Non-ferrous efficient deoxidizer and preparation method thereof

Abstract

The invention provides a non-ferrous efficient deoxidizer and a preparation method thereof, the non-ferrous efficient deoxidizer comprises a carbon nanosphere / porous diatomite compound, and ascorbic acid and sodium chloride are loaded on the carbon nanosphere / porous diatomite compound; the nano carbon sphere / porous diatomite compound comprises porous diatomite and nano carbon spheres loaded on the porous diatomite. According to the deoxidizer, the nano carbon sphere / porous diatomite compound serves as a carrier, ascorbic acid and sodium chloride serve as main deoxidizer effective components, and the prepared non-ferrous efficient deoxidizer is high in deoxidization efficiency and high in stability.

Description

Technical Field

[0001] The present invention relates to the technical field of deoxidizers, and particularly relates to a non-ferrous high-efficiency deoxidizer and a preparation method thereof. Background Art

[0002] Oxidation deterioration is one of the factors causing the deterioration of packaged foods. The main reason is that oxygen and moisture become the breeding ground for microorganisms, and the presence of oxygen also promotes reactions such as enzymatic browning of foods, lipid oxidation, and protein denaturation. Therefore, for packaged foods, it is necessary to effectively reduce their oxygen content to avoid the occurrence of food oxidation deterioration.

[0003] Currently, the food industry generally uses packaging methods such as gas replacement packaging and vacuum packaging to remove most of the oxygen in the package, but generally there is still 2% - 3% of oxygen that cannot be removed. The presence of this oxygen still has a greater impact on oxygen-sensitive foods. Therefore, it is still necessary to effectively remove the residual oxygen in the package.

[0004] Among them, food deoxidizers can absorb the oxygen in the package and are usually placed in food packages in the form of small bags to ensure that the oxygen in the sealed environment is continuously absorbed. Deoxidizers generally have the characteristics of high efficiency, safety, and environmental protection, will not contaminate foods, and are easy to handle after use. Among them, iron powder is a commonly used deoxidizer, but its reaction rate with oxygen is greatly affected by environmental humidity, and the reaction is slow in a dry environment. Moreover, if the deoxidizer package is damaged, the iron powder may still directly contact the food, causing contamination and affecting the safety and taste of the food. Ascorbic acid, as a natural deoxidizer, has higher safety performance compared to iron powder, so it is often used as the main deoxidizer for some foods. When using ascorbic acid as a deoxidizer for nuts, snacks, baking and other foods, it is necessary to use a carrier such as a porous material to load ascorbic acid. However, currently, after the porous material loads ascorbic acid, the deoxidation performance of the obtained deoxidizer is generally low. Therefore, it is necessary to research and develop a supported ascorbic acid deoxidizer to improve its deoxidation performance in packaged foods. Summary of the Invention

[0005] The present invention provides a non-ferrous high-efficiency deoxidizer and a preparation method thereof. The deoxidizer uses a nano-carbon sphere / porous diatomaceous earth composite as a carrier, and ascorbic acid and sodium chloride as the main deoxidizer active ingredients. The prepared non-ferrous high-efficiency deoxidizer has high deoxidation efficiency and strong stability.

[0006] To achieve the above objectives, the present invention is realized through the following technical solutions: A non-ferrous high-efficiency deoxidizer, the non-ferrous high-efficiency deoxidizer includes a nano-carbon sphere / porous diatomite composite, and ascorbic acid and sodium chloride are loaded on the nano-carbon sphere / porous diatomite composite; the nano-carbon sphere / porous diatomite composite includes porous diatomite and nano-carbon spheres loaded on the porous diatomite.

[0007] Preferably, the mass ratio of ascorbic acid to sodium chloride is 8.5~12.5:1.5~2.5.

[0008] Preferably, the preparation method of the porous diatomite includes the following steps: 1) Add 25~35 parts of diatomite powder, 10~15 parts of starch, 5~10 parts of silica sol, 1~2 parts of sodium alginate, and 0.3~1 part of polyethylene glycol to 100 parts of water, and then carry out ball milling to obtain a mixture; 2) Place the mixture in a polytetrafluoroethylene mold with a copper plate at the bottom, freeze it into a block at -40~-30°C, and then place the polytetrafluoroethylene mold in a vacuum freeze dryer for vacuum freeze drying; 3) Take out the product obtained by vacuum freeze drying from the polytetrafluoroethylene mold, and then carry out roasting; then naturally cool to room temperature, crush and pass through a 30-mesh sieve to obtain the porous diatomite.

[0009] Preferably, in step 1), the particle size of the diatomite powder is 240~300 mesh; the particle size of the starch is 40~60μm; the modulus of the silica sol is 2.8~3.5; the polyethylene glycol is at least one of polyethylene glycol 2000 and polyethylene glycol 4000.

[0010] Preferably, in step 3), heat up to 240~300°C at a heating rate of 6~10°C / min, hold for 1~1.5h, and then heat up to 880~920°C at a heating rate of 10~15°C / min, and hold for 2~3h.

[0011] Preferably, the preparation method of the nano-carbon sphere / porous diatomite composite includes the following steps: Place the porous diatomite in an aqueous glucose solution, let it stand and then carry out a hydrothermal reaction, and then cool to room temperature, filter, wash with water, and dry to obtain the nano-carbon sphere / porous diatomite composite.

[0012] Preferably, in the aqueous glucose solution, the mass fraction of glucose is 10~15%; the mass-volume ratio of the aqueous glucose solution to the porous diatomite is 25~40mL:1g.

[0013] Preferably, the standing time is 2~3h, and the temperature is 40~50°C; the temperature of the hydrothermal reaction is 200~210°C, and the time of the hydrothermal reaction is 6~10h.

[0014] As a general inventive concept, the present invention also provides a method for preparing a non-ferrous high-efficiency deoxidizer, comprising the following steps: Under a nitrogen atmosphere and in the dark, the nano-carbon sphere / porous diatomite composite is impregnated in a deoxidizer aqueous mixture, and the deoxidizer aqueous mixture comprises the following raw materials in weight percentages: ascorbic acid 8.5-12.5%, sodium chloride 1.5-2.5%, and the balance being water; then centrifugal separation is carried out under a nitrogen atmosphere and in the dark to obtain a precipitate; and then the obtained precipitate is subjected to vacuum freeze-drying in the dark to obtain the non-ferrous high-efficiency deoxidizer. When preparing the deoxidizer aqueous mixture of the present invention, ascorbic acid and sodium chloride are added to water under a nitrogen atmosphere and in the dark. After stirring and mixing, it is obtained.

[0015] Preferably, the time for impregnating the nano-carbon sphere / porous diatomite composite in the deoxidizer aqueous mixture is 2.5-4.5 h, and the temperature is 20-30 °C.

[0016] The beneficial effects of the present invention are as follows: 1. In the non-ferrous high-efficiency deoxidizer of the present invention, ascorbic acid is used as the main active ingredient of the deoxidizer, and the combined sodium chloride can make ascorbic acid react with oxygen more effectively; ascorbic acid has high safety performance as a food deoxidizer, but its deoxidizing ability is relatively weak. To further improve its deoxidizing efficiency, the present invention uses a nano-carbon sphere / porous diatomite composite as a carrier, which has many pores and a stable structure, can effectively load and fix ascorbic acid, and can make ascorbic acid efficiently exert its deoxidizing performance, and can prevent it from caking, effectively improving the usability and safety performance of the deoxidizer.

[0017] 2. The nano-carbon sphere / porous diatomite composite of the present invention comprises porous diatomite and nano-carbon spheres loaded on the porous diatomite. By loading nano-carbon spheres on the porous diatomite, the nano-carbon spheres can provide more active sites, enhance the redox reaction activity of ascorbic acid, and thus improve its deoxidation efficiency. The nano-carbon spheres have certain pores, which can load a part of ascorbic acid and sodium chloride, and increase the roughness and loading capacity of the internal pores of the porous diatomite, can improve the binding degree of ascorbic acid, sodium chloride and the internal pores of the porous diatomite, strengthen the stability of the non-ferrous high-efficiency deoxidizer, and can promote the deoxidizing performance of the active ingredients of the deoxidizer.

[0018] 3. When preparing porous diatomite in the present invention, starch is used as the main pore-forming agent, and on this basis, it is combined with sodium alginate and polyethylene glycol. Combining with the subsequent preparation process, the obtained porous diatomite can be rich in pores. The addition of an appropriate amount of silica sol can effectively improve the strength of the porous diatomite and endow it with higher structural stability. During the preparation process of the porous diatomite in the present invention, the mixture containing diatomite powder, pore-forming agent, etc. is frozen using a polytetrafluoroethylene mold, and then vacuum-dried and calcined. Compared with direct calcination, the pores in the porous diatomite can be made more abundant, the loading capacity can be stronger, and the deoxidation performance of the obtained deoxidizer can be significantly improved.

[0019] After the porous diatomite of the present invention is loaded with rice carbon balls, it still has abundant pores. Moreover, after being loaded with ascorbic acid and sodium chloride, it can still maintain a high porosity, so that the oxygen in the packaging environment can easily enter the pores and be consumed by ascorbic acid. In this way, the deoxidation performance of the non-ferrous deoxidizer of the present invention can be further improved. Specific Embodiments

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0021] Example 1: A non-ferrous high-efficiency deoxidizer includes a nano-carbon ball / porous diatomite composite, and ascorbic acid and sodium chloride are loaded on the nano-carbon ball / porous diatomite composite; the nano-carbon ball / porous diatomite composite includes porous diatomite and nano-carbon balls loaded on the porous diatomite.

[0022] The preparation method of the porous diatomite in this example includes the following steps: 1) Add 30 parts of diatomite powder, 10 parts of starch, 8 parts of silica sol, 1.5 parts of sodium alginate, and 0.6 part of polyethylene glycol 2000 to 100 parts of water, and then carry out ball milling to obtain a mixture; the particle size of the diatomite powder is 240 - 300 mesh; the particle size of the starch is 40 - 60 μm; the modulus of the silica sol is 3.2.

[0023] 2) Place the mixture in a polytetrafluoroethylene mold with a copper plate at the bottom, freeze it into a block at -40°C, and then place the polytetrafluoroethylene mold in a vacuum freeze dryer for vacuum freeze drying.

[0024] 3) Take out the product obtained by vacuum freeze-drying from the polytetrafluoroethylene mold, and then conduct calcination. During calcination, first heat it up to 240 °C at a heating rate of 6 °C / min, hold for 1 h, then heat it up to 880 °C at a heating rate of 12 °C / min, and hold for 3 h; then naturally cool it to room temperature, crush it, and pass through a 30-mesh sieve to obtain porous diatomite.

[0025] The preparation method of the nano-carbon sphere / porous diatomite composite in this example includes the following steps: Place the porous diatomite in an aqueous glucose solution with a mass fraction of 13%, and the mass-volume ratio of the aqueous glucose solution to the porous diatomite is 30 mL:1 g; let it stand for 2 h, and the standing temperature is 50 °C; then conduct a hydrothermal reaction, the temperature of the hydrothermal reaction is 210 °C, and the time of the hydrothermal reaction is 8 h; then cool it to room temperature, filter, wash with water, and dry to obtain the nano-carbon sphere / porous diatomite composite.

[0026] The preparation method of the non-ferrous high-efficiency deoxidizer in this example includes the following steps: Under a nitrogen atmosphere and in the dark, immerse the nano-carbon sphere / porous diatomite composite in the deoxidizer aqueous mixture for 4.5 h, and the immersion temperature is 30 °C. The deoxidizer aqueous mixture includes the following raw materials in weight percentages: ascorbic acid 9.5%, sodium chloride 1.5%, and the balance is water; Then centrifuge and separate to obtain a precipitate under a nitrogen atmosphere and in the dark; then conduct vacuum freeze-drying on the obtained precipitate in the dark to obtain the non-ferrous high-efficiency deoxidizer.

[0027] Example 2: A non-ferrous high-efficiency deoxidizer includes a nano-carbon sphere / porous diatomite composite, and ascorbic acid and sodium chloride are loaded on the nano-carbon sphere / porous diatomite composite; the nano-carbon sphere / porous diatomite composite includes porous diatomite and nano-carbon spheres loaded on the porous diatomite.

[0028] The preparation method of the porous diatomite in this example includes the following steps: 1) Add 25 parts of diatomite powder, 10 parts of starch, 5 parts of silica sol, 2 parts of sodium alginate, and 0.3 part of polyethylene glycol 2000 to 100 parts of water, and then conduct ball milling to obtain a mixture; the particle size of the diatomite powder is 240 - 300 mesh; the particle size of the starch is 40 - 60 μm; the modulus of the silica sol is 3.5.

[0029] 2) Place the mixture in a polytetrafluoroethylene mold with a copper plate at the bottom, freeze it into a block at -40 °C, and then place the polytetrafluoroethylene mold in a vacuum freeze dryer for vacuum freeze-drying.

[0030] 3) Take out the product obtained by vacuum freeze-drying from the polytetrafluoroethylene mold, and then conduct calcination. During calcination, first heat it at a heating rate of 10 °C / min to 300 °C, hold for 1 h, then heat it at a heating rate of 10 °C / min to 920 °C, and hold for 2 h; then cool it naturally to room temperature, pulverize it, and pass through a 30-mesh sieve to obtain porous diatomite.

[0031] The preparation method of the nano-carbon sphere / porous diatomite composite in this example includes the following steps: Place the porous diatomite in a glucose aqueous solution with a mass fraction of 15%, and the mass-volume ratio of the glucose aqueous solution to the porous diatomite is 40 mL:1 g; let it stand for 3 h, and the standing temperature is 40 °C; then conduct a hydrothermal reaction, the temperature of the hydrothermal reaction is 205 °C, and the time of the hydrothermal reaction is 10 h; then cool it to room temperature, and obtain the nano-carbon sphere / porous diatomite composite through filtration, washing, and drying.

[0032] The preparation method of the non-ferrous high-efficiency deoxidizer in this example includes the following steps: Under a nitrogen atmosphere and in the dark, immerse the nano-carbon sphere / porous diatomite composite in the deoxidizer aqueous mixture for 4 h, and the immersion temperature is 30 °C. The deoxidizer aqueous mixture includes the following raw materials in weight percentages: ascorbic acid 12.5%, sodium chloride 2%, and the balance is water; Then centrifuge and separate to obtain a precipitate under a nitrogen atmosphere and in the dark; then conduct vacuum freeze-drying on the obtained precipitate in the dark to obtain the non-ferrous high-efficiency deoxidizer.

[0033] Example 3: A non-ferrous high-efficiency deoxidizer includes a nano-carbon sphere / porous diatomite composite, and ascorbic acid and sodium chloride are loaded on the nano-carbon sphere / porous diatomite composite; the nano-carbon sphere / porous diatomite composite includes porous diatomite and nano-carbon spheres loaded on the porous diatomite.

[0034] The preparation method of the porous diatomite in this example includes the following steps: 1) Add 35 parts of diatomite powder, 15 parts of starch, 10 parts of silica sol, 1 part of sodium alginate, and 1 part of polyethylene glycol 2000 to 100 parts of water, and then conduct ball milling to obtain a mixed material; the particle size of the diatomite powder is 240 - 300 mesh; the particle size of the starch is 40 - 60 μm; the modulus of the silica sol is 2.8.

[0035] 2) Place the mixed material in a polytetrafluoroethylene mold with a copper plate at the bottom, freeze it into a block at -30 °C, and then place the polytetrafluoroethylene mold in a vacuum freeze-dryer for vacuum freeze-drying.

[0036] 3) Take out the product obtained by vacuum freeze-drying from the polytetrafluoroethylene mold, and then conduct calcination. During calcination, first heat up to 280 °C at a heating rate of 6 °C / min, hold for 1.5 h, then heat up to 900 °C at a heating rate of 15 °C / min, and hold for 2 h; then naturally cool to room temperature, pulverize, and pass through a 30-mesh sieve to obtain porous diatomite.

[0037] The preparation method of the nano-carbon sphere / porous diatomite composite in this example includes the following steps: Place the porous diatomite in an aqueous glucose solution with a mass fraction of 12.3%, and the mass-volume ratio of the aqueous glucose solution to the porous diatomite is 25 mL:1 g; let it stand for 3 h, and the standing temperature is 45 °C; then carry out a hydrothermal reaction, the temperature of the hydrothermal reaction is 200 °C, and the time of the hydrothermal reaction is 6 h; then cool to room temperature, filter, wash with water, and dry to obtain the nano-carbon sphere / porous diatomite composite.

[0038] The preparation method of the non-ferrous high-efficiency deoxidizer in this example includes the following steps: Under a nitrogen atmosphere and in the dark, immerse the nano-carbon sphere / porous diatomite composite in the deoxidizer aqueous mixture for 2.5 h, and the immersion temperature is 30 °C. The deoxidizer aqueous mixture includes the following raw materials in weight percentages: ascorbic acid 11%, sodium chloride 2.5%, and the balance is water; Then centrifuge and separate to obtain a precipitate under a nitrogen atmosphere and in the dark; then carry out vacuum freeze-drying on the obtained precipitate in the dark to obtain the non-ferrous high-efficiency deoxidizer.

[0039] Example 4: A non-ferrous high-efficiency deoxidizer includes a nano-carbon sphere / porous diatomite composite, and ascorbic acid and sodium chloride are loaded on the nano-carbon sphere / porous diatomite composite; the nano-carbon sphere / porous diatomite composite includes porous diatomite and nano-carbon spheres loaded on the porous diatomite.

[0040] The preparation method of the porous diatomite in this example includes the following steps: 1) Add 32 parts of diatomite powder, 13 parts of starch, 8 parts of silica sol, 1 part of sodium alginate, and 0.5 part of polyethylene glycol 2000 to 100 parts of water, and then carry out ball milling to obtain a mixture; the particle size of the diatomite powder is 240 - 300 mesh; the particle size of the starch is 40 - 60 μm; the modulus of the silica sol is 2.8.

[0041] 2) Place the mixture in a polytetrafluoroethylene mold with a copper plate at the bottom, freeze it into a block at -40 °C, and then place the polytetrafluoroethylene mold in a vacuum freeze dryer for vacuum freeze-drying; 3) Take out the product obtained by vacuum freeze-drying from the polytetrafluoroethylene mold, and then conduct calcination. During calcination, first heat it up to 240 °C at a heating rate of 6 °C / min, hold for 1.5 h, then heat it up to 880 °C at a heating rate of 12 °C / min, and hold for 3 h; then cool it naturally to room temperature, crush it, and pass through a 30-mesh sieve to obtain porous diatomite.

[0042] The preparation method of the nano-carbon sphere / porous diatomite composite in this example includes the following steps: Place the porous diatomite in a 10% glucose aqueous solution, and the mass-volume ratio of the glucose aqueous solution to the porous diatomite is 28 mL:1 g; let it stand for 3 h, and the standing temperature is 50 °C; then conduct a hydrothermal reaction, the temperature of the hydrothermal reaction is 210 °C, and the time of the hydrothermal reaction is 8 h; then cool it to room temperature, filter, wash with water, and dry to obtain the nano-carbon sphere / porous diatomite composite.

[0043] The preparation method of the non-ferrous high-efficiency deoxidizer in this example includes the following steps: Under a nitrogen atmosphere and in the dark, immerse the nano-carbon sphere / porous diatomite composite in the deoxidizer aqueous mixture for 3 h, and the immersion temperature is 25 °C. The deoxidizer aqueous mixture includes the following raw materials in weight percentages: ascorbic acid 8.5%, sodium chloride 1.8%, and the balance is water; Then centrifuge and separate to obtain a precipitate under a nitrogen atmosphere and in the dark; then conduct vacuum freeze-drying on the obtained precipitate in the dark to obtain the non-ferrous high-efficiency deoxidizer.

[0044] Comparative Example 1: The main difference from Example 4 is that the used nano-carbon sphere / porous diatomite composite is replaced with porous diatomite.

[0045] Specifically, a deoxidizer includes porous diatomite, and ascorbic acid and sodium chloride are loaded on the porous diatomite.

[0046] The preparation method of the porous diatomite in this comparative example includes the following steps: 1) Add 32 parts of diatomite powder, 13 parts of starch, 8 parts of silica sol, 1 part of sodium alginate, and 0.5 part of polyethylene glycol 2000 to 100 parts of water, and then conduct ball milling to obtain a mixture; the particle size of the diatomite powder is 240 - 300 mesh; the particle size of the starch is 40 - 60 μm; the modulus of the silica sol is 2.8.

[0047] 2) Place the mixture in a polytetrafluoroethylene mold with a copper plate bottom, freeze it into a block at -40 °C, and then place the polytetrafluoroethylene mold in a vacuum freeze-dryer for vacuum freeze-drying; 3) Take out the product obtained by vacuum freeze-drying from the polytetrafluoroethylene mold, and then conduct roasting. During roasting, first raise the temperature to 240°C at a heating rate of 6°C / min, hold for 1.5 h, then raise the temperature to 880°C at a heating rate of 12°C / min, and hold for 3 h; then naturally cool to room temperature, pulverize, and pass through a 30-mesh sieve to obtain porous diatomite.

[0048] The preparation method of the non-ferrous series high-efficiency deoxidizer in this comparative example includes the following steps: Under a nitrogen atmosphere and in the dark, immerse the porous diatomite in the deoxidizer aqueous mixture for 3 h, and the immersion temperature is 25°C. The deoxidizer aqueous mixture includes the following raw materials by weight percentage: ascorbic acid 8.5%, sodium chloride 1.8%, and the balance is water; Then, centrifuge and separate to obtain a precipitate under a nitrogen atmosphere and in the dark; then conduct vacuum freeze-drying on the obtained precipitate in the dark to obtain a deoxidizer.

[0049] Comparative Example 2: The main difference from Example 4 is that the method steps for preparing the porous diatomite are different.

[0050] Specifically, a deoxidizer includes a nano-carbon sphere / porous diatomite composite, and ascorbic acid and sodium chloride are loaded on the nano-carbon sphere / porous diatomite composite; the nano-carbon sphere / porous diatomite composite includes porous diatomite and nano-carbon spheres loaded on the porous diatomite.

[0051] The preparation method of the porous diatomite in this comparative example includes the following steps: 1) Add 32 parts of diatomite powder, 13 parts of starch, 8 parts of silica sol, 1 part of sodium alginate, and 0.5 part of polyethylene glycol 2000 to 100 parts of water, and then conduct ball milling to obtain a mixed material; wherein the particle size of the diatomite powder is 240 - 300 mesh; the particle size of the starch is 40 - 60 μm; the modulus of the silica sol is 2.8.

[0052] 2) Conduct vacuum drying on the mixed material, and then conduct roasting. During roasting, first raise the temperature to 240°C at a heating rate of 6°C / min, hold for 1.5 h, then raise the temperature to 880°C at a heating rate of 12°C / min, and hold for 3 h; then naturally cool to room temperature, pulverize, and pass through a 30-mesh sieve to obtain porous diatomite.

[0053] The preparation method of the nano-carbon sphere / porous diatomite composite in this comparative example comprises the following steps: placing the porous diatomite in an aqueous glucose solution with a mass fraction of 13%, and the mass-volume ratio of the aqueous glucose solution to the porous diatomite is 28 mL:1 g; standing for 3 h at a standing temperature of 50 °C; then carrying out a hydrothermal reaction at a hydrothermal reaction temperature of 210 °C for 8 h; then cooling to room temperature, filtering, washing with water, and drying to obtain the nano-carbon sphere / porous diatomite composite.

[0054] The preparation method of the deoxidizer in this comparative example comprises the following steps: Under a nitrogen atmosphere and in the dark, impregnating the nano-carbon sphere / porous diatomite composite in a deoxidizer aqueous mixture for 3 h at an impregnation temperature of 25 °C, and the deoxidizer aqueous mixture comprises the following raw materials in weight percentages: ascorbic acid 8.5%, sodium chloride 1.8%, and the balance is water; Then centrifuging and separating under a nitrogen atmosphere and in the dark to obtain a precipitate; then carrying out vacuum freeze-drying on the obtained precipitate in the dark to obtain the deoxidizer.

[0055] Comparative Example 3: Differing from Example 4, the raw materials for preparing the porous diatomite are different.

[0056] Specifically, a deoxidizer comprises a nano-carbon sphere / porous diatomite composite, and ascorbic acid and sodium chloride are loaded on the nano-carbon sphere / porous diatomite composite; the nano-carbon sphere / porous diatomite composite comprises porous diatomite and nano-carbon spheres loaded on the porous diatomite.

[0057] The preparation method of the porous diatomite in this comparative example comprises the following steps: 1) Adding 32 parts of diatomite powder, 13 parts of starch, and 8 parts of silica sol to 100 parts of water, and then carrying out ball milling to obtain a mixture; wherein the particle size of the diatomite powder is 240 - 300 mesh; the particle size of the starch is 40 - 60 μm; the modulus of the silica sol is 2.8.

[0058] 2) Placing the mixture in a polytetrafluoroethylene mold with a copper plate bottom, freezing it into a block at -40 °C, and then placing the polytetrafluoroethylene mold in a vacuum freeze dryer for vacuum freeze-drying; 3) Taking out the product obtained by vacuum freeze-drying from the polytetrafluoroethylene mold, and then carrying out roasting. During roasting, first heating it at a heating rate of 6 °C / min to 240 °C, holding for 1.5 h, then heating it at a heating rate of 12 °C / min to 880 °C, holding for 3 h; then naturally cooling to room temperature, pulverizing, and sieving through a 30-mesh sieve to obtain the porous diatomite.

[0059] The preparation method of the nano-carbon sphere / porous diatomite composite in this comparative example includes the following steps: placing the porous diatomite in an aqueous glucose solution with a mass fraction of 13%, and the mass-volume ratio of the aqueous glucose solution to the porous diatomite is 28 mL:1 g; standing for 3 h at a standing temperature of 50 °C; then carrying out a hydrothermal reaction at a hydrothermal reaction temperature of 210 °C for 8 h; then cooling to room temperature, filtering, washing with water, and drying to obtain the nano-carbon sphere / porous diatomite composite.

[0060] The preparation method of the deoxidizer in this comparative example includes the following steps: Under a nitrogen atmosphere and in the dark, impregnate the nano-carbon sphere / porous diatomite composite in the deoxidizer aqueous mixture for 3 h at an impregnation temperature of 25 °C. The deoxidizer aqueous mixture includes the following raw materials by weight percentage: ascorbic acid 8.5%, sodium chloride 1.8%, and the balance is water; Then, centrifuge and separate to obtain a precipitate under a nitrogen atmosphere and in the dark; then carry out vacuum freeze-drying on the obtained precipitate in the dark to obtain the deoxidizer.

[0061] Comparative Example 4: Different from Example 4, the nano-carbon sphere / porous diatomite composite is replaced with conventional diatomite.

[0062] Specifically, a deoxidizer includes diatomite, and ascorbic acid and sodium chloride are loaded on the diatomite.

[0063] The preparation method of the deoxidizer in this comparative example includes the following steps: Under a nitrogen atmosphere and in the dark, place the diatomite in the deoxidizer aqueous mixture and impregnate for 3 h at an impregnation temperature of 25 °C. The deoxidizer aqueous mixture includes the following raw materials by weight percentage: ascorbic acid 8.5%, sodium chloride 1.8%, and the balance is water; Then, centrifuge and separate to obtain a precipitate under a nitrogen atmosphere and in the dark; then carry out vacuum freeze-drying on the obtained precipitate in the dark to obtain the deoxidizer.

[0064] Performance test: Pack the deoxidizers prepared in Examples 1 to 4 and Comparative Examples 1 to 4 with deoxidizer packaging bags, and then place them in food packaging bags. The placement amount of the deoxidizer is 1.3% of the food quality. Then place the food packaging bags at 25 - 28 °C for 2 days and test the oxygen absorption rate. Then continue to store at 25 - 28 °C for 3 months and test the food moisture regain rate. The specific oxygen absorption rate and food moisture regain rate are shown in Table 1.

[0065] Table 1 Test results of oxygen absorption rate and food moisture regain rate From the oxygen absorption rate and food moisture regain rate test results in Table 1, it can be seen that the oxygen scavenger in the examples has excellent oxygen absorption rate and low food moisture regain rate.

[0066] From the comparison between Comparative Example 1 and Example 4, it can be seen that if the nano-carbon spheres are not loaded on the porous diatomite and only the porous diatomite is used as the carrier, the oxygen absorption rate will be significantly reduced.

[0067] From the comparison between Comparative Example 2 and Example 4, it can be seen that if the "freezing-vacuum freeze-drying" method is not combined during the preparation of the porous diatomite, the oxygen absorption rate will decrease significantly and the food moisture regain rate will also increase.

[0068] From the comparison between Comparative Example 3 and Example 4, it can be seen that if sodium alginate and polyethylene glycol are not added during the preparation of the porous diatomite, its oxygen absorption rate will decrease.

[0069] From the comparison between Comparative Example 3 and Example 4, it can be seen that if the carrier nano-carbon sphere / porous diatomite composite is replaced with conventional diatomite, the oxygen absorption rate will decrease significantly and the food moisture regain rate will also increase significantly.

[0070] The above examples are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing examples, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing examples, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A non-iron high-efficiency deoxidizer, characterized in that: The non-iron-based high-efficiency deoxidizer comprises a nano-carbon ball / porous diatomite composite, on which ascorbic acid and sodium chloride are loaded; the nano-carbon ball / porous diatomite composite comprises porous diatomite and nano-carbon balls loaded on the porous diatomite.

2. The non-iron-based high-efficiency deoxidizer according to claim 1, characterized in that: The mass ratio of ascorbic acid to sodium chloride is 8.5-12.5:1.5-2.

5.

3. The non-iron-based high-efficiency deoxidizer according to claim 1, characterized in that: The preparation method of the porous diatomite comprises the following steps: 1) Add 25-35 parts of diatomaceous earth powder, 10-15 parts of starch, 5-10 parts of silica sol, 1-2 parts of sodium alginate, and 0.3-1 part of polyethylene glycol to 100 parts of water, and then ball-mill to obtain a mixture; 2) placing the mixture in a polytetrafluoroethylene mold with a copper plate at the bottom, freezing it at -40 to -30°C to form a block, and then placing the polytetrafluoroethylene mold in a vacuum freeze dryer for vacuum freeze drying; 3) The product obtained by vacuum freeze drying is taken out from the polytetrafluoroethylene mold, and then roasted; then naturally cooled to room temperature, crushed, and passed through a 30-mesh sieve to obtain the porous diatomaceous earth.

4. The non-iron-based high-efficiency deoxidizer according to claim 3, characterized in that: In step 1), the particle size of the diatomaceous earth powder is 240-300 mesh; the particle size of the starch is 40-60 μm; the modulus of the silica sol is 2.8-3.5; and the polyethylene glycol is at least one of polyethylene glycol 2000 and polyethylene glycol 4000.

5. The non-iron-based high-efficiency deoxidizer according to claim 3, characterized in that: In step 3), the temperature is increased to 240-300°C at a heating rate of 6-10°C / min, and kept at this temperature for 1-1.5 hours. Then, the temperature is increased to 880-920°C at a heating rate of 10-15°C / min, and kept at this temperature for 2-3 hours.

6. The non-iron-based high-efficiency deoxidizer according to claim 1, characterized in that: The preparation method of the nano carbon ball / porous diatomite composite comprises the following steps: placing the porous diatomite in a glucose aqueous solution, allowing it to stand for hydrothermal reaction, cooling it to room temperature, filtering, washing with water, and drying to obtain the nano carbon ball / porous diatomite composite.

7. The non-iron-based high-efficiency deoxidizer according to claim 6, characterized in that: In the glucose aqueous solution, the mass fraction of glucose is 10-15%; the mass volume ratio of the glucose aqueous solution to the porous diatomaceous earth is 25-40 mL: 1 g.

8. The non-iron-based high-efficiency deoxidizer according to claim 6, characterized in that: The standing time is 2-3 hours, and the temperature is 40-50° C.; the temperature of the hydrothermal reaction is 200-210° C., and the time of the hydrothermal reaction is 6-10 hours.

9. A method for preparing a non-iron-based high-efficiency deoxidizer as claimed in any one of claims 1 to 8, characterized in that: The following steps are involved: In a nitrogen atmosphere and under light-proof conditions, the nano-carbon ball / porous diatomite composite is immersed in a deoxidizer water mixture, wherein the deoxidizer water mixture comprises the following raw materials in weight percentage: 8.5-12.5% ​​ascorbic acid, 1.5-2.5% sodium chloride, and the balance water; then centrifugation is performed in a nitrogen atmosphere and under light-proof conditions to obtain a precipitate; and then the obtained precipitate is vacuum freeze-dried under light-proof conditions to obtain the non-iron-based high-efficiency deoxidizer.

10. The method for preparing the non-iron-based high-efficiency deoxidizer according to claim 9, characterized in that: The nano carbon sphere / porous diatomaceous earth composite is immersed in the deoxidizer water mixture for 2.5 to 4.5 hours at a temperature of 20 to 30°C.

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