CN111718265A - Method for preparing high-purity anti-aging agent IPPD by catalytic hydrogenation of modified supported nickel - Google Patents
Method for preparing high-purity anti-aging agent IPPD by catalytic hydrogenation of modified supported nickel Download PDFInfo
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- CN111718265A CN111718265A CN201910223446.3A CN201910223446A CN111718265A CN 111718265 A CN111718265 A CN 111718265A CN 201910223446 A CN201910223446 A CN 201910223446A CN 111718265 A CN111718265 A CN 111718265A
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- C07C209/00—Preparation of compounds containing amino groups bound to a carbon skeleton
- C07C209/24—Preparation of compounds containing amino groups bound to a carbon skeleton by reductive alkylation of ammonia, amines or compounds having groups reducible to amino groups, with carbonyl compounds
- C07C209/26—Preparation of compounds containing amino groups bound to a carbon skeleton by reductive alkylation of ammonia, amines or compounds having groups reducible to amino groups, with carbonyl compounds by reduction with hydrogen
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Abstract
A method for preparing a high-purity anti-aging agent IPPD through catalytic hydrogenation of modified supported nickel comprises the steps of preparing a raw material solution from raw materials 4-aminodiphenylamine (RT base), acetone and an ionic liquid modifier, filling a supported nickel catalyst into a fixed bed reactor, and inputting the raw material solution into the fixed bed reactor through a continuous feeding and discharging mode to prepare the high-purity anti-aging agent IPPD through catalytic hydrogenation. After hydrogenation reaction, the purity of the product is improved from 82 percent to 99.2 percent, and the ratio of the ketone to the alcohol is also improved to 35/65. The method has the advantages of simplicity, simple operation, high conversion rate and good selectivity, and obviously inhibits the side reactions of benzene ring hydrogenation, polyalkyl reductive alkylation, acetone hydrogenation to isopropanol and the like. The method is beneficial to the industrial production of the copper ion-free high-purity antioxidant IPPD product, the increase of the ketone-alcohol ratio after hydrogenation reaction, the reduction of the consumption of acetone and hydrogen and the remarkable reduction of the production cost.
Description
Technical Field
The invention belongs to the technical field of organic synthesis, and particularly relates to a method for preparing a high-purity antioxidant IPPD through catalytic hydrogenation of modified supported nickel.
Background
The rubber antioxidant IPPD is a universal excellent antioxidant, has excellent protection performance on ozone and flex cracking, and is suitable for natural rubber, butadiene styrene rubber, butadiene rubber, chloroprene rubber, nitrile rubber and latex. The anti-aging agent IPPD is the most outstanding and perfect representative so far, has comprehensive protection efficiency, high ozone resistance and flexibility resistance, has inhibition effect on heat, oxygen and harmful metals (such as copper, manganese and the like), and is widely applied to tire treads and tire sidewalls, rubber tubes, cables, seals and the like. The excellent protective performance of the anti-aging agent IPPD is second to that of the anti-aging agent 6PPD due to the toxicity, volatility, washing loss rate and solvent resistance of the anti-aging agent IPPD, which are more irritant to the skin than the anti-aging agent 6 PPD. In recent years, aiming at the defects of the anti-aging agent IPPD, an optimized anti-aging agent IPPD has been developed. The product is characterized in that on the basis of keeping the excellent anti-aging performance of the original IPPD, the molecular structure of the product is adjusted by a special complexing process by using organic polymeric salt as a complexing modifier, and the number of active groups is increased, so that the product is optimized and improved in the aspects of water extraction rate, color migration, dispersibility, synergistic effect and the like, and the performance of the product is comprehensively improved. The performance of the product can be completely compared with that of an anti-aging agent 6PPD, and the market share of the product tends to be gradually enlarged.
At present, the commercial production method of the anti-aging agent IPPD comprises the following steps: schiff base hydrogenation, phenol amine condensation, hydroxylamine reductive alkylation, quinone imine condensation, reductive amination, and the like. The Schiff base hydrogenation method and the phenol amine condensation method have long process flow and complex process, and the condensation reaction needs to add a solid catalyst, so that the separation and purification cost is increased, and economic loss is avoided. The hydroxylamine reduction alkylation method and the quinoneimine condensation method have certain advancement, but the preparation process of raw materials is complex, the pollution is serious, and the raw materials are not easy to obtain. At present, the industrial production process of the anti-aging agent IPPD at home and abroad mainly adopts a method of reducing and alkylating 4-aminodiphenylamine (RT base) and acetone as raw materials by one-step condensation. The main reaction is as follows:
side reactions
The most important side reactions are hydrogenation of benzene ring, reduction of alkylation by polyalkyl and reduction of acetone to isopropanol.
Reductive alkylation generally employs a catalytic hydrogenation process. The catalyst may be classified into a noble metal catalyst, a copper-based catalyst and a nickel-based catalyst. The catalyst may be classified into a noble metal catalyst, a copper-based catalyst and a nickel-based catalyst. Noble metal catalysts such as: pt, Ru, Pd, etc. have high activity, good selectivity, good heat resistance, and strong poison resistance, but they are expensive, so noble metal catalysts are often used for the tank reaction. Although the copper catalyst has low price and is suitable for continuous and large-scale fixed bed production process, the preparation of the anti-aging agent IPPD by adopting the catalytic hydrogenation of the copper catalyst also has a plurality of defects. For example, the main reaction selectivity is low, the product purity is low, and the purity of the domestic antioxidant IPPD product is 92-95%. The catalytic hydrogenation also can obviously amplify side reaction, and acetone is completely converted into isopropanol at the same time after the hydrogenation reaction. This not only increases the consumption of acetone as a raw material, but also reduces its concentration and thereby affects the speed of the main reaction. The recovered isopropanol needs to be catalytically dehydrogenated again at high temperature to acetone, which greatly increases the production cost. In addition, copper ions in the copper-based catalyst can be lost into the product, which can cause adverse effects on downstream products. The nickel-based catalyst has the advantages that nickel is cheap, the price of platinum is 2000 times that of nickel, and the nickel-based catalyst is more economical in industrial production. When the nickel catalyst is used for catalytic hydrogenation to prepare the anti-aging agent IPPD, the main reaction selectivity is between 60 and 82 percent, and the product purity is low. The main reasons are as follows: reducing and alkylating N polyalkyl; ② the benzene ring in the Schiff base and the surface of the catalyst crystal particle generate a coplanar surface, thereby generating a plurality of hydrogenation reactions of two benzene rings.
US3366684, US4043942, etc. do a lot of work in improving the selectivity of the main reaction and inhibiting the side reaction of ketone hydrogenation, but use noble metal catalysts, which have too high investment cost and are not suitable for domestic fixed bed production process.
The catalyst CN 101204658A is a copper-zinc-aluminum catalyst which is high in reaction activity, not easy to pulverize, but low in selectivity, long in induction period and low in main content of an anti-aging agent IPPD.
CN 102319568A provides an improved condensation reduction alkylation catalyst. The catalyst is a copper catalyst and is mainly characterized in that the catalyst component contains silicon element, and the molar ratio of copper to silicon is (0.5-10): 1. the catalyst has high selectivity in the production process of the anti-aging agent IPPD, and the main content of the anti-aging agent IPPD is increased to 97.3 percent at most. The side reaction of ketone hydrogenation to generate alcohol is also obviously inhibited. However, the induction period of the catalyst is still longer, and the residual amount of RT base is still 1.5 percent after 312 hours.
In view of the above problems, there is a need for technical improvements by taking advantageous measures.
Disclosure of Invention
The invention aims to provide a nickel-loaded high-efficiency catalytic system taking ionic liquid as a modifier for preparing a high-purity anti-aging agent IPPD. The invention also aims to replace a copper catalyst with a supported nickel catalyst, eliminate the adverse effect of copper ions on products, improve the selectivity of reductive alkylation reaction by modified catalysis, and reduce side reactions, thereby improving the ketone-alcohol ratio of the antioxidant IPPD after hydrogenation reaction.
The main technical scheme of the invention is as follows: the method for preparing the high-purity antioxidant IPPD by catalytic hydrogenation of modified supported nickel is characterized in that raw materials of 4-aminodiphenylamine, acetone and an ionic liquid modifier are prepared into a raw material solution, a supported nickel catalyst is filled in a fixed bed reactor, the raw material solution is conveyed into the fixed bed reactor in a continuous feeding and discharging mode to prepare the antioxidant IPPD by catalytic hydrogenation, and the reaction is carried out according to the following steps:
a, after a reaction system is replaced by nitrogen, replacing by hydrogen, continuously inputting a modified solvent in a continuous feeding and discharging mode, mixing the modified solvent with the hydrogen, heating by a preheater, and then entering a fixed bed reactor filled with a supported nickel catalyst for water activation, wherein the modified solvent consists of isopropanol and ionic liquid;
b, preparing raw materials 4-aminodiphenylamine, acetone and an ionic liquid modifier into a raw material solution, continuously inputting the raw material solution to perform catalytic hydrogenation reaction after activation of the loaded nickel is finished, and overflowing a reducing solution from the top of the reactor;
and C, transferring the reaction liquid into a distillation kettle for distillation, respectively extracting water, acetone and isopropanol, washing away the ionic liquid modifier by using a small amount of hot water when the temperature is raised to be more than 100 ℃, and then carrying out reduced pressure distillation to obtain the product anti-aging agent IPPD.
In general, the reaction system in step A is replaced with nitrogen 3 times, and then replaced with hydrogen 3 times.
The ionic liquid modifier is one or more of 1-butyl-3-methyl-imidazole boron tetrafluoride ([ Bmim ] BF4), 1-benzyl-3-methyl-imidazole boron tetrafluoride ([ Bzmim ] BF4), 1- (2-hydroxyethyl) -3-methyl-imidazole boron tetrafluoride ([ C20Hmim ] BF4) and 1- (2-hydroxyethyl) -3-ethyl-benzimidazole boron tetrafluoride ([ C20HeBim ] BF 4).
The pressure of the reactor in the step A is 1.5-4.0 MPa, and the temperature of the preheater and the temperature of the reactor are the same and are 95-250 ℃; the activation time is 5 to 12 hours.
The mass ratio of the isopropanol to the ionic liquid is 1000: (0.1-10).
And the flow rate of the modifying solvent input in the step A is 10-100 mL/h.
The raw material solution in the step B is composed of raw materials of 4-aminodiphenylamine, acetone and an ionic liquid modifier, wherein the molar ratio of the 4-aminodiphenylamine to the acetone is 1: (2-10), wherein the volume ratio of acetone to the ionic liquid modifier is 1000: (0.1-10), the catalytic hydrogenation reaction time is 1-10 hours, and the reduction time is 2-10 hours.
And C, the vacuum degree of the reduced pressure distillation in the step C is 3-100 kPa.
And C, controlling the temperature of the reduced pressure distillation kettle in the step C to be 150-220 ℃.
The supported nickel catalyst consists of nickel and gamma-Al 2O3, wherein the supported amount of the nickel is 5-55%.
The invention has the following advantages:
1. the supported nickel catalyst is adopted to replace a copper catalyst, a small amount of ionic liquid modification reagent is added into the raw material solution to modify the supported nickel catalyst, the conversion rate and the selectivity can be obviously improved, the RT conversion rate is more than or equal to 99.8%, and the selectivity of the anti-aging agent IPPD is more than or equal to 99.2%. The ratio of the ketol after hydrogenation reaction is also increased to 35/65;
2. the problem that the use performance of downstream products is influenced due to the loss of copper ions of the copper catalyst is avoided;
3. the production cost is reduced: because the side reaction is less, the consumption of acetone and hydrogen is reduced, the energy consumption of the high-temperature catalytic dehydrogenation of the isopropanol is also reduced, the running cost of the device is greatly saved, and the production cost is effectively reduced;
4. the product quality is good: the modified supported nickel is used for catalyzing, so that the side reaction of ketone-to-alcohol is reduced, the side reaction of benzene ring hydrogenation and polyalkylation is also inhibited, and the product purity is improved to 99.2% from 82%;
5. the modified catalyst improves the conversion rate and yield, and has no influence on the service life of the catalyst. The invention only carries out proper fine adjustment on the original fixed bed production process, and is convenient for realizing industrialization.
Detailed Description
The treatment method of the present invention will be described in detail with reference to examples and comparative examples.
Example 1
Adding RT base, acetone and [ Bmim ] into the blending tank]BF4And uniformly stirring to prepare a raw material solution, wherein the molar ratio of RT base to acetone is 1: 5.5, acetone and [ Bmim ]]BF4The volume ratio is 1000: 2.5.
loading granular NH-202 type supported nickel catalyst in a fixed bed, replacing the reaction system with nitrogen for 3 times, replacing the reaction system with hydrogen for 3 times, introducing hydrogen, adjusting the pressure in the fixed bed to 4MPa, and introducing isopropanol and [ 2 ] at a speed of 50mL/hBmim]BF4Composition modifying solvent (isopropanol and [ Bmim ]]BF4The volume ratio is 1000: 2.5), mixing the modified solvent with hydrogen, passing through a preheater, and then entering the fixed bed reactor until the modified solvent is filled in the fixed bed reactor. Slowly raising the temperature of the preheater and the fixed bed, and when the temperature reaches 180 ℃, maintaining for several hours, and carrying out activation treatment. At the temperature, the system pressure is adjusted to 2.0MPa, the materials are replaced by raw material solution, and the feeding speed is adjusted to 20 mL/h. After the catalytic hydrogenation reaction, the reducing liquid overflows from the top of the fixed bed reactor. Transferring the reducing solution into a distillation still for distillation, respectively extracting water, acetone and isopropanol, and washing with a small amount of hot water when the temperature is raised to above 100 ℃ [ Bmim ]]BF4And then carrying out reduced pressure distillation to obtain the product anti-aging agent IPPD. The relative contents of ketone and alcohol in the reducing solution and the purity of the anti-aging agent IPPD in the product are respectively measured by adopting gas chromatography according to the specified method of GB/T8828-2003. The measurement results are shown in the first comparison table.
Comparative example 1
A comparative experiment was carried out under the same conditions without modification of the supported nickel catalyst of the NH-202 type. The specific operating conditions were the same as in example 1, except that [ Bmim ] was not added to the raw material solution]BF4. The test results are shown in the comparison table I
TABLE-comparison table of IPPD test for preparing antioxidant by NH-202 type supported nickel modified catalytic hydrogenation
Example 2
The specific operation conditions are the same as example 1, except that the ionic liquid is prepared from [ Bmim ]]BF4By changing to [ Bmim ]]BF4And [ Bzmim]BF4The mixed liquid (volume ratio is 1: 1) is used for changing the supported nickel catalyst from NH-202 type to NH-301 type. The test results are shown in the second comparative table.
Comparative example 2
A comparative test was carried out under the same conditions without modifying the NH-301 type supported nickel catalyst. The operation conditions were the same as in example 2 except that the mixed ionic liquid of example 2 was not added to the raw material solution. The test results are shown in the second comparative table.
Comparison table for IPPD test of preparing antioxidant by modified catalytic hydrogenation of epi-di NH-301 type supported nickel
Example 3
The specific operation conditions were the same as in example 1 except that the supported nickel catalyst was changed from NH-202 type to NH-301 type. The test results are shown in the third comparison table.
Example 4
The specific operation conditions are the same as example 1, except that the ionic liquid is prepared from [ Bmim ]]BF4By changing to [ Bmim ]]BF4And [ Bzmim]BF4The mixture (volume ratio 1: 1). The test results are shown in comparative table four.
Example 5
The specific operation conditions are the same as example 1, except that the ionic liquid is prepared from [ Bmim ]]BF4By substitution of [ Bzmim]BF4. The test results are shown in the fifth comparative table.
Example 6
The specific operation conditions are the same as example 1, except that the ionic liquid is prepared from [ Bmim ]]BF4By substitution of [ Bzmim]BF4The supported nickel catalyst is changed from NH-202 type to NH-301 type. The test results are shown in comparative table six.
Example 7
The operation conditions were the same as in example 1 except that the system pressure was adjusted to 2.5MPa and the feed rate was adjusted to 25 mL/h. The test results are shown in the seventh comparative table.
The invention uses a small amount of ionic liquid to modify the supported nickel catalyst, adopts a fixed bed production process, and prepares the high-purity antioxidant IPPD by carrying out the catalytic hydrogenation reaction of the modified supported nickel in a continuous feeding and discharging mode. Combining the experimental data of the above examples and comparative examples, the present invention has the following advantages: the quality of the product after hydrogenation reaction can be obviously improved, and the purity of the product is improved from 82 percent to 99.2 percent; secondly, the problem that the use performance of IPPD products is influenced by the loss of copper ions of the copper catalyst is solved. Side reactions are reduced, and the ratio of ketol to ketol is also increased to 35/65; ③ the conversion rate of RT base is up to 99.98 percent, and fourthly, the product yield is up to more than 99 percent. In addition, the process not only reduces the consumption of acetone and hydrogen, but also reduces the energy consumption of the high-temperature catalytic dehydrogenation of the isopropanol, greatly saves the operating cost of the device, effectively reduces the production cost, is simple and convenient to operate, and is easy to realize industrialization.
Claims (10)
1. A method for preparing a high-purity anti-aging agent IPPD by catalytic hydrogenation of modified supported nickel is characterized in that raw materials of 4-aminodiphenylamine, acetone and an ionic liquid modifier are prepared into a raw material solution, a supported nickel catalyst is filled in a fixed bed reactor, the raw material solution is conveyed into the fixed bed reactor in a continuous feeding and discharging mode to prepare the anti-aging agent IPPD by catalytic hydrogenation, and the reaction is carried out according to the following steps:
a, after a reaction system is replaced by nitrogen, replacing by hydrogen, continuously inputting a modified solvent in a continuous feeding and discharging mode, mixing the modified solvent with the hydrogen, heating by a preheater, and then entering a fixed bed reactor filled with a supported nickel catalyst for water activation, wherein the modified solvent consists of isopropanol and ionic liquid;
b, preparing raw materials 4-aminodiphenylamine, acetone and an ionic liquid modifier into a raw material solution, continuously inputting the raw material solution to perform catalytic hydrogenation reaction after activation of the loaded nickel is finished, and overflowing a reducing solution from the top of the reactor;
and C, transferring the reaction liquid into a distillation kettle for distillation, respectively extracting water, acetone and isopropanol, washing away the ionic liquid modifier by using a small amount of hot water when the temperature is raised to be more than 100 ℃, and then carrying out reduced pressure distillation to obtain the product anti-aging agent IPPD.
2. The method according to claim 1, wherein the reaction system is replaced with nitrogen 3 times and then replaced with hydrogen 3 times in the step A.
3. The method of claim 1, wherein the ionic liquid modifier is one or more of 1-butyl-3-methyl-imidazole boron tetrafluoride, 1-benzyl-3-methyl-imidazole boron tetrafluoride, 1- (2-hydroxyethyl) -3-methyl-imidazole boron tetrafluoride, and 1- (2-hydroxyethyl) -3-ethyl-benzimidazole boron tetrafluoride.
4. The method according to claim 1, wherein the reactor pressure in step A is 1.5-4.0 MPa, and the temperature of the preheater and the reactor is 95-250 ℃; the activation time is 5 to 12 hours.
5. The process according to claim 1, characterized in that the mass ratio of isopropanol to ionic liquid is 1000: (0.1-10).
6. The method according to claim 1, wherein the flow rate of the modifying solvent fed in step A is 10 to 100 mL/h.
7. The method according to claim 1, wherein the raw material solution in step B is composed of raw material 4-aminodiphenylamine, acetone and an ionic liquid modifier, and the molar ratio of 4-aminodiphenylamine to acetone is 1: (2-10), wherein the volume ratio of acetone to the ionic liquid modifier is 1000: (0.1-10), the catalytic hydrogenation reaction time is 1-10 hours, and the reduction time is 2-10 hours.
8. The method according to claim 1, wherein the degree of vacuum in the vacuum distillation in step C is 3 to 100 kPa.
9. The method according to claim 1, wherein the temperature of the vacuum still in step C is 150 to 220 ℃.
10. The method of claim 1, wherein the supported nickel catalyst is comprised of nickel and γ -Al2O3The nickel-based alloy material comprises the following components, wherein the loading amount of nickel is 5-55%.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104418757A (en) * | 2013-08-20 | 2015-03-18 | 中国石油化工股份有限公司 | Method for preparing anti-aging agent 4010NA through modification-catalytic hydrogenation |
| CN105566125A (en) * | 2014-10-17 | 2016-05-11 | 中国石油化工股份有限公司 | Method for compounding rubber antioxidant 6PPD and IPPD through nickel catalyst |
| US20170275233A1 (en) * | 2015-12-22 | 2017-09-28 | Eastman Chemical Company | Methods of making compounds and mixtures having antidegradant and antifatigue efficacy |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104418757A (en) * | 2013-08-20 | 2015-03-18 | 中国石油化工股份有限公司 | Method for preparing anti-aging agent 4010NA through modification-catalytic hydrogenation |
| CN105566125A (en) * | 2014-10-17 | 2016-05-11 | 中国石油化工股份有限公司 | Method for compounding rubber antioxidant 6PPD and IPPD through nickel catalyst |
| US20170275233A1 (en) * | 2015-12-22 | 2017-09-28 | Eastman Chemical Company | Methods of making compounds and mixtures having antidegradant and antifatigue efficacy |
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