MS-MIL-101(Al), a dual-framework MOF material for cobalt ion separation, and its preparation method.

Abstract

The present invention relates to the field of separation technology, and specifically discloses a double-framework MOFs material MS-MIL-101 (Al) for cobalt ion separation and a preparation method thereof, comprising the following components: molecular sieve (3A), metal ion (Al) source, terephthalic acid, concentrated hydrochloric acid, ethanol and deionized water. Aluminum-oxygen tetrahedrons in silicon-aluminum molecular sieves can provide a good metal ion source for the generation of MOFs, which is conducive to the generation of MOFs skeletons, and silicon-oxygen units with a good skeleton structure provide a natural guarantee for the stability of the MOFs structure. Using terephthalic acid as a ligand, a MOFs material MS-MIL-101 (Al) with a double-framework structure is prepared in one pot by a hydrothermal method, which has the characteristics of simple preparation, low price and high stability.

Description

Technical Field

[0001] The present invention relates to the field of separation technology, and in particular to a double-framework MOFs material MS-MIL-101 (Al) for cobalt ion separation and a preparation method thereof. Background Art

[0002] At present, with the rapid development of the new energy vehicle industry, electric vehicles are gradually being studied, applied and popularized. Cobalt is widely used in the production of ternary lithium batteries. The main methods for separating cobalt ions include solvent extraction, chemical precipitation, microbial method and membrane separation. Among them, membrane separation has the characteristics of simple operation, energy saving and environmental protection, high efficiency and flexibility, small equipment footprint and easy to scale up production. It is considered to be one of the methods with great industrial application potential. The key to membrane separation technology lies in membrane materials. There are many types of separation membrane materials currently under development, including organic polymer membrane materials and inorganic membrane materials. Among them, organic polymer membrane materials are widely used in the separation of organic polymer membrane materials and inorganic membrane materials. Molecular membranes are currently the most widely used and most commercialized. The main materials include cellulose, polysulfone and polyimide, etc., which are low-priced, diverse and have good film-forming properties. Inorganic membrane materials are mainly divided into two categories: dense membranes and microporous membranes, which have the characteristics of high selectivity and good stability. In order to fully combine the advantages of organic polymer membranes and inorganic membrane materials, inorganic fillers are added to the polymer substrate to obtain a mixed matrix membrane. This membrane has the common advantages of inorganic fillers and organic polymers, and has good film-forming properties, excellent thermal stability and chemical stability, and certain separation properties.

[0003] However, in the prior art, the inorganic fillers developed are generally characterized by limited types, narrow pore size range, and poor controllability, resulting in the prepared mixed matrix membranes having low separation efficiency and limited scope of application, and obvious defects when used for metal ion separation. Summary of the invention

[0004] The purpose of the present invention is to provide a dual-skeleton MOFs material MS-MIL-101 (Al) for cobalt ion separation and a preparation method thereof, aiming to solve the technical problem that the inorganic fillers developed in the prior art generally have the characteristics of limited types, narrow pore size range, and poor controllability, resulting in the prepared mixed matrix membrane having low separation efficiency and limited application range, and obvious defects when used for metal ion separation.

[0005] To achieve the above object, the present invention adopts a double-framework MOFs material MS-MIL-101 (Al) for cobalt ion separation, comprising the following components:

[0006] Molecular sieve (3A), metal ion (Al) source, terephthalic acid, concentrated hydrochloric acid, ethanol and deionized water.

[0007] The present invention also provides a preparation method of a double-framework MOFs material MS-MIL-101 (Al) for cobalt ion separation, which is applied to the double-framework MOFs material MS-MIL-101 (Al) for cobalt ion separation described above, and comprises the following steps:

[0008] The MOFs material was prepared using molecular sieve as the framework and metal ion (Al) source and terephthalic acid. 1.17 g of molecular sieve (3A) and 1.66 g of terephthalic acid were weighed and dispersed in 300 ml of deionized water.

[0009] Add 2.0 mL of concentrated hydrochloric acid and stir evenly;

[0010] After ultrasonic treatment for 20 min, the mixture was transferred to a hydrothermal reactor and reacted at 120 °C for 24 h before cooling;

[0011] The resulting product was washed with deionized water and ethanol to obtain MS-MIL-101(Al).

[0012] The performance evaluation of the prepared MS-MIL-101 (Al) includes the following steps:

[0013] Take 50mL of 10mg / L cobalt-containing wastewater and adjust its pH value to 5-9 with 0.1mol / L NaOH solution;

[0014] Add 10 mg of MS-MIL-101 (Al);

[0015] The cobalt ions in the wastewater are adsorbed at 15°C to 45°C for a treatment time of 0 to 10 hours.

[0016] Wherein, the pH value of the cobalt-containing wastewater is adjusted to 8.3.

[0017] Wherein, the adsorption temperature of the MS-MIL-101(Al) is 25°C.

[0018] Among them, the adsorption time of MS-MIL-101 (Al) on cobalt-containing wastewater is 4 hours.

[0019] The invention discloses a double-framework MOFs material MS-MIL-101 (Al) for separating cobalt ions and a preparation method thereof. The aluminum-oxygen tetrahedron in the silicon-aluminum molecular sieve can provide a good metal ion source for the generation of MOFs, which is beneficial to the generation of the MOFs framework, and the silicon-oxygen unit with a good framework structure provides a natural guarantee for the stability of the MOFs structure. The MOFs material MS-MIL-101 (Al) with a double-framework structure is prepared in one pot by a hydrothermal method using terephthalic acid as a ligand. When the MS-MIL-101 (Al) is used to remove cobalt ions in a leachate, the pH value of the leachate should be adjusted to 5.0-9.0. At a temperature range of 15°C-45°C, the MS-MIL-101 (Al) material is added to adsorb the leachate, and the time for adsorbing the leachate should not be less than 2 hours. The prepared MS-MIL-101 (Al) material has the characteristics of simple preparation, low price and high stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 It is the XRD analysis chart of MS-MIL-101(Al) of the present invention.

[0022] Figure 2 It is the infrared analysis chart of MS-MIL-101(Al) of the present invention.

[0023] Figure 3 It is a SEM picture of MS-MIL-101(Al) of the present invention.

[0024] Figure 4 This is an adsorption test diagram of Example 1 of the present invention.

[0025] Figure 5 This is an adsorption test diagram of Example 2 of the present invention.

[0026] Figure 6 It is an adsorption test diagram of Example 3 of the present invention.

[0027] Figure 7 It is an adsorption test diagram of Example 4 of the present invention. DETAILED DESCRIPTION

[0028] The present invention provides a double-framework MOFs material MS-MIL-101 (Al) for cobalt ion separation, comprising the following components:

[0029] Molecular sieve (3A), metal ion (Al) source, terephthalic acid, concentrated hydrochloric acid, ethanol and deionized water.

[0030] The present invention also provides a preparation method of a double-framework MOFs material MS-MIL-101 (Al) for cobalt ion separation, which is applied to the double-framework MOFs material MS-MIL-101 (Al) for cobalt ion separation described above, and comprises the following steps:

[0031] The MOFs material was prepared using molecular sieve as the framework and metal ion (Al) source and terephthalic acid. 1.17 g of molecular sieve (3A) and 1.66 g of terephthalic acid were weighed and dispersed in 300 ml of deionized water.

[0032] Add 2.0 mL of concentrated hydrochloric acid and stir evenly;

[0033] After ultrasonic treatment for 20 min, the mixture was transferred to a hydrothermal reactor and reacted at 120 °C for 24 h before cooling;

[0034] The resulting product was washed with deionized water and ethanol to obtain MS-MIL-101(Al).

[0035] Further, the prepared MS-MIL-101 (Al) is subjected to a performance evaluation, comprising the following steps:

[0036] Take 50mL of 10mg / L cobalt-containing wastewater and adjust its pH value to 5-9 with 0.1mol / L NaOH solution;

[0037] Add 10 mg of MS-MIL-101 (Al);

[0038] The cobalt ions in the wastewater are adsorbed at 15°C to 45°C for a treatment time of 0 to 10 hours.

[0039] Furthermore, the pH value of the cobalt-containing wastewater is adjusted to 8.3.

[0040] Furthermore, the adsorption temperature of the MS-MIL-101(Al) is 25°C.

[0041] Furthermore, the adsorption time of the MS-MIL-101(Al) on the cobalt-containing wastewater is 4 hours.

[0042] Embodiment 1:

[0043] Take 50mL of a cobalt-containing solution with a concentration of 10.0mg / L, adjust its pH value to 5.0-9.0 with a 0.1mol / L HNO3 solution, then add 10.0mg of MS-MIL-101(Al), and then place it in a constant temperature oscillator at 25°C to adsorb cobalt ions in the leachate. After oscillating at 150rpm for 24.0h, take 3.0mL of the adsorbed mixed solution and centrifuge it at 12000rpm for 5min on a centrifuge; then take 1mL of the supernatant in a 25mL volumetric flask, add 1.0mL of HAc-NaAc buffer solution with a pH of 4.7 and 1.0mL of nitroso-R salt solution with a concentration of 4g / L, and make up to volume with distilled water. The adsorption amount of MS-MIL-101(Al) is determined by a UV-visible spectrophotometer. Figure 4 It can be seen that when pH = 8.3, the adsorption amount is the largest, which is 46.4 mg / g.

[0044] Embodiment 2:

[0045] Take 50mL of a 10mg / L cobalt-containing solution, adjust its pH to 8.3 with a 0.1mol / L NaOH solution, add 10.0mg of adsorbent MS-MIL-101(Al), and then place it in a constant temperature oscillator at 25°C to adsorb cobalt ions in the solution. After oscillating at 150rpm for 0.2, 0.5, 1, 2, 3, 4, 6, 7, 8, and 10h, take 3.0mL of the adsorbed mixed solution and centrifuge it at 12000rpm for 5min on a centrifuge; then take 1mL of the supernatant in a 25mL volumetric flask, add 1.0mL of a pH 4.7 HAc-NaAc buffer solution and 1.0mL of a 4g / L nitroso-R salt solution, make up to volume with distilled water, and determine the adsorption amount of MS-MIL-101(Al) using a UV-visible spectrophotometer, as shown in Figure 2. Figure 5 shown.

[0046] Embodiment 3:

[0047] Take 50mL of cobalt-containing solutions with concentrations of 10, 20, 30, 40, 50, 60, and 70mg / L, adjust the pH to 8.3 with 0.1mol / L NaOH solution, add 10.0mg of adsorbent MS-MIL-101 (Al), and then place it in a constant temperature oscillator at 25°C to adsorb cobalt ions in the wastewater. After oscillating at 150rpm for 4.0h, take 3.0mL of the adsorbed mixed solution and centrifuge it at 12000rpm for 5min on a centrifuge; then take 1mL of the supernatant in a 25mL volumetric flask, add 1.0mL of HAc-NaAc buffer solution with a pH of 4.7 and 1.0mL of nitroso-R salt solution with a concentration of 4g / L, and after making up to volume with distilled water, use a UV-visible spectrophotometer to determine the adsorption amount of MS-MIL-101 (Al), such as Figure 6 shown.

[0048] Embodiment 4:

[0049] Take 50mL of a cobalt-containing solution with a concentration of 10mg / L, adjust its pH to 8.3 with a 0.1mol / L NaOH solution, then add 10.0mg of adsorbent MS-MIL-101(Al), and then place it in a constant temperature oscillator at 15, 25, 35, and 45°C to adsorb cobalt ions in the wastewater. After oscillating at 150rpm for 4.0h, take 3.0mL of the adsorbed mixed solution and centrifuge it at 12000rpm for 5min on a centrifuge; then take 1mL of the supernatant in a 25mL volumetric flask, add 1.0mL of HAc-NaAc buffer solution with a pH of 4.7 and 1.0mL of nitroso-R salt solution with a concentration of 4g / L, and after making up to volume with distilled water, use a UV-visible spectrophotometer to determine the adsorption amount of MS-MIL-101(Al), as shown in Figure 2. Figure 7 shown.

[0050] What is disclosed above is only a preferred embodiment of the present invention, and it certainly cannot be used to limit the scope of rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiment and equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. A double-framework MOFs material MS-MIL-101 (Al) for cobalt ion separation, characterized in that: Includes the following ingredients: Silica-alumina molecular sieve, terephthalic acid, concentrated hydrochloric acid, ethanol and deionized water; The preparation method comprises the following steps: Weigh 1.17 g of silica-alumina molecular sieve and 1.66 g of terephthalic acid and disperse them in 300 ml of deionized water; Add 2.0 mL of concentrated hydrochloric acid and stir evenly; After ultrasonic treatment for 20 min, the mixture was transferred to a hydrothermal reactor and reacted at 120 °C for 24 h before cooling; The resulting product was washed with deionized water and ethanol to obtain MS-MIL-101(Al).

2. The double-framework MOFs material MS-MIL-101 (Al) for cobalt ion separation according to claim 1, characterized in that: The performance evaluation of the prepared MS-MIL-101(Al) includes the following steps: Take 50mL of 10mg / L cobalt-containing wastewater and adjust its pH value to 5-9 with 0.1mol / L NaOH solution; Add 10 mg of MS-MIL-101 (Al); The cobalt ions in the wastewater are adsorbed at 15°C to 45°C for a treatment time of 0 to 10 hours.

3. The double-framework MOFs material MS-MIL-101 (Al) for cobalt ion separation according to claim 2, characterized in that: The pH value of the cobalt-containing wastewater was adjusted to 8.

3.

4. The double-framework MOFs material MS-MIL-101 (Al) for cobalt ion separation according to claim 2, characterized in that: The adsorption temperature of the MS-MIL-101(Al) is 25°C.

5. The double-framework MOFs material MS-MIL-101 (Al) for cobalt ion separation according to claim 4, characterized in that: The adsorption time of the MS-MIL-101 (Al) for cobalt-containing wastewater is 4 hours.

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