Hydrochloric acid assisted alpha-amylase modified hawthorn residue adsorbent, preparation method and application thereof

Abstract

The application belongs to the technical field of hawthorn residue adsorbent preparation, and discloses a hawthorn residue adsorbent modified by hydrochloric acid and alpha-amylase, a preparation method and application thereof, and the preparation method comprises the following steps: after the sample hawthorn is washed, the sample hawthorn is placed in a drying box for drying, and then the sample hawthorn is soaked and modified by using an alkali heat scalding method. The hawthorn residue discarded by a hawthorn processing factory is used as a raw material, the hawthorn residue is chemically modified by using an alkali heat scalding treatment method and a hydrochloric acid assisted enzymolysis method, and through a large number of comparative experiments, the optimal extraction conditions of the hawthorn residue, the optimal adsorption particle size of the hawthorn residue and the added mass are determined. Compared with the prior art, the hawthorn residue extracted by using the process has a stronger adsorption rate for nicotine, meanwhile, the raw material used in the process fully realizes the transformation of waste into treasure, and the production cost can be greatly reduced, and obvious progress is achieved.

Description

Technical Field

[0001] This invention relates to the field of hawthorn residue adsorbent preparation technology, and more specifically to a hydrochloric acid-assisted α-amylase modified hawthorn residue adsorbent, its preparation method, and its application. Background Technology

[0002] Cigarette filters can reduce the damage to smokers' health caused by harmful substances in cigarettes. They can filter out harmful substances in cigarettes to a certain extent. Currently, the main component of cigarette filters on the market is cellulose acetate. However, my country mainly relies on imports to supplement domestic demand for cellulose acetate, and its filtering effect is relatively limited. Therefore, from a long-term perspective, it is necessary to find a new filter material that can replace cellulose acetate as soon as possible.

[0003] Hawthorn is a drupe fruit. In traditional Chinese medicine, dried hawthorn is often used as a medicine to invigorate the spleen and stomach, promote digestion, and resolve phlegm. Compared with other fruits, hawthorn contains a relatively high amount of dietary fiber, including pectin, cellulose, and lignin, with a total dietary fiber content reaching 3.1%. This invention starts with hawthorn residue, which is low-cost and readily available, and uses chemical modification methods to extract water-insoluble dietary fiber from hawthorn. The optimal conditions for the extraction process are determined to compensate for the shortcomings of existing extraction methods and to solve the problem of low nicotine adsorption rate of hawthorn residue extracted by existing methods. Summary of the Invention

[0004] In view of this, the present invention provides a hydrochloric acid-assisted α-amylase modified hawthorn residue adsorbent, its preparation method and application, to solve the technical problems encountered in the background art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A method for preparing a hydrochloric acid-assisted α-amylase-modified hawthorn residue adsorbent includes the following steps:

[0007] (1) After washing the hawthorn samples, they were dried in a drying oven and then modified by soaking in an alkaline hot scalding method.

[0008] (2) Add α-amylase and water to the hawthorn sample after alkaline heat treatment, mix thoroughly, let stand, then take out the hawthorn sample, rinse with running water after water bath until neutral;

[0009] (3) Place the hawthorn sample treated in step (2) into a hydrochloric acid solution for water bath treatment. After the water bath is completed, rinse with running water until neutral.

[0010] (4) The hawthorn sample treated in step (3) is dried in a drying oven, then crushed and sieved to obtain the adsorbent.

[0011] Preferably, the hawthorn sample mentioned in step (1) is hawthorn residue produced by a food processing plant.

[0012] Preferably, the drying temperature in step (1) is 70°C.

[0013] Preferably, in step (2), the mass ratio of sample hawthorn to α-amylase is 20:1, and the amount of water added is 10ml of water per 1g sample hawthorn.

[0014] Preferably, the water bath in step (2) is: placing the hawthorn sample in a water bath and bathing it at 70°C for 30 minutes.

[0015] Preferably, the hydrochloric acid solution in step (3) has a mass fraction of 10%, and the water bath temperature is 98°C.

[0016] Preferably, the drying temperature in step (4) is 80°C; and the sieving is done through a 40-mesh sieve.

[0017] Preferably, the drying oven is an electric heating forced-air drying oven, and the water bath is a digital display constant temperature water bath.

[0018] Another objective of this invention is to apply the hydrochloric acid-assisted α-amylase-modified hawthorn residue adsorbent prepared by the above method in the purification of nicotine in flue gas.

[0019] As can be seen from the above technical solution, compared with the prior art, the present invention has the following beneficial effects:

[0020] This invention uses hawthorn residue discarded from hawthorn processing plants as raw material. It employs alkaline hot blanching and hydrochloric acid-assisted enzymatic hydrolysis to chemically modify the residue. Through numerous comparative experiments, the optimal extraction conditions, optimal adsorption particle size, and optimal addition mass of the hawthorn residue were determined. This results in hawthorn residue extracted using the process of this invention exhibiting a stronger adsorption rate for nicotine compared to existing technologies. Furthermore, the raw materials used in this process fully realize the transformation of waste into valuable resources, significantly reducing production costs and demonstrating substantial progress. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0022] Figure 1 This is a graph showing the effect of hydrochloric acid mass fraction on the adsorption effect of hawthorn residue in this invention;

[0023] Figure 2 This is a graph showing the effect of slag particle size on the nicotine adsorption effect in flue gas according to the present invention.

[0024] Figure 3 This is a graph showing the effect of the amount of this invention added on the nicotine adsorption effect in flue gas;

[0025] Figure 4 This is a lateral comparison diagram of different adsorbent materials of the present invention;

[0026] Figure 5 This is the Fourier transform infrared spectrum of the present invention;

[0027] Figure 6 This is the X-ray diffraction pattern of the present invention. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Example 1

[0030] Adsorbent preparation process:

[0031] 1. Wash the hawthorn residue, set the drying oven to 70℃, put in the washed hawthorn residue, dry it, and weigh out 20g hawthorn residue into 5 portions.

[0032] 2. Add 1g of α-amylase to each of the 5 hawthorn residues, then add 200ml of distilled water and let stand for 2 hours;

[0033] 3. Place the soaked hawthorn residue into a water bath and heat at 70℃ for 30 minutes;

[0034] 4. Filter out the hawthorn residue and rinse under running water until neutral;

[0035] 5. Place the five portions of hawthorn residue into hydrochloric acid solutions with mass fractions of 5%, 10%, 15%, 20%, and 25%, respectively, and incubate them in a water bath at 98°C for 1 hour.

[0036] 6. Rinse 5 portions of hawthorn residue under running water until neutral;

[0037] 7. After rinsing, place the hawthorn residue in an 80℃ drying oven to dry;

[0038] 8. Use a small pulverizer to pulverize the dried hawthorn residue. After sieving five portions of hawthorn residue through a 40-mesh sieve, weigh out 0.1g of each portion as an adsorbent.

[0039] The adsorption rate determination process of the adsorbent prepared in this embodiment is as follows:

[0040] 1. Use sterilized tweezers to remove the cellulose acetate from the cigarette, then cut off a 1.5cm piece of cellulose acetate to make an experimental cigarette.

[0041] 2. Place the five portions of 0.1g hawthorn residue obtained above into the cigarette from which the cellulose acetate has been removed, and then add a 1.5cm length of cellulose acetate.

[0042] 3. Place the cigarette prepared in the above steps onto the adsorption device and clamp it with a water-stop clamp. Turn on the vacuum pump and wait until the vacuum pump pressure reaches 0.01MPa (at which point small bubbles will appear). Then, open the water-stop clamp, light the cigarette, and turn off the vacuum pump and water-stop clamp when the cigarette has burned out. Allow the smoke to completely dissolve in 150mL of distilled water, pour it into a 250mL volumetric flask, and let it stand for 20 minutes.

[0043] 4. Pour into a beaker, add 5g NaOH and dissolve completely, then add 0.0277g potassium permanganate. Transfer to a volumetric flask and bring the volume to 250ml to achieve a sodium hydroxide concentration of 0.5mol / L. The potassium permanganate concentration equilibrium is 7*10⁻⁶. -4 mol / L;

[0044] 5. Incubate the hawthorn residue in a 100℃ water bath for 8 minutes, cool to room temperature, filter the supernatant, add it to a cuvette, and measure the absorbance at a wavelength of 612nm. Repeat each experiment three times, take the average value, record the data, and calculate the adsorption rates of hawthorn residue in water baths with different mass fractions (5%, 10%, 15%, 20%, 25%) of hydrochloric acid: 40.1%; 42%; 32.9%; 30.9%; 29.5%.

[0045] Formula for calculating the adsorption rate of nicotine in cigarette smoke by hawthorn residue:

[0046] Adsorption rate = (M1 - M1') / M1

[0047] Where: M1 is the total amount of nicotine in the solution of the filtration device;

[0048] M1' represents the nicotine content in the solution of the filtration device during each experiment.

[0049] Example 2

[0050] Adsorbent preparation process:

[0051] 1. Wash the hawthorn residue, set the drying oven to 70℃, put in the washed hawthorn residue, dry it, and weigh out 20g of hawthorn residue.

[0052] 2. Add 1g of α-amylase to each of the hawthorn residues, then add 200ml of distilled water and let stand for 2 hours;

[0053] 3. Place the soaked hawthorn residue into a water bath and heat at 70℃ for 30 minutes;

[0054] 4. Filter out the hawthorn residue and rinse under running water until neutral;

[0055] 5. Place the hawthorn residue in 10% hydrochloric acid and bathe it in a water bath at 98℃ for 1 hour;

[0056] 6. Rinse the hawthorn residue after the water bath under running water until it becomes neutral;

[0057] 7. After rinsing, place the hawthorn residue in an 80℃ drying oven to dry;

[0058] 8. Use a small pulverizer to pulverize the dried hawthorn residue. After sieving the pulverized hawthorn residue through 8-mesh, 18-mesh, 40-mesh, 60-mesh and 80-mesh sieves respectively, take 0.1g of each hawthorn residue as an adsorbent for later use.

[0059] The adsorption rate determination process of the adsorbent prepared in this embodiment is as follows:

[0060] 1. Use sterilized tweezers to remove the cellulose acetate from the cigarette, then cut off a 1.5cm piece of cellulose acetate to make an experimental cigarette.

[0061] 2. Place the five portions of 0.1g hawthorn residue obtained above into the cigarette from which the cellulose acetate has been removed, and then add a 1.5cm length of cellulose acetate.

[0062] 3. Place the cigarette prepared in the above steps onto the adsorption device and clamp it with a water-stop clamp. Turn on the vacuum pump and wait until the vacuum pump pressure reaches 0.01MPa (at which point small bubbles will appear). Then, open the water-stop clamp, light the cigarette, and turn off the vacuum pump and water-stop clamp when the cigarette has burned out. Allow the smoke to completely dissolve in 150mL of distilled water, pour it into a 250mL volumetric flask, and let it stand for 20 minutes.

[0063] 4. Pour into a beaker, add 5g NaOH and dissolve completely, then add 0.0277g potassium permanganate. Transfer to a volumetric flask and bring the volume to 250ml to achieve a sodium hydroxide concentration of 0.5mol / L. The potassium permanganate concentration equilibrium is 7*10⁻⁶. -4 mol / L;

[0064] 5. Incubate the mixture in a 100℃ water bath for 8 minutes, cool to room temperature, filter the supernatant, add it to a cuvette, and measure the absorbance at a wavelength of 612 nm. Repeat each experiment three times, take the average value, record the data, and calculate the adsorption rates of hawthorn residue in a water bath under hydrochloric acid after sieving with different mass fractions and different sieves (8 mesh; 18 mesh; 40 mesh; 60 mesh; 80 mesh): 40.6%; 41.1%; 44.1%; 38.6%; 39.6%. See the table below for details.

[0065] Table 1. Multiple comparisons of adsorption rates for different slag particle sizes

[0066]

[0067] Example 3

[0068] Adsorbent preparation process:

[0069] 1. Wash the hawthorn residue, set the drying oven to 70℃, put in the washed hawthorn residue, dry it, and weigh out 20g of hawthorn residue.

[0070] 2. Add 1g of α-amylase to each of the hawthorn residues, then add 200ml of distilled water and let stand for 2 hours;

[0071] 3. Place the soaked hawthorn residue into a water bath and heat at 70℃ for 30 minutes;

[0072] 4. Filter out the hawthorn residue and rinse under running water until neutral;

[0073] 5. Place the hawthorn residue separately into 10% hydrochloric acid and bathe in a water bath at 98℃ for 1 hour;

[0074] 6. Rinse the hawthorn residue after the water bath under running water until it becomes neutral;

[0075] 7. After rinsing, place the hawthorn residue in an 80℃ drying oven to dry;

[0076] 8. Use a small pulverizer to pulverize the dried hawthorn residue. After sieving the hawthorn residue through a 40-mesh sieve, weigh out 0.05g, 0.1g, 0.15g, 0.2g, and 0.25g of the hawthorn residue respectively as adsorbents for later use.

[0077] The adsorption rate determination process of the adsorbent prepared in this embodiment is as follows:

[0078] 1. Use sterilized tweezers to remove the cellulose acetate from the cigarette, then cut off a 1.5cm piece of cellulose acetate to make an experimental cigarette.

[0079] 2. Place the five portions of hawthorn residue prepared above (0.05g, 0.1g, 0.15g, 0.2g, and 0.25g) into the cigarette from which the cellulose acetate has been removed, and then add a 1.5cm piece of cellulose acetate.

[0080] 3. Place the cigarette prepared in the above steps onto the adsorption device and clamp it with a water-stop clamp. Turn on the vacuum pump and wait until the vacuum pump pressure reaches 0.01MPa (at which point small bubbles will appear). Then, open the water-stop clamp, light the cigarette, and turn off the vacuum pump and water-stop clamp when the cigarette has burned out. Allow the smoke to completely dissolve in 150mL of distilled water, pour it into a 250mL volumetric flask, and let it stand for 20 minutes.

[0081] 4. Pour into a beaker, add 5g NaOH and dissolve completely, then add 0.0277g potassium permanganate. Transfer to a volumetric flask and bring the volume to 250ml to achieve a sodium hydroxide concentration of 0.5mol / L. The potassium permanganate concentration equilibrium is 7*10⁻⁶. -4 mol / L;

[0082] 5. Incubate the solution in a 100℃ water bath for 8 minutes, cool to room temperature, filter the supernatant, add it to a cuvette, and measure the absorbance at 612nm. Repeat each experiment three times, take the average value, record the data, and calculate the adsorption rates after adding different masses (0.05g, 0.1g, 0.15g, 0.2g, 0.25g) of hawthorn residue: 40.6%; 43.5%; 42.5%; 37.2%; 34.8%, respectively. See the table below for details.

[0083] Table 2. Effect of different addition amounts on adsorption rate (Duncan method)

[0084]

[0085]

[0086] Example 4

[0087] Equal masses of hawthorn residue (prepared using the method of this invention), diatomaceous earth, activated carbon, and unmodified hawthorn residue were weighed out and placed into cigarettes. Then, 1.5 cm of cellulose acetate was added to prepare the cigarettes. Other experimental conditions were the same as in the three examples above. Adsorption was performed using a vacuum filtration device. After heating in a water bath and allowing to stand at room temperature, the absorbance of the upper filtrate was repeatedly measured. The average adsorption rate of each material was obtained, as shown in the table below.

[0088] Table 3 Adsorption rate analysis of different materials (Duncan method)

[0089]

[0090] As shown in the table above, the hawthorn pomace treated with alkaline hot blanching and hydrochloric acid water bath showed the strongest nicotine adsorption capacity, while the untreated hawthorn pomace showed the weakest nicotine adsorption capacity. This is consistent with the experimental results showing a lower pomace yield after optimization. In comparison, commercially available activated carbon did not perform as well as diatomaceous earth, and cellulose acetate was even worse. The variance analysis table of the nicotine adsorption capacity of different materials obtained from the experiment is as follows:

[0091] Table 4. Analysis of Variance of Nicotine Adsorption Rate of Different Materials

[0092]

[0093]

[0094] In addition, the characterization analysis and verification involved in the above four embodiments employ the following three types and methods:

[0095] (1) Fourier Transform Infrared Spectrometer: Add a small amount of potassium bromide to a mortar, take a small amount of the optimal chemically modified residue, grind it thoroughly with potassium bromide, mix well, pour it into a tablet, press it on a tablet press, wait for the tablet to become transparent, and scan it under an infrared spectrometer to measure the spectrum. Then take a small amount of the original hawthorn residue and the residue that has adsorbed nicotine, and repeat the experiment. Determine the changes in the properties of the residue before and after adsorption and before and after modification based on the spectra of different residues. Specifically, as follows: Figure 5 (A: Raw residue without chemical modification; B: Hawthorn residue after chemical modification; C: Optimized hawthorn residue after nicotine adsorption) as shown:

[0096] Original residue: 3411.80cm -1 The point is the -OH stretching vibration, 1630.20 cm. -1 The stretching vibration of the amide NH group is present at this location.

[0097] Optimal sludge: 3422.89cm -1 The point is the -OH stretching vibration, 1644.18 cm. -1 The vibrations at this point represent the stretching vibrations of the amide NH group. The positions of the vibrational peaks for -OH and NH are shifted to the left compared to the original slag, indicating that the modification treatment increased the number of -OH and NH groups.

[0098] After adsorption: -OH stretching vibration at 340.61 cm⁻¹, and at 1644.18 cm⁻¹. -1 The NH group at the position represents stretching vibration, and the -OH and NH groups are reduced compared to when they are not adsorbed, indicating that they participate in the adsorption of nicotine.

[0099] In addition, there are also peak changes in C=O, CH, and COC groups. These groups play a role in the adsorption process, indicating that the adsorption of nicotine by hawthorn residue is mainly a chemical adsorption process.

[0100] (2) Elemental analyzer: Take 3mg of standard reagent, place it on tin foil, and wrap it into a small square. Then weigh 3mg each of the original residue, treated residue, and nicotine-adsorbed residue, and wrap them into small squares as well. Then put the sample and the test sample into the instrument for detection. By analyzing the data obtained, find the changes in elements after adsorption after treatment. The specific results are shown in the table below:

[0101] Table 5 Comparison of Element Content

[0102]

[0103] From the results in the table above, we can see that the C, H, and N element contents of the hawthorn residue changed after treatment and adsorption. This indicates that the treatment may have changed the number of polar groups such as C=N groups and COOH in the material, which played an important role in the adsorption of nicotine. The H element content of the optimized hawthorn residue increased, indicating that the treatment increased the number of carboxyl and hydroxyl groups in the hawthorn residue. These groups played a significant role in the adsorption of nicotine.

[0104] (3) X-ray diffraction: Characterized by the interplanar spacing and relative intensity of diffraction lines. The interplanar spacing and relative intensity of diffraction lines of any substance are a necessary reflection of its structure. These can be used to identify the phases of a substance. Raw residue, chemically modified hawthorn residue, and adsorbed residue were prepared into slides and tested in the instrument. The crystallinity was determined based on the peak values, thereby analyzing the structural properties. Specific analytical results are as follows: Figure 6 (A: Optimized hawthorn pomace after nicotine adsorption; B: Chemically modified hawthorn pomace; C: Original hawthorn pomace;) as shown:

[0105] Analysis revealed a strong characteristic diffraction peak at 2θ = 22.5°, representing the crystalline region of cellulose. The original hawthorn residue exhibited the smallest diffraction peak, followed by the treated residue, and then the largest after adsorption. The increased crystallinity and more stable physical structure throughout the treatment and adsorption processes indicate that physical adsorption also occurred during the entire adsorption process.

[0106] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0107] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0108] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing a nicotine hydrochloride-assisted α-amylase-modified hawthorn residue adsorbent for purifying flue gas, characterized in that, Includes the following steps: (1) After washing the hawthorn samples, they were dried in a drying oven and then modified by soaking in an alkaline hot scalding method; (2) After the sample hawthorn was modified by alkaline heat, add α-amylase and water and mix thoroughly. Let it stand, then take out the sample hawthorn, rinse it with running water after water bath until it is neutral; the mass ratio of sample hawthorn to α-amylase in step (2) is 20:1, and the amount of water added is 10ml of water per 1g sample hawthorn. The water bath is to place the sample hawthorn in a water bath pot and bathe it at 70℃ for 30min. (3) Place the hawthorn sample treated in step (2) into a hydrochloric acid solution for water bath treatment. After the water bath is completed, rinse with running water until neutral. The hydrochloric acid solution has a mass fraction of 10%, and the water bath temperature is 98°C. (4) The hawthorn sample treated in step (3) is placed in a drying oven and dried, then crushed and sieved to obtain the adsorbent. The sieving is through a 40-mesh sieve.

2. The preparation method according to claim 1, characterized in that, The hawthorn sample mentioned in step (1) is hawthorn residue produced by a food processing plant.

3. The preparation method according to claim 1, characterized in that, The drying temperature in step (1) is 70°C.

4. The preparation method according to claim 1, characterized in that, The drying temperature in step (4) is 80°C.

5. The preparation method according to claim 1, characterized in that, The drying oven is an electric heating forced-air drying oven, and the water bath is a digital display constant temperature water bath.

6. A hydrochloric acid-assisted α-amylase-modified hawthorn residue adsorbent, characterized in that, It is prepared by the preparation method described in any one of claims 1-5.

7. The application of the hydrochloric acid-assisted α-amylase-modified hawthorn residue adsorbent as described in claim 6 in the purification of nicotine in flue gas.

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