Construction method of comprehensive evaluation system for target volatile organic compounds adsorbed by commercial activated carbon

Abstract

The invention discloses a construction method of a comprehensive evaluation system for adsorbing target volatile organic compounds (VOCs) by commercial activated carbon, and belongs to the technical field of adsorption and removal of environmental pollutants. The construction method specifically comprises the following steps: (1) constructing a comprehensive evaluation index system of the target volatile organic compound adsorbed by the commercial activated carbon through an analytic hierarchy process, wherein the comprehensive evaluation index system comprises a physical performance parameter (W), a chemical performance parameter (H) and a target volatile organic compound adsorption capacity (Q) of the commercial activated carbon; (2) establishing a correlation index weight (k); (3) normalized data processing; (4) calculating a comprehensive evaluation index (EI) of the target volatile organic compound adsorbed by the commercial activated carbon; and (5) sorting, and screening out the optimal commercial activated carbon for adsorbing the target volatile organic compounds. The construction method disclosed by the invention can be used for comprehensively evaluating commercial activated carbon in the market and guiding targeted selection and application of activated carbon adsorption materials in different VOCs (Volatile Organic Compounds) industries.

Description

Technical Field

[0001] This invention relates to the field of environmental pollutant adsorption and removal technology, and more specifically to a method for constructing a comprehensive evaluation system for the adsorption of target volatile organic compounds by commercial activated carbon. Background Technology

[0002] Activated carbon, with its well-developed pore structure and abundant specific surface area, exhibits excellent adsorption performance and is widely used in various volatile organic compound (VOCs) industries. Therefore, the rational selection of suitable adsorption materials for the adsorption and removal of target VOCs has significant application value.

[0003] Currently, the selection of activated carbon adsorption materials remains highly complex. On the one hand, the market offers a wide variety of commercially available activated carbons, each with diverse products and complex performance indicators. For example, common indicators for activated carbon include shape, strength, pore size, moisture content, ash content, pH value, iodine value, and methylene blue decolorization performance. However, these indicators cannot provide a direct basis for selecting activated carbon to remove a specific VOCs pollutant. On the other hand, industrial VOCs emission sources are numerous, with significant differences in emission composition and levels. Different VOCs place varying requirements on adsorption materials, leading to diverse needs in the selection of activated carbon adsorption materials.

[0004] Given the diversity of VOCs and the differences in activated carbon indicators, there is currently no comprehensive evaluation system to screen the best adsorbent.

[0005] Therefore, how to construct a comprehensive evaluation system for the adsorption of target VOCs by commercial activated carbon is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] In view of this, the purpose of this invention is to provide a method for constructing a comprehensive evaluation system for the adsorption of target volatile organic compounds by commercial activated carbon, so as to overcome the shortcomings of the prior art.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A method for constructing a comprehensive evaluation system for the adsorption of target volatile organic compounds by commercial activated carbon, specifically including the following steps:

[0009] (1) A comprehensive evaluation index system for the adsorption of target volatile organic compounds by commercial activated carbon was constructed by the analytic hierarchy process, including the physical performance parameters (W), chemical performance parameters (H) and adsorption capacity (Q) of target volatile organic compounds of commercial activated carbon.

[0010] (2) Establish the correlation index weights (k) between the physical performance parameters (W), chemical performance parameters (H), and target volatile organic compound adsorption capacity (Q) of commercial activated carbon;

[0011] (3) Normalize the physical property parameters (W) and chemical property parameters (H) of commercial activated carbon.

[0012] (4) Based on the correlation index weight (k) and the normalized data processing results, calculate the comprehensive evaluation index (EI) for the adsorption of target volatile organic compounds by commercial activated carbon;

[0013] (5) The comprehensive evaluation index (EI) of a series of commercial activated carbons adsorbing target volatile organic compounds was ranked, and the best commercial activated carbon for adsorbing target volatile organic compounds was selected.

[0014] Furthermore, in step (1) above, the physical performance parameters (W) include specific surface area (W1) and pore volume (W2), which are obtained by BET characterization tests or provided by the activated carbon material manufacturer.

[0015] Furthermore, in step (1) above, the chemical performance parameter (H) includes acidic functional groups (H1) and basic functional groups (H2), which are obtained by Boehm titration testing or provided by the activated carbon material manufacturer. The Boehm titration test method for acidic functional groups is as follows: the content of acidic functional groups is calculated using the amount of NaOH consumed; the Boehm titration test method for basic functional groups is as follows: the content of basic functional groups is calculated using the amount of HCl consumed.

[0016] Furthermore, in step (1) above, the analytic hierarchy process (AHP) specifically refers to:

[0017]

[0018] In the formula, Cij is the performance parameter i of the j-type commercial activated carbon; W1j is the specific surface area (W1) of the j-type commercial activated carbon; W2j is the pore volume (W2) of the j-type commercial activated carbon; H1j is the acidic functional group (H1) of the j-type commercial activated carbon; H2j is the basic functional group (H2) of the j-type commercial activated carbon; and n is the sample size of the commercial activated carbon.

[0019] Furthermore, in step (1) above, the target volatile organic compound adsorption capacity (Q) includes the static equilibrium adsorption capacity and the dynamic equilibrium adsorption capacity, which is obtained by static or dynamic adsorption equilibrium experiments.

[0020] The formula for calculating the static equilibrium adsorption capacity is:

[0021]

[0022] In the formula, Q is the adsorption capacity of the target volatile organic compound (mg / g); M1 is the mass of the commercial activated carbon before adsorbing the target volatile organic compound (g); M2 is the mass of the commercial activated carbon after adsorbing the target volatile organic compound to equilibrium (g).

[0023] The formula for calculating the dynamic equilibrium adsorption capacity is:

[0024]

[0025] In the formula, Q is the adsorption capacity of the target volatile organic compound (mg / g); m is the mass of commercial activated carbon (g); V is the gas flow rate of the target volatile organic compound (mL / min); t is the dynamic adsorption equilibrium time (min); and Cin is the inlet concentration of the target volatile organic compound (mg / m³). 3 Cout is the outlet concentration of the target volatile organic compound (mg / m³). 3 ).

[0026] Furthermore, in step (2) above, the weights (k) of the correlation index are initially weighted (r) for the linear correlation of the comprehensive evaluation index system using the Spearman analysis method. Based on a base of 0, the initial weighted index (r) is then reweighted (k) again. The Spearman linear correlation calculation formula is as follows:

[0027]

[0028] In the formula, ki is the linear correlation coefficient between the performance parameter i of commercial activated carbon and the target volatile organic compound adsorption capacity Q; di is the rank difference between the corresponding data points between the performance parameter i of commercial activated carbon and the target volatile organic compound adsorption capacity Q; and n is the sample size of commercial activated carbon.

[0029] Furthermore, in step (3) above, the normalized data processing adopts the Min-Max standard, and the calculation formula is as follows:

[0030]

[0031] In the formula, NCij represents the performance parameter i of the j-type commercial activated carbon after normalized data processing; Cij represents the performance parameter i of the j-type commercial activated carbon; and n represents the sample size of the commercial activated carbon.

[0032] Furthermore, in step (4) above, the formula for calculating the comprehensive evaluation index (EI) is as follows:

[0033]

[0034] In the formula, EIj is a comprehensive evaluation index of the relationship between the physical performance parameters (W), chemical performance parameters (H), and target volatile organic compound adsorption capacity (Q) of j commercial activated carbons; ki is the linear correlation coefficient between the performance parameter i of commercial activated carbon and the target volatile organic compound adsorption capacity Q; NCij is the performance parameter i of j commercial activated carbons after normalized data processing.

[0035] As can be seen from the above technical solution, compared with the prior art, the beneficial effects of the present invention are as follows:

[0036] 1. This invention relates to a method for constructing a comprehensive evaluation system for the adsorption of target volatile organic compounds (VOCs) by commercial activated carbon, comprising the following steps: obtaining the physical and chemical performance parameters of activated carbon materials and their adsorption capacity for target VOCs; constructing a comprehensive evaluation system for the adsorption of target VOCs by activated carbon, based on the relationship between the physical and chemical performance parameters of activated carbon and the adsorption capacity of target VOCs; evaluating the linear correlation between the physical and chemical performance parameters of activated carbon and the adsorption capacity, and assigning weights to the comprehensive evaluation indicators using correlation coefficients; normalizing the physical and chemical performance parameters of activated carbon, and calculating the comprehensive evaluation factor for the adsorption of target VOCs by activated carbon based on the weighted indicator parameters, providing scientific guidance for the selection of VOCs adsorption and removal materials from different industrial sources.

[0037] 2. The construction method of this invention is a mechanism for determining and decomposing the weights of relevant indicators for the adsorption capacity of target VOCs by activated carbon, which comprehensively considers the performance parameters of activated carbon itself. The performance parameters of activated carbon include physical properties (specific surface area, pore volume) and chemical properties (acidic functional groups, basic functional groups). By constructing a multi-indicator comprehensive evaluation system for the adsorption of target VOCs by activated carbon, and combining the linear correlation between the performance parameters of activated carbon and the adsorption capacity of target VOCs with the normalization of performance data, the weights of the indicators are scientifically allocated to ensure the fairness and rationality of the influence of the performance parameters of activated carbon on the adsorption of target VOCs.

[0038] 3. The construction method of this invention can comprehensively evaluate commercially available activated carbon and guide different VOCs industries to make targeted selections and applications of activated carbon adsorption materials. Attached Figure Description

[0039] Figure 1 This is a process flow diagram of the construction method of the comprehensive evaluation system for adsorbing target volatile organic compounds (VOCs) using commercial activated carbon in Example 1. Detailed Implementation

[0040] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] Example 1

[0042] The method for constructing a comprehensive evaluation system for the adsorption of target volatile organic compounds (VOCs) by commercial activated carbon includes the following steps:

[0043] (1) A comprehensive evaluation index system for the adsorption of target volatile organic compounds by commercial activated carbon was constructed by the analytic hierarchy process, including the physical performance parameters (W), chemical performance parameters (H) and adsorption capacity (Q) of target volatile organic compounds of commercial activated carbon.

[0044] Among them, the physical performance parameters (W) include specific surface area (W1) and pore volume (W2), and the chemical performance parameters (H) include acidic functional groups (H1) and basic functional groups (H2), as shown in Table 1;

[0045] Table 1. Comprehensive evaluation index system for VOCs adsorption by commercial activated carbon

[0046]

[0047] Ten commercial activated carbons were obtained from the market, and their specific surface area (W1) and pore volume (W2) were obtained by BET characterization tests, as shown in Table 2.

[0048] Table 2 Physical property parameters of 10 commercial activated carbons

[0049] serial number <![CDATA[Specific surface area (m 2 / g)]]> <![CDATA[Pore volume (cm 3 / g)]]> 1 883 0.07 2 886 0.10 3 1247 0.63 4 1151 0.18 5 997 0.10 6 969 0.05 7 851 0.05 8 671 0.26 9 1358 0.58 10 1851 0.70

[0050] Its acidic functional groups (H1) and basic functional groups (H2) were obtained by Boehm titration, as shown in Table 3;

[0051] Table 3 Chemical performance parameters of 10 commercial activated carbons

[0052]

[0053]

[0054] The adsorption capacity (Q) of commercial activated carbon for target VOCs, taking the static adsorption of m-xylene by activated carbon as an example, is shown in Table 4.

[0055] Table 4. Static adsorption capacity of 10 commercial activated carbons for m-xylene

[0056]

[0057] A comprehensive evaluation index system is established using the analytic hierarchy process, as shown in the following formula:

[0058]

[0059] (2) Establish the correlation index weights (k) between the physical performance parameters (W), chemical performance parameters (H), and target volatile organic compound adsorption capacity (Q) of commercial activated carbon;

[0060] Among them, k is preliminarily weighted (r) for the linear correlation of the comprehensive evaluation index system using the Spearman analysis method, as shown in Table 5;

[0061] Table 5. Correlation between the performance indicators of activated carbon and the static adsorption capacity of m-xylene

[0062]

[0063] Note: *p<0.05**p<0.01;

[0064] The initial weighted index (r) is modified by a second weighting (k) based on a base of 0, as shown in Table 6.

[0065] Table 6. Weighting Indicators of the Comprehensive Evaluation System for Activated Carbon Adsorption of m-xylene

[0066] k1 k2 k3 k4 Weighting indicators 0.797 0.441 0.269 -0.536

[0067] (3) Normalize the physical property parameters (W) and chemical property parameters (H) of commercial activated carbon, as shown in Table 7.

[0068] Table 7. Normalized performance indicators of 10 commercial activated carbons

[0069]

[0070] (4) Based on the correlation index weight (k) and the normalized data processing results, the comprehensive evaluation index (EI) of commercial activated carbon adsorbing m-xylene was calculated, as shown in Table 8.

[0071] Table 8. Ranking of indicators for comprehensive evaluation of adsorption of m-xylene by 10 commercial activated carbons

[0072]

[0073] (5) The comprehensive evaluation index (EI) of 10 commercial activated carbons adsorbing m-xylene was ranked, and the best commercial activated carbon for adsorbing m-xylene was selected based on the maximum EI index.

[0074] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined in this patent may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown in this patent, but is to be accorded the widest scope consistent with the principles and novel features disclosed in this patent.

Claims

1. A method for constructing a comprehensive evaluation system for the adsorption of target volatile organic compounds by commercial activated carbon, characterized in that, Specifically, the following steps are included: (1) A comprehensive evaluation index system for the adsorption of target volatile organic compounds by commercial activated carbon was constructed by the analytic hierarchy process, including the physical performance parameters (W), chemical performance parameters (H) and adsorption capacity (Q) of target volatile organic compounds of commercial activated carbon. (2) Establish the correlation index weights (k) between the physical performance parameters (W), chemical performance parameters (H), and target volatile organic compound adsorption capacity (Q) of commercial activated carbon; (3) Normalize the physical property parameters (W) and chemical property parameters (H) of commercial activated carbon. (4) Based on the correlation index weight (k) and the normalized data processing results, calculate the comprehensive evaluation index (EI) for the adsorption of target volatile organic compounds by commercial activated carbon; (5) The comprehensive evaluation index (EI) of a series of commercial activated carbons adsorbing target volatile organic compounds was ranked, and the best commercial activated carbon for adsorbing target volatile organic compounds was selected.

2. The method for constructing a comprehensive evaluation system for the adsorption of target volatile organic compounds by commercial activated carbon according to claim 1, characterized in that, In step (1), the physical performance parameters (W) include specific surface area (W1) and pore volume (W2).

3. The method for constructing a comprehensive evaluation system for the adsorption of target volatile organic compounds by commercial activated carbon according to claim 2, characterized in that, In step (1), the chemical performance parameter (H) includes acidic functional groups (H1) and basic functional groups (H2).

4. The method for constructing a comprehensive evaluation system for the adsorption of target volatile organic compounds by commercial activated carbon according to claim 3, characterized in that, In step (1), the analytic hierarchy process specifically refers to: In the formula, Cij represents the performance parameter i of the j-th commercial activated carbon; W1j is the specific surface area (W1) of commercial activated carbon of type j; W2j represents the pore volume (W2) of commercial activated carbon of type j; H1j represents the acidic functional group (H1) of commercial activated carbon of type j; H2j represents the basic functional group (H2) of commercial activated carbon of type j; and n represents the sample size of commercial activated carbon.

5. The method for constructing a comprehensive evaluation system for the adsorption of target volatile organic compounds by commercial activated carbon according to claim 1, characterized in that, In step (1), the target volatile organic compound adsorption capacity (Q) includes the static equilibrium adsorption capacity and the dynamic equilibrium adsorption capacity; The formula for calculating the static equilibrium adsorption capacity is: In the formula, Q is the adsorption capacity of the target volatile organic compound (mg / g); M1 is the mass of the commercial activated carbon before adsorbing the target volatile organic compound (g); M2 is the mass of the commercial activated carbon after adsorbing the target volatile organic compound to equilibrium (g). The formula for calculating the dynamic equilibrium adsorption capacity is as follows: In the formula, Q is the adsorption capacity of the target volatile organic compound (mg / g); m is the mass of commercial activated carbon (g); V is the gas flow rate of the target volatile organic compound (mL / min); t is the dynamic adsorption equilibrium time (min); and Cin is the inlet concentration of the target volatile organic compound (mg / m³). 3 Cout is the outlet concentration of the target volatile organic compound (mg / m³). 3 ).

6. The method for constructing a comprehensive evaluation system for the adsorption of target volatile organic compounds by commercial activated carbon according to claim 1, characterized in that, In step (2), the Spearman linear correlation calculation formula for the correlation index weight (k) is as follows: In the formula, ki is the linear correlation coefficient between the performance parameter i of commercial activated carbon and the target volatile organic compound adsorption capacity Q; di is the rank difference between the corresponding data points of the performance parameter i of commercial activated carbon and the target volatile organic compound adsorption capacity Q; n represents the sample size of commercial activated carbon.

7. The method for constructing a comprehensive evaluation system for the adsorption of target volatile organic compounds by commercial activated carbon according to claim 1, characterized in that, In step (3), the normalized data processing adopts the Min-Max standard, and the calculation formula is as follows: In the formula, NCij represents the performance parameter i of the j-type commercial activated carbon after normalized data processing; Cij represents the performance parameter i of the j-type commercial activated carbon; and n represents the sample size of the commercial activated carbon.

8. The method for constructing a comprehensive evaluation system for the adsorption of target volatile organic compounds by commercial activated carbon according to claim 1, characterized in that, In step (4), the formula for calculating the comprehensive evaluation index (EI) is as follows: In the formula, EIj is a comprehensive evaluation index of the relationship between the physical performance parameters (W), chemical performance parameters (H), and target volatile organic compound adsorption capacity (Q) of a type j commercial activated carbon; ki is the linear correlation coefficient between the performance parameter i of the commercial activated carbon and the target volatile organic compound adsorption capacity Q. NCij represents the performance parameter i of j types of commercial activated carbon after normalized data processing.

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