Air peculiar smell removing agent for spraying and preparation method of air peculiar smell removing agent

Abstract

The invention relates to the technical field of air purification, in particular to an air peculiar smell removing agent for spraying and a preparation method thereof, and the air peculiar smell removing agent comprises nano-zinc oxide, organic acid copper or copper carbonate. According to the removing agent disclosed by the invention, the nanometer oxidizing agent is used as a main functional component, and the organic acid copper or copper carbonate is added, so that the stability is better, and the removing agent still has a remarkable peculiar smell removing effect within a relatively long period and does not generate white spots.

Description

Technical Field

[0001] This invention relates to the field of air purification technology, specifically to an air odor remover for spraying and its preparation method. Background Technology

[0002] As people's demands for quality of life and environmental conditions increase, air odor control has become an important issue. Traditional odor removal products mostly rely on fragrances to mask odors or activated carbon to absorb them. However, masking odors with fragrances is unlikely to remove them from their essence, and the mixed smells can sometimes be even more unpleasant. Activated carbon is usually in the form of static carbon packets, which is ineffective at removing odors that are already floating in the air.

[0003] Nano zinc oxide, due to its strong oxidizing properties and broad-spectrum antibacterial capabilities, has been widely studied for its application in air purification. For example, CN110117446A discloses a multi-effect spray specifically for automotive air conditioning filters, composed of the following components by mass percentage: 3-10% nano zinc oxide, 0.3-5.0% dispersant, 1-10% formaldehyde removal agent, 0.5-5.0% deodorizer, 0.1-5.0% film-forming agent, and the balance deionized water. While this spray exhibits certain effects in formaldehyde removal, deodorization, antibacterial activity, and mildew prevention, it suffers from poor stability and a short effective period; its effectiveness significantly decreases after a certain period of time. Summary of the Invention

[0004] This invention provides an air odor remover for spraying and its preparation method. The remover uses nano-oxidants as the main functional component, has better stability, and still has a significant odor removal effect over a longer period of time.

[0005] In a first aspect, the present invention provides an air odor remover for spraying, the raw materials of which include: nano zinc oxide, organic copper acid, or copper carbonate.

[0006] The inventors conducted experimental analysis on existing sprays containing nano-zinc oxide. While zinc oxide has excellent odor removal effects, the effect is significantly reduced when used in spray form compared to using zinc oxide powder directly. Furthermore, they found that the spray form works best when freshly prepared, but the odor removal effect diminishes considerably after a period of time. It is speculated that this is because nano-zinc oxide readily aggregates and precipitates in water, resulting in poor dispersion stability and limiting its application in liquid spray products.

[0007] Subsequent research and development revealed that adding organic copper acids or copper carbonate to the nano zinc oxide spray formulation effectively improves odor removal and extends its shelf life. Furthermore, it was found that current nano zinc oxide sprays often leave white residue ("white spots") after drying on surfaces, affecting aesthetics and hindering their adoption in daily consumer products. Adding organic copper acids or copper carbonate prevents this residue. Further investigation showed that adding organic copper acids or copper carbonate significantly reduces the concentration of zinc oxide used; a significant odor-neutralizing effect is achieved at concentrations below 500 ppm.

[0008] Preferably, the organic copper acid is at least one of copper citrate and copper acetate.

[0009] Preferably, in the air odor remover, the weight ratio of nano zinc oxide to organic acid copper or copper carbonate is 80-100:9-10. This ratio range ensures that the copper component is sufficient to cover the ZnO surface and form an effective modification layer.

[0010] More preferably, the weight ratio of the nano zinc oxide to organic acid copper or copper carbonate is 10:1.

[0011] Preferably, the concentration of nano zinc oxide in the air odor remover is 100–500 ppm.

[0012] Preferably, the concentration of organic copper acid or copper carbonate in the air odor remover is 10–60 ppm.

[0013] Preferably, the air odor remover also includes a dispersant.

[0014] Preferably, the air odor remover also includes 0.1–5 ppm of iron or manganese salt as a co-catalyst.

[0015] The present invention also provides a method for preparing the aforementioned air odor remover for spraying, comprising the following steps:

[0016] (a) Mix nano zinc oxide, organic copper acid or copper carbonate with deionized water, heat to near boiling and stir;

[0017] (b) Introduce carbon dioxide gas into the reaction system to allow the reaction to proceed to completion;

[0018] (c) After cooling to room temperature, filter to obtain filter cake;

[0019] (d) The filter cake is dried at low temperature, pulverized, and heat-treated at 200-220°C to constant weight, then pulverized again to obtain copper-coated zinc oxide powder;

[0020] (e) The obtained copper-coated zinc oxide powder is mixed with water and optional dispersant, and then ground and dispersed to obtain a stable dispersion with a particle size D50 of 40–70 nm and D90 of 60–90 nm.

[0021] (f) The dispersion is diluted with water to obtain the air odor remover.

[0022] Preferably, the grinding and dispersion time in step (e) is 6–10 hours.

[0023] Preferably, the dilution factor in step (f) is 500–2000 times.

[0024] The present invention also provides the application of the aforementioned air odor remover in indoor and outdoor spaces, fabric surfaces, or air conditioning systems.

[0025] By implementing the above technical solution, compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. This invention achieves rapid and thorough deodorization even at low concentrations (≤500 ppm nano zinc oxide) through the synergistic effect of nano zinc oxide and organic acid copper (or copper carbonate).

[0027] 2. This invention employs an in-situ reaction combined with heat treatment to form a copper-coated / surface-modified zinc oxide structure, which effectively inhibits the aggregation of nanoparticles. After 3 months of storage, the odor removal rate of the deodorizing spray is far superior to that of the control product without copper components.

[0028] 3. This invention regulates the crystallization behavior of zinc oxide during the drying process, preventing it from accumulating on the surface of objects to form white deposits, and leaving no visible residue on various substrates such as black leather, glass, ceramic tiles, and fabrics. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of protection of this invention.

[0030] Example 1

[0031] 100 kg of commercially available nano zinc oxide powder (average particle size approximately 50 nm) and 900 kg of deionized water were added to a reaction vessel and heated to 95°C with stirring. Then, 10 kg of copper citrate was added, and stirring continued for 30 minutes. Carbon dioxide gas was introduced (flow rate 1.5 L / min) and the reaction was continued for 2 hours. After the reaction was completed, the mixture was cooled to room temperature and filtered to obtain a filter cake. The filter cake was vacuum dried at 60°C for 12 hours, pulverized, and then calcined in a muffle furnace at 220°C for 4 hours. After natural cooling, it was ball-milled again to obtain copper-coated zinc oxide composite powder.

[0032] Take 60 kg of the above composite powder, add 110 kg of deionized water and 1.2 kg of sodium polyacrylate dispersant (accounting for 2% of the total solid content), emulsify by high-speed shearing for 30 minutes, and then transfer to a sand mill for grinding for 8 hours to obtain a stable dispersion. The particle size distribution was measured by a laser particle size analyzer, with D50 = 55 nm and D90 = 78 nm.

[0033] For use, dilute the dispersion with deionized water at a ratio of 1:1000 (by mass) to obtain the final spray-type air odor remover. GC-MS analysis showed that in a sealed chamber, the removal rate of ammonia (initial concentration 5 ppm) reached 83% within 30 minutes, and the removal rate of ethanethiol (initial concentration 1 ppm) reached 79%. After 3 months of storage, the removal rate of ammonia was 80%, and the removal rate of ethanethiol was 76%.

[0034] Example 2

[0035] 80 kg of commercially available nano zinc oxide powder (average particle size approximately 50 nm) and 900 kg of deionized water were added to a reaction vessel and heated to 95°C with stirring. Then, 10 kg of copper acetate was added, and stirring continued for 30 minutes. Carbon dioxide gas was introduced (flow rate 1.5 L / min) and the reaction was continued for 2 hours. After the reaction was completed, the mixture was cooled to room temperature and filtered to obtain a filter cake. The filter cake was vacuum dried at 60°C for 12 hours, pulverized, and then calcined in a muffle furnace at 220°C for 4 hours. After natural cooling, it was ball-milled again to obtain copper-coated zinc oxide composite powder.

[0036] Take 60 kg of the above composite powder, add 110 kg of deionized water and 1.2 kg of sodium polyacrylate dispersant (accounting for 2% of the total solid content), emulsify by high-speed shearing for 30 minutes, and then transfer to a sand mill for grinding for 8 hours to obtain a stable dispersion. The particle size distribution was measured by a laser particle size analyzer, with D50 = 55 nm and D90 = 78 nm.

[0037] For use, dilute the dispersion with deionized water at a ratio of 1:1500 (by mass) to obtain the final spray-type air odor remover. GC-MS analysis showed that in a sealed chamber, the removal rate of ammonia (initial concentration 5 ppm) reached 80% within 30 minutes, and the removal rate of ethanethiol (initial concentration 1 ppm) reached 74%. After 3 months of storage, the removal rate of ammonia was 76%, and the removal rate of ethanethiol was 72%.

[0038] Example 3

[0039] 100 kg of commercially available nano zinc oxide powder (average particle size approximately 50 nm) and 900 kg of deionized water were added to a reaction vessel and heated to 95°C with stirring. Then, 10 kg of copper carbonate was added, and stirring continued for 30 minutes. Carbon dioxide gas was introduced (flow rate 1.5 L / min) and the reaction was continued for 2 hours. After the reaction was completed, the mixture was cooled to room temperature and filtered to obtain a filter cake. The filter cake was vacuum dried at 60°C for 12 hours, pulverized, and then calcined in a muffle furnace at 220°C for 4 hours. After natural cooling, it was ball-milled again to obtain copper-coated zinc oxide composite powder.

[0040] Take 60 kg of the above composite powder, add 110 kg of deionized water and 1.2 kg of sodium polyacrylate dispersant (accounting for 2% of the total solid content), emulsify by high-speed shearing for 30 minutes, and then transfer to a sand mill for grinding for 8 hours to obtain a stable dispersion. The particle size distribution was measured by a laser particle size analyzer, with D50 = 55 nm and D90 = 78 nm.

[0041] For use, dilute the dispersion with deionized water at a ratio of 1:1000 (by mass) to obtain the final spray-type air odor remover. GC-MS analysis showed that in a sealed chamber, the removal rate of ammonia (initial concentration 5 ppm) reached 90% within 30 minutes, and the removal rate of ethanethiol (initial concentration 1 ppm) reached 80%. After 3 months of storage, the removal rate of ammonia was 88%, and the removal rate of ethanethiol was 79%.

[0042] Example 4

[0043] Based on Example 1, an additional 0.3 kg of ferrous sulfate heptahydrate (equivalent to approximately 2 ppm Fe²⁺ concentration) was added to the dispersion. The remaining steps were the same. Under the same test conditions, the resulting spray improved the removal rate of ammonia (initial concentration 5 ppm) from 83% to 94% within 30 minutes. After 3 months of storage, the ammonia removal rate was 81%.

[0044] Comparative Example 1

[0045] Spray containing only nano zinc oxide

[0046] Take 100 kg of commercially available nano zinc oxide powder, add 110 kg of deionized water and 1.2 kg of sodium polyacrylate dispersant, emulsify at high speed for 30 minutes, then transfer to a sand mill and grind for 8 hours to obtain a stable dispersion. When using, dilute the dispersion with deionized water at a ratio of 1:1000 (by mass) to obtain the final spray-type air odor remover.

[0047] Under the same conditions, the removal rate of ammonia (initial concentration 5 ppm) was 62% after 30 minutes, and the removal rate of ethanethiol (initial concentration 1 ppm) reached 64%. After 3 months, the removal rate of ammonia decreased to 31%, and the removal rate of ethanethiol decreased to 24%.

[0048] Comparative Example 2

[0049] 100 kg of nano-zinc oxide and 10 kg of copper citrate were directly dry-mixed and then dispersed in 110 kg of deionized water and 1.2 kg of sodium polyacrylate dispersant. After high-speed shear emulsification for 30 minutes, the mixture was ground in a sand mill for 8 hours to obtain a stable dispersion. For use, this dispersion was diluted with deionized water at a ratio of 1:1000 (by mass) to obtain the final spray-type air odor remover. Under the same conditions, the removal rate of ammonia (initial concentration 5 ppm) was 65% after 30 minutes, and the removal rate of ethanethiol (initial concentration 1 ppm) reached 62%. After 3 months of storage, the removal rate of ammonia decreased to 35%, and the removal rate of ethanethiol decreased to 21%.

[0050] The air odor removers obtained in the above embodiments and comparative examples were sprayed onto clean, high-gloss black leather, with consistent spray distance and spray volume; they were then allowed to air dry at room temperature for 2 hours. Visual inspection was then conducted by at least three trained observers under a standard light source box (D65 daylight source, illuminance ≥1000 lux).

[0051] Judgment criteria:

[0052] No white spots: The surface is free of any visible white spots, hazy deposits, or abnormal luster;

[0053] Mild vitiligo: A faint white haze can be seen at certain angles, but it is not obvious when viewed directly from the front;

[0054] Obvious white patches: White granules, streaks, or whitish areas are clearly visible to the naked eye.

[0055] Results: The air odor removers corresponding to Examples 1-4 did not have white spots, while Comparative Examples 1 and 2 had obvious white spots.

[0056] Application Example 1

[0057] A user owned two large dogs, and the living room carpet and sofa had long-standing residues of urine and body odor. Commercially available fragrance sprays could only temporarily mask the smell. Instead, they used the deodorizing spray from Example 1 of this invention, lightly spraying it daily on the pets' activity areas and fabric surfaces. After three consecutive days of use, the ammonia and fishy odors were significantly reduced; after seven days, visitors could not detect any pet odor. The fabrics showed no white spots and did not change color.

[0058] Application Example 2

[0059] A fresh food logistics company found that the refrigerated trucks used for transporting seafood had a strong fishy smell on the inner walls and sealing strips of the compartment. The deodorizing agent spray of Example 1 of this invention was used to spray the entire inner surface of the compartment. After standing for 30 minutes and then being ventilated, there was no obvious odor and no obvious white spots were observed.

[0060] Application Example 3

[0061] A subway station's underground restroom had a persistent foul odor from a mixture of hydrogen sulfide and ammonia. Cleaning staff regularly sprayed the deodorizing agent described in Example 1 of this invention. After one week of operation, on-site sensor data showed that the H2S concentration remained stable below 0.01 ppm (the national standard limit is 0.01 ppm), the ammonia concentration decreased, and there was no noticeable odor.

Claims

1. An air odor remover for spraying, characterized in that, Raw materials include: Nano zinc oxide, organic acid copper, or copper carbonate.

2. The air odor remover for spraying according to claim 1, characterized in that, The organic copper acid is at least one of copper citrate and copper acetate.

3. The air odor remover for spraying according to claim 1, characterized in that, The weight ratio of the nano zinc oxide to organic acid copper or copper carbonate is 80-100:9-10.

4. The air odor remover for spraying according to claim 1, characterized in that, The weight ratio of the nano zinc oxide to organic acid copper or copper carbonate is 10:

1.

5. An air odor remover for spraying according to claim 1, characterized in that, The concentration of the nano zinc oxide is 100-500 ppm.

6. The air odor remover for spraying according to claim 1, characterized in that, The concentration of the organic acid copper or copper carbonate is 10-60 ppm.

7. An air odor remover for spraying according to claim 1, characterized in that, It also includes 0.1-5 ppm of iron or manganese salts as co-catalysts.

8. A method for preparing an air odor remover for spraying as described in any one of claims 1-7, characterized in that, Includes the following steps: (a) Mix nano zinc oxide, organic copper acid, or copper carbonate with deionized water, heat, and stir; (b) Introduce carbon dioxide gas into the reaction system to allow the reaction to proceed to completion; (c) After cooling to room temperature, filter to obtain filter cake; (d) The filter cake is dried at low temperature, pulverized, and heat-treated at 200-220°C to constant weight, then pulverized again to obtain the removal agent powder; (e) The obtained powder is mixed with water and a dispersant, and then ground and dispersed to obtain a dispersion; (f) The dispersion is diluted with water to obtain the air odor remover.

9. The preparation method according to claim 8, characterized in that, The grinding and dispersion time in step (e) is 6-10 hours.

10. The preparation method according to claim 8, characterized in that, The dilution factor mentioned in step (f) is 500-2000 times.