Method for simply and conveniently measuring absolute contents of organic acids and phenols in biomass dry distillation acid

Abstract

The invention discloses a method for simply and conveniently measuring absolute contents of organic acids and phenols in biomass dry distillation acid. The method comprises the following steps: step S1, preparing an alkali solution; s2, diluting biomass dry distillation acid; s3, taking the diluted biomass dry distillation acid stock solution, and adding acetic acid into the diluted biomass dry distillation acid stock solution; s4, neutralizing and titrating; s5, finding the gram number of the Y-axis standby alkaline solution corresponding to the nearest point with the pH value of 7.25 on the Y axis of the curve; s6, establishing a linear regression equation; s7, calculating the percentage of total acid; s8, taking the diluted biomass dry distillation acid stock solution, and adding phenolic substances into the diluted biomass dry distillation acid stock solution; step S9, carrying out neutralization titration; s10, drawing a curve by taking the gram number of the standby alkaline solution as an X axis and the pH value as a Y axis; s11, establishing a linear regression equation; and S12, calculating the percentage of total phenols. The method is simple and practical, does not need professional training, and is convenient to use and high in efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of effective component determination and quality evaluation of natural biomass dry distillation acid, and in particular to a method for simply determining the absolute contents of organic acids and phenols in biomass dry distillation acid. Background Art

[0002] Agricultural waste can be converted into materials with multiple values ​​through thermochemical conversion of energy, which plays an important role in the development of sustainable economic and ecological material cycles. For example, it is estimated that 2% of agricultural waste is converted into biochar, which is prepared by fast and slow pyrolysis of biomass. The by-product obtained is called pyroligneous acid (PA). The characteristics and properties of PA are affected by the type of raw materials and production technology. PA is a complex mixture of polar and non-polar chemical components, of which acetic acid and phenols are the main components. PA has extremely wide applications: 1) antiviral activity; 2) possible use as a food or feed additive to prevent lipid peroxidation, and also in veterinary anti-inflammatory products; 3) air disinfectant and deodorant; 4) wood preservation; 5) health food and pharmaceutical products, enhancing calcium and magnesium absorption and blood circulation. It can inhibit allergic reactions, especially type I allergic reactions after oral administration. The solution is suitable for preventing allergic rhinitis, hay fever, allergic conjunctivitis, atopic dermatitis, allergic asthma, urticaria and food allergies; 6) Food additives and preservatives. The U.S. Food and Drug Administration (FDA) allows the use of pyroligneous acid to season and preserve foods such as ham, bacon, sausage, fish and cheese; 7) Plant growth regulators; 8) Soil conditioners; 9) Organic fertilizers; 10) Agricultural pesticides; 11) Agricultural fungicides; 12) Herbicides; 13) Calcium supplements for humans, farmed animals and crops; 14) Food acidity regulators.

[0003] At present, due to the increasingly stringent environmental protection requirements in my country, biochar products, especially bamboo charcoal produced by further utilizing bamboo processing waste, are in short supply in the market, but a large amount of excess bamboo vinegar cannot be used legally, resulting in a negative price of 400 yuan / ton, and it is treated as hazardous waste. Although PA only refers to bamboo vinegar and wood vinegar that can be used as inputs for organic production, it also needs to be certified organically, and the premise of organic certification is to register pesticides and organic fertilizers first. Although there are some test exemptions for the registration of this new biopesticide, it still takes 3 years and requires expensive registration fees. The risk of successful registration is very high, and it also depends on the various complex components and quality of PA that cannot be scientifically evaluated. For example, what is the chemical structure of the active ingredient and what is the content of natural acetic acid? How to scientifically determine its composition and content? Impurity chemical composition and content? All of the above questions require absolute content rather than relative content determined by GCMS, because relative content has almost no commercial and market value, although more than 10,000 SCI articles have been published in the past 10 years, which only provide the relative content of chemical components in PA. We used Web of Science to search for relevant articles published in the past 10 years, and the Topic "pyroligneous acid or woodvinegar or bamboo vinegar or straw vinegar" showed 21,649 results from All Databases, (including 15,161 articles in the past 5 years (2018.01-2023.11)). Many articles used GCMS to determine the relative content of each chemical component in PA, and there were few tests on the absolute content of acids and phenolic substances. Therefore, it is almost meaningless to study the relative content of bioactive substances in various uses of PA, because the dosage is closely related to the active effect, and without absolute content test data, it is impossible to determine the actual dosage of the active ingredients in PA.

[0004] Agricultural and forestry wastes have been used for 3 million years, and the application of these biomasses to biochar has been more than 3,300 years. The civilian application of its byproduct PA has also exceeded 500 years. Although the research in the past century has shown that PA has a wide range of uses, it has been limited to private use and has not yet been legally used by the public. The main reason is that there is no simple, practical and cheap scientific method for determining the absolute content of active ingredients. After more than 20 years of exploration and experience, the present invention has designed a set of convenient methods for testing the absolute content of active ingredients in PA, including organic acids and phenols, without the need for professional training. Relative content has almost no reference significance in commercial transactions and registration and licensing processes. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a method for simply determining the absolute content of organic acids and phenols in biomass dry distillation acid, which solves the problem of the most basic cornerstone of the absolute content determination technology of organic acids and phenols in biomass dry distillation acid. The method can be used not only in factories but also in laboratories to determine the absolute content of effective components in biomass dry distillation acid; and can also be used for designing and producing related determination instruments and equipment.

[0006] In order to achieve the above object, the present invention is achieved through the following technical solutions:

[0007] A method for simply determining the absolute content of organic acids and phenols in biomass dry distillation acid, characterized in that it comprises the following steps:

[0008] Step S1: preparing an alkali solution with a concentration between 5% and 10%, wherein the concentration of the alkali solution is set to p, and the molecular weight of the alkali is set to q, and then obtaining a standby alkali solution;

[0009] Step S2: diluting the biomass dry distillation acid stock solution with distilled water to n times, wherein n is a natural number between 5 and 20; Step S3: taking 100 g of the diluted biomass dry distillation acid stock solution and pouring it into 5 200 ml beakers respectively, and adding 0 g, 0.3 g, 0.6 g, 0.9 g, and 1.2 g of pure acetic acid to the first to fifth beakers respectively for standby use;

[0010] Step S4: neutralize and titrate with the reserve alkali solution, add 0.2 g of the reserve alkali solution to the five beakers each time, measure and record the pH value and the number of grams of the reserve alkali solution added under a stirring speed of 120 r / min, and continue to add until the pH value is ≥12.0;

[0011] Step S5: draw a curve with the grams of the standby alkali solution as the X-axis and the pH value as the Y-axis, and find the grams of the standby alkali solution on the Y-axis corresponding to the nearest point of pH=7.25 on the Y-axis of the curve, which is the grams of alkali consumed;

[0012] Step S6: A linear regression equation is established based on the new X-axis as the increased grams of pure acetic acid including 0g, 0.3g, 0.6g, 0.9g, and 1.2g and the corresponding grams of the reserved alkaline solution consumed as the new Y-axis, and the equation is set as Y1=a1X1+b 1；

[0013] Step S7: Calculation of total acid percentage: Let X1=0, Y1 value be the standby alkali solution consumed by the dilution of the biomass dry distillation acid stock solution, and the molecular weight of the organic acid be set to c, then the absolute content of the organic acid in the biomass dry distillation acid stock solution is: n×Y1 / q×c×p×100%;

[0014] Step S8: taking 100 g of the diluted biomass dry distillation acid stock solution and pouring it into 5 new 200 ml beakers respectively, adding 0 g, 0.31 g, 0.62 g, 0.93 g, and 1.24 g of phenolic substances into the first to fifth beakers respectively, and then setting aside;

[0015] Step S9: neutralize and titrate with the reserve alkali solution, add 0.2 g of the reserve alkali solution to the five beakers each time, measure and record the pH value and the number of grams of the reserve alkali solution added at a stirring speed of 120 r / min, and continue to add until the pH value is ≥12.0;

[0016] Step S10: draw a curve with the grams of the reserve alkali solution as the X-axis and the pH value as the Y-axis, find two points on the Y-axis of the curve where pH=7.25 and pH=11.15, and the difference between the grams of the reserve alkali solution consumed at the two points on the Y-axis is the grams of the reserve alkali solution consumed by the reaction of the phenolic substance;

[0017] Step S11: Establish a linear regression equation based on the new X-axis, which is the grams of the added phenolic substances, including 0g, 0.31g, 0.62g, 0.93g, and 1.24g, and the Y-axis, which is the grams of the spare alkaline solution consumed by the reaction of the phenolic substances, and the equation is set as Y2=a2X2+b2;

[0018] Step S12: Calculation of total phenol percentage: Let X2=0, Y2 value be the grams of alkali consumed by phenolic substances in the diluted biomass dry distillation acid stock solution, the molecular weight of phenol is set to d, and the absolute content of phenol in the biomass dry distillation acid stock solution is: n×Y2 / q×d×p×100%.

[0019] As a preferred method, the simplified steps are as follows: dilute the biomass dry distillation acid stock solution to n times, take 100g of the dilution solution, titrate with a 10% alkali solution, draw a curve with the grams of 10% alkali as the X-axis and the pH value as the Y-axis, find the X value of pH = 7.25 on the X-axis of the curve a Value and pH = 11.15 X b The two closest points of the value correspond to the two points Y on the Y axis a and Y b , where Y a Y is the number of grams of 10% alkaline solution consumed by biomass dry distillation acid stock solution, b Y is the sum of grams of 10% alkaline solution consumed by adding phenolic substances to the biomass dry distillation acid stock solution. b -Y a is the number of grams of 10% alkaline solution consumed by the reaction of phenolic substances. The absolute contents of organic acids and phenols in the biomass dry distillation acid stock solution are calculated based on the molecular weight and the dilution multiple. The absolute content of organic acids in the biomass dry distillation acid stock solution is calculated as Y a×10%×c / q×n×100%, calculate the absolute content of phenol in the biomass dry distillation acid stock solution as (Y b -Y a )×10%×d / q×n×100%.

[0020] Preferably, if the organic acid is acetic acid, the absolute content of acetic acid in the biomass dry distillation acid stock solution is Y a ×10%×60 / q×n×100%,

[0021] Preferably, if the phenol is guaiacol, the absolute content of guaiacol in the biomass dry distillation acid stock solution is (Y b -Y a )×10%×124 / q×n×100%.

[0022] As a preferred method, the method for determining and calculating the absolute content of other substances in the biomass dry distillation acid stock solution is as follows: according to the relative content determined by the recognized mass spectrometry GCMS method, the percentage of all phenolic substances is normalized, and then the weighted average molecular weight m of the phenolic substances is calculated, wherein there are n hydroxyl groups, the weighted average molecular weight m of hydroquinone is m=110 / 2=55, and the weighted average molecular weight m of hydroquinone is m=126 / 3=42, and the molecular weight is corrected by its molecular weight / n as the correction molecular weight, and the total phenolic content after correction is: the absolute content of phenols before correction / d×m., the relative content of other substances is determined by combining the GCMS method, and the other substances include aldehydes, ketones, alcohols, and esters. The absolute content of the above other substances is calculated according to the same proportion. If the absolute content of total phenols is 6%, the sum of the relative contents of various phenolic substances in GCMS is 60%, and the relative content of ethyl acetate is 2%, then the absolute content of ethyl acetate is: 6% / 60%×2%=0.2%.

[0023] Preferably, the biomass dry distillation acid includes any one of bamboo vinegar, wood vinegar or straw vinegar, and also includes raw liquid, liquid collected after distillation or activated carbon filtration, and also includes bamboo tar, wood tar or straw tar.

[0024] Preferably, the alkaline solution is KOH or NaOH.

[0025] The beneficial effects of the present invention are as follows: the method of the present invention is simple and practical, and the absolute content of the effective ingredient can be determined at low cost. The present invention does not require professional training, is easy to use, and has high efficiency. The present invention provides the most critical scientific basis, rules and calculation methods for establishing a practical and internationally applicable commercial technical standard for the real commercial application of PA and the sustainable development of the biochar industry. The ideas and methods of the present invention may also be extended to the determination of the absolute content of many other naturally extracted compounds, such as natural products that require a multi-component mixture of organic acids and phenolic substances; the present invention is not only used in factories but also in laboratories to determine the absolute content of effective ingredients in biomass dry distillation acid, and can also be used to design and produce related measurement instruments and equipment, solving the problem of the most basic cornerstone of the absolute content determination technology of organic acids and phenolic substances in biomass dry distillation acid. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The graph of the pH value change of biomass dry distillation acid solution when different weights of 10% NaOH solution are added to solutions with different acetic acid concentrations;

[0027] Figure 2 This is a graph showing the pH change of biomass dry distillation acid when NaOH solution is added to aqueous guaiacol solutions of different concentrations;

[0028] Figure 3 The graph of the change in pH value of biomass dry distillation acid when 10% NaOH solution is added to 100g of a mixture of 0.30-0.64% acetic acid and 0.31% guaiacol;

[0029] Figure 4 The graph of the change of pH value of biomass dry distillation acid when 10% NaOH solution is added to 100g of a mixture of 0.9-2.1% acetic acid and 0.93% guaiacol;

[0030] Figure 5 The graph of the change in pH value of biomass dry distillation acid when 10% NaOH solution is added to a mixture of 100g guaiacol concentration (0.31-1.55%) and 0.6% acetic acid;

[0031] Figure 6 The pH difference of biomass dry distillation acid when other substances (ethyl acetate + ethanol + acetone in equal proportions) are added to a mixed aqueous solution of 0.6% acetic acid and 0.63% guaiacol, and then 10% NaOH solution is added;

[0032] Figure 7 It is a graph showing the change in pH value of bamboo vinegar when different weights of 10% NaOH solution are added to a mixed aqueous solution of acetic acid and guaiacol;

[0033] Figure 8The graph of the pH value of bamboo vinegar when different weights of 10% NaOH solution are added to the mixed aqueous solution of guaiacol;

[0034] Fig. 9 This is the GCMS chart of bamboo vinegar;

[0035] Fig.10 The graph of pH value change when adding different weights of 10% NaOH solution into wood vinegar;

[0036] Fig.11 The graph is a graph showing the change in pH when guaiacol and different weights of 10% NaOH solution are added to wood vinegar;

[0037] Fig.12 The graph of pH value changes when adding different weights of 10% NaOH solution into straw vinegar;

[0038] Fig.13 The graph shows the pH change when guaiacol and different weights of 10% NaOH solution are added to the straw vinegar. DETAILED DESCRIPTION

[0039] The technical solution of the present invention is further described below:

[0040] Embodiment 1:

[0041] 1) Prepare 10% NaOH aqueous solution for later use;

[0042] 2) preparing 0.3-2.1% acetic acid aqueous solution for later use;

[0043] 3) Pour 100 g of 0.3%, 0.6%, 0.9%, 1.2%, 1.5%, 1.8%, and 2.1% acetic acid aqueous solutions into 200 ml beakers respectively;

[0044] 4) Use 10% NaOH aqueous solution for neutralization titration, add 0.2g NaOH aqueous solution each time, measure and record pH value and the number of grams of NaOH aqueous solution added under stirring speed of 120r / min, and add until pH value ≥12.0. Repeat the above test 3 times, and calculate the mean value and variance value by variance analysis;

[0045] 5) Draw a curve with the grams of NaOH aqueous solution as the X-axis and the pH value as the Y-axis, such as Figure 1 As shown, the X-axis represents the number of times 10% NaOH solution was added, 0.2 g was added each time, and the Y-axis represents the pH value. The mean and variance of the three repeated data were calculated by Tukey's variance analysis at the p < 0.05 level. The grams of NaOH on the Y-axis corresponding to the nearest point of pH = 7.25 or 11.15 on the Y-axis of the curve is the grams of NaOH consumed;

[0046] 6) A linear regression equation is established based on the new X-axis as the grams of acetic acid added (0g, 0.3g, 0.6g, 0.9g, 1.2g, 1.5g, 1.8g) and the Y-axis corresponding to the grams of NaOH consumed, Y1 = a1X1 + b 1；

[0047] 7) Calculation of total acid (in terms of acetic acid) percentage: Let X1 = 0, and Y1 be the grams of NaOH consumed by the biomass dry distillation acid dilution solution. Then the organic acid percentage concentration of the biomass dry distillation acid stock solution is: n×Y1 / 40×60×100%

[0048] Figure 1 It can be seen that the pH value changes when adding NaOH solution to aqueous acetic acid solutions of different concentrations. When the acetic acid concentration is 0.3-2.1% aqueous solution, the pH values ​​of all 7 curves at the reaction end point are between 11.0-11.5.

[0049] Table 1 Calculation of the absolute content of acetic acid at different concentrations by the method of the present invention

[0050]

[0051]

[0052] Table 1

[0053] The calculation method in Table 1 is to assume that the 0.3% acetic acid aqueous solution is the unknown liquid, the 0.6% acetic acid aqueous solution is the unknown liquid with 0.3g of acetic acid added, and so on. Therefore, the first five samples are: the added acetic acid samples are: 0.0g, 0.3g, 0.6g, 0.9g, 1.2g, with these five points as the X-axis, and the points near pH 7.25 or 11.15 are found ( Figure 1 ) corresponds to the number of grams of NaOH consumed as the Y-axis, and a linear regression equation is established, as shown in Table 1. It can be seen that in the case of only organic acids, the error produced by selecting a point near pH 11.15 is smaller. This special case is suitable for determining the absolute content of phenol-free biomass dry distillation acid, such as biomass dry distillation acid after distillation or activated carbon filtration.

[0054] A simple algorithm, using only Figure 1 From the first curve, it can be seen that the point pH11.45±0.02 near pH 11.15 corresponds to 0.20g of NaOH consumption, which is equivalent to 0.3g of acetic acid, and the error with the actual value is zero; the point pH7.25 is pH 6.21±0.07, that is, 0.27g, and the error with the actual value is -10%; therefore, the data error obtained by selecting the point pH11.15 is the smallest.

[0055] The scope of this embodiment refers to biomass dry distillation acid containing only organic acid but no tar, such as biomass dry distillation acid treated by technical means such as distillation and activated carbon filtration.

[0056] Embodiment 2:

[0057] 1) Prepare 10% NaOH aqueous solution for later use;

[0058] 2) preparing a 0.31-1.55% guaiacol aqueous solution for later use;

[0059] 3) Pour 100 g of 0.31%, 0.62%, 0.93%, 1.24%, and 1.55% guaiacol aqueous solutions into 200 ml beakers respectively;

[0060] 4) Use 10% NaOH aqueous solution for neutralization titration, add 0.2g NaOH aqueous solution each time, measure and record pH value and the number of grams of NaOH aqueous solution added under stirring speed of 120r / min, until pH value ≥12.0; repeat the above test 3 times, and calculate the mean value and variance value by variance analysis;

[0061] 5) Draw a curve with the grams of NaOH aqueous solution as the X-axis and the pH value as the Y-axis (see Figure 2 ), find the nearest point of 7.25 or 11.15 on the Y axis of the curve, and the corresponding Y axis NaOH grams are the grams of NaOH consumed;

[0062] 6) Establish a linear regression equation based on the new X-axis representing the grams of guaiacol added (0 g, 0.31 g, 0.62 g, 0.93 g, 1.24 g) and the Y-axis corresponding to the grams of NaOH consumed, Y1=a2X2+b2;

[0063] 7) Draw a curve with the grams of NaOH as the X-axis and the pH value as the Y-axis, find the point of pH=7.25 and the point of pH=11.15 on the Y-axis of the curve, and the difference between the grams of NaOH at the two points on the Y-axis is the grams of NaOH consumed by the guaiacol reaction;

[0064] 8) A linear regression equation was established based on the difference between the number of grams of guaiacol added on the X-axis (0 g, 0.31 g, 0.62 g, 0.93 g, and 1.24 g after purification) and the NaOH consumed on the Y-axis, Y2=a2X2+b2;

[0065] 9) Calculation of total phenol percentage: Let X2=0, and Y2 be the grams of NaOH consumed by the biomass dry distillation acid dilution solution. Then the percentage concentration of phenol (in terms of guaiacol) in the biomass dry distillation acid sample is: n×Y2 / 40×124×100%.

[0066] The above is the case of biomass dry distillation acid with only phenols and no organic acids, such as bamboo tar, wood tar and straw tar. The following are the test results and calculation results (see Figure 2 and Table 2):

[0067] Figure 2 The pH value changes when 10% NaOH solution is added to 100g guaiacol solution with different concentrations (0.31-1.24%); the X-axis represents the number of times 10% NaOH solution is added, 0.2g is added each time, and the Y-axis represents the pH value. The variance of the mean is calculated by Tukey's at the p<0.05 level for 3 repeated data.

[0068] curve Figure 2 With similar Figure 1 The characteristic is that the pH value near pH 5.0 before the titration suddenly increases to pH 8.0, and then increases slowly. This means that there are only phenols in PA but no organic acids (or very little organic acids). Therefore, when calculating the phenol content, the pH value near pH 11.15 can be directly used, and the error of the calculation result is 0.

[0069] Table 2 shows the regression equations when 10% NaOH solution was added to 100g guaiacol solution at different concentrations and pH was 11.15.

[0070]

[0071] Table 2

[0072] The scope of this embodiment refers to biomass dry distillation acid without organic acid and only containing tar, such as biomass tar.

[0073] Example 3

[0074] 1) Prepare 10% NaOH aqueous solution for later use;

[0075] 2) Prepare 5 samples including 0.30% acetic acid + 0.31% guaiacol, 0.39% acetic acid + 0.31% guaiacol, 0.48% acetic acid + 0.31% guaiacol, 0.57% acetic acid + 0.31% guaiacol, and 64% acetic acid + 0.31% guaiacol, and put 100 g of each into 5 200 ml beakers respectively;

[0076] 3) Use 10% NaOH aqueous solution for neutralization titration, add 0.2g NaOH aqueous solution each time, measure and record the pH value and the number of grams of NaOH aqueous solution added under stirring speed of 120r / min, and add until the pH value is ≥12.0;

[0077] 4) Draw a curve with the grams of NaOH aqueous solution as the X-axis and the pH value as the Y-axis, such as Figure 3As shown, the grams of NaOH on the Y axis of the curve corresponding to the nearest point of pH = 7.25 or 11.15 is the grams of NaOH consumed;

[0078] 5) A linear regression equation is established based on the new X-axis for the grams of acetic acid added (0 g, 0.09 g, 0.18 g, 0.27 g, 0.36 g) and the Y-axis for the grams of NaOH consumed, Y1 = a1X1 + b 1；

[0079] 6) Calculation of total acid percentage: Let X1=0, and Y1 be the grams of NaOH consumed by the biomass dry distillation acid dilution solution. Then the organic acid percentage concentration of the biomass dry distillation acid stock solution is: n×Y1 / 40×60×100%;

[0080] Table 3 Calculation of organic acid content (in terms of acetic acid) using a mixture of 0.30-0.64% acetic acid + 0.31% guaiacol.

[0081]

[0082] Table 3

[0083] As can be seen from Table 3, the measured acetic acid content is 0.1960*60 / 40=0.294%, which is only -2.00% different from the actual value of 0.3%.

[0084] Example 4

[0085] 1) Prepare 10% NaOH aqueous solution for later use;

[0086] 2) Prepare 5 samples including 0.9% acetic acid + 0.93% guaiacol, 1.2% acetic acid + 0.93% guaiacol, 1.5% acetic acid + 0.93% guaiacol, 1.8% acetic acid + 0.93% guaiacol, and 2.1% acetic acid + 0.93% guaiacol, and put 100 g of each into 5 200 ml beakers respectively;

[0087] 3) Use 10% NaOH aqueous solution for neutralization titration, add 0.2g NaOH aqueous solution each time, measure and record the pH value and the number of grams of NaOH aqueous solution added under stirring speed of 120r / min, and add until the pH value is ≥12.0;

[0088] 4) Draw a curve with the grams of NaOH aqueous solution as the X-axis and the pH value as the Y-axis, such as Figure 4 As shown, the grams of NaOH on the Y axis corresponding to the nearest point of pH=7.25 on the Y axis of the curve is the grams of NaOH consumed;

[0089] 5) A linear regression equation is established based on the new X-axis for the grams of acetic acid added (0g, 0.3g, 0.6g, 0.9g, 1.2g) and the Y-axis for the grams of NaOH consumed, Y1 = a1X1 + b 1；

[0090] 6) Calculation of total acid percentage: Let X1=0, and Y1 be the grams of NaOH consumed by the biomass dry distillation acid dilution solution. Then the organic acid percentage concentration of the biomass dry distillation acid stock solution is: n×Y1 / 40×60×100%;

[0091] Figure 4 The graph shows the change in pH when 10% NaOH solution is added to 100g of a mixture of 0.9-2.1% acetic acid + 0.93% guaiacol. The mean and variance of three replicate data were calculated by Tukey's ANOVA at the p<0.05 level.

[0092] Table 4 shows the regression equation for 0.90-2.10% acid + 0.93% guaiacol.

[0093]

[0094] Table 4

[0095] The mixed aqueous solutions of 0.90-2.10% acetic acid + 0.93% guaiacol all represent the situation where the acid content changes while the phenolic substances remain unchanged, and the error produced by the measurement results is only -0.33%, as can be seen from Table 4.

[0096] Example 5

[0097] 1) Prepare 10% NaOH aqueous solution for later use;

[0098] 2) Prepare 5 samples including 0.60% acetic acid + 0.31% guaiacol, 0.6% acetic acid + 0.62% guaiacol, 0.6% acetic acid + 0.93% guaiacol, 0.6% acetic acid + 1.24% guaiacol, and 0.6% acetic acid + 1.55% guaiacol, and put 100 g of each into 5 200 ml beakers respectively;

[0099] 3) Use 10% NaOH aqueous solution for neutralization titration, add 0.2g NaOH aqueous solution each time, measure and record the pH value and the number of grams of NaOH aqueous solution added under stirring speed of 120r / min, and add until the pH value is ≥12.0;

[0100] 4) Draw a curve with the grams of NaOH aqueous solution as the X-axis and the pH value as the Y-axis, such as Figure 5 As shown, the grams of NaOH on the Y axis of the curve corresponding to the nearest point of pH = 7.25 and 11.15 is the grams of NaOH consumed;

[0101] 5) A linear regression equation was established based on the new X-axis for the increased grams of guaiacol (0 g, 0.31 g, 0.62 g, 0.93 g, 1.24 g) and the Y-axis for the corresponding grams of NaOH consumed Y2-Y1 (the difference between the total consumption of acid phenol and the consumption of acid), Y2=a2X2+b 2；

[0102] 6) Calculation of total phenol percentage: Let X2 = 0, and Y2 be the grams of NaOH consumed by the biomass dry distillation acid dilution solution. Then the percentage concentration of phenol (in terms of guaiacol) in the biomass dry distillation acid sample is: n×Y2 / 40×124×100%;

[0103] Figure 5 The graph is the change of pH value when 10% NaOH solution is added to the mixture of 100g guaiacol concentration (0.31-1.55%) and 0.6% acetic acid; the mean and variance of 3 replicates were calculated by Tukey's ANOVA at p<0.05 level. Table 5 is the regression equation of 0.90-2.10% acetic acid + 0.93% guaiacol.

[0104]

[0105] Table 5

[0106] As shown in Table 5, the mixed aqueous solution of 0.6% acetic acid + 0.31-1.55% guaiacol all indicates that the acid content does not change but the phenolic substances change, and the error of the measurement result is only 4.00%.

[0107] Figure 6 It is: a mixed aqueous solution of 0.6% acetic acid + 0.63% guaiacol, to which 0.0g, 0.2g, 0.4g, 0.6g, and 0.8g of other substances (ethyl acetate + ethanol + acetone in equal proportions) are added respectively, and then 5% NaOH aqueous solution is used, 0.2g of alkaline aqueous solution is added each time, the pH value is measured, and then the pH value without adding other substances is subtracted from the pH value with adding other substances, which is △pH.

[0108] The variance analysis of ΔpH shows that the ΔpH of all acid-phenol aqueous solutions with 0.2-0.8g of other substances added to them, when an equal amount of NaOH is added, is not significantly different from that of the acid-phenol aqueous solutions without other substances, indicating that the pH value of NaOH titration has no effect when the content of other substances is 0.2-0.8%. This test shows that the "other substances" in the assumption described in the text have no significant effect on the measurement results. The above Examples 1-5 use various types of simulated biomass dry distillates for testing, which also shows that phenolic substances have a significant effect on the determination of organic acid content, and organic acids have a significant effect on the determination of phenolic substance content, but the effects are equal. Therefore, the regression method can eliminate this effect. It can be seen from the error calculation of Tables 1-5 that the error between the measured values ​​and the actual values ​​is <5%. The following Examples 6-8 are actual measurements of real biomass dry distillates including bamboo vinegar, wood vinegar and straw vinegar.

[0109] Table 6 shows the error analysis at different titration endpoints.

[0110]

[0111]

[0112] Table 6

[0113] The method for calculating the error is as follows: measure the amount of NaOH consumed by the solution and then use the formula (measured value - actual value) / actual value * 100%. A negative value means that the measured value is lower than the actual value, and a positive value means that the measured value is higher than the actual value. Therefore, the pH value closest to 7.25 should be selected as the first endpoint to calculate the amount of NaOH used for the total acid inflection point value (m1). Similarly, the pH value closest to 11.15 should be selected as the second endpoint to determine the amount of NaOH used for total phenols and acids (m2). Finally, the amount of NaOH consumed for total phenols is m2-m1.

[0114] As can be seen from Table 6, when the endpoint of total acid is selected as pH 7.00-7.50 and the endpoint of total phenol is selected as pH 11.00-11.30, the error is minimal, and the errors are 0% and ±4% respectively. Therefore, the present invention selects the endpoints of calculating acid and phenol as the nearest points of pH 7.25 and 11.15 as the endpoint values.

[0115] Example 6

[0116] 1) Prepare 10% NaOH aqueous solution for later use;

[0117] 2) Dilute the bamboo vinegar with distilled water to n times, n = 20;

[0118] 3) Take 100g of the diluted bamboo vinegar and pour it into 200ml beakers respectively, for a total of 5 beakers, and add 0g, 0.3g, 0.6g, 0.9g, and 1.2g of acetic acid to the 1st to 5th beakers respectively for standby use;

[0119] 4) Use 10% NaOH aqueous solution for neutralization titration, add 0.2g NaOH aqueous solution each time, measure and record the pH value and the number of grams of NaOH aqueous solution added under stirring speed of 120r / min, and add until the pH value is ≥12.0;

[0120] 5) Draw a curve with the grams of NaOH aqueous solution as the X-axis and the pH value as the Y-axis. The grams of NaOH on the Y-axis corresponding to the point where pH = 7.25 is the grams of NaOH consumed.

[0121] 6) Establish a linear regression equation based on the new X-axis representing the grams of acetic acid added (0 g, 0.3 g, 0.6 g, 0.9 g, 1.2 g) and the Y-axis representing the grams of NaOH consumed, Y1=a1X1+b1;

[0122] 7) Calculation of total acid percentage: Let X1 = 0, and Y1 be the grams of NaOH consumed by the biomass dry distillation acid dilution solution. Then the organic acid percentage concentration of the biomass dry distillation acid stock solution is: 20×Y1 / 40×60×100%;

[0123] 8) In addition, 100 g of the diluted bamboo vinegar was poured into 200 ml beakers, a total of 5 beakers, and 0 g, 0.31 g, 0.62 g, 0.93 g, and 1.24 g of guaiacol were added to the 1st to 5th beakers respectively for standby use;

[0124] 9) Use 10% NaOH aqueous solution for neutralization titration, add 0.2g NaOH aqueous solution each time, measure and record the pH value and the number of grams of NaOH aqueous solution added under stirring speed of 120r / min, and add until the pH value is ≥12.0;

[0125] 10) Draw a curve with the grams of NaOH as the X-axis and the pH value as the Y-axis, such as Figure 7 As shown, find the point of pH=7.25 and the point of pH=11.15 on the Y axis of the curve. The difference in the grams of NaOH corresponding to the two points on the Y axis is the grams of NaOH consumed by the guaiacol reaction.

[0126] 11) A linear regression equation was established based on the difference between the number of grams of guaiacol added on the X-axis (0 g, 0.31 g, 0.62 g, 0.93 g, and 1.24 g after purification) and the NaOH consumed on the Y-axis, Y2=a2X2+b2;

[0127] 12) Calculation of total phenol percentage: Let X2 = 0, and Y2 be the grams of NaOH consumed by the biomass dry distillation acid dilution solution. Then the percentage concentration of phenol (in terms of guaiacol) in the biomass dry distillation acid sample is: 20 × Y2 / 40 × 124 × 100%;

[0128] Figure 7 It is a graph showing the change in pH value of bamboo vinegar when different weights of 10% NaOH solution are added to a mixed aqueous solution of acetic acid and guaiacol; Figure 7 Taking bamboo vinegar (BV) as an example, the method of the present invention is used to determine the content of organic acid (OA) (in terms of acetic acid (AA)), 100g BV20+0.0gAA, that is, dilute BV to 20 times with distilled water, take 100g of the diluted BV liquid, and add 0.0gAA. The X-axis represents the number of times 10% NaOH solution is added, 0.2g is added each time, and the Y-axis represents the pH value. The mean and variance of 3 repeated data are calculated by Tukey's at the p<0.05 level.

[0129] Figure 8 Taking BV as an example, the content of phenolic substances (calculated as guaiacol) was determined. 100g BV20+0.0gAA, that is, BV was diluted to 20 times with distilled water, and then 100g of the diluted BV solution was taken and 0.0gAA was added. The X-axis represents the number of times 10% NaOH solution was added, 0.2g was added each time, and the Y-axis represents the pH value. The mean and variance of the three repeated data were calculated by Tukey's at the p<0.05 level.

[0130] Table 7 Calculation of the absolute content of organic acids and phenols in bamboo vinegar (in acetic acid) and phenol content (in guaiacol)

[0131]

[0132]

[0133] Table 7

[0134] As shown in Table 7, there is still a certain difference between the regression method and the simplified determination method, with the maximum difference reaching nearly 11%. It can be seen that the priority use of the regression method can improve the accuracy of the data.

[0135] Figure 8 The GCMS chart of bamboo vinegar shows the relative contents of the substances as shown in the following table:

[0136] Table 8 shows the relative content of compounds determined by gas chromatography and the calculation method of weighted average molecular weight.

[0137]

[0138]

[0139] Weighted average molecular weight = ∑ normalized relative content% × molecular weight = 94.11 × 16.11% + 108.14 × 7.52% + ... + 154.17 × 25.64% = 128.82

[0140] Table 8 shows that the weighted average molecular weight of phenols is 128.82, which differs by 3.89% (less than 5%) from the molecular weight of guaiacol used in the calculation, 124.

[0141] Corrected total phenol content = absolute content (in terms of guaiacol) 7.44% / 124*128.82=7.73%, then the corrected total phenol content is distributed to the absolute content of each phenolic substance according to the normalized relative percentage content, see the last column of data in Table 7a. There is one ketone substance in Table 7a, and the absolute content calculated separately is: guaiacol absolute content 1.62% / guaiacol relative content 13.42%*3-methyl-2-hydroxy-cyclopentenolone relative percentage content 1.24%=0.15%.

[0142] Example 7

[0143] 1) Prepare 10% NaOH aqueous solution for later use;

[0144] 2) diluting the wood vinegar with distilled water to n times, n=5;

[0145] 3) Take the diluted wood vinegar 100g and pour it into 200ml beaker respectively, a total of 5 beakers, and the 1st to 5th beakers add pure 0g, 0.3g, 0.6g, 0.9g, 1.2g acetic acid for standby use;

[0146] 4) Use 10% NaOH aqueous solution for neutralization titration, add 0.2g NaOH aqueous solution each time, measure and record the pH value and the number of grams of NaOH aqueous solution added under stirring speed of 120r / min, and add until the pH value is ≥12.0;

[0147] 5) Draw a curve with the grams of NaOH aqueous solution as the X-axis and the pH value as the Y-axis. The grams of NaOH on the Y-axis corresponding to the point where pH = 7.25 is the grams of NaOH consumed.

[0148] 6) Establish a linear regression equation based on the new X-axis representing the grams of acetic acid added (0 g, 0.3 g, 0.6 g, 0.9 g, 1.2 g) and the Y-axis representing the grams of NaOH consumed, Y1=a1X1+b1;

[0149] 7) Calculation of total acid percentage: Let X1=0, and Y1 be the grams of NaOH consumed by the wood vinegar dilution. Then the organic acid percentage concentration of the wood vinegar stock solution is: 10×Y1 / 40×60×100%;

[0150] 8) In addition, 100 g of the diluted wood vinegar was poured into 200 ml beakers, a total of 5 beakers, and 0 g, 0.31 g, 0.62 g, 0.93 g, and 1.24 g of guaiacol were added to the 1st to 5th beakers respectively for later use;

[0151] 9) Use 10% NaOH aqueous solution for neutralization titration, add 0.2g NaOH aqueous solution each time, measure and record the pH value and the number of grams of NaOH aqueous solution added under stirring speed of 120r / min, and add until the pH value is ≥12.0;

[0152] 10) Draw a curve with the grams of NaOH as the X-axis and the pH value as the Y-axis, find the point of pH=7.25 and the point of pH=11.15 on the Y-axis of the curve, and the difference between the grams of NaOH at the two points on the Y-axis is the grams of NaOH consumed by the guaiacol reaction;

[0153] 11) A linear regression equation was established based on the difference between the number of grams of guaiacol added on the X-axis (0 g, 0.31 g, 0.62 g, 0.93 g, and 1.24 g after purification) and the NaOH consumed on the Y-axis, Y2=a2X2+b2;

[0154] 12) Calculation of total phenol percentage: Let X2 = 0, and Y2 be the grams of NaOH consumed by the biomass dry distillation acid dilution solution. Then the percentage concentration of phenol (in terms of guaiacol) in the wood vinegar sample is: 5×Y2 / 40×124×100%;

[0155] Fig.10 Taking wood vinegar WV as an example, our method is used to determine the content of organic acid OA (in terms of acetic acid). '100gDWV10+0.0gAA' means diluting WV to 5 times with distilled water, then taking 100g of the diluted wood vinegar, adding 0.0g acetic acid. The X-axis represents the number of times 10% NaOH solution is added, 0.2g is added each time, and the Y-axis represents the pH value.

[0156] Fig.11 Taking wood vinegar as an example, the content of phenolic substances (calculated as guaiacol) was determined. 100gBV20+0.0gG, that is, dilute the wood vinegar to 5 times with distilled water, take 100g of the diluted wood vinegar, and add 0.0g guaiacol. The X-axis represents the number of times 10% NaOH solution was added, 0.2g was added each time, and the Y-axis represents the pH value. The mean and variance of the 3 repeated data were calculated by Tukey's at the p<0.05 level.

[0157] Table 8 Calculation of organic acid content (in acetic acid) and phenol content (in guaiacol) in wood vinegar

[0158]

[0159] Table 8

[0160] As shown in Table 8, the organic acid and classified contents in wood vinegar using the regression method are reported as 5.04% and 3.47, and the values ​​determined using the simplified method are 5.10% and 3.10%, respectively. The maximum difference between the two is more than 10%. Therefore, if the error needs to be controlled within 10% during the determination, both methods can be used. However, if higher accuracy is required, such as controlling the error to no more than 50%, the regression method is more accurate than the simplified method.

[0161] Example 8

[0162] 1) Prepare 10% NaOH aqueous solution for later use;

[0163] 2) dilute the straw vinegar solution to n times with distilled water, n=10;

[0164] 3) Take 100g of the diluted straw vinegar solution and pour it into 200ml beakers, a total of 5 beakers, and add 0g, 0.3g, 0.6g, 0.9g, and 1.2g of pure acetic acid to the 1st to 5th beakers respectively for standby use;

[0165] 4) Use 10% NaOH aqueous solution for neutralization titration, add 0.2g NaOH aqueous solution each time, measure and record the pH value and the number of grams of NaOH aqueous solution added under stirring speed of 120r / min, and add until the pH value is ≥12.0;

[0166] 5) Draw a curve with the grams of NaOH aqueous solution as the X-axis and the pH value as the Y-axis. The grams of NaOH on the Y-axis corresponding to the point where pH = 7.25 is the grams of NaOH consumed.

[0167] 6) A linear regression equation is established based on the new X-axis for the grams of acetic acid added (0g, 0.3g, 0.6g, 0.9g, 1.2g) and the Y-axis for the grams of NaOH consumed, Y1 = a1X1 + b 1；

[0168] 7) Calculation of total acid percentage: Let X1=0, and Y1 be the grams of NaOH consumed by the straw vinegar dilution. Then the organic acid percentage concentration of the straw vinegar stock solution is: 10×Y1 / 40×60×100%;

[0169] 8) In addition, 100 g of the diluted straw vinegar solution was poured into 200 ml beakers, a total of 5 beakers, and 0 g, 0.31 g, 0.62 g, 0.93 g, and 1.24 g of guaiacol were added to the 1st to 5th beakers respectively for later use;

[0170] 9) Use 10% NaOH aqueous solution for neutralization titration, add 0.2g NaOH aqueous solution each time, measure and record the pH value and the number of grams of NaOH aqueous solution added under stirring speed of 120r / min, and add until the pH value is ≥12.0;

[0171] 10) Draw a curve with the grams of NaOH as the X-axis and the pH value as the Y-axis, find the point of pH=7.25 and the point of pH=11.15 on the Y-axis of the curve, and the difference between the grams of NaOH at the two points on the Y-axis is the grams of NaOH consumed by the guaiacol reaction;

[0172] 11) A linear regression equation was established based on the difference between the number of grams of guaiacol added (0 g, 0.31 g, 0.62 g, 0.93 g, and 1.24 g after purification) on the X-axis and the NaOH consumed on the Y-axis, Y2=a2X2+b 2；

[0173] 12) Calculation of total phenol percentage: Let X2 = 0, and Y2 be the grams of NaOH consumed by the straw dilution solution. Then the percentage concentration of phenol (in terms of guaiacol) in the straw vinegar solution sample is: 10×Y2 / 40×124×100%;

[0174] Fig.13 Taking straw vinegar as an example, our method was used to determine the content of organic acid OA (measured in acetic acid)

[0175] '100gDWV10+0.0gAA' means diluting the straw vinegar solution to 10 times with distilled water, then taking 100g of the diluted straw vinegar solution and adding 0.0g acetic acid. The X-axis indicates the number of times 10% NaOH solution was added, 0.2g was added each time, and the Y-axis indicates the pH value; the mean and variance of the 3 repeated data were calculated by Tukey's at the p<0.05 level.

[0176] Fig.13 Taking straw vinegar as an example, our method was used to determine the phenol content (measured in guaiacol)

[0177] '100gDWV10+0.0gG' means diluting the straw vinegar solution to 10 times with distilled water, then taking 100g of the diluted straw vinegar solution and adding 0.0g guaiacol. The X-axis indicates the number of times 10% NaOH solution was added, 0.2g was added each time, and the Y-axis indicates the pH value; the mean and variance of the 3 repeated data were calculated by Tukey's at the p<0.05 level.

[0178] Table 9 calculates the organic acid content (in terms of acetic acid) and phenolic content (in terms of guaiacol) of wood vinegar.

[0179]

[0180] Table 9

[0181] As shown in Table 9, the organic acid and phenol contents in wood vinegar using the regression method were 8.22% and 4.09%, respectively, and the simplified method was 8.10% and 3.72%, respectively. The maximum difference between the two methods exceeded 10%. Therefore, if the error needs to be controlled within 10% during the determination, both methods can be used. However, if higher accuracy is required, such as controlling the error to no more than 5%, the regression method is more accurate than the simplified method.

[0182] The abbreviations in this article are as follows: PA-biomass dry distillation acid, OA-organic acid, AA-acetic acid, BV-bamboo vinegar, WV-wood vinegar, SV-straw vinegar, DBV-diluted bamboo vinegar, DWV-diluted wood vinegar, DSV-diluted straw vinegar. The present invention is not only used in factories but also in laboratories to determine the absolute content of effective components in biomass dry distillation acid, and can also be used to design and produce related measuring instruments and equipment.

[0183] The method of the present invention is simple and practical, and can measure the absolute content of effective ingredients at low cost. The present invention does not require professional training, is easy to use, and has high efficiency. The present invention provides the most critical scientific basis, rules and calculation methods for establishing a practical and internationally applicable commercial technical standard, for the real commercial application of PA and the sustainable development of the biochar industry. The ideas and methods of the present invention may also be extended to the determination of the absolute content of many other naturally extracted compounds, such as natural products that require a multi-component mixture of organic acids and phenolic substances; the present invention is not only used in factories but also in laboratories to determine the absolute content of effective ingredients in biomass dry distillation acid, and can also be used to design and produce related measurement instruments and equipment, solving the problem of the most basic cornerstone of the absolute content determination technology of organic acids and phenolic substances in biomass dry distillation acid.

[0184] It should be noted that the above is only a specific embodiment of the present invention. Obviously, the present invention is not limited to the above embodiment, and there are many variations. In short, all variations that can be directly derived or associated with the content disclosed by ordinary technicians in this field should be considered as the protection scope of the present invention.

Claims

1. A method for simply determining the absolute content of organic acids and phenols in biomass dry distillation acid, characterized in that: The steps include: Step S1: preparing an alkali solution with a concentration between 5% and 10%, wherein the concentration of the alkali solution is set to p, and the molecular weight of the alkali is set to q, and then obtaining a standby alkali solution; Step S2: diluting the biomass dry distillation acid stock solution with distilled water to n times, wherein n is a natural number between 5 and 20; Step S3: taking 100 g of the diluted biomass dry distillation acid stock solution and pouring it into five 200 ml beakers respectively, and adding 0 g, 0.3 g, 0.6 g, 0.9 g, and 1.2 g of pure acetic acid into the first to fifth beakers respectively for standby use; Step S4: neutralize and titrate with the reserve alkali solution, add 0.2 g of the reserve alkali solution to the five beakers each time, measure and record the pH value and the number of grams of the reserve alkali solution added under a stirring speed of 120 r / min, and continue to add until the pH value is ≥12.0; Step S5: draw a curve with the grams of the standby alkali solution as the X-axis and the pH value as the Y-axis, and find the grams of the standby alkali solution on the Y-axis corresponding to the nearest point of pH=7.25 on the Y-axis of the curve, which is the grams of alkali consumed; Step S6: A linear regression equation is established based on the new X-axis as the increased grams of pure acetic acid including 0g, 0.3g, 0.6g, 0.9g, and 1.2g and the corresponding grams of the reserved alkaline solution consumed as the new Y-axis, and the equation is set as Y1=a1X1+b 1； Step S7: Calculation of total acid percentage: Let X1=0, Y1 value be the standby alkali solution consumed by the dilution of the biomass dry distillation acid stock solution, and the molecular weight of the organic acid be set to c, then the absolute content of the organic acid in the biomass dry distillation acid stock solution is: n×Y1 / q×c×p×100%; Step S8: taking 100 g of the diluted biomass dry distillation acid stock solution and pouring it into 5 new 200 ml beakers respectively, adding 0 g, 0.31 g, 0.62 g, 0.93 g, and 1.24 g of phenolic substances into the first to fifth beakers respectively, and then setting aside; Step S9: neutralize and titrate with the reserve alkali solution, add 0.2 g of the reserve alkali solution to the five beakers each time, measure and record the pH value and the number of grams of the reserve alkali solution added at a stirring speed of 120 r / min, and continue to add until the pH value is ≥12.0; Step S10: draw a curve with the grams of the reserve alkali solution as the X-axis and the pH value as the Y-axis, find two points on the Y-axis of the curve where pH=7.25 and pH=11.15, and the difference between the grams of the reserve alkali solution consumed at the two points on the Y-axis is the grams of the reserve alkali solution consumed by the reaction of the phenolic substance; Step S11: Establish a linear regression equation based on the new X-axis, which is the grams of the added phenolic substances, including 0g, 0.31g, 0.62g, 0.93g, and 1.24g, and the Y-axis, which is the grams of the spare alkaline solution consumed by the reaction of the phenolic substances, and the equation is set as Y2=a2X2+b2; Step S12: Calculation of total phenol percentage: Let X2=0, Y2 value be the grams of alkali consumed by phenolic substances in the diluted biomass dry distillation acid stock solution, the molecular weight of phenol is set to d, and the absolute content of phenol in the biomass dry distillation acid stock solution is: n×Y2 / q×d×p×100%.

2. The method for simply determining the absolute content of organic acids and phenols in biomass dry distillation acid according to claim 1, characterized in that: The simplified steps are as follows: dilute the biomass dry distillation acid stock solution to n times, take 100g of the dilution, titrate with a 10% alkali solution, draw a curve with the grams of 10% alkali as the X-axis and the pH value as the Y-axis, find the X value of pH = 7.25 on the X-axis of the curve a Value and pH = 11.15 X b The two closest points of the value correspond to the two points Y on the Y axis a and Y b , where Y a Y is the number of grams of 10% alkaline solution consumed by biomass dry distillation acid stock solution, b Y is the sum of grams of 10% alkaline solution consumed by adding phenolic substances to the biomass dry distillation acid stock solution. b -Y a is the number of grams of 10% alkaline solution consumed by the reaction of phenolic substances. The absolute contents of organic acids and phenols in the biomass dry distillation acid stock solution are calculated based on the molecular weight and the dilution multiple. The absolute content of organic acids in the biomass dry distillation acid stock solution is calculated as Y a ×10%×c / q×n×100%, calculate the absolute content of phenol in the biomass dry distillation acid stock solution as (Y b -Y a )×10%×d / q×n×100%.

3. The method for simply determining the absolute content of organic acids and phenols in biomass dry distillation acid according to claim 2, characterized in that: If the organic acid is acetic acid, the absolute content of acetic acid in the biomass dry distillation acid stock solution is Y a ×10%×60 / q×n×100%.

4. The method for simply determining the absolute content of organic acids and phenols in biomass dry distillation acid according to claim 2, characterized in that: If the phenol is guaiacol, the absolute content of guaiacol in the biomass dry distillation acid stock solution is (Y b -Y a )×10%×124 / q×n×100%.

5. The method for simply determining the absolute content of organic acids and phenols in biomass dry distillation acid according to claim 1, characterized in that: The method for determining and calculating the absolute content of other substances in the biomass dry distillation acid stock solution is as follows: according to the relative content determined by the recognized mass spectrometry GCMS method, the percentage of all phenolic substances is normalized, and then the weighted average molecular weight m of the phenolic substances is calculated, wherein there are n hydroxyl groups, the weighted average molecular weight m of hydroquinone is m=110 / 2=55, and the weighted average molecular weight m of hydroquinone is m=126 / 3=42, and the molecular weight is corrected by its molecular weight / n as the correction molecular weight, and the total phenolic content after correction is: the absolute content of phenols before correction / d×m. The relative content of other substances is determined by combining the GCMS method, and the other substances include aldehydes, ketones, alcohols, and esters. The absolute content of the above other substances is calculated according to the same proportion. If the absolute content of total phenols is 6%, the sum of the relative contents of various phenolic substances in GCMS is 60%, and the relative content of ethyl acetate is 2%, then the absolute content of ethyl acetate is: 6% / 60%×2%=0.2%.

6. The method for simply determining the absolute content of organic acids and phenols in biomass dry distillation acid according to claim 1, characterized in that: The biomass dry distillation acid includes any one of bamboo vinegar, wood vinegar or straw vinegar, and also includes raw liquid, liquid collected after distillation or activated carbon filtration, and also includes bamboo tar, wood tar or straw tar.

7. The method for simply determining the absolute content of organic acids and phenols in biomass dry distillation acid according to claim 1, characterized in that: The alkaline solution is KOH or NaOH.

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