A composite foamed polyurethane material and its application

Abstract

This invention relates to the field of polyurethane materials technology, providing a composite foamed polyurethane material and its applications. The composite foamed polyurethane material consists of component A and component B. Component A contains di(hydroxyalkyl)anthraquinone, and component B is a polyisocyanate compound, wherein the polyisocyanate compound contains anthraquinone with a chemically bonded weight percentage of not less than 5%. This invention introduces anthraquinone structures into the foamed polyurethane material through two methods, and simultaneously adds carbon-based materials, which can fully utilize the role of anthraquinone as a redox mediator in promoting denitrification of nitrogenous wastewater, and also exhibits high mechanical strength and durability.

Description

Technical Field

[0001] This invention belongs to the field of polyurethane materials technology, and relates to a composite foamed polyurethane material and its applications. Background Technology

[0002] Industrial and agricultural activities, as well as daily life, generate large amounts of nitrogen-containing wastewater. This wastewater contains both inorganic and organic nitrogen, which can have significant negative impacts on ecosystems and human lives. Microbial anaerobic denitrification is an effective method for treating nitrogen-containing wastewater. Adding redox mediators can improve denitrification efficiency; anthraquinone compounds are commonly used redox mediators. However, anthraquinone compounds are mostly water-soluble and easily washed away, causing secondary pollution. Existing technologies report various methods for dispersing anthraquinone compounds within a carrier or grafting them onto its surface. Commonly used polymer-type carriers include polyethylene, polypropylene, and polyurethane. From a practical application perspective, it is desirable for the carrier to be suspended in the wastewater. For polyurethane carriers, whose density is greater than that of wastewater, a foamed polyurethane is generally required. Besides requiring good loading capacity for anthraquinone compounds, the carrier also needs high mechanical strength and good stability to achieve a sustained denitrification-promoting effect.

[0003] In the prior art, one method for loading anthraquinone onto polyurethane is to react aminoanthraquinone or hydroxyanthraquinone with NCO groups and use them as isocyanate curing agents. However, due to the relatively low reactivity of the amino or hydroxyl groups on anthraquinone, and the significant steric hindrance caused by the large volume of anthraquinone, the effect of anthraquinone being chemically dispersed on polyurethane is affected. For example, if the content of anthraquinone in polyurethane is too low, a good denitrification promoting effect cannot be achieved.

[0004] Therefore, existing foamed polyurethane as a carrier for anthraquinone compounds needs further improvement and optimization. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a composite foamed polyurethane material and its applications.

[0006] The technical solution of the present invention is as follows:

[0007] A composite foamed polyurethane material, composed of component A and component B;

[0008] The raw material components of component A include: 100 parts polymer diol, 0.5-3 parts di(hydroxyalkyl)anthraquinone, 1-8 parts chain extender, 1-3 parts catalyst, 0-5 parts crosslinking agent, 0.1-2 parts carbon-based material, and 0.5-2 parts water;

[0009] The di(hydroxyalkyl)anthraquinone is selected from one or a combination of two or more of 1,4-bis[(hydroxyethyl)amino]anthraquinone, 1-[(2-hydroxyethyl)amino]-4-[(3-hydroxypropyl)amino]anthraquinone, 1,4-bis[(hydroxypropyl)amino]anthraquinone, 2,5-bis[(hydroxypropyl)amino]anthraquinone, 1,8-bis[(hydroxypropyl)amino]anthraquinone, 2,5-bis[(hydroxyethyl)amino]anthraquinone, 2,6-bis[(hydroxyethyl)amino]anthraquinone and 2,6-bis[(hydroxypropyl)amino]anthraquinone;

[0010] Component B is a polyisocyanate compound;

[0011] The polyisocyanate compound contains 5-15% anthraquinone by weight in chemical bonding.

[0012] Preferably, the NCO content of the polyisocyanate compound is not less than 10 wt%.

[0013] Preferably, the polyisocyanate compound is obtained by reacting reactants containing diaminoanthraquinone and diisocyanate monomers.

[0014] More preferably, the diaminoanthraquinone is selected from one or a combination of two or more of 1,2-diaminoanthraquinone, 1,4-diaminoanthraquinone, 1,8-diaminoanthraquinone, 2,5-diaminoanthraquinone and 2,6-diaminoanthraquinone.

[0015] More preferably, the diisocyanate monomer is selected from one or a combination of two or more of HDI, HMDI, XDI, MDI, TMXDI, IPDI, NDI and TDI.

[0016] More preferably, the reaction raw materials further include polyether polyols;

[0017] The molar ratio of the polyether polyol to the diaminoanthraquinone is 0.5-3:1.

[0018] Preferably, the catalyst is selected from dihydroxyalkylamine;

[0019] The crosslinking agent is selected from triethanolamine or triisopropanolamine;

[0020] The carbon-based material is selected from one or a combination of two or more of carbon nanotubes, graphene, and graphene oxide.

[0021] More preferably, the carbon-based material has one or more of primary amino groups, secondary amino groups, and hydroxyl groups chemically bonded to its surface.

[0022] Preferably, the molar ratio of active hydrogen in component A to NCO groups in component B is 1:1.08-1.2.

[0023] The application of the composite foamed polyurethane material described in any of the above embodiments in the treatment of nitrogen-containing wastewater.

[0024] The beneficial effects of this invention are as follows: This invention introduces anthraquinone structures into polyurethane through two methods: ① Some anthraquinones are chemically bonded to the polyisocyanate compound used as a curing agent; ② Di(hydroxyalkyl)anthraquinone is added to component A of the raw material. The hydroxyl groups of the hydroxyalkyl group are less sterically hindered by the alkylene structure separating them from the anthraquinone structure, resulting in higher reactivity. Therefore, this invention achieves better chemical bonding and dispersion of the anthraquinone structure in foamed polyurethane. While leveraging the redox mediator function of anthraquinone, the large volume and two carbonyl groups of the anthraquinone structure increase the hydrogen bonds in the hard segments of the polyurethane, which is more conducive to achieving microphase separation between the soft and hard segments of the polyurethane, thereby improving the mechanical strength and durability of the polyurethane. Detailed Implementation

[0025] The technical solution of the present invention will be further explained and described below through specific embodiments.

[0026] On the one hand, the present invention proposes a composite foamed polyurethane material, which is composed of component A and component B;

[0027] The raw material components of component A include: 100 parts polymer diol, 0.5-3 parts di(hydroxyalkyl)anthraquinone, 1-8 parts chain extender, 1-3 parts catalyst, 0-5 parts crosslinking agent, 0.1-2 parts carbon-based material, and 0.5-2 parts water;

[0028] Di(hydroxyalkyl)anthraquinone is selected from one or a combination of two or more of 1,4-bis[(hydroxyethyl)amino]anthraquinone, 1-[(2-hydroxyethyl)amino]-4-[(3-hydroxypropyl)amino]anthraquinone, 1,4-bis[(hydroxypropyl)amino]anthraquinone, 2,5-bis[(hydroxypropyl)amino]anthraquinone, 1,8-bis[(hydroxypropyl)amino]anthraquinone, 2,5-bis[(hydroxyethyl)amino]anthraquinone, 2,6-bis[(hydroxyethyl)amino]anthraquinone and 2,6-bis[(hydroxypropyl)amino]anthraquinone;

[0029] Component B is a polyisocyanate compound;

[0030] Anthraquinones, chemically bonded to 5-15% by weight in polyisocyanate compounds.

[0031] This invention uses foamed polyurethane as a carrier to chemically bond anthraquinone onto the polyurethane, thereby improving the dispersibility and stability of anthraquinone, giving full play to the denitrification promoting effect of anthraquinone and improving the mechanical strength of polyurethane.

[0032] Due to the steric hindrance and electron-withdrawing effects caused by the large volume of the anthraquinone structure, the amino or hydroxyl groups directly bonded to the anthraquinone structure have relatively low reactivity, which affects the reactivity with NCO groups, such as resulting in a low content of the introduced anthraquinone structure. In this invention, anthraquinone is chemically bonded to polyurethane in two ways: part of the anthraquinone is chemically bonded to the curing agent polyisocyanate compound, and the other part of the anthraquinone participates in the reaction of polyurethane in component A. This has the following characteristics: ① the anthraquinone content in the polyisocyanate compound is low, allowing the anthraquinone raw material to react well; ② the addition of di(hydroxyalkyl)anthraquinone in component A, with the high reactivity of the hydroxyl groups, allows for sufficient and efficient reaction. Therefore, the two anthraquinone structures can react well, and the anthraquinone structure is more uniformly dispersed in the polyurethane, playing the following roles: ① promoting denitrification; ② improving the mechanical strength and durability of the polyurethane. Especially in the preparation of foamed polyurethane in this invention, the reactivity of water with NCO groups is very high. If the reactivity of the amino or hydroxyl groups on the anthraquinone is relatively low, the anthraquinone compound may not react completely, affecting the performance of the foamed polyurethane.

[0033] For example, the weight percentage of anthraquinone in polyisocyanate compounds can be any value or any value between 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, etc.

[0034] The polymeric diol can be a polyester diol, a polyether diol, etc., with a number-average molecular weight of 500-2000 g / mol. Since the foamed polyurethane of this invention needs to be immersed in nitrogen-containing wastewater for a long period, the polyurethane requires excellent hydrolysis resistance. Therefore, the polymeric diol can be a polyether diol, such as polytetrahydrofuran ether diol (PTMEG), polypropylene glycol (PPG), polyethylene glycol (PEG), PEG / PPG copolymer, etc. When the polyether contains PEG, the hydrophilicity of PEG can improve the surface energy and hydrophilicity of the foamed polyurethane, allowing the nitrogen-containing wastewater to better wet the surface of the foamed polyurethane, which is more conducive to the denitrification promoting effect of anthraquinone.

[0035] Chain extenders can be 1,2-ethylene glycol, 1,4-butanediol, 1,6-hexanediol, etc.

[0036] For example, the weight parts of di(hydroxyalkyl)anthraquinone can be any value or any value between 0.5 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, etc. Taking 1,4-bis[(hydroxyethyl)amino]anthraquinone as an example, its structure is shown in the following formula (1).

[0037] (1)

[0039] The hydroxyl group is separated from the anthraquinone structure by an ethylene structure and a secondary amino group. The anthraquinone structure has a lower steric hindrance effect on the hydroxyl group, resulting in higher activity of the hydroxyl group. However, the anthraquinone structure has a greater steric hindrance effect on the secondary amino group, resulting in lower activity of the secondary amino group.

[0040] In some embodiments, the NCO content of the polyisocyanate compound is not less than 10 wt%. If the NCO content of the polyisocyanate compound is low, its reactivity with component A will be low, which is detrimental to obtaining uniformly foamed polyurethane. For example, the NCO content of the polyisocyanate compound can be any value or any value between 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 16 wt%, 17 wt%, 18 wt%, 19 wt%, 20 wt%, etc.

[0041] In some embodiments, the polyisocyanate compound is obtained by reacting reactants comprising diaminoanthraquinone and diisocyanate monomers.

[0042] In some embodiments, diaminoanthraquinone is selected from one or a combination of two or more of 1,2-diaminoanthraquinone, 1,4-diaminoanthraquinone, 1,8-diaminoanthraquinone, 2,5-diaminoanthraquinone, and 2,6-diaminoanthraquinone. The diaminoanthraquinone molecule contains two primary amino groups, all of which can undergo condensation reactions with diisocyanate monomers to form prepolymers with NCO terminal groups.

[0043] In the preparation of polyurethane, polyisocyanate compounds typically contain diisocyanate monomers or adducts of diisocyanate monomers with other polymers. This invention utilizes the reaction between diaminoanthraquinone and diisocyanate monomers to chemically bond the anthraquinone structure to the polyisocyanate compound.

[0044] In some embodiments, the diisocyanate monomer is selected from one or a combination of two or more of hexamethylene diisocyanate (HDI), dicyclohexylmethane diisocyanate (HMDI), isophthalic dimethyl isocyanate (XDI), diphenylmethane diisocyanate (MDI), tetramethyl isophthalic diisocyanate (TMXDI), isophorone diisocyanate (IPDI), naphthalene diisocyanate (NDI), and toluene diisocyanate (TDI).

[0045] In some embodiments, the reaction raw materials further include polyether polyols;

[0046] The molar ratio of polyether polyol to diaminoanthraquinone is 0.5-3:1. For example, the molar ratio can be any value or any value between 0.5:1, 1:1, 1.5:1, 2:1, 2.5:1, 3:1, etc.

[0047] Introducing polyether polyols into polyisocyanate compounds can prevent the obtained polyurethane foam from having an excessively high crosslinking density, which would result in a rigid polyurethane foam. This results in polyurethane foam with better elasticity and impact resistance.

[0048] In some embodiments, the catalyst is selected from dihydroxyalkylamine;

[0049] The crosslinking agent is selected from triethanolamine or triisopropanolamine;

[0050] The carbon-based materials are selected from one or a combination of two or more of carbon nanotubes, graphene, and graphene oxide.

[0051] Dihydroxyalkylamines can be used as both catalysts and crosslinking agents.

[0052] Carbon-based materials have good electrical conductivity, which can improve the performance of anthraquinone as a redox mediator, accelerate denitrification efficiency, and enhance the denitrification promoting effect.

[0053] In some embodiments, the surface of the carbon-based material is chemically bonded with one or more of primary amines, secondary amines, and hydroxyl groups. These chemically bonded primary amines, secondary amines, and hydroxyl groups containing active hydrogen can participate in the reaction of polyurethane. The carbon-based material can also be chemically bonded into the polyurethane structure, improving its dispersibility and effectiveness within the polyurethane. For example, this results in better mechanical properties in the foamed polyurethane and a better promoting effect on denitrification. The chemical bonding of primary amines, secondary amines, and hydroxyl groups containing active hydrogen to the surface of the carbon-based material can be achieved through surface treatment with a silane coupling agent, such as KH-550, KH-560, or KH-792.

[0054] In some embodiments, the molar ratio of active hydrogen in component A to NCO groups in component B is 1:1.08-1.2. For example, the molar ratio can be any value or any value between 1:1.08, 1:1.1, 1:1.12, 1:1.15, 1:1.17, 1:1.2, etc.

[0055] On the other hand, the present invention also proposes an application of the composite foamed polyurethane material described in any of the above embodiments for the treatment of nitrogen-containing wastewater.

[0056] The composite foamed polyurethane material of this invention features high mechanical strength and good durability. Furthermore, its density can be adjusted by varying the degree of foaming to suit different nitrogen-containing wastewaters. It can remain suspended in nitrogen-containing wastewater and exert a long-term effect in promoting denitrification. The composite foamed polyurethane material of this invention can be prepared into foam fillers with different structures or shapes using different molds as needed.

[0057] The technical solution of the present invention will be further described and illustrated below with reference to various embodiments. Unless otherwise specified, the parts mentioned in the following embodiments are parts by weight. Example 1

[0058] Composite polyurethane foam material, composed of component A and component B;

[0059] The raw material components of component A include: 100 parts PTMEG (number average molecular weight 1000), 1.5 parts 1,4-bis[(hydroxyethyl)amino]anthraquinone, 5 parts 1,4-butanediol, 1.5 parts diethanolamine, 2 parts triethanolamine, 0.2 parts graphene and 1 part water;

[0060] Component B is a polyisocyanate compound.

[0061] The molar ratio of active hydrogen in component A to NCO groups in component B is 1:1.1.

[0062] The preparation method of the polyisocyanate compound is as follows: under nitrogen protection, 2,6-diaminoanthraquinone and HMDI are added to the reaction vessel at a weight ratio of 7:93, and the mixture is stirred at room temperature for 1 hour, heated to 50°C and stirred for 2 hours, and then heated to 90°C and stirred for 2 hours to obtain the polyisocyanate compound.

[0063] After mixing components A and B through a pipe, the mixture is injected into a mold and heated at 60°C for 6 minutes to foam and cure.

[0064] Comparative Example 1

[0065] The difference between this comparative example and Example 1 is that in Example 1, the polyisocyanate compound does not contain anthraquinone structures, i.e., the polyisocyanate compound is HMDI. The remaining steps remain unchanged.

[0066] Comparative Example 2

[0067] The difference between this comparative example and Comparative Example 1 is that in Comparative Example 1, the amount of 1,4-bis[(hydroxyethyl)amino]anthraquinone was adjusted from 1.5 parts to 3 parts. The remaining steps remained unchanged.

[0068] Comparative Example 3

[0069] The difference between this comparative example and Comparative Example 1 is that in Example 1, 1,4-bis[(hydroxyethyl)amino]anthraquinone was replaced with an equal weight of 2-methylanthraquinone. The remaining steps remained unchanged.

[0070] Comparative Example 4

[0071] The difference between this comparative example and Example 1 is that in Example 1, the raw material component A does not contain 1,4-bis[(hydroxyethyl)amino]anthraquinone. The remaining steps remain unchanged.

[0072] Comparative Example 5

[0073] The difference between this comparative example and Comparative Example 4 is that in Comparative Example 4, the weight ratio of 2,6-diaminoanthraquinone and HMDI was adjusted from 7:93 to 2:8. The remaining steps remained unchanged.

[0074] Comparative Example 6

[0075] The difference between this comparative example and Comparative Example 1 is that in Example 1, 1,4-bis[(hydroxyethyl)amino]anthraquinone was replaced with an equal weight of 2,6-diaminoanthraquinone. The remaining steps remained unchanged.

[0076] Example 2

[0077] The difference between this embodiment and Example 1 is that in Example 1, the amount of 1,4-bis[(hydroxyethyl)amino]anthraquinone was adjusted from 1.5 parts to 3 parts. The remaining steps remain unchanged.

[0078] Example 3

[0079] The difference between this embodiment and Example 1 is as follows: In Example 1, the preparation method of the polyisocyanate compound was adjusted as follows: 2,6-diaminoanthraquinone, PEG-400, and HMDI were added to a reaction vessel, stirred at room temperature for 1 hour, heated to 50°C and stirred for 2 hours, and then heated to 90°C and stirred for 2 hours to obtain the polyisocyanate compound. The molar ratio of 2,6-diaminoanthraquinone to PEG was 1:2, and the weight percentage of 2,6-diaminoanthraquinone in the polyisocyanate compound was 7%. The remaining steps remained unchanged.

[0080] Example 4

[0081] The difference between this embodiment and Example 3 is that in Example 3, the weight percentage of 2,6-diaminoanthraquinone in the polyisocyanate compound was adjusted from 7% to 15%. The remaining steps remained unchanged.

[0082] Example 5

[0083] The difference between this embodiment and Example 4 is that in Example 4, the amount of 1,4-bis[(hydroxyethyl)amino]anthraquinone was adjusted from 1.5 parts to 0.5 parts. The remaining steps remained unchanged.

[0084] Example 6

[0085] The difference between this embodiment and Embodiment 3 is that in Embodiment 3, PTMEG is replaced with an equal weight of PPG with a number average molecular weight of 1000. The remaining steps remain unchanged.

[0086] Example 7

[0087] Composite polyurethane foam material, composed of component A and component B;

[0088] The raw material components of component A include: 100 parts PTMEG (number average molecular weight 1200), 1 part 1,4-bis[(hydroxyethyl)amino]anthraquinone, 3 parts 1,4-butanediol, 2 parts diethanolamine, 1 part triethanolamine, 0.15 parts graphene oxide and 1.5 parts water;

[0089] Component B is a polyisocyanate compound.

[0090] The molar ratio of active hydrogen in component A to NCO groups in component B is 1:1.16.

[0091] The preparation method of the polyisocyanate compound is as follows: under nitrogen protection, 1,5-diaminoanthraquinone and HDI are added to the reaction vessel at a weight ratio of 1:9, the mixture is stirred at room temperature for 1 h, heated to 50 °C and stirred for 2 h, and then heated to 90 °C and stirred for 2 h to obtain the polyisocyanate compound.

[0092] After mixing components A and B through a pipe, the mixture is injected into a mold and heated at 60°C for 6 minutes to foam and cure.

[0093] Example 8

[0094] The difference between this embodiment and Example 7 is as follows: In Example 7, the preparation method of the polyisocyanate compound was adjusted as follows: 2,5-diaminoanthraquinone, PPG-800, and HDI were added to a reaction vessel, stirred at room temperature for 1 hour, heated to 50°C and stirred for 2 hours, and then heated to 90°C and stirred for 2 hours to obtain the polyisocyanate compound. The molar ratio of 1,5-diaminoanthraquinone to PPG was 1:1, and the weight percentage of 1,5-diaminoanthraquinone in the polyisocyanate compound was 10%. The remaining steps remained unchanged.

[0095] Example 9

[0096] The difference between this embodiment and Example 8 is that in Example 8, the molar ratio of 1,5-diaminoanthraquinone and PPG was adjusted from 1:3 to 1:0.5. The remaining steps remain unchanged.

[0097] Example 10

[0098] The difference between this embodiment and Embodiment 7 is that in Embodiment 7, graphene oxide was replaced with an equal weight of graphene oxide bonded to primary amine groups. The remaining steps remain unchanged.

[0099] The graphene oxide bonded with primary amines was obtained by surface treatment of graphene oxide with KH-550. The specific operation is as follows: 1 part of graphene oxide was added to 1000 parts of anhydrous ethanol and ultrasonically dispersed for 20 min. 3 parts of KH-550 were added and the mixture was stirred and reacted at room temperature for 2 h. The temperature was raised to micro-reflux and the mixture was stirred and reacted for another 2 h. The mixture was then cooled, and the solid was collected by centrifugation. The solid was washed twice with anhydrous ethanol and dried overnight at 60 °C to obtain the final product.

[0100] Example 11

[0101] The difference between this embodiment and Example 10 is that in Example 10, the graphene oxide bonded to primary amines was replaced with an equal weight of graphene oxide bonded to secondary amines, and KH-550 was replaced with an equal weight of N-methyl-3-propyltrimethoxysilane. The remaining steps remained unchanged.

[0102] Performance testing

[0103] Tensile strength: Tested according to the method of GB / T 6344-2008.

[0104] Rebound rate: Tested according to the method of GB / T 6670-2008.

[0105] Hydrolysis resistance: The polyurethane foam to be tested was placed in water at 90℃ for 48 hours, then removed and placed at room temperature for 48 hours. The tensile strength was tested again, and the tensile strength retention rate A was calculated. A = tensile strength after test / tensile strength before test × 100%. The higher the tensile strength retention rate, the better the hydrolysis resistance.

[0106] Moist heat resistance: The polyurethane foam to be tested was placed in an environment of 80℃ and 80% humidity for 72 hours, and the tensile strength was tested again. The tensile strength retention rate B was calculated as B = tensile strength after test / tensile strength before test × 100%. The higher the tensile strength retention rate, the better the moisture heat resistance.

[0107] The results are shown in Table 1 below.

[0108] Table 1 Mechanical Performance Test Results

[0109]

[0110] Therefore, based on the results in Table 1 above, it can be seen that the foamed polyurethane of the present invention has good mechanical properties and elasticity, as well as good durability and stability. It maintains good mechanical strength even after hydrolysis and damp heat resistance tests. Comparing the results of Example 1 and Comparative Examples 1-5, it can be seen that the anthraquinone structure is distributed in components A and B and can be chemically bonded to the polyurethane, resulting in good mechanical properties and high stability of the foamed polyurethane. Comparing Examples 1 and 4, and Examples 7-9, the introduction of polyether segments into the isocyanate composition of component B can significantly improve the elasticity of the foamed polyurethane. Comparing Examples 7, 10, and 11, the chemical bonds and primary or secondary amine groups on the graphene oxide surface can improve the mechanical strength and resilience of the foamed polyurethane, and also provide better hydrolysis and damp heat resistance.

[0111] Nitrogen removal performance test: Prepare 500 ml of denitrification medium with an initial concentration of 50 mg / L (initial nitrate concentration of 50 mg / L), inoculate with 3% microorganisms activated and cultured in LB medium, and place the inoculated denitrification medium in a constant temperature shaker set at 36℃ and 120 r / min to ensure that 10 g of the test packing material in the medium is in a good fluidized state. Samples are taken every 5 h. After centrifuging at 3000 rpm for 10 min, the supernatant of the sample is quantitatively diluted, and the absorbance is measured using a UV spectrophotometer to calculate the corresponding concentration and the nitrogen removal rate. The nitrogen removal rate at time t = (C0 - C...) / (C0 - C ... t ) / C0×100%, where C0 is the initial concentration of nitrate, C t Let t represent the nitrate concentration at time t. Each sample was measured three times, and the average of the three results was taken. The results are shown in Table 2 below.

[0112] Table 2 Denitrification rate / %

[0113]

[0114] Therefore, the composite foamed polyurethane of the present invention has a good denitrification effect on nitrogen-containing wastewater, with a fast denitrification rate and high denitrification efficiency.

[0115] As described above, the basic principles, main features, and advantages of the present invention have been shown and described. Those skilled in the art should understand that the present invention is not limited to the above embodiments, which are merely preferred embodiments and should not be construed as limiting the scope of the invention. All equivalent changes and modifications made in accordance with the scope of the patent and the description should still fall within the scope of the present invention. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A composite foamed polyurethane material, characterized in that, It consists of component A and component B; The raw material components of component A include: 100 parts polymer diol, 0.5-3 parts di(hydroxyalkyl)anthraquinone, 1-8 parts chain extender, 1-3 parts catalyst, 0-5 parts crosslinking agent, 0.1-2 parts carbon-based material, and 0.5-2 parts water; The di(hydroxyalkyl)anthraquinone is selected from one or a combination of two or more of 1,4-bis[(hydroxyethyl)amino]anthraquinone, 1-[(2-hydroxyethyl)amino]-4-[(3-hydroxypropyl)amino]anthraquinone, 1,4-bis[(hydroxypropyl)amino]anthraquinone, 2,5-bis[(hydroxypropyl)amino]anthraquinone, 1,8-bis[(hydroxypropyl)amino]anthraquinone, 2,5-bis[(hydroxyethyl)amino]anthraquinone, 2,6-bis[(hydroxyethyl)amino]anthraquinone and 2,6-bis[(hydroxypropyl)amino]anthraquinone; Component B is a polyisocyanate compound; The polyisocyanate compound contains 5-15% anthraquinone by weight chemical bonding; The polyisocyanate compound is obtained by reacting reactants containing diaminoanthraquinone and diisocyanate monomers.

2. The composite foamed polyurethane material according to claim 1, characterized in that, The NCO content of the polyisocyanate compound is not less than 10 wt%.

3. The composite foamed polyurethane material according to claim 1, characterized in that, The diaminoanthraquinone is selected from one or a combination of two or more of 1,2-diaminoanthraquinone, 1,4-diaminoanthraquinone, 1,8-diaminoanthraquinone, 2,5-diaminoanthraquinone, and 2,6-diaminoanthraquinone.

4. The composite foamed polyurethane material according to claim 1, characterized in that, The diisocyanate monomer is selected from one or a combination of two or more of HDI, HMDI, XDI, MDI, TMXDI, IPDI, NDI and TDI.

5. The composite foamed polyurethane material according to claim 1, characterized in that, The reaction raw materials also include polyether polyols; The molar ratio of the polyether polyol to the diaminoanthraquinone is 0.5-3:

1.

6. The composite foamed polyurethane material according to claim 1, characterized in that, The catalyst is selected from dihydroxyalkylamine; The crosslinking agent is selected from triethanolamine or triisopropanolamine; The carbon-based material is selected from one or a combination of two or more of carbon nanotubes, graphene, and graphene oxide.

7. The composite foamed polyurethane material according to claim 6, characterized in that, The carbon-based material surface is chemically bonded with one or more of primary amino groups, secondary amino groups, and hydroxyl groups.

8. The composite foamed polyurethane material according to claim 1, characterized in that, The molar ratio of active hydrogen in component A to NCO groups in component B is 1:1.08-1.

2.

9. An application of the composite foamed polyurethane material according to any one of claims 1-8, characterized in that, It is used for the treatment of nitrogen-containing wastewater.

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