CN104437394B - Dual-layer high-amino density plant fiber-based adsorption material and preparation method and application thereof - Google Patents

Abstract

The invention discloses a double-layer high amino density plant fiber-based adsorption material as well as a preparation method and application thereof. The double-layer high amino density plant fiber-based adsorption material is based on plant fiber, specifically bagasse, bamboo shoot powder, corncob powder, sisal hemp, straw or cotton fiber, etc., after alkali pretreatment, grafting reaction, amination Reaction, addition reaction, PEI amide substitution reaction to prepare. The fiber-based adsorption material of the present invention has high thermal stability and chemical stability. The adsorption material has high adsorption capacity and good adsorption and capture performance for acid gas, and can be used in the field of adsorption and capture of _CO2 in flue gas. At the same time, the material also has good antibacterial properties and can be applied in the field of wood-plastic materials to prevent mildew of wood fibers, and has good application prospects in other antibacterial fields. Moreover, after the adsorption material absorbs gas, it can be regenerated by thermal desorption, which is a recyclable and regenerated adsorption material.

Description

A double-layer high amino density plant fiber-based adsorption material and its preparation method and application

technical field

The invention belongs to the technical field of adsorption materials. More specifically, it relates to a double-layer high amino density plant fiber-based adsorption material and its preparation method and application.

Background technique

The greenhouse effect has become one of the most serious environmental problems faced by human beings. As the main component of greenhouse gases, the content of CO ₂ in the atmosphere is getting higher and higher, which also makes the reduction of CO ₂ emissions become the focus of research in this field. CO ₂ capture and storage technology (CCS) has become an international hot topic of research. As one of the solid-state adsorbents for separating and enriching _CO2 , solid-state amine adsorbent has high selectivity for _CO2 and is not easily disturbed by water or other gases, and can be used for CO2 in a relatively wide temperature range and pressure range ₂ enrichment. The solid amine fiber based on fiber has the advantages of high adsorption capacity, excellent recycling performance, and wide source of raw materials, and has broad application prospects in the field of gas separation.

For the modified solid amine adsorbents, the adsorbents have different basicity, and the adsorption capacity and amino group utilization rate decrease with the decrease of basicity. It can be seen that the alkalinity of the material plays a decisive role in its adsorption performance: on the one hand, the increase of alkalinity is beneficial to the improvement of the adsorption capacity of the material; on the other hand, the lower the alkalinity of the material, the faster the desorption rate. That is to say, under the same adsorption conditions, solid amine adsorption materials containing primary amines have a faster adsorption rate and higher adsorption capacity for _CO2 , but desorption becomes more difficult than secondary and tertiary amines. Therefore, the adsorption capacity of the material can be improved by loading multiple functional amine-based reagents on the substrate at the same time. Among them, the solid-state amine adsorption material loaded with high-molecular-weight amine-based compounds such as PEI has a high amino density and can effectively improve the adsorption performance of the material. Its adsorption performance may be affected by the average size, branching degree, etc. of PEI molecular chains. This is mainly due to the fact that the longer the polymer molecular chain is, the easier it is to form clusters during the preparation process, and the more difficult it is to disperse into the matrix; the greater the degree of branching, the greater the diffusion and mass transfer resistance of _CO2 on the adsorption material. Therefore, under the same substrate and the same loading capacity, the adsorption capacity and amino group efficiency of the adsorbents loaded with PEI may not be as good as those loaded with TEPA. How to ensure high amino density without reducing amino efficiency and adsorption capacity becomes particularly important.

On the other hand, my country is a large agricultural country, and there is a large amount of agricultural waste that needs to be processed and recycled every year. These agricultural wastes contain a large amount of cellulose fibers. Compared with other synthetic fibers, these natural cellulose fibers have the characteristics of wide sources, low price, low density, and degradable recycling. Not only that, these cellulose fibers are expected to be used in various fields of adsorption materials due to their rough surface and heterogeneity of physical and chemical structures. In recent years, a large number of studies have applied it to the fields of printing and dyeing industry, heavy metal ion adsorption, and industrial wastewater treatment. At present, there are no studies and reports on the application of these plant fibers to the adsorption of greenhouse gases.

Contents of the invention

The technical problem to be solved in the present invention is to overcome the deficiencies of the existing gas adsorption technologies such as _CO2 , and provide a double-layer high amino density plant fiber-based adsorption material prepared with plant fibers as a matrix, so as to realize the full and efficient absorption of agricultural waste. Reasonable utilization can reduce the shortcomings of high cost and few sources of raw materials in the field of adsorbents, and increase the density of amino groups through steps such as grafting and amination on a limited substrate, effectively improving the adsorption performance of materials for acid gases such as CO ₂ , and realizing Efficient application of this kind of double-layer high amino density plant fiber-based adsorption material in the field of adsorption.

Another object of the present invention is to provide a method for preparing the above-mentioned double-layer high amino density plant fiber-based adsorption material.

Another object of the present invention is to provide the application of the above-mentioned double-layer high amino density plant fiber-based adsorption material.

The above object of the present invention is achieved through the following technical solutions:

The invention provides a double-layer high amino density plant fiber-based adsorption material, which is prepared by taking the plant fiber as a matrix and sequentially undergoing alkali pretreatment, grafting reaction, amination reaction, addition reaction and PEI amide substitution reaction. The thermal decomposition temperature of the adsorption material is above 300°C, and it has excellent acid gas adsorption and capture performance and excellent antibacterial performance; And/or the resolution rate of sulfur dioxide can still reach more than 90%, and the regeneration efficiency is more than 93%.

Wherein, preferably, the plant fiber is bagasse, bamboo shoot powder, corncob powder, sisal hemp, straw or cotton fiber. There are a large number of hydroxyl reactive groups on the surface of plant fibers, which can be further functionalized.

The present invention also adopts a method for preparing the above-mentioned double-layer high amino density plant fiber-based adsorption material, the steps are as follows:

S1. Alkali pretreatment: place the plant fibers in NaOH aqueous solution for ultrasonic vibration treatment, and dry;

S2. Grafting reaction: mix the plant fiber after the alkali pretreatment with the unsaturated grafting monomer solution, then add the initiator H ₂ O ₂ and ferrous amine sulfate solution, and carry out the grafting reaction to obtain the grafted fiber;

S3. Amination reaction: adding polyamine to the grafted fibers for amination reaction to obtain a single-layer amino plant fiber-based material;

S4. Addition reaction: Mix the single-layer amino plant fiber-based material with the unsaturated graft monomer solution, and perform an addition reaction (Michael addition reaction) after ultrasonic treatment to obtain the added single-layer amino plant fiber base Material;

S5. PEI amide substitution reaction: Mix the added single-layer amino plant fiber-based material with polyethyleneimine (PEI) for amide substitution reaction to obtain a double-layer high amino density plant fiber-based adsorption material.

Preferably, the alkali pretreatment described in step S1 is specifically:

S11. placing the plant fiber in 10-20wt% NaOH aqueous solution, and treating it with 100-400W ultrasonic vibration for 1-2 hours;

S12. After ultrasonic treatment, soak at 50°C for 10-24 hours;

S13. Pour off the solution, wash the obtained fiber several times with water until neutral, and dry at 60°C.

The plant fiber is bagasse, bamboo shoot powder, corn cob powder, sisal hemp, straw or cotton fiber.

Preferably, the grafting reaction described in step S2 is specifically:

S21. According to the ratio of the weight of the plant fiber after the alkali pretreatment to the volume of the unsaturated graft monomer solution is 1:10～1:50, the two are mixed; the concentration of the unsaturated graft monomer solution is 2～20wt%;

S22. According to the volume ratio of H ₂ O ₂ to the unsaturated graft monomer solution is 0.2:100 to 2:100, add initiator H ₂ O ₂ to the solution mixed in S21;

S23. According to the volume ratio of ferrous amine sulfate solution and unsaturated graft monomer solution is 1:5, add ferrous amine sulfate solution in the solution after S22 treatment; The concentration of described ferrous amine sulfate is 1×10 ^-3 ～1×10 ^-1 g/mL;

S24. After reacting for 1 to 24 hours at 30 to 80°C, soak and filter with ethanol for 2 to 5 times, then wash and filter with water for 2 to 5 times to remove the homopolymer, and dry in vacuum at 60°C to obtain the stick fibers.

Preferably, the amination reaction described in step S3 is specifically:

S31. According to the weight ratio of polyamine to graft fiber is 2:1～100:1, add polyamine to graft fiber;

S32. React at 100-150°C for 6-10 hours, soak with water for several times (2-5 times), finally rinse with ethanol, filter with suction, and dry at 60°C to obtain a single-layer amino plant fiber-based material.

Preferably, the addition reaction described in step S4 is specifically:

S41. According to the ratio of the weight of the single-layer amino plant fiber-based material to the volume of the unsaturated graft monomer solution is 1:10～1:60, the two are mixed, and the concentration of the unsaturated graft monomer solution is 5～50wt%;

S42. After treating for 1-2 hours under 100-400W ultrasonic conditions, continue to react in a 10-60°C water bath for 1-24 hours, so that the fibers undergo Michael addition reaction (Michael addition reaction);

S43. Soak and wash with water for several times (2-5 times), finally rinse with ethanol, filter with suction, and dry at 60°C to obtain a single-layer amino plant fiber-based material after addition.

Preferably, the PEI amide substitution reaction described in step S5 is specifically:

S51. According to the ratio of the weight of the added single-layer amino plant fiber-based material to the volume of polyethyleneimine (PEI) is 1:5 to 1:60, mix the two, and the concentration of polyethyleneimine 5~15wt%;

S52. Reacting at 20-60° C. for 10-48 hours, so that the fiber and polyethyleneimine undergo an amide substitution reaction;

S53. Wash with ethanol to remove excess polyethyleneimine, filter with suction, and dry at 60°C to obtain a double-layer high amino density plant fiber-based adsorption material.

In addition, preferably, the above-mentioned unsaturated grafting monomer solution is: acrylamide solution, methyl acrylate solution, acrylonitrile solution, acrylic acid solution or glycidyl methacrylate solution.

The aforementioned polyamines are ethylenediamine, diethylamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine or pentaethylenehexamine.

The present invention also provides the application of the above-mentioned double-layer high amino density plant fiber-based adsorption material in the adsorption of _acid gas, especially in the adsorption of _CO2 and/or SO2.

In addition, the present invention also provides the application of the above-mentioned double-layer high amino density plant fiber-based adsorption material in the aspects of antibacterial wood-plastic materials or preventing mildew of wood fibers. Preferably it is applied against Staphylococcus aureus, Escherichia coli or Candida albicans.

The present invention is the first attempt to use natural and renewable plant fibers in the field of _CO2 adsorption and enrichment to prepare plant fiber-based adsorption materials _; In order to optimize and innovate, firstly, the plant fiber is used as the substrate, followed by alkali pretreatment, grafting reaction, and amination reaction to obtain a single-layer amino plant fiber-based material; then the addition reaction and PEI amide substitution reaction are introduced to obtain a , methyl acrylate, acrylonitrile, acrylic acid or glycidyl methacrylate and other unsaturated grafting monomer solutions for Michael addition reaction, and then amide substitution reaction with PEI, and finally a double-layer high amino density plant fiber base Adsorption material: The adsorption material not only has excellent adsorption and capture performance for acid gas, but also has excellent antibacterial performance, and is a recyclable and environmentally friendly adsorption material with broad application prospects.

The present invention has the following beneficial effects:

The invention discloses a double-layer high amino density plant fiber-based adsorption material as well as a preparation method and application thereof. The double-layer high amino density plant fiber-based adsorption material is prepared by taking plant fiber as a matrix and undergoing alkali pretreatment, grafting reaction, amination reaction, addition reaction and PEI amide substitution reaction. The plant fibers used are natural and renewable bagasse, bamboo shoot powder, corncob powder, sisal hemp, straw or cotton fiber, etc., which are green and environmentally friendly, and reduce the cost of raw materials without causing secondary pollution to the global atmosphere. Under the circumstances, it provides a certain technical support for the separation and enrichment of CO ₂ , and it is of great significance to apply these plant fibers to the adsorption of greenhouse gases.

At the same time, the present invention appropriately increases the branched structure similar to PEI, and the prepared double-layered plant fiber-based adsorption material with high amino density can increase the adsorption capacity and amino efficiency while increasing the amino density. The adsorption material has good adsorption capacity and good adsorption and capture performance for acid gases, and can be used in the field of adsorption and capture of CO ₂ in flue gas. The adsorption capacity for CO ₂ is above 2.0mmol CO ₂ /g; for SO ₂ The adsorption capacity is above 100mg/g.

In addition, the plant fiber-based adsorption material of the present invention not only has good adsorption performance, but also has good antibacterial performance. The antibacterial rate against Staphylococcus aureus is above 98.3%, and the antibacterial rate against Escherichia coli is above 96.4%. The antibacterial rate of Candida is above 95.6%. It can be applied to the field of wood-plastic materials, and has important application prospects for preventing mildew of wood fibers and improving the quality of wood-plastic materials. It also has good application prospects in other antibacterial fields.

The thermal decomposition temperature of the fiber-based adsorption material of the present invention is above 300° C., and has high thermal stability and chemical stability. Moreover, the adsorption material can be regenerated by thermal desorption after adsorbing gas. After 10 regenerations, the resolution rate of carbon dioxide and sulfur dioxide can still reach more than 90%, the regeneration efficiency is more than 93%, and the regeneration performance is good. It is a recyclable Recycled environmentally friendly absorbent material.

Description of drawings

Figure 1 is the thermal weight loss of bagasse-based double-layer high amino density fiber-based adsorbent material under nitrogen.

detailed description

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but the embodiments do not limit the present invention in any form. Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the technical field.

Unless otherwise specified, the reagents and materials used in the present invention are commercially available.

Example 1

1. Using bagasse fiber as the matrix to prepare the adsorption material, the steps are as follows:

(1) Alkali pretreatment: After pulverizing the bagasse fiber, immerse it in 20wt% NaOH aqueous solution, put it into an ultrasonic shock reactor, and treat it under the condition of ultrasonic power 100W for 1.5h. After the ultrasonic treatment, take out the Soak under temperature conditions for 24 hours, pour off the solution, wash the obtained fiber with water for several times until neutral, and vacuum dry in an oven at 60°C until constant weight.

(2) Grafting reaction: Mix the bagasse fiber obtained in step (1) with 10wt% acrylamide, and control the ratio of the weight of the bagasse fiber to the volume of acrylamide to be 1:50. After mixing evenly, add 30v/v % H ₂ O ₂ and 2×10 ^-2 g/mL ferrous amine sulfate solution; the volume ratio of the required volume of H ₂ O ₂ to acrylamide is 0.8:100, the required volume of ferrous amine sulfate solution to the volume ratio of acrylamide The volume ratio is 1:5; after reflux reaction at 60°C for 4 hours, soak and filter with ethanol for 3 times, then with water for 3 times, dry in a vacuum oven at 60°C until constant weight, and obtain bagasse-based stick fibers.

(3) Amination reaction: Add triethylenetetramine to the bagasse-based grafted fiber obtained in step (2), and the ratio of the weight of the grafted fiber to the volume of triethylenetetramine is 1:100. The mixture was reacted at 130°C for 8h. After the reaction, soak and wash with water several times, and finally rinse with ethanol, filter with suction, and dry in an oven at 60°C. A bagasse-based single-layer amino fiber material is obtained.

(4) Addition reaction: Mix the bagasse-based single-layer amino fiber material obtained in step (3) with a 5wt% acrylamide solution, and control the ratio of the weight of the bagasse-based single-layer amino fiber material to the volume of the acrylamide solution to be 1:60, put it into an ultrasonic shock reactor, treat it under the condition of ultrasonic power 400W for 2 hours, take it out after the ultrasonic treatment, and continue the reaction in a water bath for 1 hour, and the reaction temperature is 60°C, so that the fibers will undergo Michael addition. After the reaction, the mixture was rinsed with water for several times, finally rinsed with ethanol, filtered with suction, and dried in an oven at 60°C to obtain a bagasse-based single-layer amino fiber material after addition.

(5) PEI amide substitution reaction: mix the added bagasse-based single-layer amino fiber material obtained in step (4) with polyacetamide (PEI), and control the weight of the added bagasse-based single-layer amino fiber material The ratio of PEI to volume is 1:40, the concentration of PEI is 7wt%, the reaction time is 12h, and the reaction temperature is 60°C, so that the fiber and the polyamine reagent PEI undergo amide substitution reaction. After the reaction, wash with ethanol to remove excess polyamide The amine reagent was suction filtered and dried in an oven at 60°C to obtain a bagasse-based double-layer high amino density fiber-based adsorption material.

2. After testing, the thermal weight loss of the bagasse-based double-layer high amino density fiber-based adsorption material under nitrogen is shown in Figure 1. It can be seen from Figure 1 that the bagasse-based double-layer high amino density fiber has a slight weight loss before 100°C, which is mainly due to the physical adsorption of water, _CO2 , etc. on the fiber surface, after 100°C the bagasse-based double-layer high The weight of the amino density fiber remains stable until about 230°C, the bagasse-based double-layer high amino density fiber appears obvious weight loss. It can be considered that the amination and grafting products of bagasse-based double-layer high-amino-density fibers begin to degrade, and the fiber matrix begins to degrade at about 350°C, overlapping with the weight-loss section of the former. The obtained bagasse-based double-layer high amino density fiber-based adsorption material can basically maintain thermal stability at about 200°C. In other words, when the adsorption material is used at 200°C, no degradation of the adsorption material will occur. It can be used for adsorption, separation and enrichment of _CO2 in conventional flue gas.

3. After measurement, the above-mentioned bagasse-based double-layer high amino density fiber-based adsorption material has an adsorption capacity of 7.42 mmol CO ₂ /g for CO ₂ and an adsorption capacity of 103 mg SO ₂ /g for SO ₂ .

After 10 cycles of regeneration, the resolution rate of carbon dioxide and sulfur dioxide is 90%, and the regeneration efficiency is 93%.

The antibacterial rate of bagasse-based double-layer high amino density fiber-based adsorbent material against Staphylococcus aureus was 98.3%, the antibacterial rate against Escherichia coli was 96.4%, and the antibacterial rate against Candida albicans was 95.6%.

Example 2

1. Using straw fiber as the matrix to prepare the adsorption material, the steps are as follows:

(1) Alkali pretreatment: crush the straw fibers, immerse them in 10wt% NaOH aqueous solution, put them into an ultrasonic shock reactor, and treat them for 1 hour under the condition of ultrasonic power 400W. After the ultrasonic treatment, take them out at a temperature of 50°C Soak under water for 10 hours, pour off the solution, wash the obtained fiber with water for several times until neutral, and dry it in a vacuum oven at 60°C until it reaches a constant weight.

(2) Grafting reaction: mix the straw fibers obtained in step (1) with 2wt% methyl methacrylate, control the ratio of the weight of straw fibers to the volume of methyl methacrylate to be 1:10, and mix well, Add 30v/v% H ₂ O ₂ and 1×10 ^-3 g/mL ferrous amine sulfate solution; the volume ratio of the required volume of H ₂ O ₂ to methyl methacrylate is 0.2:100, and ferrous amine sulfate The volume ratio of the required volume of the solution to methyl methacrylate is 1:5; after reflux reaction at 30°C for 24 hours, soak and filter with ethanol for 4 times, then wash with water for 4 times, vacuum in an oven at 60°C Dry to constant weight to obtain straw-based grafted fibers.

(3) Amination reaction: Add diethylenetriamine to the straw-based graft fibers obtained in step (2), and the ratio of the weight of the graft fibers to the volume of diethylenetriamine is 1:10. The mixture was reacted at 100 °C for 10 h. After the reaction, soak and wash with water several times, and finally rinse with ethanol, filter with suction, and dry in an oven at 60°C. A straw-based single-layer amino fiber material is obtained.

(4) Addition reaction: Mix the straw-based single-layer amino fiber material obtained in step (3) with 50wt% acrylamide solution, and control the ratio of the weight of the straw-based single-layer amino fiber material to the volume of the acrylamide solution to be 1: 10. Put it into an ultrasonic shock reactor, treat it under the condition of ultrasonic power 100W for 1h, take it out after the ultrasonic treatment, and continue the reaction in the water bath. The reaction time is 24h, and the reaction temperature is 10°C, so that Michael addition reaction occurs on the fiber , after the reaction is completed, soak and wash with water for several times, finally wash with ethanol, filter with suction, and dry in an oven at 60°C to obtain the added straw-based single-layer amino fiber material.

(5) PEI amide substitution reaction: mix the added straw-based single-layer amino fiber material obtained in step (4) with PEI, and control the ratio of the weight of the added straw-based single-layer amino fiber material to the volume of PEI to be 1: 5. The concentration of PEI is 5 wt%, the reaction time is 10h, and the reaction temperature is 60°C, so that the fiber and polyamine reagent PEI undergo amide substitution reaction. After the reaction, wash with ethanol to remove excess polyamine reagent and suction filter, and place in Dry in an oven at 60°C to obtain a straw-based double-layer high amino density fiber-based adsorption material.

2. It has been determined that the CO ₂ adsorption capacity of the straw-based double-layer high amino density fiber-based adsorption material is 2.0 mmol CO ₂ /g. The adsorption capacity for SO ₂ is 100 mg SO ₂ /g.

After 10 cycles of regeneration, the resolution rate of carbon dioxide and sulfur dioxide is 93%, and the regeneration efficiency is 95%.

The antibacterial rate of the straw-based double-layer high amino density fiber-based absorbent material was 98.7% against Staphylococcus aureus, 96.9% against Escherichia coli, and 95.7% against Candida albicans.

Example 3

1. Using sisal fibrils as the substrate to prepare the adsorption material, the steps are as follows:

(1) Alkali pretreatment: Cut sisal fibrils into small pieces of about 2-4cm, immerse them in 20wt% NaOH aqueous solution, put them in an ultrasonic shock reactor, and treat them for 2 hours under the condition of ultrasonic power 300W. , take it out and soak it for 20 hours at a temperature of 50°C, pour off the solution, wash the obtained fiber with water several times until it becomes neutral, and dry it in a vacuum oven at 60°C until it reaches a constant weight.

(2) Grafting reaction: Mix the sisal fibrils obtained in step (1) with 20wt% methyl acrylate, and control the ratio of the weight of the sisal fibrils to the volume of methyl acrylate to be 1:50. After mixing evenly, add 30 % H ₂ O ₂ and 1×10 ^-1 g/mL ferrous amine sulfate solution; the volume ratio of H ₂ O ₂ required volume to methyl acrylate is 2:100, the required volume of ferrous amine sulfate solution to methyl acrylate The volume ratio of the ester is 1:5; after reflux reaction at 80°C for 1 hour, soak and filter with ethanol for 5 times, then soak with water for 5 times, dry in a 60°C oven under vacuum until constant weight, and obtain sisal base graft fiber.

(3) Amination reaction: Add ethylenediamine to the sisal-based grafted fiber obtained in step (2), and the ratio of the weight of the grafted fiber to the volume of ethylenediamine is 1:2. The mixture was reacted at 150°C for 6h. After the reaction, soak and wash with water several times, and finally rinse with ethanol, filter with suction, and dry in an oven at 60°C. A sisal-based single-layer amino fiber material was obtained.

(4) Addition reaction: Mix the sisal-based single-layer amino fiber material obtained in step (3) with a 15%wt methyl methacrylate solution to control the weight of the sisal-based single-layer amino fiber material and methacrylic acid The ratio of the volume of the methyl ester solution is 1:100, put it into an ultrasonic vibration reactor, process it under the condition of ultrasonic power 300W for 2h, take it out after the ultrasonic treatment ends, and continue to react in a water bath, the reaction time is 24h, and the reaction temperature is At 70°C, the fiber undergoes Michael addition reaction. After the reaction, the fiber is soaked several times with water, finally rinsed with ethanol, filtered with suction, and dried in an oven at 60°C to obtain a sisal-based single-layer amino fiber material after addition.

(5) PEI amide substitution reaction: mix the added sisal-based single-layer amino fiber material obtained in step (4) with PEI, and control the weight ratio of the added sisal-based single-layer amino fiber material to the PEI volume ratio as follows: 1:60, the concentration of PEI is 15wt%, the reaction time is 48h, and the reaction temperature is 20°C, so that the fiber and PEI undergo an amide substitution reaction. After the reaction, wash with ethanol to remove excess polyamine reagent and suction filter, and place at 60°C drying in an oven to obtain a sisal-based double-layer high amino density fiber-based adsorption material.

2. After measurement, the adsorption capacity of the above-mentioned sisal-based double-layer high amino density fiber-based adsorption material for CO ₂ is 3.22 mmol CO ₂ /g, and the adsorption capacity for SO ₂ is 106 mg SO ₂ /g.

After 10 cycles of regeneration, the resolution rate of carbon dioxide and sulfur dioxide is 95%, and the regeneration efficiency is 98%.

The antibacterial rate of the sisal-based double-layer high amino density fiber-based absorbent material against Staphylococcus aureus was 98.6%, the antibacterial rate against Escherichia coli was 96.5%, and the antibacterial rate against Candida albicans was 96.0%.

Example 4

1. Use cotton fiber as the matrix to prepare the adsorption material. The steps are as follows:

(1) Alkali pretreatment: Cut the cotton fibers into pieces, immerse them in 20wt% NaOH aqueous solution, put them into an ultrasonic shock reactor, and treat them for 1.5h under the condition of ultrasonic power of 300W. After the ultrasonic treatment, take out the Soak for 24 hours under temperature conditions, pour off the solution, wash the obtained fiber with water for several times until it becomes neutral, and dry it in a vacuum oven at 60°C until it reaches constant weight.

(2) Grafting reaction: mix the cotton fiber obtained in step (1) with 10wt% acrylic acid, control the ratio of the weight of cotton fiber to the volume of acrylic acid to be 1:40, after mixing evenly, add 30% H ₂ O ₂ and 5×10 ^-3 g/mL ferrous amine sulfate solution; the volume ratio of the required volume of H ₂ O ₂ to acrylic acid is 1:100, and the volume ratio of the required volume of ferrous amine sulfate solution to acrylic acid is 1:5; After reflux reaction at 70°C for 15 hours, soak and filter with ethanol for 3 times, then with water for 3 times, dry in a 60°C oven in vacuum until constant weight to obtain cotton fiber-based grafted fiber.

(3) Amination reaction: Add pentaethylene hexamine to the cotton fiber-based graft fiber obtained in step (2), and the ratio of the weight of the graft fiber to the volume of pentaethylene hexamine is 1:40. The mixture was reacted at 120°C for 8h. After the reaction, soak and wash with water several times, and finally rinse with ethanol, filter with suction, and dry in an oven at 60°C. A cotton fiber-based single-layer amino fiber material is obtained.

(4) Addition reaction: the cotton fiber-based single-layer amino fiber material obtained in step (3) is mixed with 15wt% acrylic acid solution, and the ratio of the weight of the cotton fiber-based single-layer amino fiber material to the volume of the acrylic acid solution is 1: 50, put it into an ultrasonic shock reactor, treat it under the condition of ultrasonic power 400W for 1h, take it out after the ultrasonic treatment, and continue the reaction in the water bath, the reaction time is 15h, and the reaction temperature is 50°C, so that Michael addition reaction occurs on the fiber , After the reaction is completed, soak and wash with water for several times, and finally wash with ethanol, filter with suction, and dry in an oven at 60°C to obtain a cotton fiber-based single-layer amino fiber material after addition.

(5) PEI amide substitution reaction: mix the added cotton fiber-based single-layer amino fiber material obtained in step (4) with PEI, and control the weight ratio of the added cotton fiber-based single-layer amino fiber material to PEI volume ratio as 1:40, the concentration of PEI is 10wt%, the reaction time is 15h, and the reaction temperature is 60°C, so that the fiber and the polyamine reagent PEI undergo amide substitution reaction. Dry in an oven at 60°C to obtain a cotton fiber-based double-layer high amino density fiber-based absorbent material.

2. After measurement, the above-mentioned cotton fiber-based double-layer high amino density fiber-based adsorption material has an adsorption capacity of 6.11 mmol CO ₂ /g for CO ₂ and an adsorption capacity of 100 mg SO ₂ /g for SO ₂ .

After 10 cycles of regeneration, the resolution rate of carbon dioxide and sulfur dioxide is 90%, and the regeneration efficiency is 93%.

The cotton fiber-based double-layer high amino density fiber-based absorbent material has an antibacterial rate of 99.0% against Staphylococcus aureus, 96.9% against Escherichia coli, and 95.9% against Candida albicans.

Example 5

1. Use bamboo shoot powder as the matrix to prepare the adsorption material, the steps are as follows:

(1) Alkali pretreatment: immerse the bamboo shoot powder in 20wt% NaOH aqueous solution, put it into an ultrasonic shock reactor, and treat it under the condition of ultrasonic power 200W for 1.5h. After the ultrasonic treatment, take it out at a temperature of 50°C Soak it under water for 20 hours, pour off the solution, wash the obtained bamboo shoot powder with water for several times until it becomes neutral, and dry it under vacuum in an oven at 60°C until it reaches a constant weight.

(2) Grafting reaction: mix the bamboo shoot powder fiber obtained in step (1) with 8wt% acrylic acid, control the ratio of the weight of the bamboo shoot powder fiber to the volume of acrylic acid to 1:50, after mixing evenly, add 30% H ₂ O ₂ and 1.5×10 ^-2 g/mL ferrous amine sulfate solution; the volume ratio of the required volume of H ₂ O ₂ to acrylic acid is 0.6:100, and the volume ratio of the required volume of ferrous amine sulfate solution to acrylic acid is 1:5 After reflux reaction at 40°C for 20h, wash with ethanol and filter for 3 times, then wash with water for 5 times, dry in a vacuum oven at 60°C until constant weight to obtain bamboo shoot powder-based grafted fiber.

(3) Amination reaction: Add tetraethylenepentamine to the bamboo shoot powder-based graft fiber obtained in step (2), and the ratio of the weight of the graft fiber to the volume of tetraethylenepentamine is 1:50. The mixture was reacted at 130°C for 8h. After the reaction, soak and wash with water several times, and finally rinse with ethanol, filter with suction, and dry in an oven at 60°C. A bamboo shoot powder-based single-layer amino fiber material is obtained.

(4) Addition reaction: mix the bamboo shoot powder-based single-layer amino fiber material obtained in step (3) with 20%wt acrylamide solution, and control the ratio of the weight of the bamboo shoot powder-based single-layer amino fiber material to the volume of the acrylamide solution 1:50, put it into an ultrasonic shock reactor, treat it under the condition of ultrasonic power 400W for 1h, take it out after the ultrasonic treatment, and continue the reaction in the water bath, the reaction time is 8h, and the reaction temperature is 70°C, so that the fiber will produce Michael Addition reaction, after the reaction is completed, soak and wash with water several times, finally rinse with ethanol, filter with suction, and dry in an oven at 60°C to obtain a bamboo shoot powder-based single-layer amino fiber material after addition.

(5) PEI amide substitution reaction: mix the bamboo shoot powder-based single-layer amino fiber material obtained in step (4) with PEI, and control the ratio of the weight of the bamboo shoot powder-based single-layer amino fiber material to the volume of PEI after the addition is 1:40, the concentration of PEI is 7wt%, the reaction time is 12h, and the reaction temperature is 60°C, so that the fiber and PEI undergo an amide substitution reaction. After the reaction, wash with ethanol to remove excess polyamine reagent and suction filter, and place at 60°C drying in an oven to obtain a bamboo shoot powder-based double-layer high amino density fiber-based adsorption material.

2. After measurement, the adsorption capacity of the bamboo shoot powder-based double-layer high amino density fiber-based adsorption material for CO ₂ is 2.56 mmol CO ₂ /g, and the adsorption capacity for SO ₂ is 106 mg SO ₂ /g.

After 10 cycles of regeneration, the resolution rate of carbon dioxide and sulfur dioxide is 92%, and the regeneration efficiency is 95%.

The antibacterial rate of the bamboo shoot powder-based double-layer high amino density fiber-based absorbent material was 98.4% against Staphylococcus aureus, 96.4% against Escherichia coli, and 95.9% against Candida albicans.

Example 6

1. Using corn cob fiber as the substrate to prepare the adsorption material, the steps are as follows:

(1) Alkali pretreatment: crush the corncob fibers, immerse them in 15wt% NaOH aqueous solution, put them into an ultrasonic shock reactor, and treat them for 1 hour under the condition of ultrasonic power 400W. After the ultrasonic treatment, take them out at a temperature of 50°C Soak for 10 hours under the same conditions, pour off the solution, wash the obtained corn cobs with water for several times until neutral, and vacuum-dry them in an oven at 60°C until they reach constant weight.

(2) Grafting reaction: Mix the corn cob fiber obtained in step (1) with 20wt% acrylonitrile, control the ratio of the weight of the corn cob fiber to the volume of acrylonitrile to 1:40, after mixing evenly, add 30% H ₂ O ₂ and 8×10 ^-3 g/mL ferrous amine sulfate solution; the volume ratio of the required volume of H ₂ O ₂ to acrylonitrile is 0.8:100, the volume ratio of the required volume of ferrous amine sulfate solution to acrylonitrile The ratio is 1:5; after reflux reaction at 70°C for 24 hours, immerse and filter with ethanol for 5 times, then soak and filter with water for 4 times, dry in a 60°C oven under vacuum until constant weight, and obtain corn cob-based grafted fiber .

(3) Amination reaction: Add diethylamine to the corncob-based graft fiber obtained in step (2), and the ratio of the weight of the graft fiber to the volume of diethylamine is 1:40. The mixture was reacted at 100°C for 4h. After the reaction, soak and wash with water several times, and finally rinse with ethanol, filter with suction, and dry in an oven at 60°C. Obtain corncob-based single-layer amino fiber material.

(4) Addition reaction: Mix the corncob-based single-layer amino fiber material obtained in step (3) with 20%wt methyl acrylate solution, and control the weight of the corncob-based single-layer amino fiber material and the volume of the methyl acrylate solution The ratio is 1:30, put it into an ultrasonic shock reactor, and treat it under the condition of ultrasonic power 400W for 1h, take it out after the ultrasonic treatment, and continue the reaction in a water bath, the reaction time is 20h, and the reaction temperature is 70°C. A Michael addition reaction occurs, after the reaction is completed, it is soaked with water for several times, finally rinsed with ethanol, filtered with suction, and dried in an oven at 60°C to obtain a corncob-based single-layer amino fiber material after addition.

(5) PEI amide substitution reaction: Mix the added corncob-based single-layer amino fiber material obtained in step (4) with PEI, and control the weight ratio of the added corncob-based single-layer amino fiber material to PEI volume ratio to 1 :50, the concentration of PEI is 15 wt %, the reaction time is 48h, and the reaction temperature is 60°C, so that the fiber and PEI are subjected to amide substitution reaction. After the reaction, wash with ethanol to remove excess polyamine reagent and suction filter, and place at 60°C drying in an oven to obtain a corncob-based double-layer high amino density fiber-based adsorption material.

2. It has been determined that the above-mentioned corncob-based double-layer high amino density fiber-based adsorption material has an adsorption capacity of 4.25 mmol CO ₂ /g for CO ₂ and an adsorption capacity of 105 mg SO ₂ /g for SO ₂ .

After 10 cycles of regeneration, the resolution rate of carbon dioxide and sulfur dioxide is 93%, and the regeneration efficiency is 96%.

The antibacterial rate of the corncob-based double-layer high amino density fiber-based absorbent material was 99.1% against Staphylococcus aureus, 97.1% against Escherichia coli, and 95.6% against Candida albicans.

Claims (4)

1. a kind of double-deck high amino density Plant fiber's adsorbing material is it is characterised in that prepared by following preparation method：

S1. oxygenation pretreatment：

S11. Plant fiber is placed in 10～20wt% NaOH aqueous solution, 100～400W ultrasonic vibration processes 1～2h；

S12., after supersound process, soak 10～24h in 50 DEG C；

S13. incline solution, and gained fiber is washed with water to neutrality, 60 DEG C of drying；

Described Plant fiber is bagasse, Radix Crotalariae szemoensis powder, maize cob meal, Folium Agaves Sisalanae, straw or cotton fiber；

S2. graft reaction：

S21. it is 1 according to the weight of Plant fiber after oxygenation pretreatment with the ratio of the volume of unsaturated grafted monomers solution:10～ 1:50, both are mixed；The concentration of described unsaturation grafted monomers solution is 2～20wt%；

S22. according to H₂O₂Volume ratio with unsaturated grafted monomers solution is 0.2:100～2:100, the solution after mixing to S21 Middle addition initiator H₂O₂；

S23. the volume ratio according to ferrous sulfate amine aqueous solution and unsaturated grafted monomers solution is 1:5, the solution after processing to S22 Middle addition ferrous sulfate amine aqueous solution；The concentration of described ferrous sulfate amine aqueous solution is 1 × 10^-3～1 × 10^-1g/mL；

S24., after reaction 1～24h under the conditions of 30～80 DEG C, embathe sucking filtration 2～5 times with ethanol, then wash sucking filtration 2～5 with water logging Secondary, 60 DEG C of vacuum dryings, obtain graft fibres；

Described unsaturation grafted monomers solution be：Acrylamide solution, methyl acrylate solution, acrylonitrile solution, acrylic acid are molten Liquid or glycidyl methacrylate solution；S3. aminating reaction：

S31. according to polyamines and graft fibres weight than for 2:1～100:1, graft fibres add polyamines；

S32. under the conditions of 100～150 DEG C react 6～10h, washed 2～5 times with water logging, then use alcohol flushing, sucking filtration, 60 DEG C dry Dry, obtain monolayer amino plant fiber-based material；

Described polyamines is ethylenediamine, diethylamine, diethylenetriamine, triethylene tetramine, TEPA or pentaethylene hexamine；

S4. additive reaction：

S41. it is 1 according to the weight of monolayer amino plant fiber-based material with the ratio of the volume of unsaturated grafted monomers solution: 10～1:60, both are mixed, the concentration of described unsaturation grafted monomers solution is 5～50wt%；

S42., after 100～400W ultrasonic lower process 1～2h, 10～60 DEG C of water-baths are reacted 1～24h；

S43. washed 2～5 times with water logging, finally use alcohol flushing, sucking filtration, 60 DEG C of drying, obtain the monolayer amino plant after addition Fiber-based material；

S5.PEI amide substitution reaction：

S51. the ratio according to the weight of the monolayer amino plant fiber-based material after addition and the volume of polyethyleneimine is 1:5 ～1:60, both are mixed, the concentration of described polyethyleneimine is 5～15wt%；

S52. react 10～48h at 20～60 DEG C, make fiber and polyethyleneimine carry out amide substitution reaction；

S53. washing with alcohol removes unnecessary polyethyleneimine, sucking filtration, 60 DEG C of drying, obtains double-deck high amino density Plant fiber Adsorbing material；

Wherein, described Plant fiber is bagasse, Radix Crotalariae szemoensis powder, maize cob meal, Folium Agaves Sisalanae, straw or cotton fiber；

The heat decomposition temperature of this adsorbing material, more than 300 DEG C, has anti-microbial property and the adsorbing and trapping performance to sour gas； This adsorbing material, after adsorbed gas, can regenerate through thermal desorption.

2. application in terms of absorbing acid gases for the double-deck high amino density Plant fiber's adsorbing material described in claim 1.

3. described in claim 1, double-deck high amino density Plant fiber's adsorbing material in Wood-plastic material antibacterial or prevents the wood fiber The application of aspect of going mouldy.

4. apply according to claim 3 it is characterised in that being to be applied to anti-Staphylococcus aureus, escherichia coli or white Color candidiasises.