Modified highland barley vinasse, air purifying agent and application

Abstract

The invention belongs to the technical field of PM2.5 adsorbents, and particularly relates to modified highland barley vinasse, an air purifying agent and application thereof.The modified highland barley vinasse is obtained by soaking highland barley vinasse in an ethyl acetate solution and then modifying the highland barley vinasse through hemicellulase, so that the content of hydroxyl and carboxyl in the highland barley vinasse is increased. The air purifying agent takes the modified highland barley vinasse as a unique effective component, the PM2.5 removal rate of the air purifying agent is up to 16.18%, the removal rate of the modified highland barley vinasse subjected to 7 times of cyclic adsorption is equivalent, and the air purifying agent can be repeatedly utilized.

Description

Technical Field

[0001] The present invention belongs to PM 2.5 The technical field of adsorbents specifically relates to a modified highland barley lees, an air purifier and applications. Background Art

[0002] Highland barley is widely planted in the plateau areas of my country. It is an annual herbaceous plant of the Poaceae family and the genus Hordeum. Highland barley has strong health benefits and has the characteristics of three highs and two lows in nutritional value. Highland barley wine is a traditional drink in the Qinghai-Tibet Plateau and is also the main raw material for brewing highland barley wine. During the brewing of highland barley wine, a large amount of highland barley lees is produced as a by-product. Highland barley lees contain a large amount of protein, cellulose, starch and vitamins. Highland barley lees are currently widely used to feed livestock or pile up agricultural fertilizers. This phenomenon not only causes a great waste of resources, but also pollutes the environment.

[0003] PM 2.5 PM refers to atmospheric particles with a diameter of less than 2.5 μm in aerodynamics, which are called respirable particles. 2.5 It is mainly caused by the public's daily pollution of the environment, which leads to the emission of a large amount of harmful gases into the atmosphere. 2.5 Volatile substances produced by burning coal and gasoline, exhaust gas from diesel vehicles, burning of straw, firewood and garbage piles. In addition, secondary particulate matter produced by volatile organic compounds is also a source of PM. 2.5 The main source of PM2.5. 2.5 There are many adsorbents, such as activated carbon for PM 2.5 For adsorption, macroporous adsorption resins are also used for PM 2.5 For adsorption, both of the above adsorbents have the ability to adsorb PM 2.5 The problem of poor adsorption effect. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a modified highland barley lees, an air purifier and an application thereof, wherein the highland barley lees are modified to obtain an air purifier for PM 2.5 Modified highland barley grains with good adsorption effect.

[0005] In order to achieve the above object, the technical solution of the present invention is as follows.

[0006] The first aspect of the present invention provides a modified highland barley vinasse, wherein the modified highland barley vinasse is prepared by the following method:

[0007] The hot-steamed highland barley lees are soaked in an ethyl acetate solution for 17 to 31 hours, a hemicellulase solution is added, the mixture is reacted in a water bath at 50 to 55 degrees Celsius for 28 to 30 minutes, and the enzyme is inactivated at 70 to 75 degrees Celsius for 18 to 20 minutes to obtain enzyme-inactivated highland barley lees;

[0008] The enzyme-inactivated highland barley lees are rinsed to neutrality, dried, and crushed to obtain the modified highland barley lees; the modified highland barley lees are used for PM 2.5 Adsorption;

[0009] The concentration of the ethyl acetate solution is 0.02 mol / L to 0.18 mol / L;

[0010] The concentration of the hemicellulase solution is 0.32 g / L to 0.48 g / L.

[0011] The invention uses an ethyl acetate solution with a concentration of 0.02 mol / L to 0.18 mol / L to assist a hemicellulase solution with a concentration of 0.32 g / L to 0.48 g / L to modify highland barley lees. In the modification process, the highland barley lees are soaked in the ethyl acetate solution for 17 to 31 hours and reacted at a temperature of 50 to 55°C for 28 to 30 minutes when the hemicellulase solution is added, so that the highland barley lees have a loose, porous and multi-fold structure, and the contents of hydroxyl and carboxyl groups in the highland barley lees are increased. The obtained modified highland barley lees have a good PM resistance. 2.5 It has a good adsorption effect. In addition, during the enzyme inactivation process, by controlling the enzyme inactivation temperature at 70°C to 75°C for 18min to 20min, it can ensure that the enzyme inactivation treatment is completed without destroying the structure of the modified highland barley lees. The present invention makes full use of highland barley lees as PM 2.5 Adsorbents for PM 2.5 The removal rate is as high as 16.18%.

[0012] In another preferred embodiment, the particle size of the modified highland barley grains is 40 mesh to 80 mesh.

[0013] In another preferred embodiment, the mass volume ratio of the highland barley grains to the hemicellulase solution is 10kg:50L-55L.

[0014] In another preferred embodiment, the steaming time is 18 min to 20 min.

[0015] The second aspect of the present invention provides an air purifier, wherein the air purifier contains the modified highland barley lees as the only effective ingredient.

[0016] The third aspect of the present invention provides the air purifier for preparing a method for removing PM in the air. 2.5Application in air purifiers.

[0017] A fourth aspect of the present invention provides a PM 2.5 The modified highland barley lees are placed in a PM-containing 2.5 In the gas, the modified highland barley lees are used to treat PM 2.5 Adsorption to remove PM from the gas 2.5 .

[0018] In another preferred embodiment, the quality of the modified highland barley vinasse is 2.5 The ratio of the adsorption amount is 3g:79μg~81μg.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] (1) The modified highland barley lees in the present invention has an effect on PM 2.5 The removal rate of PM was as high as 16.18%, and after 7 cycles of adsorption, the removal rate of PM 2.5 The present invention adopts ethyl acetate to assist hemicellulase, so that highland barley lees have a loose, porous and wrinkled structure, and increases the content of hydroxyl and carboxyl groups in highland barley lees, thereby greatly enhancing the PM removal rate. 2.5 adsorption capacity.

[0021] (2) In the present invention, the soaking time of highland barley vinasse in the ethyl acetate solution and the concentration of the hemicellulase solution are controlled to make the modified highland barley vinasse have good PM 2.5 When the modified highland barley lees in the present invention is used as the only effective ingredient of the air purifier, only 3g of modified highland barley lees is needed to remove PM 2.5 The concentration is 500 μg / m 3 In the air environment, PM after adsorption for 50 minutes 2.5 The removal rate can reach 16.18%. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is the result graph of the effect of hemicellulase concentration and soaking time on the removal rate.

[0023] Figure 2 is the effect of NaOH concentration on PM 2.5 Impact results diagram.

[0024] Figure 3 is the effect of hemicellulase concentration on PM 2.5 Impact results diagram.

[0025] Figure 4 is the effect of neutral protease concentration on PM 2.5 Impact results diagram.

[0026] Figure 5 The effect of α-amylase concentration on PM 2.5 impact.

[0027] Figure 6 To study the effect of particle size of modified highland barley distiller's grains on the adsorption effect.

[0028] Figure 7 The effect of the amount of modified highland barley grains added on the adsorption effect.

[0029] Figure 8 For PM 2.5 Effect of initial concentration on adsorption efficiency.

[0030] Fig. 9 The influence of adsorption on adsorption effect.

[0031] Fig.10 The effect of adsorption time on the adsorption effect.

[0032] Fig.11 The infrared spectra of different highland barley lees are shown in Figure a. The original highland barley lees are shown in Figure b. The modified highland barley lees are shown in Figure c. 2.5 Spectrum of modified highland barley grains.

[0033] Fig.12 The scanning electron microscope images of different highland barley lees, among which A is the original highland barley lees image; B is the modified highland barley lees image; C is the PM adsorbed 2.5 Spectrum of modified highland barley grains.

[0034] Fig.13 For PM 2.5 Adsorption isotherm diagram.

[0035] Fig.14 This is the linear Langmuir adsorption isotherm diagram.

[0036] Fig.15 This is a linear Freundlich adsorption isotherm diagram.

[0037] Fig.16 For PM 2.5 The adsorption kinetics curve.

[0038] Fig.17 This is a pseudo-first-order rate equation curve.

[0039] Fig.18 This is a graph of the pseudo-second-order rate equation.

[0040] Fig.19 This is the relationship between temperature and adsorption amount.

[0041] Fig. 20 PM adsorption by highland barley lees 2.5 Thermodynamic curve diagram.

[0042] Fig.21 The different adsorbents for PM 2.5 The adsorption results are shown in Figure 2.

[0043] Fig. 22 This is the result graph of the adsorption times of modified highland barley grains. DETAILED DESCRIPTION

[0044] The following will be combined with the specific embodiments of the present invention to clearly and completely describe the technical solutions in the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] The methods described in the embodiments of the present invention are conventional methods unless otherwise specified. The materials, reagents, etc. used can be obtained from commercial sources unless otherwise specified.

[0046] In the prior art, activated carbon or macroporous adsorption resin is usually used to adsorb PM 2.5 However, the adsorption effect is not ideal. Current research results show that highland barley wine grains are mainly used for fertilizer, vinegar brewing, protease extraction, and various organic acids and xylitol produced from fermentation. These methods will result in high costs and complicated extraction processes. In actual production, using wine grains as base fertilizer is still the most widely used and feasible method at home and abroad. This treatment method has many disadvantages, low resource utilization, and the product does not achieve high added value. Therefore, it is necessary to study the adsorption of PM2.5 in the atmosphere by highland barley wine grains. 2.5 , is one of the effective ways to achieve high added value of highland barley distiller's grains.

[0047] The invention uses highland barley lees as raw material and adopts a method of ethyl acetate-assisted hemicellulase to modify the highland barley lees to obtain a PM 2.5 Modified highland barley lees with good adsorption effect on PM 2.5 The adsorption effect is better than that of activated carbon and macroporous adsorption resin in the prior art.

[0048] In the following examples, highland barley lees were collected in Tibet.

[0049] Ethyl acetate was purchased from Tianjin Yongda Chemical Reagent Co., Ltd., hemicellulase and neutral protease were purchased from Nanning Pangbo Bioengineering Co., Ltd.; diatomaceous earth, activated carbon and bamboo charcoal were purchased from Tianjin Ruijinte Chemical Co., Ltd., macroporous adsorption resin AB-8 was purchased from Donghong Chemical Co., Ltd., and α-amylase was purchased from Xingtai Wanda Bioengineering Co., Ltd.

[0050] Example 1

[0051] A method for preparing modified highland barley distiller's grains comprises the following steps:

[0052] S1. Steam 20 g of highland barley lees in boiling water for 20 min, and then soak them in 0.1 mol / L ethyl acetate solution for 24 h to obtain ester-treated highland barley lees.

[0053] S2. Mix the ester-treated highland barley lees with 0.1 g / L hemicellulase solution in a mass volume ratio of 10 g:50 mL, bathe in a 50° C. water bath for 30 min, inactivate the enzyme at 70° C. for 20 min, take out and rinse to neutrality, dry at 80° C. for 24 h, and crush to obtain 40-mesh modified highland barley lees.

[0054] Example 2

[0055] A method for preparing modified highland barley distiller's grains comprises the following steps:

[0056] S1. Steam 15 g of highland barley lees in boiling water for 20 min, and then soak them in 0.02 mol / L ethyl acetate solution for 17 h to obtain ester-treated highland barley lees.

[0057] S2. Mix the ester-treated highland barley lees with 0.32 g / L hemicellulase solution in a mass volume ratio of 10 g:55 mL, bathe in a 55° C. water bath for 28 min, inactivate the enzyme at 75° C. for 18 min, take out, rinse to neutrality, dry at 80° C. for 24 h, and crush to obtain 60-mesh modified highland barley lees.

[0058] Example 3

[0059] A method for preparing modified highland barley distiller's grains comprises the following steps:

[0060] S1. Steam 18 g of highland barley lees in boiling water for 20 min, and then soak them in 0.1 mol / L ethyl acetate solution for 17 h to obtain ester-treated highland barley lees.

[0061] S2. Mix the ester-treated highland barley lees with 0.1 g / L hemicellulase solution in a mass volume ratio of 10 g:50 mL, bathe in a 55°C water bath for 28 min, inactivate the enzyme at 75°C for 18 min, take out and rinse to neutrality, dry at 80°C for 24 h, and crush to obtain 80-mesh modified highland barley lees.

[0062] In order to further illustrate the adsorption effect of the modified highland barley lees in the present invention, the following experiments were conducted.

[0063] 1. Optimization of preparation conditions of modified highland barley lees

[0064] 1) The key factors in the ethyl acetate-assisted hemicellulase method related to the removal rate of highland barley grains adsorbent were further optimized using quadratic regression orthogonal rotation.

[0065] The key factors were the initial concentration of hemicellulase, the initial concentration of ethyl acetate, and the soaking time. The optimal adsorption conditions of each influencing factor were obtained by calculation and set to level 0. A three-factor five-level coding table was compiled, as shown in Table 1.

[0066] Table 1 Coding table of three factors and five levels

[0067]

[0068] According to the three-factor five-level coding table, 23 highland barley lees adsorbents were prepared and the PM 2.5 The concentration was kept constant at 500 μg / m 3 When the adsorbent is placed in a closed box at room temperature for a certain period of time, the values ​​are recorded and the removal rate is calculated as shown in Table 2, and the data is analyzed using DPS software.

[0069] Table 2 Three-factor quadratic regression orthogonal rotation combination design table

[0070]

[0071]

[0072] 1) ANOVA: The ANOVA of highland barley grains processed by DPS software is shown in Table 3.

[0073] Table 3 ANOVA table

[0074] Source of variation SS df MS F P <![CDATA[X1]]> 0.3477 1 0.3477 0.8933 0.3618 <![CDATA[X2]]> 1.0846 1 1.0846 2.7865 0.1190 <![CDATA[X3]]> 0.0383 1 0.0383 0.0985 0.7586 <![CDATA[X1 2 ]]> 0.7414 1 0.7414 1.9049 0.1908 <![CDATA[X2 2 ]]> 4.1282 1 4.1282 10.6061 0.0063 <![CDATA[X3 2 ]]> 6.3573 1 6.3573 16.3332 0.0014 <![CDATA[X1X2]]> 2.4976 1 2.4976 6.4169 0.0250 <![CDATA[X1X3]]> 3.795 1 3.7950 9.7502 0.0081 <![CDATA[X2X3]]> 1.8336 1 1.8336 4.7109 0.0491 return 20.9498 9 2.3278 <![CDATA[F2=5.981]]> 0.0055 Remaining 5.0599 13 0.3892 - - Lack of Fit 3.5057 5 0.7011 <![CDATA[F1=3.609]]> 0.0288 error 1.5542 8 0.1943 - - sum 26.0098 22 - - -

[0075] Note: SS stands for the sum of squares of deviations, df stands for degrees of freedom, MS stands for mean square, F stands for the ratio of the mean square between groups to the mean square within groups, P stands for significant difference, - stands for the exclusion of the item, and the meanings in the following tables are the same.

[0076] From the first analysis of variance table 3, we can see that X1X2 and X2X3 are relatively significant at the 5% level, and X1X3 is extremely significant at the 1% level. Other items also have certain significance to varying degrees.

[0077] The DPS data processing system was used to analyze the experimental results and obtain the mathematical model regression equation of the initial concentration of hemicellulase, initial concentration of ethyl acetate, soaking time, and removal rate: Y = 7.73666 + 0.15956X1-0.28181X2+0.05299X3+0.22392X1 2 +0.51560X2 2 +0.63758X3 2 +0.55875X1X2+0.68875X1X3-0.47875X2X3.

[0078] At the level of α = 0.01, F1 = 3.609 in the model <F 0.01(5,8) =6.63, indicating that the experimental error is very small and all unknown factors have been taken into account in the experimental design; F2=5.981>F0.01(9,13)=4.19, indicating that the regression equation is extremely significant, the experimental speculation is extremely reliable, the prediction is accurate, and the model is established.

[0079] 3) Quadratic ANOVA

[0080] The significance test of the regression coefficient was carried out, and the insignificant items at the α=0.10 level were eliminated, and the remaining items were

[0081] The variance analysis was performed again, see Table 4. The simplified regression equation (α = 0.10) was constructed:

[0082] Y=7.73666+0.51560X2 2 +0.63758X3 2 +0.55875X1X2+0.68875X1X3-0.47875X2X3.

[0084] Table 4 Quadratic ANOVA table

[0085]

[0086]

[0087] 4) Analysis of the interaction effect between two factors

[0088] In the two-factor interactions of X1X2, X1X3, and X2X3, the effect of X1X3 was extremely significant. The effects of hemicellulase concentration (X1) and ethyl acetate soaking time (X3) on the removal rate (Y) (other factors were at zero level) are shown in Tables 5 and Figure 1 .

[0089] Table 5 Effect of hemicellulase concentration and soaking time on removal rate

[0090] <![CDATA[Horizontal X1X2]]> -1.6818 -1.3409 -1 -0.5 0 0.5 1 1.3409 1.6818 1.682 7.5919 7.3298 7.2159 7.3169 7.7367 8.4752 9.5326 10.4362 11.4881 1.341 7.9868 7.6447 7.4507 7.4343 7.7367 8.3578 9.2978 10.1214 11.0932 1 8.3817 7.9595 7.6855 7.5517 7.7367 8.2404 9.063 9.8066 10.6983 0.5 8.9608 8.4213 8.0299 7.7239 7.7367 8.0682 8.7186 9.3448 10.1192 0 9.5400 8.8830 8.3742 7.8961 7.7367 7.8961 8.3742 8.8830 9.5400 -0.5 10.1192 9.3448 8.7186 8.0682 7.7367 7.7239 8.0299 8.4213 8.9608 -1 10.6983 9.8066 9.063 8.2404 7.7367 7.5517 7.6855 7.9595 8.3817 -1.341 11.0932 10.1214 9.2978 8.3578 7.7367 7.4343 7.4507 7.6447 7.9868 -1.682 11.4881 10.4362 9.5326 8.4752 7.7367 7.3169 7.2159 7.3298 7.5919

[0091] With the increase of soaking time, the concentration of highland barley wine grains on PM 2.5 The removal rate of PM by highland barley grains increased gradually; when the concentration of hemicellulase remained unchanged, 2.5 The removal rate decreased with the increase of immersion time, and when the concentration was 0.32 mg / mL and the immersion time was 17.3 h, the maximum removal rate of 11.49% was obtained at the (-1.682, -1.682) site, and the minimum removal rate of 7.22% was obtained at the (-1, 1.682) site.

[0092] Optimization analysis and verification: The experimental data were preliminarily analyzed by DPS software. To maximize the Y value, the three factors must all be at the level of (-1.682, -1.682, -1.682), that is, the initial concentration of hemicellulase is 0.32 mg / mL, the initial concentration of ethyl acetate is 0.02 mol / L, the soaking time is 17.3 h, and the predicted removal rate is 13.17%. Under this condition, the removal rate was 12.95% through the experiment, and the actual value / model optimal value = 0.98, which is close to 1, proving that the data model is reliable and the next experiment can be carried out.

[0093] 2. Adsorption effect of different enzyme-modified highland barley grains

[0094] 1) Alkali heat treatment method

[0095] Take 20g of highland barley lees and boil them in boiling water for 20min. Put the cooked highland barley lees on a filter plate and rinse them with tap water until they are neutral. Put the rinsed highland barley lees on a filter plate to control the water, and then divide them into five equal parts. Use a conical flask to prepare five different concentrations of sodium hydroxide solutions, namely 0.1mol / L, 0.2mol / L, 0.3mol / L, 0.4mol / L, and 0.5mol / L respectively. Add five equal parts of highland barley lees to five different concentrations of sodium hydroxide solutions respectively, and rinse them in a digital constant temperature water tank. Place the mixture in a water bath for 30 minutes at 60°C; take out highland barley lees from five conical flasks and place them on a sieve, rinse them in tap water until they are neutral, and weigh them; drain the rinsed highland barley lees, spread them on a culture dish, affix label paper, and dry them in a constant temperature forced air drying oven for 24 hours at 80°C; when the highland barley lees reach a constant weight, take out the dry highland barley lees from the constant temperature forced air drying oven, weigh them on a balance, crush them, pass them through a 40-mesh sieve, weigh them again after sieving, and then put them into sealed bags for storage.

[0096] 2) Esterification coenzyme method

[0097] Take 20g of highland barley lees and boil them in boiling water for 20min, prepare 0.1mol / L ethyl acetate solution and put it in a 100mL beaker, then put the boiled highland barley lees into the solution and soak for 24h, prepare 0.1mg / mL, 0.2mg / mL, 0.3mg / mL, 0.4mg / mL and 0.5mg / mL hemicellulase solutions respectively, divide the soaked highland barley lees into equal parts and put them into the cellulase solution, bathe them in a constant temperature water bath for 30min, and set the temperature to 50℃; then adjust the temperature of the digital display constant temperature water bath to 70℃ to inactivate the enzyme for 20min; rinse with distilled water until neutral, put it in a culture dish and mark it, put it in a constant temperature blast drying oven at 80℃ and dry it for 24h, then weigh and record it; crush the dried highland barley lees through a 40-mesh sieve and record it again, then put them into sealed bags, mark them and save them.

[0098] 3) Acid coenzyme method

[0099] Take 20g of highland barley lees and boil them in boiling water for 20min, prepare 0.15mol / L citric acid solution and put it in a 100mL beaker, then soak the boiled highland barley lees in the solution for 30min; prepare 0.1mg / mL, 0.2mg / mL, 0.3mg / mL, 0.4mg / mL and 0.5mg / mL neutral protease solutions respectively, divide the soaked highland barley lees into equal parts and put them into the neutral protease solution; put them into a digital constant temperature water bath for 30min, and the temperature is set to 45℃; then adjust the temperature of the digital constant temperature water bath to 70℃ to inactivate the enzyme for 10min; rinse with distilled water until neutral, put them in a culture dish and mark them, put them in a constant temperature forced air drying oven at 80℃ and dry them for 24h, then weigh and record them; crush the dried highland barley lees through a 40-mesh sieve and record them again, then put them into sealed bags, label them and store them.

[0100] 4) Single enzyme soaking method

[0101] Take 20g of highland barley lees and boil them in boiling water for 20min, prepare 0.5mg / mL, 1mg / mL, 1.5mg / mL, 2mg / mL and 2.5mg / mL α-amylase solutions respectively, divide the boiled highland barley lees into 5 parts, add them into the α-amylase solutions respectively, heat them in a water bath at 60℃ for 30min, remove the highland barley lees after enzyme treatment and put them into 0.15mol / L KOH for enzyme inactivation treatment for 60min; rinse them with distilled water until neutral, put them in a culture dish and mark them, put them in a constant temperature forced air drying oven at 80℃ and dry them for 24h, then weigh and record them; crush the dried highland barley lees and pass them through a 40-mesh sieve, record them again, and then put them into sealed bags, mark them and store them.

[0102] 2 g of the modified Fritillaria tibetica obtained by the above different treatment methods were weighed and placed in a PM2.5 concentration of 500 ± 5 μg / m 3 In a closed box, record the readings of the air quality detector after 30 minutes, calculate the removal rate of each, repeat the experiment and take the average value. The results are as follows Figure 2 to Figure 5 shown.

[0103] The above experiments show that the four modified highland barley grains have a significant effect on PM 2.5 Comparison of adsorption: esterification coenzyme method > alkaline blanching method > acid coenzyme method > single enzyme immersion method.

[0104] 3. PM 2.5 Removal rate analysis

[0105] The optimal treatment method for obtaining highland barley lees adsorbent was selected, based on the amount of highland barley lees added, the particle size of highland barley lees, and PM 2.5 A single factor experiment was carried out on five factors: initial concentration, temperature and adsorption time.

[0106] 1) Effect of particle size of highland barley lees on PM adsorption 2.5 Impact

[0107] The modified highland barley lees were sieved through 18 mesh, 40 mesh, 60 mesh, 80 mesh and 100 mesh, and 2g of adsorbent was spread on the culture dish respectively. The culture dish was placed in a closed box for adsorption for 30 minutes at room temperature, and the removal rate was calculated. The results are as follows: Figure 6 As shown. Figure 6 It can be seen that the highland barley lees adsorbent has a good effect on PM 2.5 The removal rate increases first and then decreases with the increase of the residue particle size. The adsorption effect is best when the particle size is 60 mesh, with a removal rate of 14.19% (F=280.411, P<0.01), and the removal rate of 80 mesh is second. Therefore, the modified highland barley distiller's grains with a particle size of 60 mesh were used in the subsequent experiments.

[0108] 2) Effect of highland barley lees addition on PM adsorption 2.5 Impact

[0109] Weigh 1.0g, 2.0g, 3.0g, 4.0g, and 5.0g of modified highland barley lees respectively and add them to the culture dish. Place the culture dish in a water bath with an initial concentration of 500μg / m 3 The adsorption was carried out in a closed box for 30 minutes, and the removal rate was calculated. The results are as follows Figure 7 As shown. Figure 7 It can be seen that the modified highland barley lees has a significant effect on PM 2.5 The removal rate increased first and then decreased with the increase of the added amount. When the added amount was 3g, the removal rate reached the highest value of 16.18% (F=685.242, P<0.01). 3g had the best removal rate, and 5g had the worst removal rate.

[0110] 3)PM 2.5 Effect of initial concentration on highland barley distiller's grains

[0111] PM 2.5 The concentration was kept constant at 300 μg / m 3 400 μg / m 3 , 500 μg / m 3 , 600 μg / m 3 , 700 μg / m 3 Take 5 culture dishes and add 2g of modified highland barley wine grains respectively. Put the culture dishes into a closed box for adsorption for 30min at room temperature and calculate the removal rate. The results are as follows Figure 8 As shown. Figure 8 It can be seen that the modified highland barley lees has a significant effect on PM 2.5 The removal rate increases first and then decreases as the pollutant concentration in the closed box increases. The initial concentration is 500μg / m 3 The removal rate reached the highest value of 12.81% (F = 188.105, P < 0.01), 700 μg / m 3 The removal rate is the worst when 500 μg / m 3 As the pollution source concentration.

[0112] 4) Effect of temperature on PM adsorption 2.5 Impact

[0113] Take 5 culture dishes, weigh 2g of modified highland barley lees adsorbent, and place them at room temperature 14℃, 18℃, 22℃, 26℃, and 30℃ for adsorption for 30min, and calculate the removal rate. The results are as follows: Fig. 9 As shown. Fig. 9 It can be seen that the modified highland barley lees has a significant effect on PM 2.5 The removal rate of increased first and then decreased with the increase of temperature. The removal rate reached the highest value of 16.00% (F=89.041, P<0.01) at 26°C, followed by 22°C. As the actual ambient temperature is difficult to control, the subsequent experiments were carried out at random room temperature.

[0114] 5) Effect of adsorption time on adsorption of PM 2.5 Impact

[0115] Weigh 2g of modified highland barley lees in a petri dish and adsorb for 20min, 30min, 40min, 50min, and 60min at room temperature. Record the values ​​and calculate the removal rate. The results are as follows: Fig.10 As shown. Fig.10 It can be seen that the modified highland barley lees has a significant effect on PM 2.5The removal rate of PM2.5 increased and then decreased with time. When the adsorption time was 50 minutes, the removal rate of PM2.5 increased and then decreased. 2.5 The adsorption effect was the best, with a removal rate of 14.03% (F=142.544, P<0.01), and the removal rate was the worst at 20min and 30min.

[0116] 4. Characterization analysis and adsorption mechanism analysis

[0117] 1) Elemental analysis

[0118] The modified highland barley lees, original highland barley lees and PM adsorbed 2.5 The modified highland barley grains were subjected to elemental analysis, and the results are shown in Table 6.

[0119] Table 6 Element analysis of highland barley lees

[0120]

[0121] According to Table 6, the element changes before and after the adsorption of modified highland barley lees are mainly reflected in the increase of C and H element contents and the decrease of N and S element contents.

[0122] 2) Infrared spectroscopy analysis

[0123] The modified highland barley lees, original highland barley lees and PM adsorbed 2.5 The modified highland barley lees were analyzed by infrared spectroscopy. Fig.11 As shown, from Fig.11 It can be seen that a is the original barley lees spectrum; b is the modified barley lees spectrum; c is the adsorption of PM 2.5 The modified highland barley lees spectrum. It can be seen that at 2360.87cm -1 There is a stretching vibration of -OH at the position where the transmittance of the absorption peak increases significantly after modification and the peak vibrates, indicating that -OH participates in the modification process after the highland barley grains are treated with esterification coenzyme. The figure analysis shows that the modified highland barley grains have a certain adsorption capacity.

[0124] 3) Scanning electron microscopy analysis

[0125] The modified highland barley lees, original highland barley lees and PM adsorbed 2.5 The modified highland barley lees were analyzed by scanning electron microscope. Fig.12 As shown. Fig.12 It can be seen that the surface of the untreated original highland barley lees electron micrograph has obvious shadows, which is not conducive to the adsorption. The surface structure of the modified highland barley lees electron micrograph treated with esterified coenzyme is loose, with more wrinkles and pores, which makes it more sensitive to PM. 2.5It has a good adsorption effect. After the adsorption experiment, the surface of the modified highland barley lees is smoother, whiter, and has fewer wrinkles, proving that highland barley lees adsorb PM 2.5 Later, pollutants in the air filled the surface of the lees.

[0126] 4) Specific surface area and pore size analysis

[0127] Through the BET experiment, the specific surface area and pore volume of the modified highland barley grains prepared by the above optimal method were measured, which can intuitively illustrate that the larger pore size of the modified highland barley grains can provide adsorption sites. The results are shown in Table 7.

[0128] Table 7 Specific surface area and pore size

[0129] Test indicators Measurements <![CDATA[Specific surface area (m 2 / g)]]> 3.3460 <![CDATA[Pore volume (cm 3 / g)]]> 0.0047 Pore ​​size distribution (μm) 3.5550

[0130] 5) Adsorption mechanism analysis

[0131] The most commonly used models in adsorption equilibrium are the Langmuir and Freundlich isotherms.

[0132] At 26℃, the adsorption isotherm curve is plotted with the adsorption amount q (μg / g) versus the equilibrium concentration c (μg / m3). Fig.13 .

[0133] The models used in the present invention are the Langmuir isotherm, as shown in formula (1) and the Freundlich isotherm, as shown in formula (2):

[0134] Langmuir model: C / Qm+1 / Qmb=C / Q Formula (1);

[0135] Freundlich model: K×C 1 / n =Q formula (2).

[0136] Taking the logarithm of both sides of equation (2) can turn it into a linear form:

[0137] lgK+(1 / n)lgC=lgQ Formula (3);

[0138] Where: C is the equilibrium concentration in μg / m 3 ; Q is the equilibrium adsorption capacity, the unit is μg / g; Qm is the saturated adsorption capacity, the unit is μg / g; b is the adsorption equilibrium constant, which indicates the magnitude of the adsorption force on the adsorbate binding force; K is the Friedrich constant; n in 1 / n is the adsorption index.

[0139] The equilibrium adsorption amount calculation formula is shown in formula (4):

[0140] Q = (C0 - C) V / m Formula (4);

[0141] Where: C0 is the initial concentration, the unit is mg / m 3 ; V is the volume of the closed box, in m 3 ; m is the mass of the adsorbent, the unit is g.

[0142] Fig.13 The data were fitted with the Langmuir and Freundlich adsorption isotherms, see below Fig.14 , Fig.15 .Depend on Fig.14 , Fig.15 It can be seen that the correlation coefficient of the Freundlich equation fitting is 0.978, and the data points show good linearity. The correlation coefficient of the Langmuir equation is 0.8546. This shows that the modified highland barley lees is more in line with the law described by the Freundlich equation, and the adsorption process is a multi-layer adsorption of multiple active sites. According to the Langmuir adsorption isotherm, the modified highland barley lees adsorption of PM 2.5 The saturated adsorption capacity is 17.2400 μg / g.

[0143] Adsorption isotherm: At 25℃, PM 2.5 The initial concentration was used as a single variable for the adsorption test, and the adsorption kinetics curve was plotted with the adsorption amount versus the adsorption time. The results are shown in Fig.16 As shown. Fig.16 It can be seen that the modified highland barley lees has a significant effect on PM 2.5 The adsorption amount increases with time, and the adsorption amount first increases and then decreases. According to experimental statistics, the adsorption effect is best when the adsorption time is 50 minutes. This shows that highland barley lees has a strong ability to adsorb PM2.5. 2.5 After the adsorption time reaches 24 hours, the residual concentration reaches the national safety standard of 5μg / m 3 The adsorption isotherm parameters are shown in Table 8.

[0144] Table 8 Adsorption isotherm parameters

[0145]

[0146] Use pseudo-first-order kinetic equation and pseudo-second-order kinetic equation to Fig.16 The data are fitted, see Fig.17 , Fig.18 .Depend on Fig.17 , Fig.18 It can be seen that according to the two fitting results, the correlation coefficient of the pseudo-second-order rate equation fitting is 0.9776, which is higher than the correlation coefficient of the pseudo-first-order rate equation fitting of 0.8641, indicating that the modified highland barley wine grains have an effect on PM 2.5The adsorption law follows the pseudo-second-order kinetic model, proving that the adsorption process mainly utilizes chemical adsorption. In the process, it should be combined with the pseudo-second-order rate equation, and combined with the operation, it should also be carried out according to the key points of the pseudo-second-order kinetic equation. The pseudo-first-order kinetic equation and the pseudo-second-order kinetic equation are as follows:

[0147] The pseudo-first-order kinetic equation is lg(q e -q t ) = lgq e- k1t / 2.303 Formula (5);

[0148] The pseudo-second-order kinetic equation is t / q t =1 / (k2·q e 2 )+t / q e Formula (6).

[0149] Where: t represents time, unit is min; q refers to equilibrium adsorption capacity, unit is mg / g; q t Refers to the adsorption amount at time t, in mg / g; q e refers to the equilibrium adsorption capacity, the unit is mg / g; k1 refers to the first-order adsorption kinetic constant, the unit is min -1 ; k2 represents the secondary adsorption kinetic constant, in g·mg-1·min -1 .

[0150] The parameters of the pseudo-first-order kinetic equation and pseudo-second-order kinetic equation are shown in Table 9.

[0151] Table 9 Kinetic parameters

[0152]

[0153] The adsorption thermodynamic parameters can be calculated from the data of the effect of temperature on the adsorption equilibrium to obtain the adsorption enthalpy ΔH and the adsorption Gibbs free energy ΔG and adsorption entropy ΔS at different temperatures. The thermodynamic calculation formula is as follows:

[0154] lnKc=-ΔG0 / RT=-ΔH0 / RT+ΔS0 / R Formula (7);

[0155] K c =q / c formula (8).

[0156] Where: ΔG0 is the standard Gibbs free energy, in KJ / mol; R is the thermodynamic gas constant, with a value of 8.314 J / (mol·K); T is the thermodynamic temperature, in K; ΔH0 is the enthalpy variable of the reaction, in KJ / mol; ΔS0 is the entropy variable, in J / (mol·K); K c is the thermodynamic equilibrium constant. The relationship between temperature and adsorption amount is as follows Fig.19 and Fig. 20 The thermodynamic parameters are shown in Table 10.

[0157] Table 10 Thermodynamic parameters

[0158] T / K <![CDATA[ΔG0(KJ / mol)]]> <![CDATA[ΔH0(KJ / mol)]]> <![CDATA[ΔS0(J·mol -1 ·K -1 )]]> 14 -5.8017 0.0199 21.5657 18 -5.9005 0.0199 21.5657 22 -6.1077 0.0199 21.5657 26 -6.2584 0.0199 21.5657 30 -6.3118 0.0199 21.5657

[0159] According to Table 10, ΔH0>0, it can be known that the adsorption process is an endothermic reaction, and ΔG0<0, which proves that the adsorption process is spontaneous; Fig.18 The analysis shows that the correlation coefficient R 2 =0.8531, which proves that the adsorption process is well consistent with the thermodynamic law.

[0160] 5. Effects of different adsorbents on PM 2.5 The adsorption effect

[0161] Diatomaceous earth, bamboo charcoal, activated carbon, and macroporous adsorption resin are the most popular adsorbents on the market. Modified highland barley lees, original highland barley lees, diatomaceous earth, bamboo charcoal, activated carbon, and macroporous adsorption resin AB-8 were used to remove PM. 2.5 The adsorption effects were compared.

[0162] The specifications of the four adsorbent materials are: diatomaceous earth 325 mesh; activated carbon black granules, 60 mesh; macroporous adsorption resin AB-8 milky white translucent spherical particles, 18 mesh; modified highland barley lees powder, 60 mesh; original highland barley lees powder, 60 mesh.

[0163] Take 6 sets of culture dishes, add 2g of original highland barley lees, modified highland barley lees, diatomaceous earth, bamboo charcoal, activated carbon, and macroporous adsorption resin AB-8 to each of the 6 sets of culture dishes. Place the culture dishes at an initial concentration of 500μg / m 3 The adsorption was carried out in a closed box for 30min, 60min, 90min, 120min and 150min, and the removal rate was calculated. The results are as follows Fig.21 shown.

[0164] according to Fig.21 It can be seen that under the same conditions, the adsorption effect of modified highland barley grains is the best and is more significant than that of diatomaceous earth, activated carbon, bamboo charcoal, macroporous resin and original highland barley grains.

[0165] Table 11 Variance analysis table

[0166] Sources of variation SS df MS F P Material 1256.7162 5 251.3432 290.226 0.0001 time 148.9157 4 37.2289 42.988 0.0001 Material × Time 17.3205 20 0.8660 156.485 0.0001 error 0.3321 60 0.0055 Total variation 1423.2845 89

[0167] Table 12 Effects of different adsorbents on PM 2.5 Effect of adsorption

[0168] Material Mean α＝0.05 α＝0.01 Modified highland barley grains 15.52 a A diatomite 7.348 b B Activated carbon 7.182 c C Bamboo charcoal 6.286 d D Resin 5.638 e E Original highland barley grains 3.696 f F

[0169] According to Table 11, different materials and time have different effects on PM 2.5 The adsorption effects of the two factors were significantly different, and the interaction of the two factors significantly affected PM 2.5 As shown in Table 12, the modified highland barley lees has a significant effect on PM 2.5 The adsorption effect of the material is better than other materials, reaching a very significant level of 1%, and compared with other materials for PM 2.5 Therefore, compared with the other four adsorption materials, modified highland barley lees has a significant difference in the removal rate of PM. 2.5 A clear advantage in this area.

[0170] 6. Cycle adsorption times

[0171] The modified highland barley lees were subjected to multiple adsorption and desorption cycle tests to explore its adsorption effect. 2g of the adsorbed modified highland barley lees were placed in a culture dish, dried and adsorbed, and used repeatedly. The removal rate was calculated after each adsorption. The results are as follows: Fig. 22 shown.

[0172] Depend on Fig. 22 It can be seen that the modified highland barley lees had an impact on PM after 7 cycles. 2.5 Still has strong adsorption capacity, the 7th resource recycling has a great impact on PM 2.5 The removal rate of PM2.5 was 8.71% (F = 174.235, P < 0.01). 2.5 It still has good adsorption capacity after repeated cycles, and the overall adsorption effect is good.

[0173] Due to PM in the air 2.5 This invention mainly explores the effect of modified highland barley lees on PM 2.5 Using Tibetan highland barley lees as raw material, the effect of highland barley lees modified by ethyl acetate-assisted hemicellulase on PM was studied. 2.5 adsorption effect.

[0174] The present invention selects the modified highland barley vinasse obtained by esterification coenzyme, wherein the hemicellulase concentration is 0.4mg / mL, and the effect is the best, and the removal rate is 11.38%. Scanning electron microscope detection finds that the modified highland barley vinasse has a loose, porous, and wrinkled structure. Detected by infrared spectrometer, functional groups such as hydroxyl and carboxyl exist in the modified highland barley vinasse. Analyzed by element analyzer, the modified highland barley vinasse contains a large amount of C and H elements and a small amount of S and N elements. Detected by physical adsorption instrument, the pore volume, pore size, and specific surface area of ​​the modified highland barley vinasse provide the premise of efficient adsorption, that is, the range of adsorption sites is expanded.

[0175] Through quadratic regression orthogonal rotation combination design, the experimental data were preliminarily analyzed by DPS software, and the three levels were (-1.682, -1.682, -1.682), that is, the initial concentration of hemicellulase was 0.32 mg / mL, the initial concentration of ethyl acetate was 0.02 mol / L, and the soaking time was 17.3 h. The predicted Y max At this level, the removal rate was 12.95%, and the actual value / model optimal value = 0.98, which is close to 1, proving that the data model is reliable. 2.5 The initial concentration and adsorbent addition amount of five single factors have an impact on PM 2.5 The effects of adsorption were studied and it was found that the modified highland barley lees particle size was 60 mesh, the adsorption time was 50 min, the adsorption temperature was 26 °C, and the PM 2.5 Initial concentration 500 μg / m 3 When the addition amount is 3g, the removal rate is the best. And under the study of thermodynamics, it is proved that the modified highland barley wine grains have the best effect on PM 2.5 The adsorption effect of modified highland barley lees on PM 2.5 The effect of modified highland barley lees on PM 2.5 The effect is consistent with the thermodynamic law. After high temperature drying and 7 cycles of experiments, the removal rate of modified highland barley lees is equivalent and can be reused many times.

[0176] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0177] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A modified highland barley lees, characterized in that: The modified highland barley vinasse is prepared by the following method: The steamed highland barley lees are soaked in an ethyl acetate solution for 17 to 31 hours, a hemicellulase solution is added, and a water bath reaction is performed at 50 to 55 degrees Celsius for 28 to 30 minutes to increase the content of hydroxyl and carboxyl groups in the highland barley lees, and the enzyme is inactivated at 70 to 75 degrees Celsius for 18 to 20 minutes to obtain the enzyme-inactivated highland barley lees; The enzyme-inactivated highland barley lees are rinsed to neutrality, dried, and crushed to obtain the modified highland barley lees; The modified highland barley lees is used for PM 2.5 Adsorption; The concentration of the ethyl acetate solution is 0.02 mol / L to 0.18 mol / L; The concentration of the hemicellulase solution is 0.32 g / L to 0.48 g / L.

2. The modified highland barley lees according to claim 1, characterized in that: The particle size of the modified highland barley lees is 40-80 meshes.

3. The modified highland barley lees according to claim 1, characterized in that: The mass volume ratio of the highland barley grains to the hemicellulase solution is 10kg:50L-55L.

4. The modified highland barley lees according to claim 1, characterized in that: The steaming time is 18 to 20 minutes.

5. An air purifier, characterized in that: The air purifier is composed of the modified highland barley lees as described in any one of claims 1 to 4 as the only effective ingredient.

6. An air purifier according to claim 5 for use in the preparation of a method for removing PM from the air 2.5 Application in air purifiers.

7. A PM 2.5 The removal method is characterized in that The modified highland barley lees according to any one of claims 1 to 4 is placed in a medium containing PM 2.5 In the gas, the modified highland barley lees are used to treat PM 2.5 Adsorption to remove PM from the gas 2.5 .

8. The PM according to claim 7 2.5 The removal method is characterized in that The quality of the modified highland barley lees and PM 2.5 The ratio of the adsorption amount is 3g:79μg~81μg.

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