Spodumene flotation reagent and preparation method thereof

Abstract

The invention relates to the technical field of flotation, and discloses a spodumene flotation reagent and a preparation method thereof, and the spodumene flotation reagent comprises sulfonated oleic acid, phosphonic acid modified oleic acid hydroximic acid, peroxyoleic acid soap, fatty acid polyoxyethylene ether, polyether amine and an alcohol compound. According to the flotation reagent provided by the invention, the phosphonic acid modified oleic hydroximic acid is introduced, so that the phosphonic acid modified oleic hydroximic acid and spodumene can form a stable chelate on the basis of retaining the collecting property of carboxylic acid groups, and the problem of poor selectivity caused by single addition of oleic acid can be avoided; and by introducing sulfonated oleic acid, fatty acid polyoxyethylene ether and polyether amine, the collecting capacity of metal ions on the surface of spodumene can be enhanced, and flotation is facilitated.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of flotation, in particular to a spodumene flotation reagent and a preparation method thereof. BACKGROUND

[0002] Spodumene is a lithium-containing silicate mineral belonging to the hexagonal system, and its chemical formula is LiAlSi2O6. It is often formed in pegmatite deposits and is an important mineral resource with wide industrial applications. At present, the main methods for spodumene beneficiation include flotation, hand sorting, thermal cracking, heavy medium separation, magnetic separation, and combined beneficiation, among which flotation is the most widely used method in spodumene beneficiation.

[0003] The difficulty of spodumene flotation lies in the flotation separation of various silicate minerals and other minerals with similar floatability, such as hornblende, beryl, quartz, feldspar, mica, garnet, and apatite. Commonly used collectors in the spodumene flotation industry include fatty acids and their soaps (731, naphthenic acid soap, oleic acid, and tall oil), amine cationic collectors, and alkyl sulfate and sulfonate. The above collectors have obvious defects, such as fatty acid collectors, which not only require a large amount of use, but also have poor collection effect when used alone and need to be combined with multiple collectors. In addition, they are sensitive to temperature, difficult to dissolve and disperse, and require harsh conditions for use. Alkyl sulfate and alkyl sulfonate collectors require an acidic environment to effectively separate spodumene, and the flotation equipment needs to have corrosion resistance. Although amine collectors have strong collection ability for spodumene, they also have strong collection ability for other silicate gangue minerals, resulting in poor selectivity. SUMMARY

[0004] The technical problem solved by the present application is:

[0005] To solve the problems of poor temperature resistance and poor selectivity in the existing spodumene flotation.

[0006] The technical solution adopted by the present application is:

[0007] In view of the above technical problems, the present application aims to provide a spodumene flotation reagent and a preparation method thereof.

[0008] Based on this, the specific implementation is:

[0009] Firstly, the present application provides a spodumene flotation reagent, which comprises sulfonated oleic acid, phosphonic acid modified oleic acid hydroxamic acid, peroxide oleic acid soap, fatty acid polyoxyethylene ether, polyether amine, and alcohol compounds.

[0010] According to some preferred embodiments, the raw materials are composed of 10-30 parts of sulfonated oleic acid, 10-30 parts of phosphonic acid modified oleic hydroxamic acid, 2-8 parts of peroxide oleic acid soap, 5-15 parts of fatty acid polyoxyethylene ether, 10-25 parts of polyether amine, and 5-15 parts of alcohol compound.

[0011] According to some preferred embodiments, the preparation method of the phosphonic acid modified oleic hydroxamic acid is as follows:

[0012] In the first step, oleic acid is blended with methanol, H2SO4 is used as the catalyst, and the mixture is refluxed at 60-80℃ for 2-6h. After the reaction, the mixture is washed with saturated sodium carbonate solution until it is neutral, and then the methyl oleate is obtained by vacuum distillation. The mass ratio of oleic acid, methanol and concentrated sulfuric acid is 100:30:2.

[0013] In the second step, hydroxylamine hydrochloride is dissolved in water, and then NaOH is added dropwise to adjust the pH to 10. Then, methyl oleate is added, and the mixture is reacted at 65-85℃ for 4-8h. After the reaction, the mixture is acidified with hydrochloric acid until the pH is 2, and then the solid is precipitated. The oleic hydroxamic acid is obtained by filtration and recrystallization with ethanol. The mass ratio of hydroxylamine hydrochloride and methyl oleate is 28:80.

[0014] In the third step, the oleic hydroxamic acid and diethyl phosphite are dissolved in toluene, and then triethylamine is added. The mixture is reacted at 70-90℃ for 6-12h. After the reaction, the intermediate is obtained by removing the solvent by vacuum distillation. The mass ratio of oleic hydroxamic acid, diethyl phosphite, triethylamine and toluene is 50:30:20:200. Then, the intermediate is dissolved in a solvent (THF and H2O in a volume ratio of 3:1), and 37% concentrated hydrochloric acid is added. The mixture is hydrolyzed at 45-70℃ for 10-15h, and then the solid is precipitated. The phosphonic acid modified oleic hydroxamic acid is obtained by filtration, water washing and drying. The mass ratio of the intermediate, the solvent and the concentrated hydrochloric acid is 1:10:0.7.

[0015] According to some preferred embodiments, the polyether amine is polyether amine D230.

[0016] According to some preferred embodiments, the alcohol compound includes at least one of methanol, ethanol and n-butanol.

[0017] Secondly, the present application provides a preparation method of the lithium feldspar flotation reagent mentioned above. The sulfonated oleic acid, the phosphonic acid modified oleic hydroxamic acid, the peroxide oleic acid soap, the fatty acid polyoxyethylene ether, the polyether amine and the alcohol compound are blended in proportion to obtain the flotation reagent.

[0018] Thirdly, the present application provides a lithium feldspar flotation method, which uses the flotation reagent mentioned above to float the lithium feldspar ore.

[0019] According to some preferred embodiments, the spodumene raw ore is ground to obtain a slurry; a pH adjusting agent, an inhibitor, an activator and a flotation reagent are added to the slurry to obtain a rough concentrate and a rough tailing through roughing; a pH adjusting agent and a flotation reagent are added to the rough tailing to obtain a tailing through two times of scavenging; a pH adjusting agent and a flotation reagent are added to the rough concentrate to obtain a lithium concentrate through three times of cleaning; and the middlings obtained in the scavenging and cleaning are sequentially returned to the previous stage.

[0020] According to some preferred embodiments, the pH adjusting agent comprises at least one of sodium carbonate and sodium hydroxide.

[0021] According to some preferred embodiments, the inhibitor comprises at least one of water glass and carboxymethyl cellulose.

[0022] According to some preferred embodiments, the activator comprises calcium chloride.

[0023] According to some preferred embodiments, the water glass is modified by silane to form an organic-inorganic hybrid inhibitor, so as to improve the dense coverage of associated minerals. Specifically,

[0024] 10wt% of water glass is adjusted to a pH value of 8-9 to obtain a water glass solution;

[0025] Methyl triethoxysilane, water and ethanol are blended at a volume ratio of 1:8:10, 10% of 0.1mol / L hydrochloric acid solution is added, and the mixture is treated at 35-50℃ for 20-60min to obtain a silane solution;

[0026] Ammonia water and ethanol are blended at a volume ratio of 3-5:1, the ammonia water has a concentration of 0.5mol / L, the temperature is kept at 50℃, the water glass solution and the silane solution are sequentially added, the mass ratio of the ammonia water, the water glass solution and the silane solution is 1:2:0.5-1, and the mixture is stirred at a constant temperature of 40-55℃ for 60-90min, and then aged, centrifuged, filtered and dried to obtain the modified water glass.

[0027] The technical mechanism and beneficial effects of the present application are as follows:

[0028] (1) The flotation reagent provided by the present application obtains phosphonic acid modified hydroxamic acid from oleic acid, introduces hydroxamoyl into the oleic acid, so that it can act on the surface of spodumene through strong chelation, thereby providing stable adsorption sites for the oleic acid; and the long carbon chain in the oleic acid enhances the hydrophobicity of the surface of the spodumene; at the same time, the introduction of hydroxamoyl into the oleic acid can form a stable chelate with the spodumene on the basis of retaining the collecting property of the carboxylic acid group, thereby avoiding the poor selectivity caused by the addition of oleic acid alone; and the introduction of phosphonic acid group further improves the coordination ability with Li + in the spodumene, thereby improving the selectivity for Li + .

[0029] (2) The flotation reagent provided by the present application is prepared by compounding phosphonic acid modified oleic hydroxamic acid with sulfonated oleic acid, using the electrostatic repulsion of the sulfonated oleic acid to reduce the adsorption on gangue minerals, and using the sulfonated oleic acid to optimize the dispersibility of the ore slurry, thereby reducing the interference of slimes. The peroxycarboxyl group in the peroxo oleic acid soap and the hydroxamic acid functional group form a bifunctional group, so that they act on Li + and Al 3+ respectively, thereby enhancing the collecting ability on the minerals and facilitating flotation.

[0030] (3) The flotation reagent provided by the present application is prepared by introducing a fatty alcohol polyoxyethylene ether, using the strong hydrophilicity of the fatty alcohol polyoxyethylene ether to wrap the phosphonic acid modified oleic hydroxamic acid and the sulfonated oleic acid, thereby forming micelles, and further improving the water solubility and low-temperature fluidity of the flotation reagent. The hydrophobic chain in the fatty alcohol polyoxyethylene ether is associated with the alkyl chain of the collector, thereby achieving the purpose of enhancing the adsorption compactness.

[0031] (4) The flotation reagent provided by the present application is prepared by introducing a polyether amine. The amino group in the polyether amine can coordinate with Al 3+ on the surface of spodumene, and the polyether amine can hydrophobically associate with the oleic hydroxamic acid, thereby reducing the problem of slow adsorption at low temperatures. The long-chain polyether in the polyether amine forms a steric hindrance layer, thereby achieving the purpose of synergistically inhibiting gangue minerals. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical scheme and advantages of the embodiments of the present application more clear, the technical scheme in the embodiments of the present application will be clearly and completely described below. If the specific conditions are not specified in the embodiments, the conventional conditions or the conditions recommended by the manufacturer are used. If the reagents or instruments used are not specified by the manufacturer, they are all conventional products that can be purchased on the market.

[0033] Embodiment 1

[0034] The present embodiment provides a spodumene flotation reagent. The components are as follows in terms of weight fraction: 25 parts of sulfonated oleic acid, 25 parts of phosphonic acid modified oleic hydroxamic acid, 5 parts of peroxo acetic acid soap, 10 parts of fatty acid polyoxyethylene ether, 20 parts of polyether amine D230, and 10 parts of ethanol.

[0035] In the foregoing, the preparation method of the phosphonic acid modified oleic hydroxamic acid is as follows:

[0036] Firstly, oleic acid is blended with methanol, H2SO4 is used as a catalyst, and the mixture is refluxed at 75℃ for 4h. After the reaction is completed, the mixture is washed with saturated sodium carbonate solution until it is neutral. The oil methyl ester is obtained by reduced pressure distillation. The mass ratio of oleic acid, methanol and concentrated sulfuric acid is 100:30:2.

[0037] Second step, hydroxylamine hydrochloride forms an aqueous solution, and then drop NaOH to adjust pH = 10, then add methyl oleate, react at 70℃ for 6h, then acidified with hydrochloric acid to pH = 2, precipitate solid, filter, recrystallize with ethanol to obtain hydroxamic acid of oleic acid; the mass ratio of hydroxylamine hydrochloride and methyl oleate is 28:80.

[0038] Third step, hydroxamic acid of oleic acid is dissolved in diethyl phosphite in toluene, then add triethylamine, react at 85℃ for 10h, after the reaction, remove the solvent under reduced pressure to obtain the intermediate, the mass ratio of hydroxamic acid of oleic acid, diethyl phosphite, triethylamine, toluene is 50:30:20:200; dissolve the intermediate in solvent (THF and H2O volume ratio is 3:1), then add 37% concentrated hydrochloric acid, hydrolyze at 60℃ for 12h, precipitate solid, filter, wash with water, dry to obtain phosphonic acid modified hydroxamic acid of oleic acid; the mass ratio of intermediate, solvent, concentrated hydrochloric acid is 1:10:0.7.

[0039] The preparation method of the lithium aluminosilicate flotation reagent is that the sulfonated oleic acid, the phosphonic acid modified hydroxamic acid of oleic acid, the peroxyl oleic acid soap, the fatty acid polyoxyethylene ether, the polyether amine D230 and the ethanol are blended in proportion to obtain the flotation reagent.

[0040] Example 2

[0041] The difference between the example and the example 1 is that the sulfonated oleic acid is 20 parts, the phosphonic acid modified hydroxamic acid of oleic acid is 20 parts, the peroxyl oleic acid soap is 5 parts, the fatty acid polyoxyethylene ether is 12 parts, the polyether amine D230 is 15 parts and the ethanol is 12 parts.

[0042] Comparative example 1

[0043] The difference between the comparative example and the example 1 is that the phosphonic acid modified hydroxamic acid of oleic acid is not added.

[0044] Comparative example 2

[0045] The difference between the comparative example and the example 1 is that the phosphonic acid modified hydroxamic acid of oleic acid is replaced by hydroxamic acid of oleic acid.

[0046] Comparative example 3

[0047] The difference between the comparative example and the example 1 is that the phosphonic acid modified hydroxamic acid of oleic acid is replaced by benzylic hydroxamic acid.

[0048] Comparative example 4

[0049] The difference between the comparative example and the example 1 is that the fatty acid polyoxyethylene ether is not added.

[0050] Comparative example 5

[0051] The difference between the comparative example and the example 1 is that the polyether amine is not added.

[0052] Test Example

[0053] The flotation reagents obtained from Examples 1-2 and Comparative Examples 1-5 were used to perform flotation on spodumene ore. The specific conditions were as follows: the spodumene ore was selected from a granitic pegmatite type spodumene ore in western Sichuan, and the main lithium-containing minerals were spodumene, lithium-containing muscovite and lepidolite, and the main gangue minerals were feldspar, quartz and muscovite. The chemical element analysis results of the spodumene ore are shown in Table 1.

[0054] Table 1 Analysis results of spodumene ore

[0055] Component Li2O BeO SiO2 Al2O3 Fe2O3 Content / % 1.37 0.0329 72.70 15.92 1.78 Component CaO MgO K2O Na2O [Nb2O5] Content / % 0.52 0.31 2.42 3.53 0.011 Component [Ta2O5] P2O5 MnO Sn [Rb2O] Content / % 0.004 0.24 0.11 0.055 0.032 Component Cs2O CaF2 - - - Content / % 0.007 0.801 - - -

[0056] Flotation closed-circuit test conditions:

[0057] Grinding fineness: -0.075 mm content 80%;

[0058] Roughing sodium carbonate dosage 1500 g / t, 20 min; roughing sodium hydroxide dosage 500 g / t, 5 min; water glass 1000 g / t, 5 min; roughing calcium chloride dosage 80 g / t, 3 min; roughing reagent 1000 g / t, 3 min;

[0059] Scavenging I sodium hydroxide 50 g / t, 5 min; scavenging I reagent 200 g / t, 3 min;

[0060] Scavenging II sodium hydroxide 50 g / t, 5 min; scavenging II reagent 200 g / t, 3 min;

[0061] Cleaning I sodium carbonate 500 g / t, 5 min; cleaning I reagent 60 g / t, 3 min;

[0062] Cleaning II sodium carbonate 250 g / t, 5 min; cleaning II reagent 40 g / t, 3 min;

[0063] Cleaning III sodium carbonate 250 g / t, 5 min; cleaning III reagent 20 g / t, 3 min;

[0064] The results are shown in Table 2.

[0065] In the foregoing, the adding amount of the modified water glass and the water glass is same, the preparation method of the modified water glass is that 10wt% of water glass is taken, the pH value is adjusted to 8-9 to obtain water glass liquid; methyl triethoxysilane, water and ethanol are blended according to the volume ratio of 1:8:10, 10% of 0.1mol / L hydrochloric acid solution is added, after blending, it is treated at 45℃ for 50min to obtain silane liquid; ammonia water and ethanol are blended according to the volume ratio of 4:1, the ammonia water concentration is 0.5mol / L, the temperature is kept at 50℃, the water glass liquid, the silane liquid are sequentially added, the mass ratio of ammonia water, water glass liquid and silane liquid is 1:2:1, after constant temperature stirring at 45℃ for 75min, it is aged, centrifuged, filtered and dried to obtain the modified water glass.

[0066] Table 2 test results

[0067] Sample Li2O grade Li2O recovery Example 1-1 water glass 5.78 84.60 Example 1-2 modified water glass 5.86 84.75 Example 2 5.62 83.72 Comparative Example 1 4.83 76.49 Comparative Example 2 5.47 83.15 Comparative Example 3 5.33 81.24 Comparative Example 4 5.52 83.51 Comparative Example 5 5.58 83.84

[0068] The preferred embodiments of the present application have been described above with the aid of drawing. Obviously, the present application can be implemented not only in the form of the preferred embodiments, but also in the form of other embodiments. The present application covers all such modifications and changes as fall within the scope of the disclosure. The intention is therefore to be limited only by the scope of the appended claims, all changes coming within the meaning and range of equivalents thereof.

Claims

1. A spodumene flotation reagent characterised in that, The sulfonated oleic acid, phosphonic acid modified oleic acid hydroxamic acid, peroxide oleic acid soap, fatty acid polyoxyethylene ether, polyether amine, and alcohol compound.

2. The spodumene flotation reagent according to claim 1, characterized in that, The raw materials include 10-30 parts of sulfonated oleic acid, 10-30 parts of phosphonic acid modified oleic acid hydroxamic acid, 2-8 parts of peroxide oleic acid soap, 5-15 parts of fatty acid polyoxyethylene ether, 10-25 parts of polyether amine, and 5-15 parts of alcohol compound.

3. The spodumene flotation reagent according to claim 1, characterized in that, The polyether amine is polyether amine D230.

4. The spodumene flotation reagent of claim 1, characterized in that, The alcohol compound includes at least one of methanol, ethanol, and n-butanol.

5. The spodumene flotation reagent according to any one of claims 1 to 4, characterized in that, The preparation method of the phosphonic acid modified oleic acid hydroxamic acid includes: taking oleic acid and methanol as raw materials to obtain methyl oleate through reaction; reacting the methyl oleate with hydroxylamine hydrochloride to obtain oleic acid hydroxamic acid; and reacting the oleic acid hydroxamic acid with diethyl phosphite to obtain the phosphonic acid modified oleic acid hydroxamic acid.

6. A process for the preparation of a spodumene flotation reagent as claimed in any one of claims 1 to 5, characterised in that, The sulfonated oleic acid, phosphonic acid modified oleic acid hydroxamic acid, peroxide oleic acid soap, fatty acid polyoxyethylene ether, polyether amine, and alcohol compound are blended in proportion to obtain the flotation reagent.

7. A spodumene flotation process characterised in that, The flotation is performed by using the flotation reagent as claimed in any one of claims 1 to 5 or obtained by the preparation method as claimed in claim 6.

8. The spodumene flotation method according to claim 7, characterized in that, The lithium spodumene raw ore is ground to obtain the ore slurry; the pH adjusting agent, the depressant, the activator, and the flotation reagent are added into the ore slurry to obtain the rough concentrate and the rough tailings through roughing; the pH adjusting agent and the flotation reagent are added into the rough tailings to obtain the tailings through twice scavenging; The pH adjusting agent and the flotation reagent are added into the rough concentrate to obtain the lithium concentrate through three times of cleaning; and the middlings obtained in the scavenging and cleaning are sequentially returned to the previous stage.

9. The spodumene flotation method according to claim 8, characterized in that, The pH adjusting agent includes at least one of sodium carbonate and sodium hydroxide; and / or, the depressant includes at least one of water glass and carboxymethyl cellulose; and / or, the activator includes calcium chloride.

10. The spodumene flotation method according to claim 9, characterized in that, The water glass is modified by silane. The sulfonated oleic acid, phosphonic acid modified oleic acid hydroxamic acid, peroxide oleic acid soap, fatty acid polyoxyethylene ether, polyether amine, and alcohol compound.