Porous hybrid material, method for the production thereof and use thereof as sorbent

Abstract

The invention relates to a method for producing a porous hybrid material based on plastic polymer, comprising the following steps: transferring a plastic polymer or a mixture comprising different plastic polymers into a solution with the addition of a solvent or a solvent mixture of at least two solvents; admixing one or more different functional materials; precipitating the hybrid material containing the plastic polymer or the mixture comprising different plastic polymers and the functional material or a plurality of different functional materials by adding it into a liquid and / or gaseous precipitant. The invention further relates to a porous hybrid material and to the use thereof.

Description

[0001] Porous hybrid material, a process for its production and its

[0002] Use as a sorbent

[0003] Description

[0004] The present invention relates to a method for producing a porous material. Furthermore, the present invention relates to a porous hybrid material and its use.

[0005] Every day, residues, also known as anthropogenic trace substances, from products manufactured or caused by humans continuously enter the environment. Thanks to improved analytical capabilities, it has become possible in recent years to determine their concentration in the air and, above all, in water bodies. Although these trace substances are present in very low concentrations, they have an impact on the environment and are sometimes difficult to degrade in natural waters and in the air. Furthermore, they can cause harm to organisms, including humans, which is why their elimination from water and air represents one of the greatest challenges in the coming years. This is particularly important when you consider that of the approximately 50 million chemical compounds in circulation worldwide that can therefore form trace substances, 5,000 are classified as potentially environmentally relevant.

[0006] Trace substances in waters and wastewater that can be detected in low concentrations of less than one millionth of a gram (< 1 pg / l) include, for example, active pharmaceutical ingredients, X-ray contrast agents, fragrances in personal care and cleaning products, biocides, flame retardants, perfluorinated chemicals (PFCs) and substances with hormone-like effects.

[0007] These are removed from the wastewater in sewage treatment plants. A modern sewage treatment plant treats wastewater in three stages. Primary clarification includes mechanical wastewater treatment. In this first treatment stage, larger solids are removed from the wastewater using mechanical devices such as screens and grit chambers. Wastewater treatment continues with mechanical dewatering (screening press) and subsequent disposal. The sand settles in the grit chamber. It is then mechanically washed in the grit chamber. It can then be recycled. The finer solids sink to the bottom of the primary clarifier and form sewage sludge. This flows out via pipes when it has reached a certain height in the tank. It is then dewatered and fed to the digester for recycling. The suspended solids are discharged via overflows into the second clarifier.

[0008] During the second treatment stage (biological wastewater treatment), soluble organic substances are broken down by bacteria. The degradation of feces, food scraps, and organic dirt from laundry by bacteria is only possible with the presence of oxygen. This is fed directly into the wastewater as compressed air. The bacteria digest carbon, releasing water and CO2 in the process. They also generate energy by degrading biological substances. Since they always have sufficient food, they multiply rapidly and form activated sludge. At this stage of wastewater treatment, only 5 to 10% of organic substances, phosphorus, and nitrogen compounds remain in the pre-treated water. This residue is almost completely removed from the water in the third treatment stage.

[0009] It involves the metabolization of nitrogen by certain types of bacteria. Phosphorus is eliminated through a chemical process. Aluminum chloride or iron sulfate is usually used for precipitation. These metal compounds make the phosphorus insoluble in water, causing it to sink to the bottom. It can then be disposed of. Only a few wastewater treatment plants also have a fourth treatment stage, which eliminates hormones, pesticides, herbicides, and pharmaceutical residues through the use of activated carbon. Ozone is occasionally used to kill pathogenic microorganisms and neutralize medications, with downstream activated carbon filtration. However, studies show that many of the trace substances are very difficult to remove from wastewater, and therefore a fourth treatment stage is necessary in wastewater treatment plants.

[0010] For further removal of trace substances in wastewater treatment plants through the fourth treatment stage, two main process technologies are currently available:

[0011] Ozonation: By introducing the strong oxidizing agent ozone into the pre-treated wastewater, the trace substances are largely broken down;

[0012] - Activated carbon adsorption: Trace substances can be bound to activated carbon, which is used either as powder or in granular form.

[0013] However, the fourth purification stage not only causes additional costs, but also has additional impacts on the environment in terms of energy and resource requirements and waste generation.

[0014] In addition to the natural components of the air, human-caused (anthropogenic) air pollutants such as nitrogen oxides, carbon monoxide, and sulfur dioxide can be found in the air, which can lead to long-term changes in the corresponding proportions of these components. Trace substances classified as greenhouse gases, such as methane and carbon dioxide, can also have climate-relevant impacts. Furthermore, the air contains particulate matter, which is produced by emissions from motor vehicles, power plants and district heating plants, furnaces and heating systems in residential buildings, metal and steel production, and the handling of bulk materials.

[0015] The removal of anthropogenic trace substances from the air can be achieved using mechanical, biological, or thermal processes. Biological processes degrade gaseous trace substances microbiologically. However, since the constituents must be biodegradable and can only be present in low concentrations, the application of biological processes is very limited. Biological processes are primarily used to address odor problems.

[0016] The goal of mechanical processes is to separate particles from an exhaust stream (dedusting). The separation of fine dust is particularly important.

[0017] Thermal processes are used to remove gaseous contaminants. The most common processes are absorption and adsorption. Both processes are versatile and are suitable for the removal of, for example, nitrogen oxides, sulfur dioxide, hydrogen sulfide, and carbon dioxide. A basic requirement for both processes is that the exhaust gas should be as dust-free as possible, so mechanical cleaning may be necessary first. Sorption involves at least three components: the pollutant to be separated, the carrier gas, and a solvent. The solvent absorbs the gaseous substance, which can be done physically or chemically. To ensure that the solvent only absorbs the pollutant and not the carrier gas, the solvent must be adapted to the specific application. In adsorption, the pollutant to be separated is bound to the surface of a solid (adsorbent).As with absorption, this can be achieved physically or chemically. A very commonly used adsorbent is activated carbon. Adsorption is favored by low temperatures. Therefore, the exhaust gas to be purified should not be warmer than 30°C.

[0018] Currently, as described in detail above, the focus is on activated carbon for removing trace substances from the air and wastewater. Global demand is therefore very high, and the total market volume for 2021 was estimated at approximately USD 8.13 billion. The European share for 2021 was approximately USD 1.85 billion. The main applications for activated carbon are divided into the two segments of air purification and water treatment, with air purification accounting for 41% worldwide and water treatment for another 41%. However, the activated carbon market is not environmentally friendly for various reasons.

[0019] For one thing, the manufacturing process is very energy-intensive and not particularly effective. Activated carbon is produced from plant, petrochemical, or mineral raw materials. To do this, raw activated carbon is first produced using dehydrating agents or through dry distillation. The raw activated carbon must then be further processed to give it the largest possible surface area, which, in turn, can interact with the widest possible range of substances due to its surface properties. To impart these properties to the carbon, it must be partially oxidized (partially combusted). This involves three processes:

[0020] So-called condensates, i.e., carbon compounds on the coal that are not part of the actual basic structure of the coal, are released (desorbed) and expelled. This opens "blocked" pores (especially mesopores in the pm range) of the coal, thus increasing its surface area.

[0021] A more labile fraction of the carbon backbone of the coal is burned, so that new pores are formed (especially micropores in the nanometer range).

[0022] The surface of the carbon backbone is partially oxidized, so that in addition to the aromatic backbone of the coal, functional groups (carboxyls, aldehydes, ketones) also shape the chemistry of the surface and thus make it hydrophilic (easily wettable with water).

[0023] For this purpose, the raw activated carbon is heated to high temperatures (>850°C) and treated with oxidizing gases such as air, oxygen, steam, or CO2. At these high temperatures, the unstable carbon fractions and condensates react according to the following reaction equation:

[0024] • C + O2 — CO2

[0025] . C + H2O — > CO + H2 C + CO22 CO

[0026] Activation with these gases is also referred to as "physical" activation because it was previously thought that the hot steam merely "cleaned" the coal pores. However, the process is essentially based on chemical reactions. The starting coal can be either fresh or already charred biomass, as well as hard coal or lignite. Fossil materials are often cheaper and more homogeneous.

[0027] “Chemical” activation, on the other hand, refers to the treatment of the starting material (e.g. wood, coconut shells or sugar) with chemicals such as zinc chloride or phosphoric acid, where temperatures of over 600°C must also be reached.

[0028] The process is therefore not only very complex but also not particularly effective. Producing one ton of activated carbon requires 3.5 to 5 tons of hard coal or 5 to 6.5 tons of lignite. Producing one ton of coconut fiber carbon requires 10-13 tons of coconut shells. Because the energy required for this process is so high, in practice, emissions of 11-18 tons of CO2 equivalents are generated per ton of activated carbon.

[0029] Second, the global market is dominated by suppliers from East Asia, which results in long transport routes. Second, activated carbon is usually obtained from fossil coal and is subject to fewer environmental regulations in these countries.

[0030] There are known attempts in the art to minimize the use of activated carbon in air and water purification by using plastic polymer-based materials instead of activated carbon for these purposes.

[0031] WO 2021 / 005212 discloses a method for producing a porous, plastic-polymer-based material element. This method can be used to produce elements with a (micro)porous structure that offers a large absorption surface for many pollutants. These can then replace activated carbon.

[0032] However, these materials have the disadvantage that they do not allow for targeted and selective purification of trace substances. This is because the materials disclosed in W02021 / 005212 consist exclusively of a single material. Thus, they exhibit only the properties determined by this material. Furthermore, functionalization such as sulfonation or nitration, as well as porosity modification of such materials, is limited. Furthermore, the sorption performance of such monomaterials is known to be less effective.

[0033] In view of this, the present invention is based on the object of providing new materials which, on the one hand, have a better CC>2 balance than activated carbon and, on the other hand, enable a selective removal of trace substances due to their variability and, at the same time, are economical.

[0034] This object is achieved by a method having the features of independent claim 1. Advantageous embodiments of this method are found in dependent claims 2 to 6.

[0035] Furthermore, the object underlying the invention is achieved by the porous hybrid material and by the use of the porous hybrid material.

[0036] The method according to the invention for producing a porous hybrid material comprises the following steps: a) converting a plastic polymer or a mixture comprising different plastic polymers into a solution with the addition of a solvent or a solvent mixture of at least two solvents, wherein the solvent is selected from the group comprising: inorganic acids or a mixture of different inorganic acids selected from the group comprising: sulfuric acid, nitric acid, hydrochloric acid, phosphoric acid, hydrohalic acids, hydrogen peroxide; organic acids or a mixture of different organic acids selected from the group comprising: formic acid, acetic acid; organic solvents hydrocarbons selected from the group comprising: THF, toluene, decalin;b) admixing one or more different functional materials, wherein the functional materials are selected from the list consisting of:;

[0037] 0.1 to 40 wt.% carbon-based absorbents and adsorbents,

[0038] 2 to 40 wt.% of polymeric or plastic-containing absorbents and adsorbents,

[0039] 2 to 40 wt.% of oxidic absorbents and adsorbents,

[0040] 2 to 40 wt.% of absorbents and adsorbents of biological origin selected from the group comprising: cellulose, starch, protein, chitin, chitosan-containing substances,

[0041] 2 to 50 wt.% of luminescent substances,

[0042] 0.1 to 30 wt.% indicator substances (e.g., color indicator for pH value); c) precipitating the hybrid material comprising the plastic polymer or the mixture comprising different plastic polymers and the functional material or several different functional materials by adding it to a liquid and / or gaseous precipitant. The term "hybrid material" in the sense of the present invention refers to a material that has at least two or more components according to claim 1. The components are chemically or physically bonded to one another.

[0043] For the purposes of the present invention, the term "plastic polymer" means any compound consisting of at least two or more monomers, preferably of synthetic and / or semi-synthetic origin. This term also includes reinforced polymers, e.g., with glass fiber or carbon fiber, etc.

[0044] For the purposes of the present invention, the term “polyamides” (abbreviation PA) refers to linear polymers with regularly repeating amide bonds (-CO-NH-) along the main chain, which are produced by means of polycondensation as self-condensate (PAX - X corresponds to the length of the C-skeleton, e.g. PA6) or as external condensate (PAXY: X corresponds to the length of the C-skeleton diamine; Y corresponds to the length of the C-skeleton diacid, e.g. PA6,10).

[0045] Aminocarboxylic acids, lactams, and / or diamines and dicarboxylic acids are particularly used as monomers for polyamides. Polyamides can be classified into the following classes according to the type of monomer: aliphatic polyamides: the monomers are derived from aliphatic base materials, e.g., PA from caprolactam (PA 6: see below for an explanation of the abbreviations) or from hexamethylenediamine and adipic acid (PA 66); semi-aromatic polyamides: the monomers are partly derived from aromatic base materials, e.g., PA from hexamethylenediamine and terephthalic acid (PA 6T); aromatic polyamides (polyaramides): the monomers are derived from purely aromatic base materials, e.g., para-phenylenediamine and terephthalic acid (aramid). The term “polyethylene” (abbreviation PE) in the context of the present invention means a polymer produced by polymerization of ethene with a chain structural formula [-CH2-CH2-] nA distinction is made between: PE-HD (weakly branched polymer chains with high density), PE-LD (highly branched polymer chains with low density), PE-LLD (linear low-density polyethylene whose polymer molecule has only short branches), PE-HMW (high-molecular-weight polyethylene) and PE-UHMW (ultra-high-molecular-weight polyethylene with an average molecular weight of up to 6000 kg / mol).

[0046] For the purposes of this invention, the term "polypropylene" (abbreviated PP) refers to a plastic produced by polymerizing propene. Polypropylene can be divided into atactic polypropylene, syndiotactic polypropylene, and isotactic polypropylene. In atactic polypropylene, the methyl group is randomly oriented, in syndiotactic polypropylene it is alternately oriented, and in isotactic polypropylene it is evenly oriented on one side of the macromolecular carbon backbone.

[0047] For the purposes of this invention, the term "polystyrene" (abbreviated PS) refers to a polymer produced by polymerizing the monomer styrene. The asymmetry of the styrene molecule results in different orientation options for the monomer units within the polymer molecule. These are determined by the respective polymerization conditions. A distinction is made between isotactic, syndiotactic, and atactic polymers. The isotactic styrene polymer, in which all monomer units are spatially aligned, has not achieved any industrial significance. In contrast, the amorphous, atactic styrene polymer, whose monomer units occupy random spatial positions, is the most important polystyrene plastic, used predominantly for the production of mass-produced products.

[0048] For the purposes of this invention, the term "polyurethane" (abbreviated to PUR) refers to plastics or synthetic resins resulting from the polyaddition reaction of dialcohols (diols) or polyols with polyisocyanates. Polyurethanes are characterized by the urethane group (-HN-CO-O-). For the purposes of this invention, the term "polyvinyl chloride" (abbreviated to PVC) refers to a thermoplastic polymer produced by chain polymerization from the monomer vinyl chloride.

[0049] The term "copolymer" in the context of the present invention refers to polymers composed of at least two types of monomer units. Such bi- or multifunctional copolymers can be divided into five classes: random copolymers, in which the distribution of the two monomers in the chain is random; gradient copolymers, essentially similar to random copolymers but with a variable proportion of one monomer along the chain; alternating or alternating copolymers with a repeating arrangement of the monomers along the chain; block copolymers, which consist of two longer sequences or blocks of each monomer; and graft copolymers, in which blocks of one monomer are grafted onto the backbone of another monomer. In the context of the present invention, this term also includes polymer blends consisting of multiple polymers.

[0050] The term “functional materials” in the sense of the present invention means all additives within the meaning of claim 1 which are added to the plastic polymer in order to produce the porous hybrid material according to the invention.

[0051] For the purposes of this invention, the term "adsorbents" refers to chemical substances to whose surface other substances adhere. Adhesion is achieved through physical forces of attraction, such as van der Waals forces, dipole-dipole interactions, TT-TT interactions, as well as hydrogen bonds and ionic interactions.

[0052] For the purposes of the present invention, the term "absorbents" refers to chemical substances in which another substance diffuses into the interior. For the purposes of the present invention, the term "carbon-based absorbents and adsorbents" refers to, but is not limited to, activated carbon, activated coke, carbon molecular sieves, graphite, and graphene.

[0053] The term “polymeric or plastic-containing absorbents and adsorbents” in the context of the present invention means, but is not limited to: polyamides, polystyrene, polypropylene, polyethylene, polyethylene terephthalate, polyvinyl chloride, acrylonitrile-butadiene-styrene copolymers.

[0054] The term “oxidic absorbents and adsorbents” in the context of the present invention means, but is not limited to: silicates, silica gel, activated clay, talc, zeolite, aluminum oxide, titanium dioxide.

[0055] The term “biological absorbents and adsorbents” in the context of the present invention means compounds and their derivatives which have a biological origin, but are not limited to: substances containing cellulose, starch, protein, chitin and chitosan.

[0056] The term “luminescent substances” in the context of the present invention means substances that emit light when stimulated with energy – chemical, electrical or UV light.

[0057] The term “indicator substances” in the context of the present invention means, but is not limited to: color indicator for pH value.

[0058] For the purposes of the present invention, the term “precipitant” is understood to mean an agent or a mixture of different agents intended to bring about a physical, chemical or physico-chemical reaction in which a dissolved substance reacts to form an insoluble solid.

[0059] The process according to the invention has the significant advantage of allowing rapid adaptation of the composition of the hybrid material for new applications. Compared to the monomaterials known from the prior art, the porous hybrid materials obtained according to the process according to the invention have the significant advantage of being characterized by high variability and flexibility in their possible applications. By selecting the functional material, the hybrid material can be specifically manufactured for its end application. For example, the hybrid materials according to the invention can be manufactured in such a way that they very selectively absorb one or more trace substances. This selectivity is becoming increasingly important, particularly for applications in the fields of medicine or food technology.

[0060] Furthermore, the flexibility of such a hybrid material to adapt to new trace substances is of great importance, especially given the continuously increasing number of trace substances found in wastewater and the air. With the hybrid materials according to the invention, this can be achieved simply by replacing the respective functional material.

[0061] Furthermore, the hybrid material obtained according to the process of the invention has a significantly better carbon-carbon balance than activated carbon. As explained in detail above, activated carbon is very complex to produce, and its production and activation require a lot of energy, resulting in very high CO2 emissions. The production of the hybrid material according to the present invention is considerably more environmentally friendly. This results from the fact that most applications of the hybrid material use plastic waste and / or recycled products as starting materials, including plastic waste and / or recycled products that have not undergone prior purification.

[0062] This significantly increases the environmental compatibility of the hybrid materials according to the invention.

[0063] Only for applications subject to extremely stringent requirements, such as the medical field, are plastic waste and / or recycled products not used as raw materials. However, even when new plastic polymers are used, their production is not as energy-intensive as the production of activated carbon.

[0064] Furthermore, due to the polymer matrix, the hybrid materials according to the invention are characterized by a higher calorific value during combustion (such as in waste incineration plants) or pyrolysis compared to activated carbon. This can also have a positive impact on the energy balance.

[0065] According to one embodiment of the invention, the solvent is an acid selected from the group consisting of: hydrochloric acid, sulfuric acid, nitric acid, formic acid, acetic acid, preferably hydrochloric acid and sulfuric acid.

[0066] According to a further embodiment of the invention, the solvent is an organic solvent selected from the group comprising: THF, toluene, decalin.

[0067] According to one embodiment of the invention, the solvent is a mixture comprising sulfuric acid and hydrogen peroxide in a ratio of 4 to 1.

[0068] According to one embodiment of the invention, the solvent is a mixture comprising 96% sulfuric acid and 30% hydrogen peroxide in a ratio of 4 to 1.

[0069] According to a further embodiment of the invention, the concentration of the aqueous acid is at least 10% and at most 99%. According to a preferred embodiment, the concentration is 16% to 96%.

[0070] The selection of the solvent or mixture comprising different solvents must be such that separation steps are also achieved. This is particularly important when using unpurified and / or non-segregated waste as the starting material.

[0071] According to a further embodiment of the invention, the ratio of the plastic polymer or the mixture comprising different plastic polymers to the solvent is from 5:100 to 60:100. In detail, the ratio of the plastic polymer or the mixture comprising different plastic polymers is from 5 g to 100 g of the solvent to 60 g of the plastic polymer or the mixture comprising different plastic polymers to 100 g of the solvent.

[0072] The admixture of one or more different functional materials can be carried out in various ways. Only two possibilities are described here as examples. However, the invention is not limited to these. On the one hand, the admixture of the functional material(s) can be carried out after step a) by stirring or kneading, depending on the viscosity of the solution present. On the other hand, the admixture can also take place during step a).

[0073] According to a further embodiment of the invention, the amount of the functional material or mixture is 0.1 to 60 wt.%, preferably 0.2 to 45 wt.%, more preferably 0.5 to 25 wt.%. According to a further embodiment, the amount of the one or more different functional materials is 10 to 20 wt.%, preferably 10 to 15 wt.%.

[0074] The precipitation of the hybrid material according to step c) can, for example, be carried out by converting the polymer additive solution into a precipitant and thereby precipitating it.

[0075] According to one embodiment, the precipitant is selected from the list comprising: water, acids, bases, and mixtures thereof. The precipitant can be in liquid or vapor form.

[0076] The precipitant is preferably water. This has the advantage that the process according to the invention is extremely safe and cost-effective.

[0077] More preferably, the precipitant is selected from the list comprising aqueous solutions of NaOH, Ca(OH)2, KOH, HCl, and H2SO4. According to one embodiment, precipitation is achieved by addition to a liquid and / or gaseous precipitant. According to this embodiment, the solution obtained in step b) is added dropwise, poured, stirred, immersed, or sprayed (e.g., using nozzles) into the vessel containing the precipitant in portions. If the precipitant is gaseous, it is added in a vaporization / gasification chamber. In this case, the gaseous precipitant can already be present in a defined concentration or can be iteratively adjusted to the desired concentration (saturation). The duration of incubation in the gaseous precipitant depends on various parameters (e.g., thickness of the material, temperature, material shape, hydrophobicity / hydrophilicity, porosity).

[0078] According to a further embodiment, after step b), the solution comprising the plastic polymer or the mixture comprising different plastic polymers and the functional material or several different functional materials is gassed with an inert gas or foamed using substances capable of gas formation. This additional step achieves an open-cell and / or closed-cell or mixed-cell structure, thereby increasing the volume of the material and thus reducing weight. In this case, the solution can be gassed with an inert gas so that this gas is widely distributed throughout the mass (during a mixing process). If this gassing is carried out in a suitable pressure-stable container, a volume increase is achieved, for example into a precipitant-permeable shape (e.g., cylinder), if the pressure is maintained.By introducing a liquid or gaseous precipitant (e.g. water or steam) into the pressure vessel to the foamed mass, the foam is stabilized by the slow phase separation of the solvent and precipitant in the precipitant-permeable (e.g. semi-permeable membrane) form and can be removed after a time. When using a substance capable of gas formation or a coated (delayed release) substance capable of gas formation, the mass can also be foamed and stabilized by a liquid or gaseous precipitant through the triggered phase separation. According to one embodiment, the porous hybrid material comprises 0.1 to 60 wt. %, preferably 0.2 to 45 wt. %, more preferably 0.5 to 25 wt. % of the one or more different functional materials. According to one embodiment, the porous hybrid material comprises 10 to 20 wt. %, preferably 10 to 15 wt.-% of one or more different functional materials. This measure has the significant advantage that the porous hybrid material is cost-effective, but at the same time, as the studies have shown, exhibits improved effectiveness.

[0079] According to a further embodiment, the plastic polymer is polyamide-6, polyamide-6.6 or polyamide-12, particularly preferred is polyamide-6.

[0080] According to a further embodiment, the plastic polymer is made from plastic waste and / or recycled products.

[0081] According to a further embodiment, the plastic polymer is made from plastic waste and / or recycled products that have not been subjected to prior cleaning.

[0082] According to a further embodiment, the functional material is selected from the group consisting of: activated carbon, activated coke, carbon molecular sieves, graphite, graphene, preferably from activated carbon, carbon molecular sieves and graphene and most preferably activated carbon.

[0083] According to a further embodiment, the functional material is selected from the group consisting of: polystyrene, polypropylene, polyethylene, polyethylene terephthalate, acrylonitrile-butadiene-styrene copolymers, preferably from polystyrene, polypropylene, polyethylene, acrylonitrile-butadiene-styrene copolymers, most preferably polystyrene and acrylonitrile-butadiene-styrene copolymers.

[0084] According to a further embodiment, the functional material is selected from the group consisting of: silicates, silica gel, activated clay, talc, zeolite, aluminum oxide, titanium dioxide, preferably from silicates, silica gel, zeolite, and titanium dioxide, most preferably silicates and titanium dioxide. The use of titanium dioxide has the significant advantage that such hybrid materials according to the invention exhibit photocatalytic properties and thus the utilization of light, in particular sunlight, to increase the elimination of pollutants and trace substances.

[0085] According to a further embodiment, the functional material is selected from the group consisting of: cellulose, chitin, chitosan, preferably from cellulose and chitin.

[0086] According to a further embodiment, the functional material is a luminescent substance, for example strontium aluminate.

[0087] According to a further embodiment, the functional material is a color indicator for pH value.

[0088] It is also within the meaning of the present invention that the respective groups of the different functional materials can be present together in a hybrid material.

[0089] In one embodiment of the invention, the distribution of the functional material or materials is approximately homogeneous. This means that the materials are evenly distributed throughout the final product.

[0090] According to a further embodiment, the hybrid material according to the invention is in the form of granules, drops, spheres, membranes, foams or filaments.

[0091] The granules range in size from 0.1 mm to 20 mm, preferably 0.2 mm to 5 mm. They can be shaped as drops or spheres. The granular form has the advantage that, due to its free-flowing properties, they can be transported like bulk materials such as sand or gravel, making them just as easy to transport.

[0092] In the context of the present invention, the term “membrane” refers to polymer structures whose thickness is very small in relation to their areal extent.

[0093] In the context of the present invention, the term “foams” refers to polymer structures whose structure is formed by many cells (cavities, pores enclosed by the base material).

[0094] For the purposes of the present invention, the term “filaments” refers to polymer structures consisting of continuous fibers that form a flexible structure.

[0095] According to a further embodiment, the porous hybrid material has pores with a size of 0.001 pm to 3000 pm. Preferably, the pores have a size of 0.001 pm to 200 pm. More preferably, the pores have a size of 0.001 pm to 50 pm. Even more preferably, the pores have a size of 0.001 pm to 20 pm. Most preferably, the pores have a size of 0.001 pm to 10 pm. The measurement method for the specific surface area is gas adsorption according to DIN ISO 9277 (or DIN 66131) using the Brunauer-Emmett-Teller method (BET method).

[0096] In one embodiment of the invention, the porous hybrid material is completely open-pored. In a further embodiment of the invention, the porous hybrid material is partially open-pored. In the context of the present invention, this means that some pores of the hybrid material are open and some are closed. In the case of the foams according to the invention, one speaks of cells rather than pores (open-cell or mixed-cell foams). In one embodiment of the invention, the porous hybrid material comprises the following: a) at least 40 wt. % of a plastic polymer or a mixture comprising different plastic polymers selected from the group consisting of polyamides, polyethylene, polypropylene, polystyrene, polyurethane, polyvinyl chloride, and copolymers of the aforementioned; and b)

[0097] 0.1 to 40 wt.% carbon-based absorbents and adsorbents, and / or

[0098] 2 to 40 wt.% of polymeric or plastic-containing absorbents and adsorbents, and / or

[0099] 2 to 40 wt.% of oxidic absorbents and adsorbents, and / or

[0100] 2 to 40% by weight of absorbents and adsorbents of biological origin selected from the group comprising: cellulose-, starch-, protein-, chitin-, chitosan-containing substances; and / or

[0101] 2 to 50 wt.% of luminescent substances, and / or

[0102] 0.1 to 30 wt.% indicator substances (e.g. color indicator for pH value).

[0103] In one embodiment of the invention, the porous hybrid material comprises: a) at least 40 wt.% of a polyamide; and b)

[0104] 0.1 to 40 wt.% carbon-based absorbents and adsorbents, and / or

[0105] 2 to 40 wt.% of polymeric or plastic-containing absorbents and adsorbents, and / or

[0106] 2 to 40 wt.% of oxidic absorbents and adsorbents, and / or

[0107] 2 to 40% by weight of absorbents and adsorbents of biological origin selected from the group comprising: cellulose-, starch-, protein-, chitin-, chitosan-containing substances; and / or 2 to 50% by weight of luminescent substances, and / or

[0108] 0.1 to 30 wt.% indicator substances (e.g. color indicator for pH value).

[0109] In one embodiment of the invention, the porous hybrid material comprises the following: a) at least 40 wt.% PA6, PA66, PA12; and b)

[0110] 0.1 to 40 wt.% carbon-based absorbents and adsorbents, and / or

[0111] 2 to 40 wt.% of polymeric or plastic-containing absorbents and adsorbents, and / or

[0112] 2 to 40 wt.% of oxidic absorbents and adsorbents, and / or

[0113] 2 to 40% by weight of absorbents and adsorbents of biological origin selected from the group comprising: cellulose-, starch-, protein-, chitin-, chitosan-containing substances; and / or

[0114] 2 to 50 wt.% of luminescent substances, and / or

[0115] 0.1 to 30 wt.% indicator substances (e.g. color indicator for pH value).

[0116] In one embodiment of the invention, the porous hybrid material comprises the following: a) at least 40 wt.% of a polyamide, b) 2 to 40 wt.% of polymeric or plastic-containing absorbents and adsorbents.

[0117] In one embodiment of the invention, the porous hybrid material comprises the following: a) at least 40 wt.% PA6, PA66, PA12; b) 2 to 40 wt.% of polymeric or plastic-containing absorbents and adsorbents. In one embodiment of the invention, the porous hybrid material comprises 0.1 to 20 wt.% graphene as adsorbents b).

[0118] In one embodiment of the invention, the porous hybrid material comprises 5 to 40 wt.% activated carbon as adsorbents b).

[0119] The hybrid material according to the invention can be used for the following applications, but is not limited to these: as a sorbent for trace substances in water and air purification; as a growth and nutrient matrix for microorganisms; as a filling and insulating material due to its flame-retardant potential; as a substitute for weight reduction, for example in the automotive sector or in the aviation industry for lightweight construction. The use as a sorbent for trace substances in water and air purification was described in detail at the beginning. When used as a growth and nutrient matrix for microorganisms, the hybrid materials according to the invention are produced according to the process in a suitable form (membrane or spheres) for the application. A phosphorescent substance (strontium aluminate) is added as a functional material for the hybrid production.These particles are then added to an illuminated bioreactor and colonized by the targeted microorganisms, such as (micro)algae. The hybrid materials according to the invention serve as surface enlargers and growth matrixes for the microorganisms in the reactor. Suitable illumination of the entire bioreactor is complex, and the incident light cannot be fully utilized. The phosphorescent substances in the adsorbers store excess light and can release it back into the environment over a certain period of time to supply the microorganisms. This allows for the development of energy-saving processes (intermittent irradiation) for the bioreactor, which is accompanied by a sustained active metabolism of the microorganisms, such as (micro)algae, over a longer period.Through specific compositions of hybrid materials according to the invention, further advantages for applications can be integrated, such as medium-stabilizing substances or selective substances for the adsorption and / or adsorption of toxic metabolic products of microorganisms.

[0120] When used as filling and insulating materials due to their flame-retardant potential or as substitutes for weight reduction, for example in the automotive or aerospace sectors for lightweight construction, the hybrid materials are produced using the process according to the invention. The open- and / or closed-pore or mixed-pore foams can be used for thermal insulation in buildings, for example. The open-pore structure also enables gas and water vapor exchange. The polymer foams can also be used as sound insulation or impact or impact insulation. In addition, the porous structure reduces the weight of the material, which can be advantageous in the automotive and aerospace industries.

[0121] Further advantageous properties of the invention are described and explained in more detail below using examples and experiments.

[0122] List of abbreviations Example 1 : Production of the monomaterial APA6

[0123] APA6 was prepared according to the method disclosed in W02021005212 using 48 g of polyamide-6 and 100 ml of 20% hydrochloric acid.

[0124] Example 2: Production of the hybrid material APAK6

[0125] To produce the A PA K6 material, 100 ml of 20% hydrochloric acid was placed in a beaker. 43.2 g of PA6 (polyamide 6), obtained as waste chips from a plastics and metal machining operation, were then weighed and added to the 20% hydrochloric acid under standard conditions while stirring manually using a Teflon rod, to form a polymer solution. It was particularly evident that the provided plastic polymer also contained stainless steel and aluminum chips, which could be easily separated by density separation in a later step. After the PA6 waste material had completely dissolved, 4.8 g of powdered activated carbon were added as a functional material while stirring to obtain a 48 g material mixture consisting of 90 wt% polymer and 10 wt% functional materials.The solution was stirred until the activated carbon appeared to be evenly distributed throughout the polymer solution. The polymer solution was transferred through a PP (polypropylene) mesh (0.2 mm mesh size) into another beaker to separate the aluminum and metal shavings. In the next step, a 3,000 ml measuring beaker was filled with 2,500 ml of precipitant (tap water, approximately 14°C) as a storage container. The tap water was rotated on a magnetic stirrer plate at approximately 700 rpm until a vortex formed. The polymer solution containing the functional material was taken up with a 10 ml Pasteur pipette and added dropwise to the tap water at a distance of approximately 12 cm above the fill level, thereby causing precipitation.The resulting granules (APAK6) exhibit a stable and consistently porous structure, with the powdered activated carbon particles evenly embedded in a porous polymer matrix. Since the precipitant shifts into the acidic pH range with increasing proportion of the acidic polymer solution, neutralization with an alkali, depending on the amount of polymer solution, is recommended, and the spheres are then sieved. The sieved granules are washed in another measuring beaker with tap water to remove most of the acid and salt residues, then sieved again and dried in the ambient air.

[0126] Example 3: Production of monomaterial APA12

[0127] APA12 was prepared according to the method disclosed in W02021005212 using 16 g of polyamide-12 and 100 ml of 96% sulfuric acid.

[0128] Example 4: Production of the hybrid material APAK12

[0129] To produce the APAK12 material, 100 ml of 96% sulfuric acid was placed in a beaker. 14.4 g of PA12 (polyamide 12), in the form of sprue parts that arise as waste from a plastics injection molding plant, were then weighed and added to the 96% sulfuric acid under standard conditions while stirring manually using a Teflon rod, to create a polymer solution. It was particularly evident that the provided plastic polymer also contained metal parts such as screws and nuts, which could, however, be easily removed in a later step using density separation. After the PA12 waste material had completely dissolved, 1.6 g of powdered activated carbon was added as a functional material while stirring to produce a 16 g material mixture consisting of 90 wt% polymer and 10 wt% functional materials.The solution was stirred until the activated carbon appeared to be evenly distributed throughout the polymer solution. The polymer solution was transferred through a PP (polypropylene) mesh (0.2 mm mesh size) into another beaker to separate the metal particles. In the next step, a 3,000 ml measuring beaker was filled with 2,500 ml of precipitant (tap water, approx. 14°C) as a storage container. The tap water was rotated on a magnetic stirrer plate at approx. 700 rpm until a vortex formed. The polymer solution containing the functional material was picked up with a 10 ml Pasteur pipette and added dropwise to the tap water at a distance of approx. 12 cm above the fill level, thereby causing precipitation. The resulting granules (APAK12) have a stable and consistently porous structure in which the particles of powdered activated carbon are uniformly embedded in a porous polymer matrix.Since the precipitant shifts into the acidic pH range with increasing proportion of the acidic polymer solution, it should be neutralized with an alkali, depending on the amount of polymer solution, and the spheres should then be sieved. The sieved granules are rinsed in another measuring beaker with tap water to remove most of the acid and salt residues, then sieved again and dried in the ambient air.

[0130] Example 5: Production of the hybrid material APA6 / Bentonite

[0131] To produce the APA6 / bentonite material, 100 ml of 44% sulfuric acid was placed in a beaker. 44 g of PA6 (polyamide 6), obtained as waste chips from a plastics and metal machining operation, were then weighed and added to the 44% sulfuric acid under standard conditions while manually stirring with a Teflon rod, resulting in a viscous polymer solution. It was particularly evident that the prepared plastic polymer also contained stainless steel and aluminum chips, which could be easily separated using density separation in a later step. After the PA6 waste material had completely dissolved, 4.89 g of bentonite powder were added as a functional material while stirring to achieve a 48.89 g material mixture consisting of 90 wt% polymer and 10 wt% functional materials.The solution was stirred until the bentonite appeared to be evenly distributed throughout the polymer solution. In the next step, a 3,000 ml measuring beaker was filled with 2,500 ml of precipitant (tap water at approximately 18°C) as a storage container. A magnetic stir bar was used to rotate the tap water on a magnetic stirrer plate at approximately 700 rpm until a vortex formed. The polymer solution containing the functional material was taken up with a 10 ml Pasteur pipette and added dropwise to the tap water at a distance of approximately 12 cm above the fill level, causing it to precipitate. The resulting granules (APA6 / bentonite) exhibit a stable and consistently porous structure, with the bentonite particles evenly embedded in a porous polymer matrix. The reaction with the 44% sulfuric acid imparts an even more porous structure to the bentonite.This increases the specific surface area of ​​the plastic granules. Since the precipitant shifts into the acidic pH range with increasing proportion of the acidic polymer solution, the granules should be neutralized with an alkali, depending on the amount of polymer solution, and then sieved. The sieved granules are rinsed in another measuring beaker with tap water to remove most of the acid and salt residues, then sieved again and dried in the ambient air.

[0132] Example 6: Production of porous ABS particles with hydrated lime

[0133] To produce the porous ABS granules, 50 ml of acetone was placed in a beaker. 17.5 g of ABS ground material was then weighed and added to the acetone under standard conditions while stirring manually with a Teflon rod, resulting in a viscous polymer solution. After the ABS ground material had completely dissolved, 1.94 g of hydrated lime powder was added as a functional material while stirring to achieve 19.44 g of a material mixture consisting of 90 wt% polymer and 10 wt% functional materials. The solution was stirred until the hydrated lime appeared to be evenly distributed throughout the polymer solution. In the next step, a 1,000 ml measuring beaker was filled with 800 ml of precipitant (tap water and ethanol in a ratio of 6:4 at approximately 20°C). Using a magnetic stir bar, the precipitant was rotated on a magnetic stirrer plate at approximately 700 rpm until a vortex formed.The polymer solution containing the functional material was collected using a 10 ml Pasteur pipette and dropped into the tap water at a distance of approximately 8 cm above the fill level, causing it to precipitate. The resulting granules (ABS / hydrated lime) exhibit a stable and consistently porous structure, in which the hydrated lime particles are uniformly embedded in a porous polymer matrix. The sieved granules were washed in another measuring beaker with tap water to remove most of the precipitant residue. The granules were then washed in a 20% hydrochloric acid solution to convert the hydrated lime into readily water-soluble calcium chloride. Finally, the granules were washed again in water to dissolve the calcium chloride from the porous structure. This generated an increased specific surface area for the particles.

[0134] Experiment 1: Adsorption experiments

[0135] 120 ml of synthetic wastewater (according to DIN EN ISO 11733) with the starting concentrations listed in Table 1 were treated with 2.5 g of each of the four adsorbents (APA12, APAK12, APA6, and APAK6) for 10 hours at room temperature. The adsorbents were packed in a fixed-bed reactor in 35 ml glass chromatography columns. A peristaltic pump circulated the synthetic wastewater through the fixed-bed reactors at a flow rate of 6 ml / min. Trace analysis was performed using LC-MS / MS.

[0136] Table 1 : Comparison of the elimination performance between APA12 and APAK12, and APA6 and APAK6.

[0137] As can be clearly seen from Table 1, the adsorption performance of the hybrid materials APAK6 and APAK12 is significantly higher in all cases than the adsorption performance of the corresponding monomaterials APA6 and APA12. The residual concentration of the respective trace elements is considerably lower in the hybrid materials according to the invention, in extreme cases by a factor of 60.

[0138] Table 2: Comparison of the percentage elimination performance between APA12 and APAK12, and APA6 and APAK6.

[0139] Table 2 shows the results of Table 1, but based on the elimination in %. It is also clear that the hybrid materials according to the invention exhibit a significantly higher degree of elimination.

Claims

Claims: A process for producing a porous hybrid material based on a plastic polymer, comprising the following steps: a) converting a plastic polymer or a mixture comprising different plastic polymers into a solution by adding a solvent or a solvent mixture of at least two solvents, wherein the solvent is selected from the group comprising: inorganic acids or a mixture of different inorganic acids selected from the group comprising: sulfuric acid, nitric acid, hydrochloric acid, phosphoric acid, hydrohalic acids, hydrogen peroxide; organic acids or a mixture of different organic acids selected from the group comprising: formic acid, acetic acid; organic solvents hydrocarbons selected from the group comprising: THF, toluene, decalin;b) Addition of one or more different functional materials, wherein the functional materials are selected from the list consisting of:; 0.1 to 40 wt.% carbon-based absorbents and adsorbents, 2 to 40 wt% of polymeric or plastic-containing absorbents and adsorbents, 2 to 40 wt% of oxide absorbents and adsorbents, 2 to 40 wt% of absorbents and adsorbents of biological origin selected from the group comprising: cellulose-, starch-, protein-, chitin-, and chitosan-containing substances, 2 to 50 wt% of luminescent substances, 0.1 to 30 wt% indicator substances (e.g., color indicator for pH value); c) precipitation of the hybrid material comprising the plastic polymer or the mixture comprising different plastic polymers and the functional material or several different functional materials by addition to a liquid and / or gaseous precipitating agent. A method according to claim 1, characterized in that the functional material is a carbon-based adsorbent or absorbent comprising all types of carbon, activated carbon, activated coke, graphite, or graphene. A method according to claim 1, characterized in that the functional material is an oxide adsorbent or absorbent. A method according to claim 1, characterized in that the functional material is a polymeric or plastic-containing adsorbent or absorbent.Method according to one of claims 1 to 4, characterized in that the solvent is an inorganic acid or a mixture of different inorganic acids selected from the group comprising: sulfuric acid, nitric acid, hydrochloric acid, hydrohalic acids. A method according to any one of claims 1 to 5, characterized in that, after step b), the solution comprising the plastic polymer or the mixture comprising different plastic polymers and the functional material or several different functional materials is aerated with an inert gas or foamed by using gas-generating substances. A porous hybrid material comprising: a) at least 40 wt.% of a plastic polymer or a mixture comprising different plastic polymers selected from the group consisting of polyamides, polyethylene, polypropylene, polystyrene, polyurethane, polyvinyl chloride, and copolymers of the aforementioned; and b) 0.1 to 40 wt% carbon-based absorbents and adsorbents, and / or 2 to 40 wt% of polymeric or plastic-containing absorbents and adsorbents, and / or 2 to 40 wt% of oxide absorbents and adsorbents, and / or 2 to 40% by weight of absorbents and adsorbents of biological origin selected from the group comprising: cellulose-, starch-, protein-, chitin-, and chitosan-containing substances; and / or 2 to 50 wt% of luminescent substances, and / or 0.1 to 30 wt% indicator substances (e.g. color indicator for pH value). Porous hybrid material according to claim 7, characterized in that it comprises: a) at least 40 wt.% of a polyamide; and b) 0.1 to 40 wt% carbon-based absorbents and adsorbents, and / or 2 to 40 wt% of polymeric or plastic-containing absorbents and adsorbents, and / or 2 to 40 wt% of oxide absorbents and adsorbents, and / or 2 to 40% by weight of absorbents and adsorbents of biological origin selected from the group comprising: cellulose-, starch-, protein-, chitin-, and chitosan-containing substances; and / or 2 to 50 wt% of luminescent substances, and / or 0.1 to 30 wt.% indicator substances (e.g., color indicator for pH value). Porous hybrid material according to claim 7 or 8, characterized in that it comprises: a) at least 40 wt.% PA6, PA66, PA12; and b) 0.1 to 40 wt% carbon-based absorbents and adsorbents, and / or 2 to 40 wt% of polymeric or plastic-containing absorbents and adsorbents, and / or 2 to 40 wt% of oxide absorbents and adsorbents, and / or 2 to 40% by weight of absorbents and adsorbents of biological origin selected from the group comprising: cellulose-, starch-, protein-, chitin-, and chitosan-containing substances; and / or 2 to 50 wt% of luminescent substances, and / or 0.1 to 30 wt% indicator substances (e.g. color indicator for pH value). A porous hybrid material according to any one of claims 7 to 9, characterized in that it comprises: a) at least 40 wt.% of a polyamide; b) 2 to 40 wt.% of polymeric or plastic-containing absorbents and adsorbents. A porous hybrid material according to any one of claims 7 to 10, characterized in that it comprises: a) at least 40 wt.% PA6, PA66, PA12; b) 2 to 40 wt.% of polymeric or plastic-containing absorbents and adsorbents. A porous hybrid material according to any one of claims 7 to 11, characterized in that it comprises 0.1 to 20 wt.% graphene as adsorbents b). A porous hybrid material according to any one of claims 7 to 11, characterized in that it comprises 5 to 40 wt.% activated carbon as adsorbents b). Use of a hybrid material according to one of claims 7 to 13 as an adsorbent and absorber of trace substances in water and air purification.Use of a hybrid material according to any one of claims 7 to 13 as a growth and nutrient matrix for microorganisms. Use of a hybrid material according to any one of claims 7 to 13 as a filling and insulating material or as a substitute for weight reduction.

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