Application of zinc-based MOF material
By preparing zinc-based MOF materials as adsorbents, the problems of low ethylene adsorption capacity and insufficient stability in existing technologies have been solved, achieving efficient separation and adsorption of ethylene, ethane, and acetylene, extending the storage and transportation period of fruits and vegetables and reducing environmental risks.
Patent Information
- Application Number
- CN202511097241.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-06
- Publication Date
- 2025-11-11
AI Technical Summary
In existing technologies, ethylene adsorbents have low adsorption capacity and insufficient stability. Commercial potassium permanganate is difficult to regenerate during the adsorption process and poses environmental risks, leading to the problem of ethylene accumulation and rotting of fruits and vegetables during storage and transportation.
Zinc-based MOF materials are used as adsorbents. Zinc-based MOF materials with three-dimensional structures and specific pore sizes are prepared by solvothermal method. They are used to adsorb and separate C2 hydrocarbon gases, including ethylene, ethane and acetylene, and are suitable for fruit preservation.
It achieves efficient adsorption and separation of ethylene, ethane and acetylene, significantly extending the shelf life of fruits and vegetables, reducing storage costs and ensuring environmental safety.
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Figure CN120919973A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of adsorption separation, and specifically relates to a new application of a zinc-based MOF material. Background Technology
[0002] Ethylene (C2H4), a plant hormone, plays a crucial role in regulating the ripening and senescence of fruits and vegetables. During storage and transportation, the accumulation of ethylene often leads to overripeness, rot, and spoilage, resulting in loss of commercial value, significantly shortened shelf life, and severe economic losses. Therefore, effectively reducing and controlling ethylene concentration and adopting safe and efficient preservation methods are of great significance for ensuring the quality of stored and transported fruits and vegetables and reducing post-harvest losses.
[0003] Low-temperature preservation is a widely used method for storing and transporting fresh fruits and vegetables. Other physical methods (such as irradiation, high-pressure treatment, ultrasound, and modified atmosphere packaging) and chemical methods (such as chemical fungicides) are also frequently used. Although these methods can delay the decay of fruits and vegetables to some extent, they still have many limitations, such as high cost, complex operation, environmental pollution, and potential health risks. Therefore, developing safe, environmentally friendly, green, and efficient new technologies for fruit and vegetable preservation is of great practical significance and urgent need.
[0004] Adsorption methods have garnered significant attention in the field of gas removal due to their ease of operation, low cost, and environmental friendliness; the core of this approach lies in the selection of adsorbents. However, the selection of highly efficient ethylene adsorbents suitable for fruit preservation remains relatively limited due to the need to simultaneously meet requirements such as controllable cost, good stability, and low toxicity. Patent CN11065259A discloses an ethylene adsorbent based on aluminosilicate phosphate molecular sieve, which utilizes the principle of spontaneous monolayer dispersion to load monovalent copper compounds within the molecular sieve to enhance its ethylene adsorption capacity. However, this adsorbent still suffers from low ethylene adsorption capacity (only 0.93-1.80 mmol / g) and insufficient stability. While commercially available potassium permanganate (KMnO4) granules show significant ethylene removal efficiency, they irreversibly convert to manganese dioxide (MnO2) during adsorption, making them difficult to regenerate and reuse, and posing certain environmental and food safety risks.
[0005] Therefore, there is an urgent need to develop a high-performance, efficient, stable, green and safe ethylene adsorbent to meet the needs of ethylene removal in the storage and preservation of fruits at room temperature, thereby extending shelf life and significantly reducing long-term storage costs and energy consumption. Summary of the Invention
[0006] This application provides a novel use for zinc-based MOF materials. Specifically, this application provides the use of zinc-based MOF materials for adsorbing and / or separating C2 hydrocarbon gases or for fruit preservation.
[0007] In this application, zinc-based MOF materials refer to materials whose metal ions are Zn. 2+ Metal-organic framework materials.
[0008] This application provides the use of a zinc-based MOF material for adsorbing and / or separating C2 hydrocarbon gases. Furthermore, this application also provides the use of a zinc-based MOF material for fruit preservation.
[0009] In some embodiments, the pore size range of the zinc-based MOF material is [missing information]. For example etc.
[0010] In some embodiments, the BET specific surface area of the zinc-based MOF material is 500-600 m². 2 / g, for example 500m 2 / g、520m 2 / g、540m 2 / g、550m 2 / g、560m 2 / g、570m 2 / g、580m 2 / g、590m 2 / g、600m 2 / g etc.
[0011] In some embodiments, the pore volume of the zinc-based MOF material is 0.2-0.5 cm³. 3 / g, for example, 0.2cm 3 / g, 0.22cm 3 / g, 0.24cm 3 / g, 0.25cm 3 / g, 0.26cm 3 / g, 0.28cm 3 / g, 0.30cm 3 / g, 0.4cm 3 / g, 0.5cm 3 / g etc.
[0012] In some embodiments, the ligands of the zinc-based MOF material include vitamin C (ascorbic acid).
[0013] In some embodiments, the zinc-based MOF material has a three-dimensional structure.
[0014] In some embodiments, the zinc-based MOF material contains two types of channels, preferably with pore sizes of the two types of channels being respectively... and
[0015] In some embodiments, the apertures of the two types of channels are respectively and
[0016] In some embodiments, the zinc-based MOF material has the structural formula Zn3(ASC)(OH), where ASC represents vitamin C and OH represents hydroxyl groups.
[0017] In some embodiments, the zinc-based MOF material is used to preserve fruit. In some preferred embodiments, the fruit is a fruit that releases ethylene when ripe, such as a banana or mango.
[0018] In some embodiments, the zinc-based MOF material is used to adsorb and / or separate C2 hydrocarbon gases, which are selected from one or more of ethylene, ethane, and acetylene.
[0019] In some embodiments, the zinc-based MOF material is used to adsorb C2 hydrocarbon gases, which are selected from one or more of ethylene, ethane, or acetylene.
[0020] In some embodiments, the zinc-based MOF material is used to adsorb and separate C2 hydrocarbon gases, which include two or three of ethylene, ethane, and acetylene.
[0021] In some embodiments, the zinc-based MOF material is obtained by a preparation method comprising the following steps:
[0022] (1) Mix vitamin C, zinc salt, and optionally acetic acid in an alcohol solvent to form a mixture;
[0023] (2) The mixture obtained in step (1) is added to a high-pressure reactor for reaction. The reaction temperature is 100-140℃ and the reaction time is 24-96h.
[0024] In step (1) of the above preparation method, acetic acid can be added or not. Adding acetic acid can achieve a wider range of crystal sizes, thereby forming individual crystals with a size of up to 2 micrometers.
[0025] In some embodiments, the volume ratio of the alcohol solvent to acetic acid is 10:(0.5-1.5).
[0026] In some embodiments, in step (1), the zinc salt is zinc nitrate, zinc chloride, or zinc acetate.
[0027] In some embodiments, the molar ratio of the zinc salt to vitamin C is (2-2.5):1.
[0028] In some embodiments, the alcohol solvent is ethanol.
[0029] In some embodiments, in step (2), the reaction temperature is 110-120°C and the reaction time is 24-72h.
[0030] The above-mentioned green MOF material is obtained by solvothermal reaction of zinc metal salt and vitamin C. The material has stable structure and performance, good adsorption capacity for ethylene, and can preserve fruit at room temperature.
[0031] In some embodiments, the adsorption and / or separation temperature is -10°C to 30°C, and the adsorption and / or separation pressure is 10 to 1000 kPa.
[0032] In some embodiments, the adsorption and / or separation pressure is 10-1000 kPa, such as 10 kPa, 50 kPa, 100 kPa, 150 kPa, 200 kPa, 250 kPa, 300 kPa, 350 kPa, 400 kPa, 450 kPa, 100 kPa, 150 kPa, 200 kPa, 250 kPa, 300 kPa, 400 kPa, 500 kPa, 600 kPa, 700 kPa, 800 kPa, 900 kPa, or 1000 kPa, etc.
[0033] Compared with the prior art, the present invention has the following advantages and technical effects:
[0034] 1) The zinc-based MOF material used in this invention has a good adsorption capacity for ethylene, which can preserve fruit at room temperature.
[0035] 2) The zinc-based MOF material used in this invention has a high adsorption capacity for acetylene and ethane.
[0036] 3) The zinc-based MOF material used in this invention can achieve the separation of ethylene, acetylene and ethane. Attached Figure Description
[0037] Figure 1 This is a schematic diagram of the structure of ZnVc in Example 1.
[0038] Figure 2 The ethylene adsorption isotherms of ZnVc at two temperatures of 25°C and 0°C are shown in Example 1.
[0039] Figure 3 The ethane adsorption isotherms of ZnVc in Example 1 are shown at two temperatures: 25°C and 0°C.
[0040] Figure 4 The acetylene adsorption isotherms of ZnVc in Example 1 are shown at two temperatures: 25°C and 0°C.
[0041] Figure 5The adsorption isotherms of ZnVc at 25°C for acetylene, ethane, and ethylene are shown in Example 1.
[0042] Figure 6 The adsorption isotherms of ZnVc at 0°C for acetylene, ethane, and ethylene are shown in Example 1.
[0043] Figure 7 The dynamic penetration experiment of ZnVc in Example 1 at 25°C is shown. (Acetylene / ethane / ethylene / helium, 1 / 1 / 1 / 4, v / v / v / v, 2 ml / min) is shown.
[0044] Figure 8 The isotherm of water vapor adsorption of ZnVc at 25°C is shown in Example 1.
[0045] Figure 9 The experiment on the preservation of bananas by ZnVc at 25°C in Example 1 is shown.
[0046] Figure 10 The experiment shown in Example 1 illustrates the preservation control of bananas at 25°C without the preservative ZnVc. Detailed Implementation
[0047] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.
[0048] Example 1
[0049] 4.1 mmol zinc acetate, 1.7 mmol vitamin C, and 10 mL ethanol were mixed thoroughly, and 1 mL acetic acid was added. The mixture was placed in a 25 mL Teflon hydrothermal reactor and then placed in an oven at 120 °C for 24 hours. After the reaction was completed, the reactor was allowed to cool naturally. The resulting solid was washed several times with ethanol to obtain the purified product ZnVc. The purified product was then degassed under dynamic vacuum at 150 °C for 24 hours to obtain a solvent-free ZnVc adsorbent (i.e., the activated adsorbent), which was subsequently subjected to gas adsorption.
[0050] Figure 1 This is a schematic diagram of the structure of ZnVc prepared in this embodiment. Figure 1 It can be seen that ZnVc has two types of channels, and the pore sizes detected by the Horvath-Kawazoe method are respectively... and
[0051] Example 2
[0052] The adsorbent prepared in Example 1 was subjected to a gas adsorption test, and the results are as follows: Figure 2 , Figure 3 and Figure 4 As shown.
[0053] Figure 2 The adsorption isotherms of ZnVc adsorbent for ethylene at two temperatures are shown below. Figure 2 It can be seen that at 25℃, ZnVc has a high saturation adsorption capacity for ethylene, around 2.0 mmol / g, while at 0℃, the saturation adsorption capacity of ZnVc for ethylene is significantly increased, reaching around 2.87 mmol / g.
[0054] Figure 3 The adsorption isotherms of ZnVc adsorbent for ethane at two temperatures are shown below. Figure 3 It can be seen that at 25℃, ZnVc has a high saturation adsorption capacity for ethane, around 2.2 mmol / g, while at 0℃, the saturation adsorption capacity of ZnVc for ethane increases to around 2.95 mmol / g.
[0055] Figure 4 The adsorption isotherms of ZnVc adsorbent for acetylene at two temperatures are shown below. Figure 4 It can be seen that at 25℃, ZnVc has a high saturation adsorption capacity for acetylene, around 2.9 mmol / g, while at 0℃, the saturation adsorption capacity of ZnVc for acetylene increases to around 3.8 mmol / g.
[0056] Figure 5 and Figure 6 The adsorption isotherms of ZnVc adsorbent for acetylene, ethane, and ethylene at 25℃ and 0℃ are shown respectively. It can be clearly seen that ZnVc has a certain separation ability for the three components of acetylene / ethane / ethylene.
[0057] Example 3
[0058] To verify the actual separation effect of the ZnVc adsorbent prepared in Example 1 on C2 hydrocarbon gases, a breakthrough experiment was conducted using 1.626 g of the ZnVc adsorbent synthesized in Example 1 to test a C2 hydrocarbon gas mixture. Specifically, a mixture of acetylene, ethane, ethylene, and helium was prepared in a volume ratio of 1 / 1 / 1 / 4, and the breakthrough experiment was performed at a breakthrough temperature of 25°C, a pressure of 0.1 MPa, and a gas flow rate of 2 mL / min.
[0059] See dynamic penetration curve Figure 7 .from Figure 7 It can be seen that acetylene, ethane, and ethylene penetrated at 13 min, 19 min, and 35 min, respectively.
[0060] At 25℃, the ZnVc adsorbent can separate acetylene / ethane / ethylene, and can achieve one-step separation to obtain ethylene.
[0061] Example 4
[0062] The ZnVc adsorbent prepared in Example 1 was subjected to water vapor adsorption, and the results are as follows: Figure 8 As shown, ads represents adsorption and des represents desorption.
[0063] Figure 8 The isotherm of water vapor adsorption of ZnVc at 25℃ is shown below. Figure 8 It can be seen that at 25℃, ZnVc has a high saturation adsorption capacity for water vapor, with an adsorption capacity of about 10.0 mmol / g. This indicates that ZnVc has a certain drying effect while preserving fruit, which is more conducive to fruit preservation.
[0064] Example 5
[0065] The ZnVc adsorbent prepared in Example 1 was used in a fruit preservation test. In this example, both the adsorbent group and the blank control group used freshly purchased bananas.
[0066] Adsorbent group: 0.6g of ZnVc adsorbent prepared according to Example 1 and fresh bananas were placed in a sealed transparent glass jar and stored at 25°C for 15 days. Photos were taken daily. Figure 9 This is a compilation of photos from 15 days.
[0067] Blank control group: Fresh bananas were placed in a sealed, transparent glass jar and stored at 25°C for 15 days. The only difference from the adsorbent group was that no ZnVc adsorbent was added. Figure 10 A compilation of photos of the blank control group stored at 25℃ for 15 days.
[0068] contrast Figure 9 and Figure 10 It can be clearly observed that after 15 days of storage, the bananas with ZnVc adsorbent only have a few spots, while the bananas in the blank control group have large areas of spots and are rotten and black.
Claims
1. The use of a zinc-based MOF material for adsorbing and / or separating C2 hydrocarbon gases or for fruit preservation.
2. The use according to claim 1, characterized in that, The zinc-based MOF material contains zinc ions as the metal ion, vitamin C as the ligand, and / or the pore size range of the zinc-based MOF material is [missing information]. And / or the BET specific surface area of the zinc-based MOF material is 500-600 m². 2 / g; and / or the pore volume of the zinc-based MOF material is 0.2-0.5 cm³. 3 / g.
3. The use according to claim 1, characterized in that, The zinc-based MOF material has the structural formula Zn3(ASC)(OH), where ASC is vitamin C. The zinc-based MOF material has a three-dimensional structure containing two types of channels. Preferably, the pore sizes of the two types of channels are... and 4. The use according to claim 1, characterized in that, The zinc-based MOF material is used for fruit preservation, and preferably, the fruit is a banana.
5. The use according to claim 1, characterized in that, The zinc-based MOF material is used to adsorb and / or separate C2 hydrocarbon gases, which are selected from one or more of ethylene, ethane, and acetylene.
6. The use according to claim 1, characterized in that, The zinc-based MOF material is used to adsorb C2 hydrocarbon gases, wherein the C2 hydrocarbon gases are selected from one or more of ethylene, ethane, or acetylene; The zinc-based MOF material is used to adsorb and separate C2 hydrocarbon gases, which include two or three of ethylene, ethane, and acetylene.
7. The use according to claim 1, characterized in that, The zinc-based MOF material is obtained by a preparation method including the following steps: (1) Mix vitamin C, zinc salt, and optionally acetic acid in an alcohol solvent to form a mixture; (2) The mixture obtained in step (1) is added to a high-pressure reactor for reaction. The reaction temperature is 100-140℃ and the reaction time is 24-96h.
8. The use according to claim 7, characterized in that, In step (1), the zinc salt is zinc nitrate, zinc chloride, or zinc acetate; the molar ratio of the zinc salt to vitamin C is (2-2.5):1; the volume ratio of the alcohol solvent to acetic acid is 10:(0.5-1.5); and the alcohol solvent is ethanol.
9. The use according to claim 7 or 8, characterized in that, In step (2), the reaction temperature is 110-120℃ and the reaction time is 24-72h.
10. The use according to any one of claims 1-9, characterized in that, The adsorption temperature is -10℃ to 30℃, and the adsorption pressure is 10 to 1000 kPa.