Renewable gas absorption materials and devices

Abstract

The present invention relates to an aqueous regenerative filter for absorbing harmful gases and a method for preparing the same. The regenerative filter absorbs gas components in the air and has excellent reversible absorption performance for gases such as carbon dioxide, ammonia, methane, halogens, hydrogen sulfide, and sulfur dioxide. Filters based on nanocomposite or hybrid hydrogels are highly hydrated polymer networks that are physically or covalently crosslinked to each other and / or have nanoparticles or nanostructures with very large surface areas.

Description

[Technical Field]

[0001] The present invention relates to a gas absorbing material, more particularly to a renewable aqueous filter for absorbing harmful gases and a method for preparing the same. [Background technology]

[0002] Human activities have increased the concentration of carbon dioxide and other greenhouse gases in the environment, which has become a major problem in recent years. In commercial buildings, air quality is often maintained by replacing indoor air to reduce carbon dioxide concentrations to safe levels. Absorption (gas absorption) is a unit operation used in the chemical industry to separate gases by washing or scrubbing a gas mixture with a suitable liquid. The basic physical principles underlying the gas absorption process are the solubility of the absorbed gas and the rate of mass transfer.

[0003] Gas scrubbers can be applied as a technology to control emissions of various gaseous emissions. A gas scrubber is a cleaning device that brings a gas stream into intensive contact with a fluid in order to remove gaseous components from the gas into the fluid.

[0004] The following literature was referenced:

[0005] Japanese Patent Laid-Open Publication No. 11-90219 provides an adsorbent having a high carbon dioxide adsorption / desorption capacity, a small pressure loss, a high thermal diffusion efficiency, and a high resistance to repeated stresses such as expansion and contraction, and an adsorption / desorption device including the adsorbent. The adsorbent is made of a compound having a carbon dioxide adsorption / desorption capacity, and has a three-dimensional mesh framework structure or a structure having three-dimensional mesh voids.

[0006] US8808546B2 relates to a system and process for removing hydrocarbons from a gas process feed stream. Treatment processes include, but are not limited to, glycol dehydration, amine sweetening, and MEG regeneration. In one example, a hydrocarbon removal bed containing a solid adsorbent material adsorbs hydrocarbons in an MEG-rich feed stream as it passes through the hydrocarbon removal bed. After the hydrocarbons are removed, the feed stream flows through a flash separator and a distillation column to regenerate the MEG.

[0007] WO2016024633A1 A gel particle membrane of polymer compound particles having amino groups has a high acid gas absorption / desorption amount per unit volume, a high acid gas absorption / desorption rate per unit mass, and high stability. A gas absorber in which this gel particle membrane is supported on a carrier is useful as an acid gas separation material with high energy efficiency.

[0008] Japanese Patent Application Laid-Open No. 2010-167324 relates to a gas absorption filter and a gas absorption device that improves single-pass absorption performance, enables an increase in the amount of adsorbent packed therein, and aims to extend the lifespan.

[0009] CN1511081A relates to a gas absorbent material composed of high-temperature charcoal carbonized at a temperature of about 800°C or higher, low-temperature charcoal carbonized at a temperature of about 500°C or lower, and alginic acid or its salt or calcium oxide. The combined use of high-temperature charcoal, low-temperature charcoal, alginic acid component, or calcium oxide significantly improves the gas absorption performance of the charcoal. The gas adsorbent material of the present invention can be used as a gas adsorbent with excellent gas adsorption properties, and can be used particularly as an interior building material for adsorbing toxic gases present indoors.

[0010] US8211202B2 relates to a gas absorbing substance that contains at least Li and a solid material with a hardness of 5 or more and absorbs at least nitrogen or oxygen at normal pressure and 25°C. It also relates to a gas storage alloy that contains a gas storage substance that absorbs at least nitrogen or oxygen at normal pressure and at least two metals that do not form intermetallic compounds with each other, the mixing enthalpy of the two metals being greater than 0, and at least a portion of the two metals being atomically mixed, and it also relates to a gas storage material that contains the gas storage substance and the gas storage alloy.

[0011] Hikmet Sayilkan and Ertugrul Arpac published a research paper titled "Development and Application of a Renewable Filter System for the Adsorption of Air Pollutants." A new filter for preventing air pollution has been developed. Spherical amorphous silicates (such as KC-Siliperl AF 125 and aluminum silicate 596 FA) were coated with different materials prepared from hydrolytic condensation products of organically modified silanes and metal alkoxides. The adsorption capacity of these silicates for different solvents, such as ethyl acetate, toluene, n-hexane, and cyclohexanone, was investigated.

[0012] While these wet scrubbers are clearly beneficial in preventing various pollutants from entering the atmosphere through exhaust gases, they also have several drawbacks. These machines require frequent maintenance and can be subject to significant corrosion. Furthermore, these scrubbers have a large footprint, require large amounts of water, and produce large amounts of waste liquid. Therefore, an alternative to these scrubbers is needed. The present invention relates to a water-based regenerable filter for absorbing harmful gases and a method for preparing the same. The regenerable filter absorbs gas components from the air and has excellent reversible absorption performance for gases such as carbon dioxide, ammonia, methane, halogens, hydrogen sulfide, and sulfur dioxide. Nanocomposite or hybrid hydrogel-based filters are highly hydrated polymer networks that are physically or covalently crosslinked with each other or with nanoparticles or nanostructures, resulting in very large surface areas. A wide range of nanoparticles, including carbon-based, polymeric, ceramic, and metallic nanomaterials, can be incorporated into the hydrogel structure to obtain nanocomposites with tailored functionality. Nanocomposite hydrogels can be engineered to have excellent physical, chemical, electrical, thermal, and biological properties.

[0013] The information disclosed in the Background section of this disclosure is intended to enhance understanding of the general background of the present invention and should not be construed as an admission or in any way suggesting that this information forms prior art already known to those skilled in the art.

[0014] The main object of the present invention is to provide an aqueous regenerable filter for absorbing harmful gases and a method for preparing the same.

[0015] Another object of the present invention is to provide a regenerable hydrogel filter that has excellent reversible absorption efficiency for gases such as carbon dioxide, ammonia, methane, halogens, hydrogen sulfide, and sulfur dioxide. Summary of the Invention

[0016] The present invention seeks to overcome the problems faced by the prior art by disclosing a water-based, regenerable filter for absorbing gas components from air. The regenerable gel-based filter has excellent reversible absorption performance for gases such as carbon dioxide, ammonia, methane, halogens, hydrogen sulfide, and sulfur dioxide.

[0017] In one embodiment of the present invention, nanocomposite or hybrid hydrogel-based filters are highly hydrated polymer networks that are crosslinked with each other and / or with nanoparticles or nanostructures.

[0018] In one embodiment, the present invention relates to a regenerable hydrogel filter media sorbent comprising at least 10-50% wt / vol base material; at least 0.1-1% wt / vol water-retaining polymeric material (wherein a crosslinking agent is added to induce crosslinking of the polymeric material); at least 0.1-5% wt / vol active material that aids in gas adsorption; and at least 50-95% wt / vol water.

[0019] In yet another embodiment of the present invention, the substrate of the hydrogel filter media sorbent is at least one of carbon nanomaterials (carbon nanotubes or CNTs, graphene, nanodiamond), polymeric nanoparticles (dendrimers and hyperbranched polymers), inorganic / ceramic nanoparticles (hydroxyapatite, silicates, alumina, and calcium phosphate), and metal / metal oxide nanoparticles (gold, silver, and iron oxide); inorganic nanoparticles consisting of nanohydroxyapatite (nHA), synthetic silicate nanoparticles (nanoclay), bioactive glass, silica, calcium phosphate, glass ceramic, wollastonite such as CaSiO3, and combinations thereof.

[0020] In yet another embodiment of the present invention, the polymeric material that retains water within the filter is at least one of synthetic polymers such as polyacrylamide, polyethylene glycol, polyethylhydroxyethylmethacrylate, polyvinylpyrrolidone, poly N-isopropylacrylamide, polyacrylamide, and natural polymers such as gelatin, alginate, chitosan, collagen, silk, cellulose, fibrin, hyaluronic acid, agarose, and combinations thereof.

[0021] In one embodiment of the present invention, the cross-linking agent is at least one of a base such as NaOH ammonium hydroxide, an amine; and / or radiation such as ultrasound, UV or gamma irradiation, and combinations thereof, and the active material that retains the corrosive gas is at least one of KOH, calcium and magnesium oxides, and combinations thereof.

[0022] In an exemplary embodiment of the present invention, the present invention provides a method for preparing a hydrogel filter, comprising: (a) preparing a hydrogel component by dissolving at least 0.1-1% wt / vol of a polymer in water; (b) adding at least a crosslinking agent to induce and / or initiate crosslinking and thickening of the hydrogel in the form of a layer; (c) adding at least 0.1-5% wt / vol of an active substance to at least 10-50% wt / vol of a substrate by a mixing process to prepare an active substrate; and (d) sandwiching and / or mixing the thickened hydrogel from step (b) with the active substrate, wherein the active substance is mixed with the substrate with or without a binder so as not to disturb the gel composition upon contact. The hydrogel and active substrate may be mixed in different ratios, such as 1:1 or 10:1, and may also be sandwiched into a panel-type filter in which the hydrogel is sandwiched between the active substrate in layers.

[0023] In one embodiment of the present invention, hydrogels are fabricated as chemically thermoset gels by converting a polymer-water mixture into a cross-linked gel by introducing a cross-linking agent. In another embodiment of the present invention, cross-linking of existing polymers is achieved through different routes such as heating, ultrasound, UV or gamma irradiation, and combinations thereof, allowing for patterning of filters using a mask.

[0024] In yet another embodiment of the present invention, due to the regenerable nature of the filter, fresh water is added to the hydrogel filter media sorbent after treatment with corrosive gases to replenish the filter and make it truly regenerable. In one embodiment, the corrosive gas-laden water is condensed on a plate / radiator assembly in the path of the gas-laden air, and fresh water is added to the gel network to replenish the filter.

[0025] In yet another embodiment, the present invention discloses a gas absorber system that uses a gas absorption material, a gas separation material, a filter, and a gas separation device.

[0026] In another embodiment of the present invention, when dissolving acidic gases, the endogel is often slightly alkaline, which improves the neutralization capacity of the filter. Similarly, the acidity and alkalinity of the filter can be adjusted based on the target gas, and specific chemical compositions for selectively capturing gases are also disclosed by the present invention.

[0027] In another preferred embodiment, the present invention discloses a regenerative filter device consisting of a fan or vacuum system that generates negative pressure, sucking contaminated gases into the filter and dissolving and adsorbing them into the media very efficiently. Once the filter is fully saturated, a heating coil is switched on manually or automatically to evaporate the water containing the gas molecules. This water can be sent to the exhaust or collected using a condenser coil and properly discharged. Compared to wet scrubbers, the amount of water used is significantly less. Additionally, the condenser can be left on if you want to avoid increasing humidity in the discharge pump.

[0028] In yet another embodiment of the present invention, the present invention can be used in the future in the commercial sector such as airports, hospitals, data centers, schools, residential buildings etc. as well as in the industrial sector such as oil and gas industry, cement and chemical manufacturing etc.

[0029] In yet another embodiment, the present invention provides a gas absorber that is inexpensive and easy to manufacture, allowing for significant reductions in labor costs. Regeneration is based on the unique responsiveness to radiation, temperature, and electric or magnetic fields due to its special composition. Changes in the environment can induce swelling, moisture release and absorption, and the release of contents trapped within the network. This property makes the material of the present invention excellent for regeneration.

[0030] The foregoing summary is illustrative and is not intended to be in any way limiting. In addition to the exemplary aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description. DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] While embodiments of the present disclosure are amenable to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and described below. It is to be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is intended to cover all modifications, equivalents, and alternatives falling within the scope of the present disclosure. Moreover, the phraseology and terminology employed herein is for the purpose of description only and not of limitation.

[0032] As used in this disclosure, the terms "comprises," "comprising," or other variations thereof are intended to cover a non-exclusive inclusion, such that a device, apparatus, system, assembly, or method consisting of a list of components or sequence of steps does not include only those components or steps, but may include other components or steps not expressly listed or inherent in such apparatus, assembly, or device. In other words, one or more elements or steps in a system or apparatus or process preceded by "comprises...a" or "comprising...of" does not, without more constraints, exclude the presence of other or additional elements or steps in the system or apparatus or process, as the case may be.

[0033] The main object of the present invention is to provide an aqueous regenerable filter for absorbing harmful gases and a method for preparing the same.

[0034] According to an embodiment of the present invention, the present invention relates to a water-based regenerable filter medium for absorbing gas components in air. This gel-based filter medium has excellent reversible absorption performance for gases such as carbon dioxide, ammonia, methane, halogens, hydrogen sulfide, and sulfur dioxide from air. The present invention discloses a hydrogel-based regenerable filter material / media composed of synthetic and natural polymers, high-surface-area absorbents such as calcium chloride, gel beads, zeolites, molecular sieves, and calcium and magnesium oxides, and nanomaterials to provide scaffolding and structural support. The filter is based on nanocomposite hydrogels, also known as hybrid hydrogels. These are highly hydrated polymer networks, typically 90% or more by volume, physically or covalently crosslinked to each other and / or to nanoparticles or nanostructures. A wide range of nanoparticles, including carbon-based, polymer-based, ceramic-based, and metal-based nanomaterials, can be incorporated into the hydrogel structure to yield nanocomposites with tailored functionality. Nanocomposite hydrogels can be engineered to possess excellent physical, chemical, electrical, thermal, and biological properties.

[0035] According to an embodiment, the present invention relates to a regenerable hydrogel filter media sorbent comprising at least 10-50% wt / vol base material; at least 0.1-1% wt / vol water-retaining polymeric material (wherein a cross-linking agent is added to induce cross-linking of the polymeric material); at least 0.1-5% wt / vol active material that aids in gas adsorption; and at least 50-95% wt / vol water.

[0036] In one embodiment of the present invention, the substrate of the hydrogel filter media sorbent is at least one of carbon nanomaterials (carbon nanotubes or CNTs, graphene, nanodiamond), polymeric nanoparticles (dendrimers and hyperbranched polymers), inorganic / ceramic nanoparticles (hydroxyapatite, silicates, alumina, and calcium phosphate), and metal / metal oxide nanoparticles (gold, silver, and iron oxide); inorganic nanoparticles consisting of nanohydroxyapatite (nHA), synthetic silicate nanoparticles (nanoclay), bioactive glass, silica, calcium phosphate, glass ceramic, wollastonite such as CaSiO3, and combinations thereof.

[0037] In another embodiment of the present invention, the polymeric material that retains water within the filter is at least one of synthetic polymers such as polyacrylamide, polyethylene glycol, polyethylhydroxyethylmethacrylate, polyvinylpyrrolidone, poly N-isopropylacrylamide, polyacrylamide, and natural polymers such as gelatin, alginate, chitosan, collagen, silk, cellulose, fibrin, hyaluronic acid, agarose, and combinations thereof.

[0038] In yet another embodiment of the present invention, the cross-linking agent is at least one of a base such as NaOH, ammonium hydroxide, an amine; and / or radiation such as ultrasound, UV or gamma irradiation, and combinations thereof, and the active material for retaining corrosive gases is at least one of KOH, oxides of calcium and magnesium, and combinations thereof.

[0039] In an exemplary embodiment of the present invention, the present invention provides a method for preparing a hydrogel filter, comprising: (a) preparing a hydrogel component by dissolving at least 0.1-1% wt / vol of a polymer in water; (b) adding at least a crosslinking agent to induce and / or initiate crosslinking and thickening of the hydrogel in the form of a layer; (c) adding at least 0.1-5% wt / vol of an active substance to at least 10-50% wt / vol of a substrate by a mixing process to prepare an active substrate; and (d) sandwiching and / or mixing the thickened hydrogel from step (b) with the active substrate, wherein the active substance is mixed with the substrate with or without a binder so as not to disturb the gel composition upon contact. The hydrogel and active substrate may be mixed in different ratios, such as 1:1 or 10:1, and may also be sandwiched into a panel-type filter in which the hydrogel is sandwiched between the active substrate in layers.

[0040] In one embodiment of the present invention, hydrogels are fabricated as chemically thermoset gels by converting a polymer-water mixture into a cross-linked gel by introducing a cross-linking agent. In another embodiment of the present invention, cross-linking of existing polymers is achieved through different routes such as heating, ultrasound, UV or gamma irradiation, and combinations thereof, allowing for patterning of filters using a mask.

[0041] In another embodiment of the invention, due to the regenerable nature of the filter, fresh water is added to the hydrogel filter media sorbent after treatment with corrosive gases, making the filter truly regenerable. In one embodiment, the corrosive gas-laden water is condensed on a plate / radiator assembly in the path of the gas-laden air, and fresh water is added to the gel network to replenish the filter.

[0042] In yet another embodiment of the present invention, selectivity is imparted by using a polymer network of gel-based filters to selectively adsorb corrosive gases from air and gas streams.

[0043] According to an embodiment of the present invention, a regenerable filter media is composed of up to 1% (wt / V) acrylamide or polyacrylic acid polymer, approximately 50% (wt / V) carbon backbone material such as activated carbon, and a final volume of water. Because of the very large surface area, gases dissolve very efficiently in water, and dissolution depends on the gas's dissolving capacity. For example, at 293 K, the following gases have good solubility: The weight of gas dissolved in 100 g of water at a total pressure of 1 atmosphere above the solution is in grams (Table 1).

[0044] [Table 1]

[0045] On the other hand, the following gases have poor solubility, so the filter of the present invention can selectively remove "soluble" gases (Table 2). For example, carbon dioxide can be selectively removed from air (mainly nitrogen and oxygen).

[0046] [Table 2]

[0047] In another embodiment, the present invention discloses a gas absorber system using a gas absorption material, a gas separation material, a filter, and a gas separation device. The system comprises a water-gas absorption material made of polyacrylamide gel or gel beads, prepared using the process of the invention, in which the water content of the medium is 99% or more and the contact surface area of ​​the medium is increased several-fold. A condensing agent, such as an alkali, is added in small increments to achieve maximum surface area gelation. The present invention discloses two types of hydrogels based on their manufacturing method: chemical (thermosetting) gels and physical (thermoplastic) gels. Chemical gels are covalently crosslinked by different methods, such as polymerization in the presence of a crosslinking agent or crosslinking of existing polymers by different routes, such as heating, ultrasound, UV, or gamma irradiation. The present invention covers both types of hydrogels, but primarily focuses on chemical gels. Gel compositions consist of synthetic polymers such as polyethylene glycol, polyethylhydroxyethyl methacrylate, polyvinylpyrrolidone, poly N-isopropylacrylamide, and polyacrylamide, and natural polymers such as gelatin, alginic acid, chitosan, collagen, silk, cellulose, fibrin, hyaluronic acid, and agarose.

[0048] In yet another embodiment of the present invention, the present invention provides a gas absorbent that is inexpensive and easy to manufacture, which allows for a significant reduction in labor costs. Furthermore, when dissolving acidic gases, end-gel filters are often weakly alkaline, which can enhance the neutralization ability of the filter. Similarly, the acidity or alkalinity of the filter can be adjusted according to the target gas.

[0049] In another preferred embodiment, the present invention discloses a regenerative filter device consisting of a fan or vacuum system that generates negative pressure, sucking contaminated gases into the filter and dissolving and adsorbing them into the media very efficiently. Once the filter is fully saturated, a heating coil is switched on manually or automatically to evaporate the water containing the gas molecules. This water can be sent to the exhaust or collected using a condenser coil and properly discharged. Compared to wet scrubbers, the amount of water used is significantly less. Additionally, the condenser can be left on if you want to avoid increasing humidity in the discharge pump.

[0050] In yet another embodiment of the present invention, the present invention can be used in the future in the commercial sector such as airports, hospitals, data centers, schools, residential buildings etc. as well as in the industrial sector such as oil and gas industry, cement and chemical manufacturing etc.

[0051] Example

[0052] Example 1: Measuring the efficiency of air filters for reducing CO2 in indoor air One weight percent of carbomer was mixed with water and the pH was adjusted to around 5 with a few drops of a base such as sodium hydroxide or ammonium hydroxide to form a viscous gel. Separately, 10 weight percent of large 4x8 activated carbon particles was mixed with 2 wt / vol% KOH. This mixture was dried and mixed with the prepared gel to form a solid medium. The final water content in the filter was approximately 87%. This filter medium was filled into a panel filter and used to measure the efficiency of the air filter for reducing CO2 in indoor air.

[0053] The air filter was installed at a height of 1.0 m from the ground and 1.0 m away from the wall. The exposure times were 1 hour and 2.5 hours, and CO2 measurements were recorded with an analyzer after 1 hour and 2.5 hours. When 1 kg of the medium of the present invention was used, the CO2 readings were 9.81 m. 3 A 3500 ppm reduction in CO2 levels was observed in the room, equivalent to 61 g of CO2 absorption. Installing the air filter for 1 hour reduced CO2 by 40%, and installing it for 2.5 hours reduced CO2 by 65% ​​(Table 3).

[0054] [Table 3]

[0055] In other words, the media of the present invention has an absorption rate of (140 g of carbon dioxide / weight of media) / hour (140 g of CO2 / kg of media) / hr, which is far superior to the absorption rate of pure water (28 g of carbon dioxide / weight of water) / hour (28 g of CO2 / kg of water) / hr. The efficiency compared to water is 500%.

[0056] Example 2: In another experiment, a freshly regenerated filter was observed to reduce CO2 by 75% in 30 minutes, with a slight reduction in particulate levels (Table 4).

[0057] [Table 4]

[0058] Again, when the filter was regenerated with running water for 30 minutes, the CO2 concentration initially exceeded 5000 and was confirmed to have decreased by 57% in 30 minutes (Table 5).

[0059] [Table 5]

[0060] The filter was then run without regeneration media, resulting in a 22% drop in 30 minutes (Table 6).

[0061] . [Table 6]

[0062] Another version of the medium was tested, as shown below: An 85% reduction was observed at 30 minutes (Table 7).

[0063] [Table 7]

[0064] In the above regeneration, a 75% CO2 reduction was recorded in 30 minutes (Table 8).

[0065] [Table 8]

[0066] In accordance with the advantages of the present invention compared to existing scrubbers, the present invention represents a major change in the field of gas absorption from air. The filter media of the present invention is composed of gel, gel balls, activated carbon, and, depending on the gas, a mixture of zeolite and specific calcium salts capable of reacting with corrosive gases. Additionally, carbon can be added to give the material mechanical stability.

[0067] It will be further understood that the functions or structures of multiple components or steps may be combined into a single component or step, or that the functions or structures of one step or component may be split among multiple steps or components. The present invention contemplates all such combinations. Unless otherwise specified, the dimensions and shapes of various structures depicted herein are not intended to limit the present invention, and other dimensions and shapes are possible. Additionally, while features of the present invention may be described in the context of only one of the illustrated embodiments, such features may be combined with one or more other features of other embodiments for any given application. It will also be understood from the above that the creation of the unique structures herein and their operation also constitute methods in accordance with the present invention. The present invention also encompasses intermediate and final products resulting from the practice of the methods herein. The use of "comprising" or "including" also contemplates embodiments that "consist essentially of" or "cosist of" the referenced features.

[0068] Although embodiments of the present invention have been described in terms that specify structural features, it should be understood that the invention is not necessarily limited to the particular features described. Rather, the specific features and methods are disclosed as embodiments for the present invention. Numerous modifications and adaptations of the systems / components of the present invention will be apparent to those skilled in the art, and it is therefore intended by the appended claims to cover all such modifications and adaptations that fall within the scope of the present invention.

Claims

1. 1. A regenerable hydrogel filter media sorbent comprising: at least 10-50 wt / vol% of the substrate; a polymeric material for retaining water at least 0.1-1% wt / vol, with a cross-linking agent added to induce cross-linking of the polymeric material; at least 0.1-5% wt / vol of an active material to aid in gas adsorption; and At least 50-95% wt / vol water.

2. 10. The regenerable hydrogel filter media sorbent of claim 1, The substrate is at least one of carbon nanomaterials (carbon nanotubes or CNTs, graphene, nanodiamond), polymer nanoparticles (dendrimers and hyperbranched polymers), inorganic / ceramic nanoparticles (hydroxyapatite, silicates, alumina, and calcium phosphate), and metal / metal oxide nanoparticles (gold, silver, and iron oxide); The inorganic nanoparticles consist of nanohydroxyapatite (nHA), synthetic silicate nanoparticles (nanoclay), bioactive glass, silica, calcium phosphate, glass ceramics and wollastonite such as CaSiO3, and combinations thereof.

3. 10. The regenerable hydrogel filter media sorbent of claim 1, The polymeric material that retains water in the filter is at least one of synthetic polymers such as polyacrylamide, polyethylene glycol, polyethylhydroxyethyl methacrylate, polyvinylpyrrolidone, poly-N-isopropylacrylamide, and polyacrylamide, natural polymers such as gelatin, alginic acid, chitosan, collagen, silk, cellulose, fibrin, hyaluronic acid, and agarose, and combinations thereof.

4. 10. The regenerable hydrogel filter media sorbent of claim 1, The cross-linking agent is at least one of a base, such as NaOH, ammonium hydroxide, an amine, and / or radiation, such as ultrasound, UV, or gamma irradiation, and combinations thereof.

5. 10. The regenerable hydrogel filter media sorbent of claim 1, The active material that retains the corrosive gas is at least one of KOH, oxides of calcium and magnesium, and combinations thereof.

6. 1. A method for preparing a renewable hydrogel filter media sorbent, comprising: a. preparing a hydrogel component by dissolving at least 0.1-1 wt / vol% of a polymer in water; b. adding at least a cross-linking agent to induce and / or initiate cross-linking and layer thickening of the hydrogel; c. adding at least 0.1-5% wt / vol of an active material to at least 10-50% wt / vol of a base material by a mixing process to prepare an active base material; d. Sandwiching and / or mixing the thickened hydrogel from step b with the active substrate, wherein the active material is mixed with the substrate with or without a binder so that the gel composition is not disturbed upon contact, and the hydrogel and the active substrate are mixed in different ratios such as 1:1 or 10:1, and the hydrogel is sandwiched between the active substrate and a panel-type filter in layers.

7. 7. A method for preparing the regenerable hydrogel filter media adsorbent of claim 6, comprising: The hydrogel is prepared as a chemically heat-cured gel by converting a polymer-water mixture into a cross-linked gel by introducing a cross-linking agent.

8. 8. A method for preparing the regenerable hydrogel filter media adsorbent of claim 7, comprising: Said cross-linking of existing polymers can be achieved by a variety of methods, including heating, ultrasound, UV irradiation, gamma irradiation and combinations thereof, to allow for patterning of filters using a mask.

9. 7. A method for preparing the regenerable hydrogel filter media adsorbent of claim 6, comprising: Because the filter is regenerative, after treatment with corrosive gases, fresh water is added to the adsorbent of the hydrogel filter media, replenishing and regenerating the filter.

10. 11. The regenerable hydrogel filter media sorbent of claim 1 or 10, Selectivity is imparted by using a polymer network in a gel-based filter to selectively adsorb corrosive gases from the air or gas stream.

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