An alloy catalyst, a method for preparing the same, and an application thereof

Abstract

This invention relates to the field of fine chemical technology, and discloses an alloy catalyst, its preparation method, and its application. The preparation method of the alloy catalyst of this invention includes: S1, dispersing a copper source, a platinum source, and an anchoring agent in a solvent, and then adding a reducing agent; S2, dispersing the pretreated support in the solution obtained in step S1 for loading; S3, drying the loaded support obtained in step S2 to obtain the alloy catalyst; the anchoring agent is used to anchor copper and platinum onto the support. The alloy catalyst of this invention uses a copper source, a platinum source, and an anchoring agent as raw materials. The anchoring agent loads copper and platinum metal particles onto the support, effectively preventing the detachment and loss of copper and platinum metals. The alloy catalyst is used to catalyze the synthesis of the antioxidant 6PPD, effectively inhibiting the ketone-to-alcohol side reaction and improving catalytic efficiency.

Description

Technical Field

[0001] This invention relates to the field of fine chemical technology, and in particular to an alloy catalyst, its preparation method, and its application. Background Technology

[0002] 6PPD is a rubber antioxidant, also known as antioxidant 4020, with the chemical name N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine. It is a low-toxicity, solvent-resistant, and highly efficient p-phenylenediamine antioxidant. In natural and synthetic rubber, it has good resistance to ozone and flexural aging, heat and oxidation, and corrosion from metals such as copper and manganese. Therefore, it is widely used in tires, cables, and other industrial rubber products.

[0003] The synthesis of 6PPD includes reductive amination, Schiff base hydrogenation, phenol-amine condensation, hydroxylamine reductive alkylation, and quinone imine condensation. Reductive amination uses 4-aminodiphenylamine and methyl isobutyl ketone as raw materials, and under specific temperature, pressure, and catalyst conditions, hydrogen is used to reduce and amination to obtain the target product, 6PPD. In China, the reductive amination method for 6PPD generally uses copper-based catalysts containing only metallic copper. While copper-based catalysts are inexpensive and facilitate continuous fixed-bed production, their poor selectivity and severe side reactions, such as ketone-to-alcohol conversion, limit the product's application range. Therefore, developing a highly efficient and clean noble metal catalyst for the efficient synthesis of 6PPD is of great significance. Summary of the Invention

[0004] This invention addresses the technical problems of poor selectivity and severe ketone-to-alcohol conversion side reactions in the existing reductive amination method for synthesizing 6PPD using copper-containing catalysts. It provides an alloy catalyst, its preparation method, and its applications. The alloy catalyst of this invention uses copper, platinum, and an anchoring agent as raw materials. The anchoring agent effectively supports copper and platinum metal particles on a carrier, preventing the detachment and loss of copper and platinum metals. The alloy catalyst prepared by this invention, when used in the catalytic synthesis of the antioxidant 6PPD, effectively suppresses the ketone-to-alcohol conversion side reaction and improves catalytic efficiency.

[0005] One objective of this invention is to provide a method for preparing an alloy catalyst, comprising:

[0006] S1. Disperse the copper source, platinum source and anchoring agent in a solvent by stirring, and then add the reducing agent;

[0007] S2. Disperse the pretreated carrier into the solution obtained in step S1 for loading;

[0008] S3. The support loaded in step S2 is dried to obtain the alloy catalyst.

[0009] The anchoring agent is used to anchor copper and platinum to the carrier.

[0010] A copper source, a platinum source, and an anchoring agent are uniformly dispersed in a solvent, and then a reducing agent is added. After reduction, the copper and platinum sources exist in elemental form, or in a combination of elemental and free states. Some copper and / or platinum are linked to the carrier through the anchoring agent, which fixes the copper and / or platinum onto the carrier. For example, copper nitrate and chloroplatinic acid, after reduction with sodium borohydride, exist in both elemental and free states as metallic particles, and are linked to the activated carbon carrier through thiol groups.

[0011] When copper and platinum are used as hydrogenation catalysts, some copper atoms enter the platinum lattice, causing a change in the catalyst's electronic structure. This change in electronic structure may enhance the catalyst's adsorption and activation capacity for reactants, thereby effectively improving the catalyst's catalytic performance and efficiency.

[0012] According to a preferred embodiment of the present invention, the pretreatment step of the carrier is as follows: the carrier is first acid-washed, then treated with ammonium carbonate solution, and then washed with deionized water until neutral;

[0013] Preferably, the pickling, ammonium carbonate solution treatment, and deionized water washing are all followed by drying; that is, the pretreatment steps of the carrier are: first pickling, then drying; then ammonium carbonate solution treatment, then drying; and finally washing with deionized water until neutral, then drying.

[0014] Ammonium carbonate, as a nitrogen source, increases the nitrogen doping content in the catalyst, thereby enhancing the catalytic hydrogenation reaction.

[0015] According to a preferred embodiment of the present invention, the copper source is at least one of copper chloride, copper nitrate, copper acetate, and copper sulfate; from the perspective of raw material price and catalyst preparation effect, copper nitrate is preferred.

[0016] And / or, the platinum source is at least one selected from chloroplatinic acid, chloroplatinate, platinum nitrate, and platinum sulfate; preferably chloroplatinic acid;

[0017] And / or, the anchoring agent is at least one of mercaptosuccinic acid, mercaptoethanol, mercaptoacetic acid, thiophenol, cysteine, preferably one of mercaptosuccinic acid, mercaptoethanol and mercaptoacetic acid, more preferably mercaptosuccinic acid;

[0018] And / or, the reducing agent is at least one of sodium borohydride, potassium borohydride, and ascorbic acid, preferably sodium borohydride;

[0019] And / or, the carrier is at least one of activated carbon, carbon nanotubes, and graphene, preferably at least one of activated carbon and carbon nanotubes.

[0020] According to a preferred embodiment of the present invention, the molar ratio of the copper source, platinum source and anchoring agent is (0.5-2):(0.5-4):(2-10), preferably 1:3:4;

[0021] And / or, the amount of the reducing agent is 2-6 times the total amount of the copper source and the platinum source;

[0022] And / or, the solvent content is 5-300 mL;

[0023] And / or, the weight of the carrier is 1-200g, and the weight of the carrier is 10-100 times the sum of the weights of the copper source and the platinum source.

[0024] According to a preferred embodiment of the present invention, the acidic solution used for pickling is at least one selected from sulfuric acid, hydrochloric acid, nitric acid, and phosphoric acid;

[0025] And / or, the ammonium carbonate solution has a concentration of 10wt% to 28wt%.

[0026] The activated carbon modified with ammonium carbonate in this invention enhances the active sites, increases the molecular transport rate, and strengthens the adsorption and desorption capacity of hydrogen molecules.

[0027] The pretreatment steps for activated carbon are as follows: 1) Wash the activated carbon with deionized water, soak it in a 30% hydrochloric acid solution for 10-14 hours, wash it again, and place the washed activated carbon in a drying oven at 120℃-150℃ for 4-8 hours, then place it in a desiccator; 2) Soak and wash it with a 10-28wt% ammonium carbonate solution at 10℃-30℃ for 12-20 hours; 3) Filter the soaking solution, take out the soaked activated carbon, put it in a drying oven at 120℃-150℃ for 6-8 hours; 4) Wash the soaked and dried activated carbon with deionized water until neutral, put it in a drying oven at 120℃-150℃ for 10-12 hours, and the pretreated activated carbon is ready.

[0028] The preparation method of the alloy catalyst includes the following steps: 1) Add chloroplatinic acid, copper nitrate and mercaptosuccinic acid (MSA) to DI, and stir until fully dissolved and homogeneous; 2) Add sodium borohydride, stir at a rate of 2-20 mL / min for 30 min to obtain solution A; 3) Disperse the pretreated support in solution A, stir at room temperature for 2-6 h for loading, wash with deionized water and dry to obtain the sample CuPt / C loaded with metal.

[0029] Preferably, the molar ratio of chloroplatinic acid, copper nitrate, and mercaptosuccinic acid is (0.5-2):(0.5-4):(2-10). Preferably, the amount of sodium borohydride is 2-6 times the total amount of copper and platinum sources, preferably 4 times.

[0030] The second objective of this invention is to provide an alloy catalyst prepared by the above-mentioned method.

[0031] The third objective of this invention is to provide an alloy catalyst for the reaction of 4-aminodiphenylamine with methyl isobutyl ketone to prepare the antioxidant 6PPD.

[0032] According to a preferred embodiment of the present invention, the molar ratio of 4-aminodiphenylamine to methyl isobutyl ketone is 1:3 to 6; the reaction conditions include: temperature 60°C to 150°C, preferably 70°C to 100°C; reaction pressure 0.6 to 3.0 MPa, preferably 0.8 to 1.5 MPa; and reaction time 1 to 2 hours.

[0033] According to a preferred embodiment of the present invention, the content of the alloy catalyst is 0.2-20 wt% of 4-aminodiphenylamine, preferably 0.3-10 wt%, and more preferably 1.5-5 wt%.

[0034] The reaction of 4-aminodiphenylamine with methyl isobutyl ketone in this invention is carried out in a fixed bed or a reaction vessel; after the reaction, the conversion rate of 4-aminodiphenylamine is 89.5% to 99.8%, the selectivity of 6PPD is 87% to 99.5%, and the ketone-to-alcohol ratio is 85 / 15 to 99 / 1.

[0035] The beneficial effects of the present invention are as follows: The alloy catalyst of the present invention uses copper source, platinum source and anchoring agent as raw materials. The copper and platinum metal particles are loaded on the carrier by the anchoring agent, which can effectively prevent the copper and platinum metals from falling off and being lost.

[0036] The alloy catalyst prepared in this invention is used for the catalytic synthesis of the antioxidant 6PPD, effectively suppressing the side reaction of ketone-to-alcohol conversion and improving catalytic efficiency. By controlling the alloy composition, the proportion of precious metals is reduced while ensuring the preparation of a highly active and selective catalyst, thereby lowering the catalytic production cost. Detailed Implementation

[0037] The present invention will be further described below with reference to specific embodiments, but this does not constitute any limitation on the present invention.

[0038] In the following embodiments, the present invention uses pretreated activated carbon as a support to prepare a catalyst supported on alloy nanoparticles, and controls the ratio of copper to platinum to utilize the synergistic effect between the metals. Copper and platinum are excellent hydrogenation catalysts. When copper atoms enter the platinum lattice, it causes a change in the electronic structure of the catalyst itself. This change in electronic structure may enhance the catalyst's adsorption and activation ability for reactants, thereby improving catalytic performance and efficiency. In the preparation of the antioxidant 6PPD, it increases the conversion rate of 4-aminodiphenylamine, improves the selectivity of 6PPD, and inhibits the side reaction of ketone to alcohol conversion.

[0039] The conversion rate of 4-aminodiphenylamine is calculated as: the amount of 4-aminodiphenylamine consumed in the reaction / the total amount of 4-aminodiphenylamine in the raw materials before the reaction. The amount of 4-aminodiphenylamine consumed in the reaction is calculated by subtracting the amount of 4-aminodiphenylamine remaining in the reaction solution after the reaction from the total amount of 4-aminodiphenylamine in the raw materials before the reaction.

[0040] The selection method for 6PPD is: actual yield of 6PPD in the reactor liquid / (theoretical yield of 6PPD and conversion rate of 4-aminodiphenylamine).

[0041] The ketone-to-alcohol ratio is calculated as the ratio of the mass of methyl isobutyl ketone to the mass of 4-methyl-2-pentanol in the distillate.

[0042] The amount of 4-aminodiphenylamine remaining in the reaction vessel liquid, the actual yield of 6PPD in the reaction vessel liquid, the mass of methyl isobutyl ketone in the distillate, and the mass of 4-methyl-2-pentanol were analyzed by chromatography.

[0043]

Preparation Example 1

[0044] Activated carbon pretreatment steps

[0045] (1) Wash the activated carbon with deionized water, soak it in a 30% hydrochloric acid solution for 10-14 hours, wash it again, place the washed activated carbon in a drying oven at 120℃-150℃ for 4-8 hours, and then place it in a desiccator.

[0046] (2) Soak and wash with 10wt% to 28wt% ammonium carbonate solution at 10℃ to 30℃ for 12h to 20h;

[0047] (3) Filter the soaking solution, take out the soaked activated carbon, put it into a drying oven, dry at 120℃~150℃, and dry for 6h~8h.

[0048] (4) Wash the soaked and dried activated carbon with deionized water until it is neutral, put it in a drying oven, dry at 120℃~150℃ for 10h~12h, and the pretreated activated carbon 1.

[0049]

Preparation Example 2

[0050] The only difference from Preparation Example 1 is that “10wt% to 28wt% ammonium carbonate in step (2)” is replaced with “10wt% to 28wt% ammonium bicarbonate”, and the pretreated activated carbon 2 is prepared.

[0051]

Example 1

[0052] Preparation of CuPt / C catalysts

[0053] (1) Weigh 5.8g (10mmol) of chloroplatinic acid, 2.9g of copper nitrate (10mmol) and 3.0g of mercaptosuccinic acid (MSA, 20mmol), with the ratio of chloroplatinic acid to copper nitrate being 1:1. Add them to 200mL of deionized water (DI), dissolve and stir thoroughly to obtain solution A.

[0054] (2) Add 200 mL of sodium borohydride solution (containing 3 g (80 mmol) sodium borohydride) to solution A, stir at a rate of 20 mL / min for 30 min to obtain solution B.

[0055] (3) Disperse 100g of activated carbon 1 obtained in Preparation Example 1 into solution B, stir at room temperature for 2-6h for loading, wash with deionized water and dry to obtain CuPt / C sample 1 loaded with metal.

[0056]

Example 2

[0057] The only difference from Example 1 is that "5.8g (10mmol) of chloroplatinic acid" was replaced with 11.6g (20mmol) of chloroplatinic acid to obtain metal-loaded CuPt / C sample 2.

[0058]

Example 3

[0059] The only difference from Example 1 is that "5.8g (10mmol) of chloroplatinic acid" was replaced with 17.4g of chloroplatinic acid (30mmol) to obtain the metal-loaded CuPt / C sample 3.

[0060]

Example 4

[0061] The only difference from Example 1 is that "5.8g (10mmol) of chloroplatinic acid" was replaced with 23.2g of chloroplatinic acid (40mmol) to obtain the metal-loaded CuPt / C sample 4.

[0062]

Example 5

[0063] The only difference from Example 1 is that "5.8g (10mmol) of chloroplatinic acid" was replaced with 29g of chloroplatinic acid (50mmol) to obtain the metal-loaded CuPt / C sample 5.

[0064]

Example 6

[0065] The only difference from Example 3 is that "17.4g chloroplatinic acid (30mmol)" was replaced with 9.57g platinum nitrate (30mmol) to obtain the metal-loaded CuPt / C sample 6.

[0066]

Example 7

[0067] The only difference from Example 3 is that "2.9g copper nitrate (10mmol)" was replaced with 2.5g copper sulfate pentahydrate (10mmol) to obtain the metal-loaded CuPt / C sample 7.

[0068]

Example 8

[0069] The only difference from Example 3 is that "3.0g mercaptosuccinic acid (20mmol)" was replaced with 2.42g cysteine ​​(20mmol) to obtain the metal-loaded CuPt / C sample 8.

[0070]

Example 9

[0071] The only difference from Example 3 is that "10g activated carbon 1" is replaced with 10g graphene support to obtain CuPt / C sample 9 loaded with metal.

[0072]

Example 10

[0073] The only difference from Example 3 is that “10g activated carbon 1” is replaced with 10g of activated carbon 2 prepared in Preparation Example 2, resulting in a CuPt / C sample 10 loaded with metal.

[0074]

Application Example 1

[0075] 1 mmol (0.06 g) of CuPt / C sample 1 prepared in Example 1 was placed in a high-pressure reactor. Methyl isobutyl ketone and 4-aminodiphenylamine were added. The reaction temperature was 110 °C, the pressure was 1.2 MPa, and the molar ratio of methyl isobutyl ketone to p-aminodiphenylamine was 5:1 (p-aminodiphenylamine was 18.4 g, and methyl isobutyl ketone was 36.8 g) to prepare the antioxidant 6PPD. The reaction time was 2 h. After the reaction, the liquid in the reactor was distilled under reduced pressure at 140 °C, 20 kPa, and for 3 h. The distillate (mainly methyl isobutyl ketone) was recovered and reused. Chromatographic analysis of the reactor liquid showed that the conversion rate of 4-aminodiphenylamine was 89.5%, the selectivity of 6PPD was 87.5%, and the ketone-to-alcohol ratio was 85 / 15.

[0076]

Application Example 2

[0077] The only difference from Application Example 1 is that “1mmol CuPt / C sample 1” is replaced with 2mmol CuPt / C sample 1.

[0078] Chromatographic analysis of the reaction solution showed that the conversion rate of 4-aminodiphenylamine was 94.5%, the selectivity was 95.5%, and the ketone-to-alcohol ratio was 88 / 12.

[0079]

Application Example 3

[0080] The only difference from Application Example 1 is that “1mmol CuPt / C sample 1” is replaced with 5mmol CuPt / C sample 1.

[0081] Chromatographic analysis of the reaction solution showed that the conversion rate of 4-aminodiphenylamine was 97.5%, the selectivity of 6PPD was 96.5%, and the ketone-to-alcohol ratio was 92 / 8.

[0082]

Application Example 4

[0083] The only difference from Application Example 1 is that “1mmol CuPt / C sample 1” is replaced with 10mmol CuPt / C sample 1.

[0084] Chromatographic analysis of the reaction solution showed that the conversion rate of 4-aminodiphenylamine was 99.5%, the selectivity of 6PPD was 97.5%, and the ketone-to-alcohol ratio was 95 / 5.

[0085]

Application Example 5

[0086] The only difference from Application Example 1 is that “1mmol CuPt / C sample 1” is replaced with 15mmol CuPt / C sample 1.

[0087] Chromatographic analysis of the reaction solution showed that the conversion rate of 4-aminodiphenylamine was 99.4%, the selectivity of 6PPD was 97.1%, and the ketone-to-alcohol ratio was 93 / 7.

[0088]

Application Example 6

[0089] The only difference from Application Example 4 is that “10 mmol CuPt / C sample 1” is replaced with 10 mmol of the supported metal catalyst CuPt / C sample 2 prepared in Example 2.

[0090] Chromatographic analysis of the reaction solution showed that the conversion rate of 4-aminodiphenylamine was 99.5%, the selectivity of 6PPD was 98.5%, and the ketone-to-alcohol ratio was 95 / 5.

[0091]

Application Example 7

[0092] The only difference from Application Example 4 is that “10 mmol CuPt / C sample 1” is replaced with 10 mmol of the supported metal catalyst CuPt / C sample 3 prepared in Example 3.

[0093] Chromatographic analysis of the reaction solution showed that the conversion rate of 4-aminodiphenylamine was 99.6%, the selectivity of 6PPD was 99.5%, and the ketone-to-alcohol ratio was 99 / 1.

[0094]

Application Example 8

[0095] The only difference from Application Example 4 is that “10 mmol CuPt / C sample 1” is replaced with 10 mmol of the supported metal catalyst CuPt / C sample 4 prepared in Example 4.

[0096] Chromatographic analysis of the reaction solution showed that the conversion rate of 4-aminodiphenylamine was 99.5%, the selectivity of 6PPD was 98.5%, and the ketone-to-alcohol ratio was 96 / 4.

[0097]

Application Example 9

[0098] The only difference from Application Example 4 is that “10 mmol CuPt / C sample 1” is replaced with 10 mmol of the supported metal catalyst CuPt / C sample 5 prepared in Example 5.

[0099] Chromatographic analysis of the reaction solution showed that the conversion rate of 4-aminodiphenylamine was 99.6%, the selectivity of 6PPD was 98.2%, and the ketone-to-alcohol ratio was 92 / 8.

[0100]

Application Example 10

[0101] The only difference from Application Example 7 is that “10 mmol CuPt / C sample 3” is replaced with 10 mmol of the supported metal catalyst CuPt / C sample 6 prepared in Example 6.

[0102] Chromatographic analysis of the reaction solution showed that the conversion rate of 4-aminodiphenylamine was 98.4%, the selectivity of 6PPD was 95.5%, and the ketone-to-alcohol ratio was 92 / 8.

[0103]

Application Example 11

[0104] The only difference from Application Example 7 is that “10 mmol CuPt / C sample 3” is replaced with 10 mmol of the supported metal catalyst CuPt / C sample 7 prepared in Example 7.

[0105] Chromatographic analysis of the reaction solution showed that the conversion rate of 4-aminodiphenylamine was 98.5%, the selectivity of 6PPD was 96.5%, and the ketone-to-alcohol ratio was 93 / 7.

[0106]

Application Example 12

[0107] The only difference from Application Example 7 is that “10 mmol CuPt / C sample 3” is replaced with 10 mmol of the supported metal catalyst CuPt / C sample 8 prepared in Example 8.

[0108] Chromatographic analysis of the reaction solution showed that the conversion rate of 4-aminodiphenylamine was 95.5%, the selectivity of 6PPD was 93.3%, and the ketone-to-alcohol ratio was 91 / 9.

[0109]

Application Example 13

[0110] The only difference from Application Example 7 is that “10 mmol CuPt / C sample 3” is replaced with 10 mmol of the supported metal catalyst CuPt / C sample 9 prepared in Example 9.

[0111] Chromatographic analysis of the reaction solution showed that the conversion rate of 4-aminodiphenylamine was 95.5%, the selectivity of 6PPD was 88%, and the ketone-to-alcohol ratio was 82 / 18.

[0112]

Application Example 14

[0113] The only difference from Application Example 7 is that “10 mmol CuPt / C sample 3” is replaced with 10 mmol of the supported metal catalyst CuPt / C sample 10 prepared in Example 10.

[0114] Chromatographic analysis of the reaction solution showed that the conversion rate of 4-aminodiphenylamine was 91%, the selectivity of 6PPD was 86%, and the ketone-to-alcohol ratio was 90 / 10.

[0115]

Comparative Example 1

[0116] The only difference from Example 3 is that Comparative Example 1 does not include chloroplatinic acid, that is, step (1) is "weigh 2.9g of copper nitrate (10mmol) and 3.0g of mercaptosuccinic acid (MSA, 20mmol), add them to 200mL of deionized water (DI), dissolve and stir thoroughly to obtain solution A1". Finally, Cu / C control sample 1 was obtained.

[0117] [Comparative Example 2]

[0118] The only difference from Example 3 is that Comparative Example 2 does not include copper nitrate. That is, step (1) is "weigh 17.4 g (30 mmol) of chloroplatinic acid and 3.0 g of mercaptosuccinic acid (MSA, 20 mmol), add them to 200 mL of deionized water (DI), dissolve and stir thoroughly to obtain solution A2". Finally, Pt / C control sample 2 was obtained.

[0119] [Comparative Example 3]

[0120] The only difference from Example 3 is that Comparative Example 3 does not include mercaptosuccinic acid, that is, step (1) is "weigh 7.4g (30mmol) of chloroplatinic acid and 2.9g of copper nitrate (10mmol), add them to 200mL of deionized water (DI), dissolve and stir thoroughly to obtain solution A3". Finally, CuPt / C control sample 3 was obtained.

[0121] [Comparative Example 4]

[0122] The only difference from Example 3 is that Comparative Example 4 also added 10 mmol of nickel nitrate, that is, step (1) is "weigh 7.4 g (30 mmol) of chloroplatinic acid, 2.9 g of copper nitrate (10 mmol), and 1.82 g of nickel nitrate (10 mmol) and add them to 200 mL of deionized water (DI), dissolve and stir thoroughly to obtain solution A4". Finally, CuPtNi / C control sample 4 was obtained.

[0123]

Comparative Application Example 1

[0124] The only difference from Application Example 7 is that “10 mmol CuPt / C sample 3” is replaced with 10 mmol Cu / C control sample 1 prepared in Comparative Example 1.

[0125] Chromatographic analysis of the reaction solution showed that the conversion rate of 4-aminodiphenylamine was 92%, the selectivity of 6PPD was 88%, and the ketone-to-alcohol ratio was 70 / 30.

[0126]

Comparative Application Example 2

[0127] The only difference from Application Example 7 is that “10 mmol CuPt / C sample 3” is replaced with 10 mmol Pt / C control sample 2 prepared in Comparative Example 2.

[0128] Chromatographic analysis of the reaction solution showed that the conversion rate of 4-aminodiphenylamine was 99%, the selectivity of 6PPD was 96.5%, and the ketone-to-alcohol ratio was 90 / 10.

[0129]

Comparative Application Example 3

[0130] The only difference from Application Example 7 is that “10 mmol CuPt / C sample 3” is replaced with 10 mmol CuPt / C control sample 3 prepared in Comparative Example 3.

[0131] Chromatographic analysis of the reaction solution showed that the conversion rate of 4-aminodiphenylamine was 65%, the selectivity of 6PPD was 52%, and the ketone-to-alcohol ratio was 80 / 20.

[0132]

Comparative Application Example 4

[0133] The only difference from Application Example 7 is that "10 mmol CuPt / C sample 3" is replaced with 10 mmol CuPtNi / C control sample 4 prepared in Comparative Example 4.

[0134] Chromatographic analysis of the reaction solution showed that the conversion rate of 4-aminodiphenylamine was 98%, the selectivity of 6PPD was 96.5%, and the ketone-to-alcohol ratio was 92 / 8.

[0135] [Test Example]

[0136] Metal elements in the reaction solution were analyzed by ICP. The metal element content of the reaction solution after the reaction in Application Example 7 and Comparative Application Examples 1 and 3 was tested. The test results are shown in Table 1 below:

[0137] Table 1

[0138] <![CDATA[w(Cu) / (g·t -1 )]]> <![CDATA[w(Pt) / (g·t -1 )]]> Application Example 7 0.5 0.22 Comparative Application Example 1 0.7 - Comparative Application Example 3 2.1 1.3

[0139] In summary, as shown in Table 1, the only difference between Application Example 7 and Comparative Application Example 1 is that Comparative Application Example 1's catalyst Cu / C preparation process does not include chloroplatinic acid, containing only copper nitrate and an anchoring agent. In contrast, the copper and platinum lattice insertion in Application Example 7 enhances the catalyst's adsorption and activation capabilities for reactants. Since the catalyst in Comparative Application Example 1 does not contain platinum, less copper detaches from the reaction solution in Application Example 7 after the reaction. The only difference between Application Example 7 and Comparative Application Example 3 is that Comparative Application Example 3's catalyst Cu / C preparation process does not include an anchoring agent, while Application Example 7 contains an anchoring agent. The anchoring agent loads the copper and platinum metal particles onto the support, effectively preventing the detachment and loss of copper and platinum metals.

[0140] Any numerical value mentioned in this invention, if there is only a two-unit interval between any minimum and any maximum value, includes all values ​​that increase by one unit each time from the minimum to the maximum value. For example, if the amount of a component, or the value of a process variable such as temperature, pressure, or time, is stated as 120-150, in this specification it means specifically listing values ​​such as 121-149, 122-148… and 134-136 and 135. For non-integer values, it may be appropriately considered that a unit is 0.1, 0.01, 0.001, or 0.0001. These are merely some specifically specified examples. In this application, in a similar manner, all possible combinations of numerical values ​​between the listed minimum and maximum values ​​are considered to have been disclosed.

[0141] It should be noted that the embodiments described above are only for explaining the present invention and do not constitute any limitation on the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory terms, not limiting terms. Modifications can be made to the present invention within the scope of the claims, and revisions can be made to the present invention without departing from the scope and spirit of the present invention. Although the present invention described herein relates to specific methods, materials, and embodiments, it does not mean that the present invention is limited to the specific examples disclosed herein; on the contrary, the present invention can be extended to all other methods and applications with the same function.

Claims

1. A method for preparing an alloy catalyst, characterized by, include: S1. Disperse the copper source, platinum source and anchoring agent in a solvent by stirring, and then add the reducing agent; S2. Disperse the pretreated carrier into the solution obtained in step S1 for loading; S3. The support loaded in step S2 is dried to obtain the alloy catalyst. The anchoring agent is used to anchor copper and platinum to the carrier.

2. The method of claim 1, wherein the alloy catalyst is prepared by a method comprising: The pretreatment steps of the carrier are as follows: the carrier is first acid-washed, then treated with ammonium carbonate solution, and then washed with deionized water until neutral; preferably, the acid washing, ammonium carbonate solution treatment and deionized water washing are all followed by drying.

3. The method of producing an alloy catalyst according to claim 1 or 2, characterized by, The copper source is at least one of copper chloride, copper nitrate, copper acetate and copper sulfate; And / or, the platinum source is at least one of chloroplatinic acid, chloroplatinate, platinum nitrate and platinum sulfate; And / or, the anchoring agent is at least one of mercaptosuccinic acid, mercaptoethanol, mercaptoacetic acid, thiophenol, cysteine, preferably at least one of mercaptosuccinic acid, mercaptoethanol and mercaptoacetic acid; And / or, the reducing agent is at least one of sodium borohydride, potassium borohydride and ascorbic acid; And / or, the carrier is at least one of activated carbon, carbon nanotubes and graphene, preferably at least one of activated carbon and carbon nanotubes.

4. The method of producing an alloy catalyst according to claim 1 or 2, characterized by, The molar ratio of the copper source, platinum source and anchoring agent is (0.5-2):(0.5-4):(2-10); And / or, the amount of the reducing agent is 2-6 times the total amount of the copper source and the platinum source; And / or, the weight of the carrier is 10-100 times the sum of the weights of the copper source and the platinum source.

5. The method of claim 2, wherein the alloy catalyst is prepared by a method comprising: The acidic solution used for pickling is at least one of sulfuric acid, hydrochloric acid, nitric acid, and phosphoric acid; And / or, the concentration of the ammonium carbonate solution is 10 wt% to 28 wt%.

6. The alloy catalyst prepared by any one of claims 1-5.

7. The alloy catalyst as described in claim 6 is used in the reaction of 4-aminodiphenylamine with methyl isobutyl ketone to prepare antioxidant 6PPD.

8. Use according to claim 7, characterized in that: The molar ratio of 4-aminodiphenylamine to methyl isobutyl ketone is 1:3 to 6; the reaction conditions include: a reaction temperature of 60℃ to 150℃, preferably 70℃ to 100℃; a reaction pressure of 0.6 to 3.0 MPa, preferably 0.8 to 1.5 MPa; and a reaction time of 1 to 2 hours.

9. Use according to claim 7 or 8, characterized in that: The alloy catalyst contains 0.2-20 wt% of 4-aminodiphenylamine, preferably 0.3-10 wt%, and more preferably 1.5-5 wt%.

10. Use according to claim 7 or 8, characterized in that: After the reaction, the conversion rate of 4-aminodiphenylamine was 89.5%–99.8%, the selectivity of 6PPD was 87%–99.5%, and the ketone-to-alcohol ratio was 85 / 15–99 / 1.