamine compounds as flotation collectors, particularly their application in the flotation collection of at least one mineral, such as silicates, aluminosilicates, lepidolite, quartz, or mica.

[0041] In this invention, as a typical example, the ester-based polyamine compound can be of formula (I);

[0042]

[0043] In equation (Ⅰ), R 1 For C6-C 22 alkyl, R 2 It can be methyl or hydrogen, and n is 0, 1, 2, or 3. The R mentioned above... 1 Preferably, it is 2-ethylhexyl, dodecyl, tetradecyl, hexadecyl, or octadecyl. The R... 2 Hydrogen is preferred, and n is 0 or 1.

[0044] The ester-based polyamine compound having the structure of formula (Ⅰ) was prepared from acrylate and polyamine as raw materials according to the reported method (Changzhou University. An epoxy resin-based intumescent fire retardant coating containing a flexible curing agent and its preparation method: CN202211062007.7[P].2022-11-11).

[0045] The following examples are intended to further illustrate the invention, but not to limit the scope of protection of the invention. All parts and percentages in the examples refer to mass unless otherwise specified. The flotation processes for the minerals in the examples are conventional processes, except that the ester-based polyamine compounds of the present invention are used instead of conventional flotation collectors.

[0046] For example, the steps of using the flotation collector for flotation include:

[0047] Step (1): The ore is crushed and mixed to obtain a slurry;

[0048] Step (2): Add flotation reagents to the slurry from step (1) for flotation and collect the flotation concentrate; the flotation reagents include the ester-based polyamine compounds.

[0049] In this invention, the amount of collector and flotation conditions can be adjusted according to the mineral conditions and flotation requirements. For example, based on the weight of the feed ore, the dosage of the ester-based polyamine compound is 20-2000 g / t, and the pH of the pulp is 2.5-11.0.

[0050] The following are typical examples, for instance:

[0051] Example 1: Foaming performance test of N-(2-aminoethyl)-β-alanine dodecyl ester and N-[2-[(2-aminoethyl)amino]ethyl]-β-alanine dodecyl ester

[0052] The collector concentration is 1×10 -4 The frothing performance of the flotation system was investigated using 1 or 2 grams of lepidolite or quartz with a solution volume of 220 ml and a particle size of -0.076 to +0.038 mm. The maximum height of the foam reached during aeration (foam layer height) and the time required for the foam to completely disappear after the aeration valve was closed (defoaming time) were used as indicators. The effects of pH, nitrogen flow rate, and the amount of lepidolite or quartz on the foaming performance of the flotation system were examined. The results are shown in Table 1. The experimental results in Table 1 show that, compared with the conventional amine collector dodecylamine, ester-based polyamine compounds such as N-(2-aminoethyl)-β-alanine dodecyl ester and N-[2-[(2-aminoethyl)amino]ethyl]-β-alanine dodecyl ester produced significantly lower foam heights and shorter defoaming times under the same conditions. This indicates that ester-based polyamine compounds have weak foaming ability and good coagulation properties when flotating silicate or aluminosilicate minerals such as lepidolite and quartz.

[0053] Table 1. Test conditions and results for the foaming properties of ester-based polyamine compounds.

[0054]

[0055] Example 2: Flotation of lithium mica using N-(2-aminoethyl)-β-alanine isooctyl ester salt

[0056] The NMR spectra of N-(2-aminoethyl)-β-alanine isooctyl ester hydrochloride are shown below. Figure 1 and Figure 2 .

[0057] At a pulp pH of 3 and an N2 gas flow rate of 200 ml / min, lepidolite with a particle size of -0.076 to +0.038 mm was floated for 6 minutes. The flotation results are shown in the figure. Figure 3 The results showed that the optimal dosage of N-(2-aminoethyl)-β-alanine isooctyl ester was 1×10⁻⁶.-4 At a concentration of mol / L, the recovery rate of lepidolite reached 94.56%. Under the same conditions, using 1×10⁻⁶ mol / L... -4 Using isooctylamine at a concentration of mol / L as the collector, the recovery rate of lepidolite was only 60.59%. This indicates that N-(2-aminoethyl)-β-alanine isooctyl ester has a significantly stronger collecting ability for lepidolite compared to isooctylamine.

[0058] Example 3: Flotation of N-[2-[(2-aminoethyl)amino]ethyl]-β-alanine dodecyl ester with lithium mica

[0059] With a pulp pH of 8, a frother concentration of methyl isobutyl methanol (MIBC) of 15 mg / L, and an N2 gas flow rate of 200 ml / min, lepidolite with a particle size of -0.076 to 0.038 mm was floated for 6 minutes. The flotation results are shown in the figure. Figure 4 The results showed that the optimal dosage of N-[2-[(2-aminoethyl)amino]ethyl]-β-alanine dodecyl ester was 6 × 10⁻⁶. -5 At a concentration of mol / L, the recovery rate of lepidolite reached 98.83%. Under the same conditions, using 6×10 mol / L... -5 Using mol / L dodecylamine as the collector, the recovery rate of lepidolite was only 82.72%. This indicates that N-[2-[(2-aminoethyl)amino]ethyl]-β-alanine dodecyl ester has a significantly stronger collecting ability for lepidolite compared to dodecylamine.

[0060] Example 4: Flotation of quartz with N-(2-aminoethyl)-β-alanine isooctyl ester

[0061] The dosage of N-(2-aminoethyl)-β-alanine isooctyl ester was 8 × 10⁻⁶. -5 At a concentration of mol / L, pulp pH = 3, and N2 gas flow rate of 200 ml / min, the flotation recovery rate of quartz with a particle size of -0.076 to +0.038 mm was 97.04% after 6 minutes. Under the same conditions, the recovery rate of quartz by isooctylamine flotation was only 38.51%. This indicates that N-(2-aminoethyl)-β-alanine isooctyl ester has a significantly stronger collecting ability for quartz than isooctylamine.

[0062] Example 5: Flotation of quartz with N-[2-[(2-aminoethyl)amino]ethyl]-β-alanine dodecyl ester

[0063] The dosage of N-[2-[(2-aminoethyl)amino]ethyl]-β-alanine dodecyl ester was 4 × 10⁻⁶. -5Under conditions of mol / L mol / L, pulp pH = 8, frother methyl isobutyl methanol (MIBC) concentration of 15 mg / L, and N2 gas flow rate of 200 ml / min, the flotation recovery rate of quartz with a particle size of -0.076 to +0.038 mm was 97.13% after 6 minutes. Under the same conditions, the recovery rate of quartz by dodecylamine flotation was 86.28%. This indicates that N-[2-[(2-aminoethyl)amino]ethyl]-β-alanine dodecyl ester has a significantly stronger collecting ability for quartz than dodecylamine.

[0064] Example 6: Flotation separation of apatite and quartz using N-[2-[(2-aminoethyl)amino]ethyl]-β-alanine dodecyl ester

[0065] The dosage of N-[2-[(2-aminoethyl)amino]ethyl]-β-alanine dodecyl ester was 3 × 10⁻⁶. -5 Under the conditions of mol / L, pulp pH = 8.5, frother methyl isobutyl methanol (MIBC) concentration of 12 mg / L, and N2 gas flow rate of 200 ml / min, a mixed ore (apatite:quartz = 1:1, w / w) with a particle size of -0.076 to +0.038 mm was floated for 5 minutes. The quartz recovery rate in the flotation concentrate was 87.25%, and the apatite recovery rate was 18.33%. Under the same conditions, the quartz recovery rate in the flotation concentrate obtained from dodecylamine was 76.34%, and the apatite recovery rate was 30.67%. This indicates that N-[2-[(2-aminoethyl)amino]ethyl]-β-alanine dodecyl ester has significantly higher quartz collection capacity and selectivity than dodecylamine when used for flotation separation of apatite and quartz.

[0066] Therefore, compared with conventional amine collectors, ester-based polyamine compounds not only exhibit weaker foaming ability and better decoupling properties when flotating silicate or aluminosilicate minerals such as lepidolite and quartz, but also improve the flotation recovery rate of lepidolite and quartz. Furthermore, the long carbon chain hydrophobic groups of ester-based polyamine compounds are derived from fatty alcohols, making them widely available and inexpensive. This allows for easy control of the hydrophobicity and foaming properties of ester-based polyamine compounds, further facilitating their industrial applications.

Claims

1. The application of an ester-based polyamine compound in mineral flotation, characterized in that, It is used as a collector for the flotation collection of minerals; the minerals are silicate minerals containing at least one of silicate and aluminosilicate minerals. The ester-based polyamine compounds are free compounds having the structure of Formula 1 and their derived salts; Formula 1 R1 is C6-C 22 The alkyl group or alkyl group with substituent a; R2 and R3 are individually H or C1-C4 alkyl groups; Y is a carbon chain or a heteroatom-hybridized carbon chain, and the heteroatom is O or N; the carbon chain is allowed to contain substituent b; the substituent a and substituent b are individually at least one of C1-C4 alkyl, C1-C4 alkoxy, halogen, phenyl, and trifluoromethyl.

2. The application as described in claim 1, characterized in that, R1 is C8-C 20 Straight-chain or branched alkyl groups.

3. The application as described in claim 2, characterized in that, R1 is 2-ethylhexyl, dodecyl, tetradecyl, hexadecyl, or octadecyl.

4. The application as described in claim 1, characterized in that, R3 is H, and R2 is H, methyl, or ethyl.

5. The application as described in claim 1, characterized in that, The Y is a C1-C8 alkylene group or an N-hybridized C2-C8 alkylene group.

6. The application as described in claim 5, characterized in that, The Y mentioned is or The n and m mentioned are integers from 1 to 3.

7. The application as described in claim 1, characterized in that, The ester-based polyamine compounds are free compounds having at least one structure of Formula 1-A or Formula 1-B, and their derived salts; Formula 1-A Formula 1-B In Equations 1-A and 1-B, R1 is C8-C. 16 The alkyl group; R2 is H or methyl; n and m are integers from 1 to 2.

8. The application as described in claim 7, characterized in that, The derived salt is at least one of hydrochloride and sulfate.

9. The application as described in claim 1, characterized in that, The mineral in question is mica.

10. The application as described in claim 1, characterized in that, The mineral in question is at least one of lepidolite or quartz.

11. The application as described in any one of claims 1 to 10, characterized in that, The steps are as follows: Step (1): The mineral is crushed and mixed to obtain a slurry; Step (2): Add flotation reagents containing the ester-based polyamine compounds to the slurry in step (1) for flotation and collect the flotation concentrate.

12. The application as described in claim 11, characterized in that, The dosage of the ester-based polyamine compound is 20-2000 g / t, calculated based on the weight of the ore fed to the flotation.

13. The application as described in claim 11, characterized in that, The pH value of the pulp during the flotation stage is 2.5-11.0.

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