Modified activated carbon and preparation method therefor, and catalyst and use thereof

Abstract

The present invention provides a modified activated carbon and a preparation method therefor, and a catalyst and the use thereof. The modified activated carbon comprises an activated carbon matrix, wherein the activated carbon matrix comprises a plurality of micropores and a plurality of mesopores, and at least some of the micropores are bonded with a modifier by means of chemical bonds. The modified activated carbon meets the following conditions: T1<T2, 0.4≤S1 / S2≤0.6, and 0.8≤S3 / S4≤1, wherein T1 is the decomposition temperature of the modifier; T2 is the initial decomposition temperature of the activated carbon matrix; S1 is the micropore specific surface area of the modified activated carbon; S2 is the micropore specific surface area of the modified activated carbon after calcination at a temperature greater than T1, but less than T2; S3 is the mesopore specific surface area of the modified activated carbon; and S4 is the mesopore specific surface area of the modified activated carbon after calcination at a temperature greater than T1 but less than T2. In the present application, a modifier is bonded with the micropore channels of the activated carbon matrix to achieve occupation of the micropore channels, thereby achieving precise control over the properties of the pore channels of the activated carbon.

Description

Modified activated carbon, preparation method thereof, catalyst and application thereof

[0001] The present application claims priority to the Chinese patent application No. 202410437382.8, filed on April 11, 2024, and entitled "Modified activated carbon, preparation method thereof, catalyst and application thereof", the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] The present application relates to the technical field of activated carbon modification, in particular to a modified activated carbon, a preparation method thereof, a catalyst and an application thereof. BACKGROUND

[0003] Activated carbon is a common adsorbent and a common catalyst carrier material. Activated carbon is rich in micropore, mesopore and macropore structures. In order to meet different application scenarios, the pore structure of activated carbon generally needs to be modified. The modification technology for the pore structure of activated carbon currently mainly includes acid-base modification, oxidation-reduction modification and adsorption modification. In the acid-base modification process, dangerous chemicals with corrosive properties are usually involved. In the oxidation-reduction modification, substances with oxidation-reduction properties are usually treated under strong acid or alkali conditions at a certain temperature to achieve modification. The process does not have the characteristics of green environmental protection and is not conducive to industrial scale production. Whether the adsorption modification process is environmentally friendly mainly depends on the chemical characteristics of the adsorbed substances. Although the current modification technology successfully modifies the surface properties of activated carbon, it cannot precisely control the change of the pore properties.

[0004] Precise control of the pore properties of activated carbon will help to improve the utilization rate of the supported catalyst. Taking the hydrogenation reaction process of bisphenol A with a large molecular size as an example, bisphenol A molecules and hydrogen molecules need to diffuse to the vicinity of the catalyst active center in the reaction process, and then occur hydrogenation reaction in a certain range to generate hydrogenated bisphenol A target product. However, the width of bisphenol A molecule is large and it is difficult to enter the micropore. The specific surface area of micropore in conventional activated carbon accounts for about 60% of the total specific surface area. If conventional activated carbon is used as a carrier and the impregnation method is used to load the catalyst, a large amount of active phase will be attached to the micropore, and bisphenol A molecules are difficult to diffuse into the micropore. Ultimately, the active phase in the micropore cannot be fully utilized, the total utilization rate of the active phase is low, and the catalytic activity of the catalyst is reduced.

[0005] CONTENT

[0006] In view of this, the present application provides a modified activated carbon. The modified activated carbon is combined with a modifier in the micropore, so that the modifier blocks the micropore in the activated carbon, thereby regulating the proportion of the micropore specific surface area of the activated carbon matrix to the total specific surface area.

[0007] The application also provides a preparation method of the modified activated carbon, which can prepare the modified activated carbon and has a simple process.

[0008] The application also provides a catalyst, which uses the modified activated carbon as a carrier, so that the active phase is mainly loaded in the mesoporous pores, thereby increasing the contact probability of the raw material with a large molecular size and the active phase, and improving the catalytic performance of the catalyst.

[0009] The application also provides another catalyst, which is prepared by using the modified activated carbon, so that the catalyst not only helps to increase the contact probability of the raw material with a large molecular size and the active phase, but also opens the microporous channels of the modified activated carbon again by calcination, thereby improving the total pore volume and specific surface area of the modified activated carbon, and further improving the catalytic activity of the catalyst.

[0010] The application also provides a method for preparing hydrogenated bisphenol A by catalytic hydrogenation of bisphenol A, which uses any of the catalysts to catalyze, so that the method helps to improve the conversion rate of bisphenol A.

[0011] In a first aspect, the application provides a modified activated carbon, which comprises an activated carbon base and a plurality of micropores and mesopores, wherein at least part of the micropores are combined with a modifier through a chemical bond; and the modified activated carbon satisfies the following formulas 1 to 3: T1 < T2 Formula 1, 0.4 ≤ S1 / S2 ≤ 0.6 Formula 2, 0.8 ≤ S3 / S4 ≤ 1 Formula 3.

[0012] Wherein, T1 is the decomposition temperature of the modifier, T2 is the initial decomposition temperature of the activated carbon base, S1 is the micropore specific surface area of the modified activated carbon, S2 is the micropore specific surface area of the modified activated carbon after calcination at a temperature greater than T1 and less than T2, S3 is the mesopore specific surface area of the modified activated carbon, and S4 is the mesopore specific surface area of the modified activated carbon after calcination at a temperature greater than T1 and less than T2.

[0013] Preferably, the modifier is an amino acid.

[0014] Preferably, the modifier contains one or more of amidine, benzyl, and sulfhydryl functional groups.

[0015] Preferably, the modifier is one or more of arginine, phenylalanine, and methionine.

[0016] Preferably, the mesopore specific surface area of the modified activated carbon accounts for more than 50% of the total specific surface area.

[0017] Preferably, the micropore specific surface area of the modified activated carbon accounts for less than 50% of the total specific surface area.

[0018] Preferably, T2-T1≥50℃.

[0019] In a second aspect, the present application provides a method for preparing the modified activated carbon as described above, comprising the following steps:

[0020] The mixing system comprising the activated carbon matrix, the modifier and the solvent is stirred at 20-80℃ for 0.5-3h, and then filtered and dried to obtain the modified activated carbon; wherein the pH of the mixing system is 6-10.

[0021] In a third aspect, the present application provides a catalyst comprising a carrier and an active ingredient loaded on the carrier, wherein the carrier is the modified activated carbon as described above; and the active ingredient is at least partially loaded in the mesoporous pores of the modified activated carbon.

[0022] Preferably, the active ingredient comprises ruthenium trichloride.

[0023] In a fourth aspect, the present application provides a catalyst prepared by a method comprising the following steps:

[0024] The active ingredient is loaded in the mesoporous pores of the modified activated carbon by impregnation treatment to obtain an intermediate; and the intermediate is calcined at a temperature greater than T1 and less than T2 to remove the modifier, thereby obtaining the catalyst.

[0025] In a fifth aspect, the present application provides a method for catalytic hydrogenation of a benzene ring-containing chemical monomer, wherein the catalyst comprises the catalyst of any one of the above aspects.

[0026] Preferably, the benzene ring-containing chemical monomer is bisphenol A.

[0027] The modified activated carbon provided by the present application realizes the occupation of the microporous channels of the activated carbon matrix by combining the modifier with the microporous channels of the activated carbon matrix, thereby realizing the regulation of the proportion of the micropore specific surface area of the activated carbon matrix in the total specific surface area. Therefore, in the process of preparing the catalyst using the modified activated carbon as the carrier, the active phase is less likely to adhere to the surface of the microporous channels of the activated carbon carrier, but more likely to adhere to the surface of the mesoporous channels of the carrier, which is beneficial to increasing the probability of contact between the larger-sized raw material molecules and the active phase, thereby improving the catalytic activity of the catalyst.

[0028] Further, the modifier used in the modified activated carbon of the present application has a relatively low decomposition temperature, and optionally, the microporous channel structure of the activated carbon matrix is restored in the subsequent treatment process of the catalyst, thereby increasing the total pore volume and specific surface area of the modified activated carbon. Taking the bisphenol A hydrogenation reaction process as an example, the increase of the total pore volume and specific surface area is beneficial to creating an excess state of hydrogen molecules around the active phase in the reaction process, which can further improve the catalytic activity of the catalyst. BRIEF DESCRIPTION OF DRAWINGS

[0029] The accompanying drawings, which are incorporated herein and constitute part of this specification, illustrate embodiments consistent with the application and serve to explain the principles of the application, in which:

[0030] Figure 1 is the UV spectrum of the aqueous solution before and after modification of the activated carbon matrix A0 and the filtrate after washing the modified activated carbon A1 with water;

[0031] Figure 2 is the thermogravimetric characterization of the activated carbon matrix A0 and the modified activated carbon A1 in air atmosphere. DETAILED DESCRIPTION

[0032] To enable persons skilled in the art to better understand the scheme of the present application, the present application is further described in detail below. The following specific embodiments are only to describe the principles and characteristics of the present application, and the examples are only used to explain the present application, but not to limit the scope of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0033] In the present application, the term "and / or" describes the association relationship of the associated objects, which means that there can be three kinds of relationships, for example, A and / or B, which can represent the following cases: A exists alone, A and B exist together, and B exists alone, wherein A and B can be singular or plural, and the character " / " generally represents an "or" relationship between the associated objects before and after it.

[0034] In the present application, the term "at least one" means one or more, and "multiple" means two or more. "At least one of the following" or similar expressions means any combination of these items, including any combination of single item or multiple items. For example, "at least one of a, b or c", or "at least one of a, b and c", can represent a, b, c, a-b (i.e. a and b), a-c, b-c, or a-b-c, wherein a, b and c can be single or multiple.

[0035] In the present application, the term "micropores" refers to pores with a pore size of <2 nm; the term "mesopores" refers to pores with a pore size in the range of 2-50 nm; and the term "macropores" refers to pores with a pore size of >50 nm.

[0036] In the present application, the term "bisphenol A", also known as BPA, diphenylpropane, p,p'-isopropylidene bisphenol, 2,2-bis-p-phenylpropane or 2,2-bis(4-hydroxyphenyl)propane, is an organic compound with the molecular formula C 15 H 16 O2.

[0037] In the present application, the micropore specific surface area or the total specific surface area of the modified activated carbon can be obtained by a specific surface and porosity analyzer (BET).

[0038] In order to precisely control the pore properties of the activated carbon, in detail, in order to precisely control the proportion of the micropore specific surface area in the total specific surface area of the activated carbon, the present application adopts the following technical solutions:

[0039] In a first aspect, the present application provides a modified activated carbon, comprising an activated carbon base body, wherein the activated carbon base body comprises a plurality of micropores and a plurality of mesopores, and at least part of the micropores are combined with a modifier through a chemical bond; and the modified activated carbon satisfies the following formula 1 and formula 2: T1 < T2 Formula 1, 0.4 ≤ S1 / S2 ≤ 0.6 Formula 2; 0.8 ≤ S3 / S4 ≤ 1 Formula 3.

[0040] Wherein, T1 is the decomposition temperature of the modifier, T2 is the initial decomposition temperature of the activated carbon base body, S1 is the micropore specific surface area of the modified activated carbon, S2 is the micropore specific surface area of the modified activated carbon after being calcined at a temperature greater than T1 and less than T2, S3 is the mesopore specific surface area of the modified activated carbon, and S4 is the mesopore specific surface area of the modified activated carbon after being calcined at a temperature greater than T1 and less than T2.

[0041] It should be noted that T1, T 2、The comparison of S2 and S4 both need to be carried out in an oxygen-containing atmosphere. Exemplarily, T1 and T2 can be obtained by a thermogravimetric analysis (TG) test. T1 corresponds to a temperature value not less than a maximum weight loss rate in a TG curve of the modifier. Further, in order to make the modifier decompose completely, T1 is preferably a temperature value not greater than a maximum decrease amplitude point (the maximum decrease amplitude point: when the weight loss of a substance, the weight data tends to be flat at a certain temperature, and almost no weight loss is observed). For example, in an actual test, 20 mg of the modifier is heated at a rate of 20℃ / min in an air atmosphere. The temperature interval corresponding to the weight reduction of the modifier is observed, and the temperature at which the weight decreases most quickly in the interval is recorded as a temperature value corresponding to the maximum weight loss rate, which is denoted as Q1. The highest temperature in the interval is a temperature at which the weight loss decreases greatly, which is denoted as Q2. T1 is any value between Q1 and Q2. T2 can be understood as a temperature at which the structure of the activated carbon substrate begins to collapse, which corresponds to a temperature value corresponding to the maximum weight loss rate in the TG curve. The purpose of calcining the modified activated carbon at a temperature greater than T1 and less than T2 is to ensure that the structure of the activated carbon substrate does not collapse, and to make the combined modifier decompose by calcination to restore the micropore channels of the activated carbon substrate occupied by the modifier. Therefore, the micropore specific surface area S2 of the modified activated carbon after calcination at a temperature greater than T1 and less than T2 can also be understood as the micropore specific surface area of the activated carbon substrate without the combined modifier. S4 can be understood as the mesopore specific surface area of the activated carbon substrate without the combined modifier.

[0042] Further, in the TG curve of the activated carbon substrate, the temperature interval at which the weight loss is 2-5wt% is denoted as Q3, and Q3 < T2. The temperature greater than T1 and less than T2 is denoted as Q4, and Q4 is any value greater than Q1 and less than or equal to Q3.

[0043] The activated carbon substrate includes a plurality of micropores and a plurality of mesopores, and can also include macropores. Since the specific surface area of the macropores is low, the supported catalyst can be ignored. Therefore, the macropores of the activated carbon substrate are not specifically limited in the present application.

[0044] In the present application, the micropore combined modifier, including the micropore inner surface and / or the micropore outer surface combined modifier, can control the proportion of the micropore specific surface area of the activated carbon in the total specific surface area by the combined modifier. In detail, the modified activated carbon realizes the occupation of the micropore channel by combining the modifier in the micropore channel of the activated carbon matrix (there may be a small amount of modifier occupying the mesopore channel). At this time, the micropore specific surface area of the modified activated carbon is S1, and the mesopore specific surface area is S3. Since the modifier has less effect on the mesopore channel, when the modified activated carbon is used as a carrier to prepare a catalyst, the active phase will be more attached to the mesopore channel of the carrier, which is beneficial to increase the probability of contact between the larger-sized raw material molecules and the active phase, thereby improving the catalytic activity of the catalyst. Secondly, since the decomposition temperature T1 of the above-mentioned modifier is lower than the decomposition temperature T2 of the activated carbon, therefore, the modified activated carbon can be calcined at a temperature greater than T1 and less than T2 after loading the active group according to the needs, so as to restore the pore volume of the micropore channel and the small amount of mesopore channel that may be occupied. At this time, the micropore specific surface area of the modified activated carbon is restored to S2, and the mesopore specific surface area is restored to S4. Since S2 and S4 satisfy formula 2 and formula 3, therefore, the total pore volume and specific surface area of the activated carbon after calcination increase, thereby realizing the precise control of the pore properties of the activated carbon.

[0045] In a preferred embodiment, the modifier is an amino acid. Among them, the amino acid type modifier is a non-hazardous product, so the modification process has the advantages of safety and environmental protection.

[0046] The above-mentioned chemical bond can be understood as being combined by the interaction between chemical functional groups. As for the type of chemical bond, the present application does not make special limitations.

[0047] In a preferred embodiment, the modifier contains one or more of amidine groups, benzyl groups, and thiol functional groups.

[0048] The above-mentioned amidine groups, benzyl groups, and thiol functional groups can chemically react with the activated carbon matrix, thereby forming a tightly combined chemical bond, which will not cause the content of adsorbed organic matter to change after water washing, and can prevent the organic matter from falling off when the modified activated carbon encounters an aqueous solution.

[0049] In a specific embodiment, the modifier is one or more of arginine, phenylalanine, and methionine.

[0050] In a preferred embodiment, the mesopore specific surface area of the modified activated carbon accounts for more than 50% of the total specific surface area.

[0051] And / or, the micropore specific surface area of the modified activated carbon accounts for less than 50% of the total specific surface area.

[0052] In the formula, the mesopore specific surface area accounts for more than 50% of the total specific surface area, which can ensure that the active phase is more attached to the mesopore channel surface of the carrier, thereby increasing the probability of contact between the larger raw material molecules and the active phase, and further improving the catalytic activity of the catalyst; and the micropore specific surface area accounts for less than 50% of the total specific surface area, which can enable the active phase to be less attached to the micropore channel surface of the activated carbon carrier.

[0053] In a preferred embodiment, T2-T1≥50℃. The more obvious the gap between T2 and T1 is, the more it can ensure that the modifier is removed while the basic pore structure of the activated carbon matrix is not destroyed.

[0054] In a specific embodiment, T1 is selected from any value in the range of 200℃ to 400℃.

[0055] In a second aspect, the application provides a preparation method as described above, comprising the following steps:

[0056] The mixed system containing the activated carbon matrix, the modifier and the solvent is stirred at 20-80℃ for 0.5-3h, and then filtered and dried to obtain the product; wherein the pH of the mixed system is 6-10.

[0057] The pH of the mixed system is limited in the above method, which can ensure that there is no adverse effect on the basic structure of the activated carbon matrix. If the pH is too high or too low, it may etch the basic skeleton of the micropores and mesopores of the activated carbon matrix, thereby affecting the total specific surface area of the activated carbon matrix.

[0058] In the preparation method provided by the application, the solvent of the mixed system is not specifically limited by the application, as long as it can play a dispersing role and does not react with the modifier and the activated carbon matrix, for example, deionized water.

[0059] In a third aspect, the application provides a catalyst comprising a carrier and an active ingredient loaded on the carrier, wherein the carrier is the modified activated carbon described above; and the active ingredient is at least partially loaded in the mesopores of the modified activated carbon.

[0060] And / or, the active ingredient comprises ruthenium trichloride.

[0061] It can be understood that, since the micropores of the modified activated carbon are occupied by the modifier, the active ingredient can only be mainly loaded in the mesopores or macropores of the modified activated carbon.

[0062] In a fourth aspect, the application provides a catalyst prepared by a method comprising the following steps:

[0063] The active ingredient is loaded in the mesopores of the modified activated carbon described above by impregnation treatment to obtain an intermediate; and the intermediate is calcined at a temperature greater than T1 and less than T2 to remove the modifier, thereby obtaining the catalyst.

[0064] It can be understood that the above method can decompose the modifier of the modified activated carbon, i.e. restore the micropore channels occupied by the modifier, and therefore the catalyst has the feature that the active component is mainly loaded in the mesopore channels of the non-micropore channels of the activated carbon matrix.

[0065] In a fifth aspect, the application provides a method for catalytic hydrogenation of a benzene ring-containing chemical monomer, and the catalyst comprises any catalyst provided in the third aspect or the fourth aspect.

[0066] In a specific embodiment, the benzene ring-containing chemical monomer is bisphenol A, and the application further provides a method for preparing hydrogenated bisphenol A by catalytic hydrogenation of bisphenol A, and any catalyst provided in the third aspect or the fourth aspect is used.

[0067] It can be understood that, as the catalyst in the third aspect is used, the method comprises: calcining the catalyst at a temperature greater than T1 and less than T2, and then using the catalyst after removal of the modifier for the catalytic hydrogenation reaction of bisphenol A.

[0068] The application is further described below in combination with specific embodiments:

[0069] In the following experiments, two types of activated carbon matrix are used, both of which are provided by Fushun Catalyst Factory, one of which is activated carbon A0 with a thermal weight loss of 2.5 wt% at 400°C, and the other is activated carbon A01 with a thermal weight loss of 2.5 wt% at 450°C.

[0070] The decomposition temperature of arginine is 250-350°C, the decomposition temperature of methionine is 258-269°C, and the decomposition temperature of phenylalanine is 326-365°C.

[0071] Example 1

[0072] This example provides a modified activated carbon, which comprises an activated carbon matrix, and the activated carbon matrix comprises a plurality of micropores and a plurality of mesopores, and at least part of the micropores are combined with arginine.

[0073] The preparation method of the modified activated carbon comprises the following steps:

[0074] 10 g of activated carbon matrix A0 is weighed and added to 100 g of deionized water, and after stirring to uniformity, 0.8 g of arginine is added, the pH of the mixed system is 10, and after constant temperature at 45°C for 3 h under stirring, the system is filtered, and the solid component is dried at 80-120°C to obtain the modified activated carbon A1.

[0075] Example 1-1

[0076] This example provides a catalyst, and the preparation method thereof comprises the following steps:

[0077] The activated carbon impregnated with ruthenium trichloride was obtained by impregnation and drying with the modified activated carbon A1 as the carrier and ruthenium trichloride aqueous solution as the impregnation liquid. The activated carbon impregnated with ruthenium trichloride was calcined at 350°C for 6h under air atmosphere to obtain the catalyst B1 (ruthenium trichloride content 0.3wt%).

[0078] Example 2

[0079] The present example provides a modified activated carbon. The modified activated carbon comprises an activated carbon matrix, wherein the activated carbon matrix comprises a plurality of micropores and a plurality of mesopores, and at least part of the micropores are combined with arginine and phenylalanine.

[0080] The preparation method of the modified activated carbon comprises the following steps:

[0081] 10g of the activated carbon matrix A0 was added into 250g of deionized water, and then 0.4g of arginine and 0.2g of phenylalanine were added after stirring to make the pH of the mixed system 8. After constant temperature at 20°C for 0.5h under stirring, the system was filtered. After drying, the solid component was obtained to obtain the modified activated carbon A2.

[0082] Example 2-1

[0083] The present example provides a catalyst. The preparation method of the catalyst comprises the following steps:

[0084] The activated carbon impregnated with ruthenium trichloride was obtained by impregnation and drying with the modified activated carbon A2 as the carrier and ruthenium trichloride aqueous solution as the impregnation liquid. The activated carbon impregnated with ruthenium trichloride was calcined at 340°C for 3h under air atmosphere to obtain the catalyst B2 (ruthenium trichloride content 0.3wt%).

[0085] Example 3

[0086] The present example provides a modified activated carbon. The modified activated carbon comprises an activated carbon matrix, wherein the activated carbon matrix comprises a plurality of micropores and a plurality of mesopores, and at least part of the micropore channels are combined with methionine.

[0087] The preparation method of the modified activated carbon comprises the following steps:

[0088] 10g of the activated carbon matrix A0 was added into 100g of deionized water, and then 50g of methionine aqueous solution (containing 0.6g of methionine in the solution) was added after stirring to make the pH of the mixed system 6. After constant temperature at 80°C for 2h under stirring, the system was filtered. After drying, the solid component was obtained to obtain the modified activated carbon A3.

[0089] Example 3-1

[0090] The present example provides a catalyst. The preparation method of the catalyst comprises the following steps:

[0091] The activated carbon impregnated with ruthenium trichloride was obtained by impregnation and drying with 2 volumes of impregnation, using the modified activated carbon A4 as the carrier and ruthenium trichloride aqueous solution as the impregnation liquid. The activated carbon impregnated with ruthenium trichloride was calcined at 330°C for 5h under air atmosphere to obtain the catalyst B4 (ruthenium trichloride content 0.3wt%).

[0092] Example 4

[0093] The modified activated carbon provided in this example includes an activated carbon matrix, which includes a plurality of micropores and a plurality of mesopores, and at least part of the micropores are combined with arginine and methionine.

[0094] The preparation method of the modified activated carbon provided in the above example includes the following steps:

[0095] 10g of the activated carbon matrix A0 was added into 150g of deionized water, and then 80g of the organic aqueous solution (containing 0.5g of arginine and 0.2g of methionine) was added after uniform stirring, and the pH of the mixed system was 8. After constant temperature at 30°C for 2.5h under stirring, the system was filtered. After drying, the solid component was obtained to obtain the modified activated carbon A4.

[0096] Example 4-1

[0097] The preparation method of the catalyst provided in this example includes the following steps:

[0098] The activated carbon impregnated with ruthenium trichloride was obtained by impregnation and drying with 2 volumes of impregnation, using the modified activated carbon A4 as the carrier and ruthenium trichloride aqueous solution as the impregnation liquid. The activated carbon impregnated with ruthenium trichloride was calcined at 330°C for 5h under air atmosphere to obtain the catalyst B4 (ruthenium trichloride content 0.3wt%).

[0099] Example 5

[0100] The modified activated carbon provided in this example includes an activated carbon matrix, which includes a plurality of micropores and a plurality of mesopores, and at least part of the micropores are combined with arginine and methionine.

[0101] 10g of the activated carbon matrix A01 was added into 150g of deionized water, and then 80g of the organic aqueous solution (containing 0.5g of arginine and 0.2g of methionine) was added after uniform stirring, and the pH of the mixed system was 8. After constant temperature at 30°C for 2.5h under stirring, the system was filtered. After drying, the solid component was obtained to obtain the modified activated carbon A5.

[0102] Comparative Example 1

[0103] The preparation method of the modified activated carbon and the catalyst provided in this example includes the following steps:

[0104] Take 10 g of activated carbon matrix into 100 g of deionized water, stir until uniform, then add 0.6 g of arginine, the pH of the mixed system is 10. After constant temperature at 45 °C for 3 h under stirring, the system is filtered. After drying, the solid component is obtained to obtain modified activated carbon C1.

[0105] Use equal volume impregnation method, take modified activated carbon C1 as carrier, take ruthenium trichloride aqueous solution as impregnation liquid, through impregnation and drying to obtain activated carbon impregnated with ruthenium trichloride. The activated carbon impregnated with ruthenium trichloride is calcined at 300 °C for 6 h in air atmosphere to obtain catalyst D1 (ruthenium trichloride content 0.3 wt%).

[0106] Comparative Example 2

[0107] This example provides a modified activated carbon and catalyst, the preparation method comprises the following steps:

[0108] Take 10 g of activated carbon matrix and mix with 120 mL of water, ultrasonic for 30 min, add 30 mL of 1% glucose aqueous solution, the pH of the mixed system is 6, stir for 6 h, filter, dry at 110 °C for 8 h. The dried activated carbon is calcined at 800 °C for 60 min under nitrogen protection to obtain modified activated carbon C2.

[0109] Use equal volume impregnation method, take modified activated carbon C2 as carrier, take ruthenium trichloride aqueous solution as impregnation liquid, through impregnation and drying to obtain activated carbon impregnated with ruthenium trichloride. The activated carbon impregnated with ruthenium trichloride is calcined at 300 °C for 6 h in air atmosphere to obtain catalyst D2 (ruthenium trichloride content 0.3 wt%).

[0110] Comparative Example 3

[0111] This example provides a modified activated carbon and catalyst, the preparation method comprises the following steps:

[0112] Take 6 g of glycine and add distilled water to 300 g, after dissolving, add 9 g of activated carbon matrix, mix uniformly, the pH of the mixed system is 6. Stir at 80 °C constant temperature for 8 h at 100 r / min, take out and stand for 4 h, then filter, repeatedly wash with distilled water for several times until neutral, dry at 105 °C for 12 h to obtain modified activated carbon C3.

[0113] Use equal volume impregnation method, take modified activated carbon C3 as carrier, take ruthenium trichloride aqueous solution as impregnation liquid, through impregnation and drying to obtain activated carbon impregnated with ruthenium trichloride. The activated carbon impregnated with ruthenium trichloride is calcined at 300 °C for 6 h in air atmosphere to obtain catalyst D3 (ruthenium trichloride content 0.3 wt%).

[0114] Comparative Example 4

[0115] The present example provides a catalyst, and a preparation method thereof, comprising the following steps:

[0116] The activated carbon AO was impregnated with an equal volume of a ruthenium trichloride aqueous solution as the impregnation liquid, and then dried to obtain activated carbon impregnated with ruthenium trichloride. The activated carbon impregnated with ruthenium trichloride was calcined at 300°C for 6h in an air atmosphere to obtain catalyst D4 (ruthenium trichloride content 0.3wt%).

[0117] Test Example 1

[0118] The modified activated carbon was characterized by UV-Vis spectroscopy to show that the modification of the activated carbon was successful and that the modified activated carbon after washing did not change the content of the organic matter: As shown in FIG. 1, 0.8g arginine was dissolved in 100g water at the beginning of preparation, and there was a clear UV-Vis absorption spectrum. After adding 10g activated carbon matrix under stirring conditions and stirring at 45°C for 3h, the UV-Vis absorption spectrum of the aqueous solution showed a significant decrease in absorbance, indicating that the arginine in the solution had combined with the activated carbon matrix to form modified activated carbon A1 successfully modified with arginine. The modified activated carbon A1 was then added to 100g water, stirred and washed, and the washed solution was filtered. The UV-Vis absorption spectrum of the washed solution showed no significant absorption spectrum, further indicating that the arginine had chemically reacted with the activated carbon to form a stable arginine-activated carbon structure. Thus, the modified activated carbon A1 can be used for subsequent load modification treatment in an aqueous solution environment. The same test was performed on the modified activated carbon of other examples, and the UV-Vis absorption spectrum of the washed solution showed no significant absorption spectrum. This result indicates that the agents of each example can be stably combined with activated carbon through chemical bonds and can be used for subsequent load modification treatment in an aqueous solution environment.

[0119] Thermogravimetric analysis was used to characterize the calcination at a temperature higher than the decomposition temperature of the modified organic matter and lower than the temperature at which the activated carbon significantly loses weight in an air atmosphere to prove that calcination can remove the modifier: Thermogravimetric analysis was performed on activated carbon AO and modified activated carbon A1 in an air atmosphere. The characterization conditions were an air atmosphere and a heat treatment temperature of 120°C to 500°C. As shown in FIG. 2, the weight loss rate of activated carbon AO at 400°C was 2.5%, and the modified activated carbon A1 had a significant weight loss process starting at 200°C compared to A0, indicating that the modified arginine can gradually decompose in an air atmosphere at 200°C to 400°C. This can prove that calcination at a temperature higher than the decomposition temperature of the modified organic matter and lower than the temperature at which the activated carbon significantly loses weight in an air atmosphere can remove the organic matter in the organic matter modified activated carbon, thereby restoring the microporous channels of the activated carbon blocked during the modification process.

[0120] Test Example 2

[0121] The modified activated carbons A1-A5, C1, C3 were calcined at 350°C for 6h under air atmosphere to obtain activated carbons A1'-A5', C1' and C3'. The activated carbons A0, A1-A5, A1'-A5', C1, C2, C3, C1' and C3' were characterized by nitrogen physical adsorption, and the characterization results are shown in Table 1. The total specific surface area was calculated by BET method. In order to make the BET equation hold, at least 3 points in the range of 0.01-0.30 of p / p0 were selected, and the BET specific surface area was obtained under the condition that the C value satisfying the BET equation was greater than 0. The mesopore and micropore specific surface areas were calculated by t-Plot method.

[0122] Table 1 Physical adsorption characterization results of activated carbons

[0123] From the data in Table 1, it can be seen that the micropore specific surface area of A1, A2, A3 and A4 is obviously reduced relative to A0. Specifically, the micropore specific surface area of A0 accounts for 60% of the total specific surface area, and the micropore specific surface area of A1, A2, A3 and A4 accounts for 45%-48% of the total specific surface area. The micropore specific surface area of A5 is also obviously reduced relative to A01. Specifically, the micropore specific surface area of A01 accounts for 92% of the total specific surface area, and the micropore specific surface area of A5 accounts for 45% of the total specific surface area. Although the micropore specific surface area of C1 is reduced, the micropore specific surface area of C1 accounts for 58% of the total specific surface area, which is not much different from that of A0. C2 uses sugar as a modifier, and sugar expands in volume when heat-treated under inert atmosphere. Therefore, the micropore and mesopore specific surface areas of C2 are both obviously reduced. C3 is an activated carbon treated by glycine. Since glycine cannot be combined with activated carbon by chemical bonds, the glycine is washed away by water and does not successfully occupy the micropores of the activated carbon, and the total specific surface area and the micropore specific surface area of C3 change little. The above results show that the modified activated carbons of the embodiments of the present application can better occupy the micropores of the activated carbon, can significantly reduce the micropore specific surface area, and have little effect on the mesopore specific surface area, which is more conducive to the attachment of active metals to the mesopore positions of the activated carbon during impregnation. Furthermore, by comparing the modified activated carbons A1-A4 and A1'-A4', A5 and A5', it can be seen that the micropore specific surface area of the modified activated carbons of the embodiments of the present application can be well recovered by heat treatment, indicating that the modified activated carbons of the present application as a carrier can make the active phase attach to the mesopore channels, and then the original micropore channels can be recovered by heat treatment.

[0124] Test Example 3

[0125] The catalysts B1, B2, B3, B4, D1, D2, D3, D4 were pre-reduced in a tube furnace at a reduction temperature of 120°C for 2h, and then the catalytic activity of each catalyst for the catalytic hydrogenation of bisphenol A to prepare hydrogenated bisphenol A was investigated using a kettle reactor. The specific evaluation process conditions were as follows: isopropyl alcohol was used as a solvent to prepare a bisphenol A solution with a mass content of 20%, the catalyst dosage was 2wt%, the reaction temperature was 170°C, the reaction pressure was 4.0MPa, and the reaction time was 4h. The conversion rate of bisphenol A was investigated under the process conditions, and the evaluation results are shown in Table 2.

[0126] Table 2 evaluation results

[0127] As can be seen from the data in Table 2, the catalyst prepared in the application can further improve the conversion rate of bisphenol A when used for the catalytic hydrogenation of bisphenol A to prepare hydrogenated bisphenol A, which means that the catalyst of the application is more conducive to the hydrogenation saturation process of molecules such as bisphenol A which are not easy to enter the microporous structure reaction due to their relatively large molecular size.

[0128] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the application, and not to limit them; although the application has been described in detail with reference to the foregoing examples, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing examples, or make equivalent substitutions for part of the technical features; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the application.

Claims

1. A modified activated carbon, characterized in that It includes an activated carbon matrix, and the activated carbon matrix includes a number of micropores and a number of mesopores. Among them, at least part of the micropores are chemically bonded with a modifier; and the modified activated carbon satisfies the following formulas 1 to 3: T1 < T2 (Formula 1), 0.4 ≤ S1 / S2 ≤ 0.6 (Formula 2), 0.8 ≤ S3 / S4 ≤ 1 (Formula 3); Among them, T1 is the decomposition temperature of the modifier, T2 is the initial decomposition temperature of the activated carbon matrix, S1 is the micropore specific surface area of the modified activated carbon, S2 is the micropore specific surface area of the modified activated carbon after calcination at a temperature greater than T1 and less than T2, S3 is the mesopore specific surface area of the modified activated carbon, and S4 is the mesopore specific surface area of the modified activated carbon after calcination at a temperature greater than T1 and less than T2.

2. The modified activated carbon according to claim 1, characterized in that The modifier is an amino acid; And / or, the modifier contains one or several of amidino, benzyl, and mercapto functional groups.

3. The modified activated carbon according to claim 2, characterized in that The modifier is one or several of arginine, phenylalanine, and methionine.

4. The modified activated carbon according to any one of claims 1 to 3, characterized in that The mesopore specific surface area of the modified activated carbon accounts for more than 50% of the total specific surface area; And / or, the micropore specific surface area of the modified activated carbon accounts for less than 50% of the total specific surface area.

5. The modified activated carbon according to any one of claims 1 to 3, characterized in that T2 - Tl ≥ 50 °C.

6. A method for preparing modified activated carbon according to any one of claims 1 to 5, characterized in that: It includes the following steps: A mixed system containing an activated carbon matrix, a modifier, and a solvent is stirred at 20 - 80 °C for 0.5 - 3 h, and then obtained after filtration and drying; among them, the pH of the mixed system is 6 - 10.

7. A catalyst comprising a carrier and an active ingredient supported on the carrier, characterized in that: The carrier is the modified activated carbon according to any one of claims 1 - 5; at least part of the active ingredient is loaded in the mesopores of the modified activated carbon; And / or, the active ingredient includes ruthenium trichloride.

8. A catalyst, characterized in that It is prepared by a method including the following process: Through impregnation treatment, the active ingredient is loaded in the mesopores of the modified activated carbon according to any one of claims 1 - 5 to obtain an intermediate; the intermediate is calcined at a temperature greater than T1 and less than T2 to remove the modifier, and the catalyst is obtained.

9. A method for catalytic hydrogenation of chemical monomers containing benzene rings, characterized in that: The catalyst includes the catalyst according to any one of claims 7 - 8.

10. The catalytic hydrogenation method according to claim 9, characterized in that: The chemical monomer containing a benzene ring is bisphenol A.

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