CN109126750B

CN109126750B - Supported lithium adsorbent and preparation method thereof

Info

Publication number: CN109126750B
Application number: CN201710499377.XA
Authority: CN
Inventors: 段敏; 陈靖华; 高东; 徐茶清; 郭增艳
Original assignee: BYD Co Ltd
Current assignee: BYD Co Ltd
Priority date: 2017-06-27
Filing date: 2017-06-27
Publication date: 2020-08-07
Anticipated expiration: 2037-06-27
Also published as: CN109126750A

Abstract

The invention relates to the field of lithium adsorbents, in particular to a supported lithium adsorbent and a preparation method thereof. The supported lithium adsorbent includes: the support body and the porous microstructure formed by solidifying the lithium adsorbent powder and the adhesive in the holes of the support body. The supported lithium adsorbent has high adsorption capacity, adsorption selectivity and strength.

Description

Supported lithium adsorbent and preparation method thereof

Technical Field

The invention relates to the field of lithium adsorbents, in particular to a supported lithium adsorbent and a preparation method thereof.

Background

The preparation of the inorganic adsorbent is to add an adhesive into an inorganic adsorbent precursor for granulation, and the granulation method mainly comprises a physical method and a chemical method. The physical method mainly adopts PVC as an adhesive for extrusion granulation, and the extrusion process does not involve chemical reaction; the chemical method is mainly characterized in that an adhesive is added into an inorganic adsorbent precursor to form a two-phase interface for suspension granulation, and then heating is carried out to solidify the adhesive.

The physical method has the problems that the mechanical strength of the adsorbent is low, the water permeability of the adsorbent is poor, and the adsorption quantity is greatly reduced; although the mechanical strength of the adsorbent prepared by a chemical method is high, the consistency of the process is poor, and the adsorption performance is greatly reduced after granulation.

Disclosure of Invention

The invention aims to provide a novel supported lithium adsorbent and a preparation method thereof, wherein the supported lithium adsorbent has high adsorption capacity, adsorption selectivity and strength.

In order to achieve the above object, an aspect of the present invention provides a supported lithium adsorbent comprising: the support body and the porous microstructure formed by solidifying the lithium adsorbent powder and the adhesive in the holes of the support body.

In a second aspect, the present invention provides a method for preparing a supported lithium adsorbent, comprising:

(1) providing a feed liquid containing lithium adsorbent powder and an adhesive;

(2) mixing the feed liquid with a support body to obtain the support body with the feed liquid filled in a hole;

(3) and heating and curing the support body filled with the feed liquid in the hole.

A third aspect of the invention provides a supported lithium sorbent made by the above method.

The supported lithium adsorbent provided by the invention takes the porous filler body as the support body, and the porous microstructure is formed by solidifying the lithium adsorbent powder and the adhesive in the holes of the support body, so that the supported lithium adsorbent has higher adsorption capacity, adsorption selectivity and strength.

Drawings

Fig. 1 is an SEM image of the supported lithium adsorbent obtained in example 1;

fig. 2 is an SEM image of the supported lithium adsorbent obtained in example 2;

fig. 3 is an SEM image of the lithium adsorbent obtained in comparative example 1.

Detailed Description

The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual points, and between the individual points may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein.

In one aspect, the present invention provides a supported lithium adsorbent, comprising: the support body and the porous microstructure formed by solidifying the lithium adsorbent powder and the adhesive in the holes of the support body.

The lithium adsorbent in the prior art has the technical problems of low adsorption and desorption speed, poor adsorption selectivity and small adsorption and desorption amount, and the inventor finds that the adsorption capacity can be improved by increasing the surface area of the lithium adsorbent in research, but the effect is not obvious enough. In contrast, the inventors have obtained the technical solutions described in the present application in a large number of experiments. The support body provided by the invention is a porous filler body, has certain strength and can resist long-term erosion of salt lake or brine, and meanwhile, the pores are higher, so that the lithium adsorbent powder and the adhesive can form a more microscopic porous microstructure conveniently, and the technical problems of small adsorption and desorption amount and high breakage rate of the lithium adsorbent are solved.

According to the invention, the supported lithium adsorbent preferably takes a porous filler body as a support, and the support is porous and has more pores, so that the lithium adsorbent powder and the adhesive can be cured in the pores to form a porous microstructure with more micropores. The porous filler body is a hollow filler body having openings, and may be made of plastic, rubber, metal, or the like, and is preferably a plastic and/or rubber porous filler body in consideration of the bonding strength between the porous microstructure and the support.

According to the invention, the porous filler body can have various morphologies, such as one or more of hollow polyhedral spheres (generally, fan-shaped blades with two hemispheres are staggered with each other, such as hollow spheres prepared by the Yixing market sub-energy plastic machinery plant), pall rings, ladder rings, fish net-shaped rotary type suspension spheres, MBBR biological fillers (such as related products of the small and old age special plastic products Co., Ltd., China county), conjugate rings, hell rings, Natt rings and the like.

According to the invention, the diameter of the porous filler body is preferably 100mm or less, preferably 10 to 80mm, more preferably 20 to 70mm, for example 30 to 50 mm. Preferably, the porous filler bodies have pores with a pore diameter of 0.1 to 20mm, preferably 0.5 to 15mm, more preferably 1 to 10mm, for example 5 to 8 mm. The diameter herein refers to the largest dimension of the porous filler body, wherein when the porous filler body is spherical, the diameter represents the diameter of the sphere; when the porous filler body is ellipsoidal, the diameter represents the largest diameter thereof; when the porous filler body is a cuboid, the diameter represents the size of the long side of the cuboid; when the porous filler body is irregular in shape, the diameter represents the equivalent diameter (corresponding to the particle size) of its equivalent sphere.

According to the present invention, the porosity of the porous filler body is preferably 20% or more, preferably 20 to 99%, preferably 40 to 99%, more preferably 50 to 99%, for example 60 to 95%.

According to the invention, a porous microstructure is formed among pores of the support, and the porous microstructure is formed by solidifying the lithium adsorbent powder and the adhesive. Wherein, preferably, the porous microstructure has pores with a pore diameter of 0.5 to 10 μm, preferably 1 to 5 μm. In a preferred embodiment of the invention, the porous microstructure has pores with an average pore diameter of 0.5 to 10 μm, more preferably 1 to 5 μm.

According to the present invention, in the porous microstructure, the amounts of the lithium adsorbent powder and the adhesive may vary within a wide range, and preferably, the weight ratio of the lithium adsorbent powder to the adhesive is 100: 10-50, preferably 100: 15-40, more preferably 100: 20-30, for example 100: 20-27.

According to the invention, the lithium adsorbent powder can be various conventional lithium adsorbent powder materials, such as one or more of an aluminum salt lithium adsorbent, a lithium titanium oxide adsorbent and a lithium manganese oxide type lithium adsorbent, wherein the lithium adsorbent powder can be a commercial product or prepared by a method conventional in the art, for example, the preparation method of the aluminum salt lithium adsorbent comprises the steps of mixing aluminum hydroxide and lithium hydroxide (the amount of the aluminum hydroxide and the lithium hydroxide is 1.8-2.2: 1 according to a molar ratio of Al to L i), for 20-40min by using a high-speed stirrer, heating in an air atmosphere (for 2-4h at 180-220 ℃), adding water (the amount of the water is 2-5: 1 according to a weight ratio of the water to the powder), aging the obtained mixture (for 2-5h at 50-80 ℃), cooling, adding hydrochloric acid to the pH of an upper aqueous phase to 4-6, separating and drying to obtain the aluminum salt adsorbent.

According to the invention, the adhesive can be cured and forms a porous microstructure with the lithium adsorbent powder, preferably, the adhesive is a resin adhesive and/or a rubber adhesive, wherein the adhesive contains a curable material and a curing agent. Among them, the curable material in the resin-based adhesive is preferably one or more of bisphenol a type epoxy resin (e.g., bisphenol a type epoxy resin E-51), hydrogenated bisphenol a type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol P type epoxy resin, methylol bisphenol a epoxy resin, brominated bisphenol a epoxy resin, phenol novolac epoxy resin (EPN), o-cresol novolac epoxy resin (ECN), epoxy resorcinol formaldehyde resin, tetraphenol ethane epoxy resin, naphthol novolac epoxy resin (EEPN), glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, TDE-85 epoxy resin, and the like. The curable material in the rubber adhesive can be one or more of neoprene, nitrile rubber, styrene butadiene rubber, silicon rubber and the like.

According to the present invention, the lithium adsorbent powder, the support and the adhesive are as described above, and the present invention is not described herein again.

Preferably, the weight ratio of the lithium adsorbent powder to the adhesive is 100: 5-40, preferably 100: 5-30, more preferably 100: 10-20, for example 100: 10-15.

According to the present invention, the curing agent is various curing agents which can be cured, for example, basic curing agents (including aliphatic diamines and polyamines, aromatic polyamines, other nitrogen-containing compounds and modified aliphatic amines), acidic curing agents (including organic acids, acid anhydrides and boron trifluoride and complexes thereof), addition type curing agents, catalytic type curing agents, and the like, and specific examples thereof may be, for example, one or more of ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, diethylaminopropylamine, maleic anhydride, phthalic anhydride, and the like. The curing agent is not particularly limited in the present invention, and any curing agent conventional in the art can be used, wherein preferably, the adhesive comprises a curable material and a curing agent, wherein the curable material and the curing agent are used in a weight ratio of 100: 20-80, preferably 100: 30-60.

According to the invention, the solvent adopted by the feed liquid is preferably one or more of water, acetone, methanol, ethanol, ethylene glycol, propylene glycol and isopropanol. The amount of the solvent can vary within a wide range, and preferably, the weight ratio of the lithium adsorbent powder to the solvent is 100: 5-20, preferably 100: 10-15.

According to the invention, a surfactant and/or a pore-forming agent can also be introduced into the feed liquid.

The surfactant may include one or more of carboxylates (sodium alginate, sodium pectate, sodium humate, sodium carboxymethylcellulose, etc.), sulfonates (calcium dodecylbenzene sulfonate, sodium tetradecylbenzene sulfonate, etc.), quaternary ammonium salts (dodecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, etc.), PEO derivatives (octylphenol polyoxyethylene ether, nonylphenol polyoxyethylene ether, dodecylphenol polyoxyethylene ether, etc.), and the like. Preferably, the weight ratio of the lithium adsorbent powder to the surfactant is 100: 0 to 10, preferably 100: 1-8.

The porogen may include, for example, one or more of metal chloride (zinc chloride, cobalt chloride, lithium chloride, etc.), carbonate and bicarbonate (ammonium bicarbonate, sodium bicarbonate, calcium carbonate, magnesium carbonate, etc.), organic solvent (polyvinyl alcohol, polyethylene glycol, n-pentane, n-hexane, n-heptane, petroleum ether, etc.), azo compound, sulfonyl hydrazide compound, nitroso compound, etc. Preferably, the weight ratio of the lithium adsorbent powder to the pore-forming agent is 100: 0 to 10, preferably 100: 1-8.

According to the invention, in the step (2), the feed liquid is mixed with the porous filler body, the volume of the feed liquid and the porous filler body can be equal, or the volume of the feed liquid is more than that of the porous filler body, or the volume of the feed liquid can be less than that of the porous filler body, preferably, the dosage of the feed liquid can cover the porous filler body, so that the volume ratio of the feed liquid to the porous filler body can be 1-4: 1.

according to the present invention, in step (3), preferably, the heat curing conditions include: the temperature is 20-120 ℃ and the time is 1-5 h. More preferably, the conditions for heat curing include: the temperature is 80-120 ℃ and the time is 1-2 h. Through the heating curing treatment, the adhesive contained in the porous filler body can be cured, and a porous microstructure is formed between pores of the porous filler body together with the dispersed lithium adsorbent powder; the porous microstructure can be a porous microstructure with a microporous structure formed by an adhesive cured by heating under the action of a solvent evaporation, gas burst generated by decomposition of an optional pore-forming agent and the like, an optional surfactant and the like in the heating and curing process. Thus, the supported lithium adsorbent which takes the porous filler body as a support body and is formed by solidifying the lithium adsorbent powder and the adhesive between pores on the support body is obtained.

The supported lithium adsorbent provided by the invention takes the porous filler body as the support body, and the porous microstructure is formed by solidifying the lithium adsorbent powder and the adhesive between pores on the support body.

The present invention will be described in detail below by way of examples.

In the following examples:

the hollow polyhedral ball filler is a hollow polyhedral ball filler which is purchased from Shenzhen Benda plastic Co., Ltd and has two fan-shaped blades with hemispheres staggered with each other, the diameter of the ball is 50mm, and the porosity is 99%.

Preparation example 1

This preparation example is used to illustrate the preparation of lithium adsorbent powder.

(1) Mixing aluminum hydroxide and lithium hydroxide monohydrate (in such an amount that the molar ratio of Al to L i is 2: 1) in a high-speed mixer for 30min, and heating the resulting mixture in air at 200 ℃ for 3 h;

(2) adding the powder obtained in the step (1) into a proper amount of deionized water (the weight ratio of water to the powder is 3: 1), uniformly stirring, aging at 70 ℃ for 3 hours, cooling, and adding hydrochloric acid to adjust the pH value of an upper-layer water phase to 5.3;

(3) and separating and drying the powder.

Example 1

This example illustrates the supported lithium sorbent of the invention and its method of preparation.

(1) Stirring and mixing bisphenol A type epoxy resin E-51 (10 parts by weight based on dry weight, purchased from Aichuan chemical industry Co., Ltd., Guangzhou), epoxy curing agent (5 parts by weight based on dry weight, purchased from GG-6689 brand of solid specialty chemical, Jiangmen) and acetone (10 parts by weight) with the aluminum salt lithium adsorbent powder (75 parts by weight) obtained in preparation example 1 to obtain a feed liquid;

(2) adding the hollow polyhedral sphere filler bodies into the feed liquid (the volume ratio of the total amount of the hollow polyhedral sphere filler bodies to the feed liquid is 1: 1.5), and uniformly stirring;

(3) and (3) putting the hollow polyhedral sphere filler body loaded with the feed liquid into an oven, and heating and curing for 1h at 100 ℃ to obtain the loaded lithium adsorbent A1.

As can be seen from an SEM spectrogram (shown in figure 1), a porous microstructure is formed among pores of the hollow polyhedral sphere filler body of the supported lithium adsorbent, and the pore diameter of the porous microstructure is 1-3 mu m.

Example 2

According to the method described in example 1, except that 5 parts by weight of octyl phenol polyoxyethylene ether OP-10 surfactant (obtained from Haian petrochemical plant of Jiangsu province) was further introduced into the feed liquid of step (1), the supported lithium adsorbent A2 was finally obtained.

As can be seen from an SEM spectrogram (shown in figure 2), a porous microstructure is formed among pores of the hollow polyhedral sphere filler body of the supported lithium adsorbent, and the pore diameter of the porous microstructure is 2-5 mu m.

Example 3

(1) Stirring and mixing bisphenol A type epoxy resin E-51 (purchased from Aichuan chemical Co., Ltd., Guangzhou city, 15 parts by weight based on dry weight), an epoxy curing agent (purchased from GG-6689 brand of solid specialty chemical, Jiangmen city, 5 parts by weight based on dry weight), ethylene glycol (15 parts by weight) and the aluminum salt lithium adsorbent powder (75 parts by weight) obtained in preparation example 1 to obtain a feed liquid;

(2) adding the hollow polyhedral sphere filler bodies into the feed liquid (the volume ratio of the total amount of the hollow polyhedral sphere filler bodies to the feed liquid is 1: 2), and uniformly stirring;

(3) and (3) putting the hollow polyhedral sphere filler body loaded with the feed liquid into an oven, and heating and curing for 1h at 120 ℃ to obtain the loaded lithium adsorbent A3.

According to SEM spectrogram, a porous microstructure is formed among pores of the hollow polyhedral sphere filler of the supported lithium adsorbent, and the pore diameter of the porous microstructure is 0.5-2 mu m.

Example 4

According to the method described in example 1, except that the amount of bisphenol a type epoxy resin E-51 used in step (1) was 25 parts by weight (dry weight basis), supported lithium adsorbent a4 was finally obtained.

According to SEM spectrogram, a porous microstructure is formed among pores of the hollow polyhedral sphere filler of the supported lithium adsorbent, and the pore diameter of the porous microstructure is 1-5 microns.

Example 5

According to the method described in example 1, except that the bisphenol a type epoxy resin E-51 was used in an amount of 5 parts by weight (dry weight basis) in step (1), supported lithium adsorbent a5 was finally obtained.

According to SEM spectrogram, a porous microstructure is formed among pores of the hollow polyhedral sphere filler of the supported lithium adsorbent, and the pore diameter of the porous microstructure is 1-2 microns.

Comparative example 1

According to the method described in example 1, except that the feed liquid obtained in step (1) was subjected to extrusion granulation by using an extruder instead of the hollow polyhedral sphere filler body, and dried to obtain the lithium adsorbent D1.

As can be seen from the SEM spectra (as shown in fig. 3), the lithium adsorbent did not form a considerable porous microstructure.

Test example 1

The lithium adsorbent was subjected to tests of adsorption capacity, adsorption selectivity and breakage rate, and the results thereof are shown in table 2, in which:

the test procedure for adsorption capacity and adsorption selectivity includes: by using a static adsorption method, 10g of lithium adsorbent is added into 1000g of salt lake brine (the initial concentration of each metal ion in the salt lake brine is shown in table 1), stirred for 1 hour, filtered and tested for the lithium content of the filtrate.

Adsorption capacity (lithium content in brine before adsorption-lithium content in brine after adsorption)/mass of adsorbent;

and the adsorption selectivity (1-ratio of magnesium and lithium in brine before adsorption/ratio of magnesium and lithium in brine after adsorption) is × 100%.

TABLE 1

Element(s)

B

Ca

Li

Mg

Na

Mg/Li

Concentration of

97ppm

485ppm

127ppm

4.953％

1.714％

390

The test process of the breakage rate comprises the following steps: filling a lithium adsorbent into a container to be impacted, injecting brine into equipment by using a booster pump for cyclic impact, and measuring the breakage rate of the lithium adsorbent after 24 hours of impact, wherein the calculation formula is as follows:

the percent crush is × 100% mass of crushed particles of sorbent after impact/mass of sorbent particles before impact.

TABLE 2

Lithium adsorbent	Adsorption capacity (mg/g)	Adsorption selectivity	Rate of breakage
				A1	10	97％	0.5％
A2	11	96％	0.8％
				A3	9	96％	0.4％
A4	6	92％	1.5％
				A5	8	95％	2.1％
D1	4	89％	5％

As can be seen from the data in Table 2, the supported lithium adsorbent provided by the invention has high adsorption capacity, adsorption selectivity and strength, wherein the adsorption capacity is more than 6mg/g, preferably more than 8mg/g, and more preferably 9-12 mg/g; the adsorption selectivity is 90% or more, preferably 95% or more, and more preferably 96% or more; the breakage rate is 2.5% or less, preferably 1.5% or less, and more preferably less than 1%.

The preferred embodiments of the present invention have been described above in detail, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, many simple modifications can be made to the technical solution of the invention, including combinations of various technical features in any other suitable way, and these simple modifications and combinations should also be regarded as the disclosure of the invention, and all fall within the scope of the invention.

Claims

1. A supported lithium sorbent, comprising: the support body and the porous microstructure formed by solidifying the lithium adsorbent powder and the adhesive in the holes of the support body;

wherein the weight ratio of the lithium adsorbent powder to the adhesive is 100: 10-50.

2. The supported lithium sorbent of claim 1, wherein the support is a porous filler body.

3. The supported lithium sorbent of claim 2, wherein the porous filler bodies have a diameter of 100mm or less.

4. The supported lithium sorbent of claim 2, wherein the porous filler bodies have a diameter of 10-80 mm.

5. The supported lithium sorbent of claim 2, wherein the porous filler bodies have a diameter of 20-70 mm.

6. The supported lithium sorbent of claim 2, wherein the porous filler bodies have pores with a pore size of 0.1-20 mm.

7. The supported lithium sorbent of claim 2, wherein the porous filler bodies have pores with a pore size of 0.5-15 mm.

8. The supported lithium sorbent of claim 2, wherein the porous filler bodies have pores with a pore size of 1-10 mm.

9. The supported lithium sorbent of claim 2, wherein the porosity of the porous filler body is from 20-99%.

10. The supported lithium sorbent of claim 2, wherein the porosity of the porous filler body is from 40-99%.

11. The supported lithium sorbent of claim 2, wherein the porous filler body has a porosity of 50-99%.

12. The supported lithium sorbent of any one of claims 1-11, wherein the porous microstructure has pores with a pore size of 0.5-10 μ ι η.

13. The supported lithium sorbent of any one of claims 1-11, wherein the porous microstructure has pores with a pore size of 1-5 μ ι η.

14. The supported lithium sorbent of any of claims 1-11, wherein the weight ratio of the lithium sorbent powder to the adhesive is 100: 15-40.

15. The supported lithium sorbent of any of claims 1-11, wherein the weight ratio of the lithium sorbent powder to the adhesive is 100: 20-30.

16. The supported lithium sorbent of any one of claims 1-11, wherein the lithium sorbent powder is one or more of a lithium aluminum salt sorbent, a lithium titanium oxide sorbent, and a lithium manganese oxide-type lithium sorbent.

17. A method for preparing a supported lithium adsorbent, the method comprising:

(3) heating and curing the support body filled with the feed liquid in the hole;

in the step (1), the weight ratio of the lithium adsorbent powder to the adhesive is 100: 10-50.

18. The method of claim 17, wherein the support is a porous filler body.

19. The method of claim 18, wherein the porous filler bodies have a diameter of 100mm or less.

20. The method of claim 18 wherein the porous filler bodies have a diameter of 10-80 mm.

21. The method of claim 18, wherein the porous filler bodies have a diameter of 20-70 mm.

22. The method of claim 18, wherein the porous filler bodies have pores with a pore size of 0.1-20 mm.

23. The method of claim 18, wherein the porous filler bodies have pores with a pore size of 0.5-15 mm.

24. The method of claim 18, wherein the porous filler bodies have pores with a pore size of 1-10 mm.

25. The method of claim 18 wherein the porous filler body has a porosity of 20-99%.

26. The method of claim 18 wherein the porous filler body has a porosity of 40-99%.

27. The method of claim 18 wherein the porous filler body has a porosity of 50-99%.

28. The method of any of claims 17-27, wherein the weight ratio of the lithium sorbent powder to the adhesive is 100: 15-40.

29. The method of any of claims 17-27, wherein the weight ratio of the lithium sorbent powder to the adhesive is 100: 20-30.

30. The method according to any one of claims 17-27, wherein the adhesive comprises a curable material and a curing agent, wherein the curable material and the curing agent are used in a weight ratio of 100: 20-80.

31. The method of claim 30, wherein the curable material and curing agent are used in a weight ratio of 100: 30-60.

32. The method of any of claims 17-27, wherein the lithium adsorbent powder is one or more of a lithium aluminum salt adsorbent, a lithium titanium oxide adsorbent, and a lithium manganese oxide-type lithium adsorbent.

33. The method according to any one of claims 17-27, wherein the feed solution employs a solvent selected from one or more of water, acetone, methanol, ethanol, ethylene glycol, propylene glycol, and isopropanol.

34. The method of claim 33, wherein the lithium adsorbent powder and the solvent are used in a weight ratio of 100: 5-20.

35. The method of claim 33, wherein the lithium adsorbent powder and the solvent are used in a weight ratio of 100: 10-15.

36. The method according to any one of claims 17-27, wherein a surfactant and/or a porogen is further introduced into the feed solution.

37. The method of claim 36, wherein the lithium sorbent powder and the surfactant are used in a weight ratio of 100: 0-10.

38. The method of claim 36, wherein the lithium sorbent powder and the surfactant are used in a weight ratio of 100: 1-8.

39. The method of claim 36, wherein the weight ratio of the lithium adsorbent powder to the pore-forming agent is 100: 0-10.

40. The method of claim 36, wherein the weight ratio of the lithium adsorbent powder to the pore-forming agent is 100: 1-8.

41. The method according to any one of claims 17 to 27, wherein in step (3), the conditions for heat curing comprise: the temperature is 20-120 ℃ and the time is 1-5 h.