Functional foam material as well as preparation method and application thereof
By preparing functional foam materials composed of anionic surfactants, foam stabilizers, oxidants, and additives, the problem of insufficient stability and adaptability of foam materials in complex environments was solved, achieving efficient blocking and degradation of VOCs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-12
- Publication Date
- 2026-04-17
AI Technical Summary
Existing foam materials suffer from limited stability and insufficient adaptability in engineering applications, making it difficult to effectively achieve the "blocking + degradation" effect on volatile organic compounds (VOCs) in complex environments.
Functional foam materials are prepared by combining anionic surfactants, foam stabilizers, oxidants, and additives with water. The foam forms a uniform and continuous covering layer, and the combination with advanced oxidants achieves the blocking and degradation of VOCs. The component concentration and the ratio of gaseous oxidants are optimized to improve environmental adaptability and stability.
It achieves efficient "blocking + degradation" of VOCs pollution in complex environments, with excellent coverage and barrier performance, a degradation rate of 70-80%, and maintains stable coverage for 4-8 hours at wind speeds ≤1.5m/s, demonstrating strong environmental adaptability.
Smart Images
Figure CN121869071A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of environmental pollution control technology, specifically relating to a functional foam material, its preparation method, and its application. Background Technology
[0002] Volatile organic compounds (VOCs) are ubiquitous in environments such as contaminated soil, industrial stockpiles, underground solvent spill zones, and chemical demolition sites. They are characterized by high volatility, high toxicity, high mobility, and rapid diffusion, posing a long-term threat to the ecosystem and human health.
[0003] In recent years, foam materials have been proposed as a novel shielding medium for VOCs control due to their high fluidity, ability to cover complex terrain, ease of forming continuous barriers, and certain adhesiveness, and have shown good pollutant volatilization inhibition effects. However, foam itself does not have degradation function, and pollutants are only isolated for a short time and cannot be completely removed. To this end, research has begun to explore the combination of foam with advanced oxidation technology to achieve the synergistic remediation goal of "blocking + degradation". For example, Zhang Hongling et al. combined AC-645 foam material with sodium persulfate oxidant to block and oxidize tetrachloroethylene. The blocking effect on tetrachloroethylene can be maintained at about 95.0% within 3 hours, and the removal rate of polycyclic aromatic hydrocarbons in soil is more than 80.0% after 24 hours of reaction (see Zhang Hongling, Li Sen, Zhang Yang, et al. Foam blocking synergistic oxidation remediation of tetrachloroethylene and polycyclic aromatic hydrocarbons in soil [J]. Zhejiang Journal of Agricultural Sciences, 2019, 31(07):1138-44.).
[0004] While these "blocking + degradation" technologies have shown promising results in the laboratory, they still have shortcomings in engineering applications: limited stability: high concentrations of oxidants (such as persulfate) or photocatalytic processes may accelerate the drainage and rupture of the foam liquid film, leading to a shortened barrier duration; insufficient adaptability: there is insufficient research on the synergistic removal of multi-component mixed pollution and VOCs of different volatiles, and limited adaptability to complex, heterogeneous surfaces. Therefore, how to improve foam materials to ensure strong environmental adaptability and high foam stability, so as to achieve efficient "blocking + degradation" of VOCs pollution in complex environments, has become an urgent technical problem to be solved in this field. Summary of the Invention
[0005] The purpose of this invention is to provide a functional foam material, its preparation method, and its applications. The functional foam material provided by this invention has strong environmental adaptability, high foam stability, and excellent covering and barrier properties, enabling it to achieve efficient "blocking + degradation" of VOCs pollution in complex environments.
[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a functional foam material comprising the following components: anionic surfactant, foam stabilizer, oxidant, additives, and water; When the oxidant is a solid oxidant, the functional foam material is in the liquid phase; When the oxidant is a gaseous oxidant, the functional foam material includes a liquid phase and a gas phase; The concentration of the anionic surfactant in the liquid phase is 0.2~0.4 wt%; The concentration of the foam stabilizer in the liquid phase is 0.4~0.6 wt%; The concentration of the solid oxidant in the liquid phase is 0.5~5 wt%; The concentration of the additive in the liquid phase is 1~5 wt%; The volume ratio of the gaseous oxidant to the total volume of the liquid phase is (3~4):1.
[0007] Preferably, the anionic surfactant includes at least one of sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, and sodium α-alkenyl sulfonate.
[0008] Preferably, the foam stabilizer includes at least one of xanthan gum, sodium alginate, chitosan, and gelatin.
[0009] Preferably, the auxiliary agent is citric acid and ferrous sulfate heptahydrate.
[0010] Preferably, the solid oxidant includes at least one of persulfate and percarbonate.
[0011] Preferably, the gaseous oxidant is ozone.
[0012] Preferably, the water is deionized water or on-site water.
[0013] The present invention also provides a method for preparing the functional foam material described in the above technical solution, comprising: When the oxidant is a solid oxidant, anionic surfactant, foam stabilizer, solid oxidant, additives and water are mixed and foamed to obtain functional foam material; When the oxidant is a gaseous oxidant, anionic surfactant, foam stabilizer, additives and water are mixed and foamed to obtain a functional foam material; the gaseous oxidant is injected during foaming.
[0014] Preferably, the foaming temperature is room temperature and the foaming time is 2-5 minutes.
[0015] The present invention also provides the application of the functional foam material described in the above technical solution or the functional foam material prepared by the preparation method described in the above technical solution in the treatment of volatile organic compound pollution.
[0016] This invention provides a functional foam material comprising the following components: anionic surfactant, foam stabilizer, oxidant, additives, and water; when the oxidant is a solid oxidant, the functional foam material is in a liquid phase; when the oxidant is a gaseous oxidant, the functional foam material comprises a liquid phase and a gaseous phase; the concentration of the anionic surfactant in the liquid phase is 0.2~0.4wt%; the concentration of the foam stabilizer in the liquid phase is 0.4~0.6wt%; the concentration of the solid oxidant in the liquid phase is 0.5~5wt%; the concentration of the additives in the liquid phase is 1~5wt%; and the volume ratio of the gaseous oxidant to the total volume of the liquid phase is (3~4):1. This invention uses anionic surfactant as a foaming agent, combined with a foam stabilizer and an oxidant, to rapidly form a uniform and continuous covering layer after application to the surface of a pollution source. The foam exhibits high stability, resulting in excellent covering and barrier performance and strong environmental adaptability. Experimental results show that the functional foam material provided by this invention has an average foam diameter of about 40~55μm, and its foaming capacity increases rather than decreases (foaming ratio ≥3.4). The liquid half-life is about 150~1200min. It can maintain stable coverage under wind speed ≤1.5m / s conditions, and the barrier time can reach 4~8h. The advanced oxidant loaded in the foam material can achieve in-situ degradation of VOCs while blocking, with a degradation rate of 70~80%. Attached Figure Description
[0017] Figure 1 The average cell diameter is the same as that of the functional foam materials prepared in Examples 1-3. Figure 2 The initial foaming ratios of the functional foam materials prepared in Examples 1-3; Figure 3 The half-life of the functional foam materials prepared in Examples 1-3 is the liquid separation half-life. Figure 4 The figures show the foam morphology of the functional foam materials prepared in Examples 1-3. In the figures, a is the blank group, b is the foam morphology of the functional foam material prepared in Example 1, c is the foam morphology of the functional foam material prepared in Example 2, and d is the foam morphology of the functional foam material prepared in Example 3. Figure 5 The functional foam materials prepared in Examples 1-3 and the pure foam of Comparative Example 1 are shown to inhibit the volatilization of xylene. Figure 6 The curves showing the change in the blocking rate of VOCs (xylene) volatilization of the functional foam materials prepared in Examples 1-3 and the pure foam of Comparative Example 1 are shown. Figure 7 The degradation rate of xylene in the functional foam materials prepared in Examples 1-3 is shown. Detailed Implementation
[0018] This invention provides a functional foam material comprising the following components: anionic surfactant, foam stabilizer, oxidant, additives, and water; When the oxidant is a solid oxidant, the functional foam material is in the liquid phase; When the oxidant is a gaseous oxidant, the functional foam material includes a liquid phase and a gas phase; The concentration of the anionic surfactant in the liquid phase is 0.2~0.4 wt%; The concentration of the foam stabilizer in the liquid phase is 0.4~0.6 wt%; The concentration of the solid oxidant in the liquid phase is 0.5~5 wt%; The concentration of the additive in the liquid phase is 1~5 wt%; The volume ratio of the gaseous oxidant to the total volume of the liquid phase is (3~4):1.
[0019] The present invention does not have any special limitations on the source of the raw materials, and commercially available products known to those skilled in the art can be used.
[0020] In this invention, the functional foam material comprises the following components: anionic surfactant, foam stabilizer, oxidant, additives, and water.
[0021] In this invention, the anionic surfactant preferably includes at least one selected from sodium dodecyl sulfate (SDS), sodium dodecylbenzene sulfonate (SDBS), and sodium α-alkenyl sulfonate (AOS). In this invention, the anionic surfactant acts as a foaming agent, contributing to foaming.
[0022] In this invention, the foam stabilizer preferably includes at least one of xanthan gum, sodium alginate, chitosan and gelatin, and more preferably xanthan gum.
[0023] In this invention, when the oxidant is a solid oxidant, the functional foam material is in the liquid phase; the solid oxidant preferably includes at least one of persulfate and percarbonate; the persulfate is preferably sodium persulfate; the percarbonate is preferably sodium percarbonate. In this invention, the persulfate and percarbonate are advanced oxidants, which can improve the oxidation effect.
[0024] In this invention, when the oxidant is a gaseous oxidant, the functional foam material comprises a liquid phase and a gaseous phase; the volume ratio of the gaseous oxidant to the total volume of the liquid phase is (3~4):1; the gaseous oxidant is preferably ozone. As one embodiment, the volume ratio of the gaseous oxidant to the total volume of the liquid phase can be 3:1, 3.5:1, or 4:1. In this invention, ozone is a high-grade oxidant that can improve the oxidation effect.
[0025] In this invention, the concentration of the anionic surfactant in the liquid phase is 0.2~0.4 wt%. As one embodiment, the concentration of the anionic surfactant in the liquid phase can be 0.25 wt%, 0.3 wt%, or 0.35 wt%. Limiting the concentration of the anionic surfactant within the above range further improves the foam-stabilizing effect.
[0026] In this invention, the concentration of the foam stabilizer in the liquid phase is 0.4~0.6 wt%. As one embodiment, the concentration of the foam stabilizer in the liquid phase can be 0.45 wt%, 0.5 wt%, or 0.55 wt%. Limiting the concentration of the foam stabilizer within the above range further improves the foam stabilizing effect.
[0027] In this invention, the concentration of the solid oxidant in the liquid phase is 0.5~5wt%. As one embodiment, the concentration of the solid oxidant in the liquid phase can be 0.6wt%, 0.7wt%, 0.8wt%, 0.9wt%, 1wt%, 1.5wt%, 2wt%, 2.5wt%, 3wt%, 3.5wt%, 4wt%, or 4.5wt%. Limiting the concentration of the solid oxidant within the above range further improves the oxidation effect.
[0028] In this invention, the concentration of the auxiliary agent in the liquid phase is 1-5 wt%. As one embodiment, the concentration of the auxiliary agent in the liquid phase can be 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, or 4.5 wt%. Limiting the concentration of the auxiliary agent within the above range further improves the oxidation effect.
[0029] In this invention, the auxiliary agent is preferably citric acid and ferrous sulfate heptahydrate; the mass ratio of citric acid to ferrous sulfate heptahydrate is 1:1. In this invention, citric acid and ferrous sulfate heptahydrate can activate the oxidant, thereby improving the oxidation effect.
[0030] In this invention, the water is preferably deionized water or on-site water. In this invention, the water is used as a solvent.
[0031] The foam material provided by this invention is suitable for gas concentrations ranging from 0.1 to 2000 mg / m³. 3 The volatile organic compounds have good environmental adaptability to wind speed (≤1.5m / s); the foam material provided by this invention can quickly form a uniform and continuous covering layer after being applied to the surface of the pollution source. The foam thickness can be adjusted within the range of 1~5cm according to actual needs to ensure good barrier continuity and oxidation reaction contact efficiency.
[0032] The foam material provided by this invention exhibits strong environmental adaptability, high foam stability, controllable oxidant release, and excellent coverage and barrier performance: the foam system has good fluidity and high formability, and can form a uniform and continuous covering layer on the surface of complex, irregular, or unstable pollution sources, achieving a VOCs volatilization barrier efficiency of over 90%; it has strong environmental adaptability: it can maintain stable coverage even under wind speeds ≤1.5m / s, with a barrier time of 4~8h; it has synergistic degradation function: the advanced oxidants loaded in the foam material can achieve in-situ degradation of VOCs while providing barrier protection, with a degradation rate of 70~80%, avoiding the "blocking without treating" defects of simple physical sealing; and it has high reagent utilization: the foam film confinement and high specific surface area improve the contact efficiency between VOCs and oxidants.
[0033] The physical properties of the foam material provided by this invention are as follows: initial expansion ratio: 2~4; average foam diameter: 20~100μm; foam half-life (static): ≥6h; coverage thickness: 1~5cm.
[0034] The present invention also provides a method for preparing the functional foam material described in the above technical solution, comprising: When the oxidant is a solid oxidant, anionic surfactant, foam stabilizer, solid oxidant, additives and water are mixed and foamed to obtain functional foam material; When the oxidant is a gaseous oxidant, anionic surfactant, foam stabilizer, additives and water are mixed and foamed to obtain a functional foam material; the gaseous oxidant is injected during foaming.
[0035] In this invention, when the oxidant is a solid oxidant, anionic surfactant, foam stabilizer, solid oxidant, additives and water are mixed and foamed to obtain a functional foam material.
[0036] In this invention, the mixing of the anionic surfactant, foam stabilizer, solid oxidant, additive and water is preferably carried out by mixing water and foam stabilizer, and then adding the anionic surfactant, oxidant and additive in sequence.
[0037] In this invention, the mixing of water and foam stabilizer is preferably carried out under stirring conditions; the stirring speed is preferably 300-500 rpm; and the stirring time is preferably 5-10 min. By limiting the stirring process parameters within the above range, this invention enables the foam stabilizer to be completely dispersed in the water.
[0038] As one implementation, the stirring speed can be 350 rpm, 400 rpm, or 450 rpm; the stirring time can be 6 min, 7 min, 8 min, or 9 min.
[0039] In this invention, the foam stabilizer is preferably added to water slowly. There are no particular limitations on the slow addition operation; any operation well-known to those skilled in the art can be used. Adding the foam stabilizer slowly to water avoids pouring it all at once and prevents clumping.
[0040] In this invention, the anionic surfactant is preferably stirred; the stirring speed is preferably 300-500 rpm; and the stirring time is preferably 5-10 min. As one embodiment, the stirring speed can be 350 rpm, 400 rpm, or 450 rpm; and the stirring time can be 6 min, 7 min, 8 min, or 9 min.
[0041] In this invention, the solid oxidant is preferably stirred; the stirring speed is preferably 300-500 rpm; and the stirring time is preferably 5-10 min. As one embodiment, the stirring speed can be 350 rpm, 400 rpm, or 450 rpm; and the stirring time can be 6 min, 7 min, 8 min, or 9 min.
[0042] The present invention does not impose any special limitations on the operation of adding the additives, and any technical solution for preparing the mixture well known to those skilled in the art can be used.
[0043] In this invention, the foaming temperature is preferably room temperature; the foaming time is preferably 2-5 minutes. As one embodiment, the foaming time can be 3 minutes or 4 minutes.
[0044] In this invention, the foaming is preferably carried out in a mechanical foaming machine; the rotation speed of the mechanical foaming machine is preferably 4000~5000 rpm. As one embodiment, the rotation speed of the mechanical foaming machine can be 4100 rpm, 4200 rpm, 4300 rpm, 4400 rpm, 4500 rpm, 4600 rpm, 4700 rpm, 4800 rpm, or 4900 rpm. This invention does not impose a specific limitation on the model of the mechanical foaming machine; any instrument or equipment well known to those skilled in the art can be used.
[0045] In this invention, when the oxidant is a gaseous oxidant, anionic surfactant, foam stabilizer, additives and water are mixed and foamed to obtain a functional foam material; the gaseous oxidant is injected during foaming.
[0046] In this invention, the mixing of the anionic surfactant, foam stabilizer, additives and water is preferably carried out by mixing water and foam stabilizer, and then adding the anionic surfactant and additives in sequence.
[0047] In this invention, the mixing of water and foam stabilizer is preferably the same as the operation described above with solid oxidant, and will not be repeated here.
[0048] In this invention, the operation of sequentially adding anionic surfactants is preferably the same as the operation of adding solid oxidants, and will not be described again here.
[0049] The present invention does not impose any special limitations on the operation of adding the additives, and any technical solution for preparing the mixture well known to those skilled in the art can be used.
[0050] In this invention, the foaming operation is preferably the same as the operation for the aforementioned solid oxidant, and will not be repeated here.
[0051] In this invention, the gaseous oxidant is injected during foaming; the injection rate of the gaseous oxidant is preferably 5~15 mL / min, more preferably 10 mL / min.
[0052] The preparation method provided by this invention is simple.
[0053] The present invention also provides the application of the functional foam material described in the above technical solution or the functional foam material prepared by the preparation method described in the above technical solution in the treatment of volatile organic compound pollution.
[0054] The present invention does not impose any special limitations on the application of the functional foam material; any application operation known to those skilled in the art can be used.
[0055] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.
[0056] The instruments and materials used in the examples and comparative examples are shown in Tables 1 and 2.
[0057] Table 1 Main Instruments
[0058] Table 2 Main Materials
[0059] Example 1 (Loaded SPC Foam) A functional foam material comprises the following components: SDS, xanthan gum, sodium percarbonate (SPC), citric acid, ferrous sulfate heptahydrate, and deionized water; The functional foam material is in the liquid phase; The concentration of SDS in the liquid phase is 0.2 wt%; The concentration of xanthan gum in the liquid phase is 0.5 wt%. The concentration of sodium percarbonate in the liquid phase is 2 wt%; The total concentration of citric acid and ferrous sulfate heptahydrate in the liquid phase is 4 wt%. The mass ratio of citric acid to ferrous sulfate heptahydrate is 1:1; The preparation method of the functional foam material is as follows: Add deionized water to the reaction vessel and start stirring (400 rpm) to form a stable vortex; slowly sprinkle xanthan gum while stirring and continue stirring for 5 minutes, then add SDS and stir at 400 rpm for 5 minutes, then add sodium percarbonate at 400 rpm and stir for 5 minutes, then add citric acid and ferrous sulfate heptahydrate to obtain the foaming liquid. The functional foam material was obtained by stirring with a Wu Yin mixer (4500 rpm) for 2 minutes.
[0060] Example 2 (Loaded PDS Foam) Based on Example 1, sodium percarbonate was replaced with sodium persulfate (PDS), while other conditions remained unchanged.
[0061] Example 3 (O3-loaded foam) A functional foam material comprises the following components: SDS, xanthan gum, ozone (O3), citric acid, ferrous sulfate heptahydrate, and deionized water; The functional foam material is in liquid and gas phases; The concentration of SDS in the liquid phase is 0.2 wt%; The concentration of xanthan gum in the liquid phase is 0.5 wt%. The total concentration of citric acid and ferrous sulfate heptahydrate in the liquid phase is 4 wt%. The mass ratio of citric acid to ferrous sulfate heptahydrate is 1:1; The volume ratio of ozone to the total volume of the liquid phase is 3.5:1; The preparation method of the functional foam material is as follows: Add deionized water to the reaction vessel and start stirring (400 rpm) to form a stable vortex; slowly sprinkle xanthan gum while stirring and continue stirring for 5 min; then add SDS and stir at 400 rpm for 5 min; then add citric acid and ferrous sulfate heptahydrate to obtain 100 mL of foaming solution. Stir for 2 minutes using a Wu Yin stirrer (4500 rpm), and continuously inject ozone at a flow rate of 10 mL / min during the stirring and foaming process to obtain functional foam material.
[0062] Verify the foaming ability, structural integrity, and stability of the foam systems in Examples 1-3 after adding oxidants (sodium percarbonate, ozone, sodium persulfate).
[0063] Evaluation indicators: Initial foaming ratio: The foam volume obtained after stirring 100mL of foaming liquid for 2 minutes using a Wu Yin stirrer is compared with the volume of the surfactant solution used for foaming to obtain the foaming ratio.
[0064] Half-life of the foam: Stir 100 mL of foaming solution using a Wu Yin stirrer, collect the foam, pour it into a 500 mL graduated cylinder, and record the time it takes for the solution after the foam bursts. Stop timing when 50 mL has been collected. This time is the half-life of the foam.
[0065] Average bubble diameter: The bubble particle size distribution was observed using an optical microscope. The generated water-based foam was transferred to a clear, transparent glass dish and observed under an optical microscope. The morphology of the foam was recorded using photographic software. Then, ImageJ software was used to calculate the foam particle size, and finally, IBM SPSS software was used for data statistics and analysis.
[0066] The average cell diameter of the functional foam materials prepared in Examples 1-3 is as follows: Figure 1 As shown.
[0067] The initial foaming of the functional foam materials prepared in Examples 1-3 is as follows: Figure 2 As shown.
[0068] The liquid-extraction half-life of the functional foam materials prepared in Examples 1-3 is as follows: Figure 3 As shown.
[0069] The foam morphology of the functional foam materials prepared in Examples 1-3 is as follows: Figure 4 As shown in the figure, a is the blank group, b is the foam morphology of the functional foam material prepared in Example 1, c is the foam morphology of the functional foam material prepared in Example 2, and d is the foam morphology of the functional foam material prepared in Example 3.
[0070] from Figures 1-4It can be seen that all three types of oxidants maintained a uniform fine bubble structure (average bubble diameter of approximately 40–55 μm) after loading, and the foaming capacity increased rather than decreased (expansion ratio ≥ 3.4). Furthermore, the bubble layer stability could be controlled in stages according to the type of oxidant (liquid half-life of approximately 150–1200 min). Among them, the SPC group had the highest expansion ratio and was easy to spread quickly; the PDS / SPC group combined a smaller bubble diameter with a moderate lifespan; and the ozone (O3) group had the longest maintenance time. In summary, the oxidant-loaded foam was superior to the blank foam in terms of structural integrity and maintainability, confirming the objective of "maintaining good foaming and stabilizing performance and achieving controllable maintenance after adding oxidants."
[0071] Comparative Example 1 (Pure Foam) The oxidant was omitted from Example 1, while other conditions remained unchanged.
[0072] The purpose of this invention is to evaluate whether the functional foam material can effectively suppress the gaseous release of organic matter after covering VOC pollution sources.
[0073] Experimental Design: Model and apparatus: Add 10g of xylene solution to a 500mL beaker and distribute it evenly on the surface.
[0074] Foam system and application: 20g of the functional foam materials prepared in Examples 1-3 and the pure foam of Comparative Example 1 were sprayed onto the contaminated surface, with a coverage thickness of 3cm.
[0075] Grouping and Replication: The experimental group was covered with foam, while the control group was uncovered. Each group had two replicates.
[0076] Operating conditions: fume hood, air velocity ≤1.5m / s, temperature 25±1℃.
[0077] Monitoring and sampling: Weigh the changes in the total mass of the beaker at 0, 2, 4, 6, 8, 10 and 12 h, and calculate the mass loss per unit time to assess the VOCs volatilization rate.
[0078] Data processing: The difference in mass loss between the experimental group and the control group at each time point was calculated. The blocking efficiency η was calculated using the following formula: η = (ΔM_blank - ΔM_foam) / ΔM_blank × 100%.
[0079] The inhibitory effects of the functional foam materials prepared in Examples 1-3 and the pure foam of Comparative Example 1 on xylene volatilization are as follows: Figure 5 As shown.
[0080] The curves showing the change in the blocking rate of VOCs (xylene) volatilization of the functional foam materials prepared in Examples 1-3 and the pure foam of Comparative Example 1 are as follows. Figure 6 As shown.
[0081] from Figures 5-6 It can be seen that, compared with the blank control, pure foam, ozone-loaded foam, and sodium persulfate-loaded foam achieved rapid volatilization suppression of nearly or exceeding 90% within 0-2 hours, and maintained a blocking rate of approximately 70-80% after 12 hours. Although sodium percarbonate-loaded foam could inhibit volatilization, its long-term effect decayed rapidly, with the blocking rate dropping to around 40% after 12 hours. Overall, this indicates that the foam coverage can effectively inhibit the gaseous release of organic matter, with the order being: "pure foam ≈ O3 foam > sodium persulfate foam > sodium percarbonate foam." The appropriate formulation can be selected based on the maintenance time and oxidation requirements.
[0082] Verify the in-situ chemical degradation capability of functional foam materials for VOCs: Experimental Design Model and apparatus: Add 2 mg of xylene solution to a 500 mL beaker.
[0083] Foam system and application: Spray 20g of the functional foam material prepared in Examples 1-3 onto the contaminated surface and seal it.
[0084] Grouping and Replication: The experimental group was covered with foam, while the control group was uncovered. Each group had two replicates.
[0085] Operating conditions: Temperature 25±1℃, protected from light.
[0086] Sampling: The samples were tested after 12 hours, and the residual xylene content was analyzed according to the "Determination of Benzene Series in Water by Headspace / Gas Chromatography".
[0087] Data processing: Calculate the degradation rate = (C0 - C) t ) / C0×100%, where C0 is the initial xylene concentration, C t Let t be the concentration at time t.
[0088] The degradation rate of xylene by the functional foam materials prepared in Examples 1-3 is as follows: Figure 7 As shown.
[0089] from Figure 7 It can be seen that, under the same covering and contact conditions, the foams loaded with oxidants all exhibited significant chemical degradation effects: PDS (persulfate) foam had a degradation rate of approximately 80%, SPC (percarbonate) approximately 60%, and O3 foam approximately 30%. This indicates that during the covering period, the oxidants can fully contact VOCs and undergo an oxidation reaction (PDS / SPC is activated to produce SO42-). - •OH, free radical oxidation; O3 mainly performs direct oxidation), thereby achieving in-situ degradation of organic matter; the degradation intensity corresponding to different oxidants can be graded and controlled, with O3 showing the overall trend of degradation. <SPC<PDS。
[0090] As can be seen from the above embodiments and comparative examples, the functional foam material provided by the present invention has strong environmental adaptability, high foam stability, and excellent covering and barrier properties, and can achieve efficient “blocking + degradation” of VOCs pollution in complex environments.
[0091] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A functional foam material, comprising the following components: anionic surfactant, foam stabilizer, oxidant, additives, and water; When the oxidant is a solid oxidant, the functional foam material is in the liquid phase; When the oxidant is a gaseous oxidant, the functional foam material includes a liquid phase and a gas phase; The concentration of the anionic surfactant in the liquid phase is 0.2~0.4 wt%; The concentration of the foam stabilizer in the liquid phase is 0.4~0.6 wt%; The concentration of the solid oxidant in the liquid phase is 0.5~5 wt%; The concentration of the additive in the liquid phase is 1~5 wt%; The volume ratio of the gaseous oxidant to the total volume of the liquid phase is (3~4):
1.
2. The functional foam material according to claim 1, characterized in that, The anionic surfactant includes at least one of sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, and sodium α-alkenyl sulfonate.
3. The functional foam material according to claim 1, characterized in that, The foam stabilizer includes at least one of xanthan gum, sodium alginate, chitosan, and gelatin.
4. The functional foam material according to claim 1, characterized in that, The additives are citric acid and ferrous sulfate heptahydrate.
5. The functional foam material according to claim 1, characterized in that, The solid oxidant includes at least one of persulfate and percarbonate.
6. The functional foam material according to claim 1, characterized in that, The gaseous oxidant is ozone.
7. The functional foam material according to claim 1, characterized in that, The water is deionized water or on-site water.
8. A method for preparing the functional foam material according to any one of claims 1 to 7, comprising: When the oxidant is a solid oxidant, anionic surfactant, foam stabilizer, solid oxidant, additives and water are mixed and foamed to obtain functional foam material; When the oxidant is a gaseous oxidant, anionic surfactant, foam stabilizer, additives and water are mixed and foamed to obtain a functional foam material; the gaseous oxidant is injected during foaming.
9. The preparation method according to claim 8, characterized in that, The foaming temperature is room temperature, and the foaming time is 2-5 minutes.
10. The application of the functional foam material according to any one of claims 1 to 7 or the functional foam material prepared by the preparation method according to claim 8 or 9 in the treatment of volatile organic compound pollution.