Preparation method and application of catalytic hydrogenation reduction catalyst

Abstract

The invention relates to a preparation method of a catalytic hydrogenation reduction catalyst. The method comprises the following steps: dissolving Ni (NO3) 2.6 H2O and Co (NO3) 2.6 H2O in deionized water to prepare a solution I; dissolving K2CO3 in deionized water to prepare a solution II; slowly dropwise adding the solution I and the solution II into deionized water while violently stirring at room temperature, and controlling the pH value to be 7-8; after dripping, aging for 1-2 hours, filtering, washing and drying to obtain a filter cake; and fully mixing the filter cake with gamma-Al2O3 and a small amount of deionized water, grinding, drying, and roasting at high temperature to obtain the Ni-Co-gamma-Al2O3 catalyst. Meanwhile, the invention also discloses application of the catalyst. The method is simple in process and low in cost, and the product purity and yield are improved; the obtained catalyst can be applied to the production of benzotriazole ultraviolet light absorbers, and the application verification is carried out in UV-326, UV-327, UV-328, UV-329, UV-P and UV-234.

Description

Technical Field

[0001] The invention relates to the field of ultraviolet absorbers, and in particular to a preparation method of a catalytic hydrogenation reduction catalyst and application thereof. Background Art

[0002] Benzotriazole compounds have unique physical and chemical properties due to the heterocyclic ring with three nitrogen atoms in the molecule, so they have a broad structural basis in ultraviolet absorbers. Benzotriazole ultraviolet absorbers are widely used in polymer materials due to their good physical and chemical properties. Its color is relatively light and does not affect the appearance of the material; good toxicity data is healthy and environmentally friendly, in line with the concept of green chemistry; good oil resistance to prevent self-decomposition; low volatility to prevent self-degradation; washing resistance, good stability; good compatibility with polymers, easy to add; good light stability, strong light absorption ability.

[0003] The preparation method of benzotriazole ultraviolet absorbers is mainly to obtain an azo intermediate through diazotization and coupling reaction, and finally obtain the final target product through reduction reaction. The catalytic hydrogenation reduction method has become the mainstream method for preparing benzotriazole ultraviolet absorbers due to its low price and green environmental protection. Hydrogen is used as a reducing agent and the azo intermediate HAB is converted into benzotriazole under the action of a suitable catalyst. At present, the catalytic hydrogenation reduction catalysts reported include Raney nickel (CN102399198, CN103351349), Pt-C (CN106008380, CN109529820), Pd-C (CN110396070), Pt@Mg-MOF-74 (CN116589 421), Pd / Pt-MgO (CN112645892), nickel nitrate hexahydrate and 1H-benzotriazole reaction, calcined catalyst (CN115920898), and Ni-diatomaceous earth (CN103508967).

[0004] However, existing benzotriazole ultraviolet absorbers have problems such as complex preparation process, high cost, and low catalyst reusability, which slows down the industrialization process. Therefore, preparing a highly selective, recyclable catalytic hydrogenation reduction catalyst with a simple preparation process and low cost is an urgent problem to be solved in the industrialization of catalytic hydrogenation reduction preparation of benzotriazole ultraviolet absorbers. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a method for preparing a catalytic hydrogenation reduction catalyst with simple process and low cost.

[0006] Another technical problem to be solved by the present invention is to provide application of the catalytic hydrogenation reduction catalyst.

[0007] In order to solve the above problems, the present invention provides a method for preparing a catalytic hydrogenation reduction catalyst, characterized in that: the method is to prepare Ni(NO 3 ) 2 6H 2 O、Co(NO 3 ) 2 6H 2 O was dissolved in deionized water to prepare a solution I with a mass concentration of 7.94-12.70%; K 2 CO 3 Dissolve in deionized water to prepare a solution II with a mass concentration of 6.41-9.39%; slowly drop solution I and solution II into deionized water at room temperature while vigorously stirring, and control the pH value to be maintained between 7 and 8; after the dropwise addition, age for 1-2 hours, filter, wash with deionized water, and dry to obtain a filter cake; the filter cake and γ-Al 2 O 3 , a small amount of deionized water, and then ground, dried, and calcined at high temperature in a muffle furnace to obtain Ni-Co-γ-Al 2 O 3 catalyst.

[0008] The Ni(NO 3 ) 2 6H 2 O and γ-Al 2 O 3 The mass ratio of Co(NO 3 ) 2 6H 2 O and γ-Al 2 O 3 The mass ratio of K is 0.25~1.23:1; 2 CO 3 With the γ-Al 2 O 3 The mass ratio is 0.24~1.76:1.

[0009] The conditions for high temperature calcination in the muffle furnace are a temperature of 400-600° C. and a time of 3-6 hours.

[0010] A Ni-Co-γ-Al prepared by the above method 2 O 3 catalyst.

[0011] A Ni-Co-γ-Al 2 O 3 The catalyst is characterized in that: the Ni-Co-γ-Al 2 O 3Before using the catalyst, it is reduced at high temperature for 2 to 5 hours in a hydrogen atmosphere at a pressure of 0.5 to 3 MPa and a temperature of 300 to 400°C.

[0012] A Ni-Co-γ-Al 2 O 3 The application of the catalyst is characterized in that: the Ni-Co-γ-Al 2 O 3 Catalyst used in the synthesis of benzotriazole ultraviolet absorbers.

[0013] The benzotriazole ultraviolet light absorber is synthesized by the following method: (1) At -5~5℃, add substituted o-nitroaniline in batches to a 30% sulfuric acid solution by volume, stir evenly, and continue to drop a 30% sodium nitrite aqueous solution by mass concentration. After the dropwise addition, react for 0.75~2h. After the reaction is completed, add aminosulfonic acid at -5~5℃ to decompose nitrous acid, filter and wash with water to obtain a diazonium salt filtrate; (2) adding sodium dodecyl sulfate to a substituted phenol aqueous solution having a mass concentration of 11.49-28.39% in batches to prepare a uniform emulsion having a concentration of 13.53-23.55%, and then dropping the diazonium salt filtrate into the solution to carry out a coupling reaction after cooling to room temperature, and simultaneously dropping a NaOH solution, while always keeping the reaction system neutral to weakly alkaline during the dropping, and continuing the reaction until the end after the dropping is completed; filtering, washing with water, washing with anhydrous ethanol, and drying to obtain an azo intermediate; (3) The azo intermediate is under a pressure of 1 to 5 MPa, Ni-Co-γ-Al 2 O 3 The product is reduced to a benzotriazole ultraviolet absorber compound under the catalysis of a catalyst; after the reaction is completed, the precipitated product is dissolved in dichloromethane, and the catalyst is filtered and recovered; the organic phase is concentrated, dissolved with a solvent, decolorized, cooled and crystallized to obtain the final product.

[0014] The substituted o-nitroaniline in step (1) includes o-nitroaniline or p-chloro-o-nitroaniline.

[0015] In the step (1), the mass ratio of substituted o-nitroaniline, sulfuric acid solution, sodium nitrite aqueous solution and aminosulfonic acid is 1:5.94~7.41:1.27~1.60:0.12~0.14.

[0016] The substituted phenol in the substituted phenol aqueous solution in step (2) includes one of 2-tert-butyl-4-methylphenol, 2,4-di-tert-butylphenol, 2,4-di-tert-amylphenol, p-tert-octylphenol, p-methylphenol, and 2,4-di(α,α-dimethylbenzyl)phenol.

[0017] Compared with the prior art, the present invention has the following advantages: 1. The present invention has developed a new catalytic hydrogenation reduction method for γ-Al 2 O 3 Compared with the existing technology, the loaded nickel-cobalt bifunctional catalyst is greener and more efficient. It not only avoids the environmental pollution caused by the use of chemical reduction methods, but also improves the product purity and yield, while reducing production costs and simplifying process operations.

[0018] 2. The catalytic hydrogenation reduction catalyst obtained by the present invention can be used in the production of benzotriazole ultraviolet absorbers, and its application has been verified in UV-326, UV-327, UV-328, UV-329, UV-P and UV-234. DETAILED DESCRIPTION

[0019] A method for preparing a catalytic hydrogenation reduction catalyst, the method comprising: 3 ) 2 6H 2 O、Co(NO 3 ) 2 6H 2 O was dissolved in deionized water to prepare a solution I with a mass concentration of 7.94-12.70%; K 2 CO 3 Dissolve in deionized water to prepare solution II with a mass concentration of 6.41-9.39%; slowly drop solution I and solution II into deionized water at room temperature while vigorously stirring, and control the pH value to be between 7 and 8; after dropping, age for 1-2 hours, filter, wash with deionized water, and dry to obtain a filter cake; the filter cake and γ-Al 2 O 3 , a small amount of deionized water, and then ground, dried, and calcined at high temperature in a muffle furnace to obtain Ni-Co-γ-Al 2 O 3 catalyst.

[0020] Among them: Ni(NO 3 ) 2 6H 2 O and γ-Al 2 O 3 The mass ratio of Co(NO 3 ) 2 6H 2 O and γ-Al 2 O 3 The mass ratio of K is 0.25~1.23:1; 2 CO 3 With γ-Al 2 O 3 The mass ratio is 0.24~1.76:1.

[0021] The conditions for high temperature roasting in a muffle furnace are a temperature of 400~600°C and a time of 3~6 hours.

[0022] The Ni-Co-γ-Al 2 O 3 Before using the catalyst, it is reduced at high temperature for 2 to 5 hours in a hydrogen atmosphere at a pressure of 0.5 to 3 MPa and a temperature of 300 to 400°C.

[0023] A Ni-Co-γ-Al 2 O 3 Catalyst application: Ni-Co-γ-Al 2 O 3 The catalyst is used in the synthesis of benzotriazole ultraviolet absorbers. The specific synthesis method is as follows: ⑴ -5~5℃, add substituted o-nitroaniline in batches to a 30% sulfuric acid solution by volume, stir evenly, continue to add a 30% sodium nitrite aqueous solution by mass concentration, and react for 0.75~2h after the addition is completed; after the reaction is completed, add aminosulfonic acid at -5~5℃ to decompose nitrous acid, filter and wash with water to obtain the diazonium salt filtrate.

[0024] Wherein: the substituted o-nitroaniline includes o-nitroaniline or p-chloro-o-nitroaniline. The mass ratio of the substituted o-nitroaniline, the sulfuric acid solution, the sodium nitrite aqueous solution, and the aminosulfonic acid is 1:5.94~7.41:1.27~1.60:0.12~0.14.

[0025] ⑵ Sodium dodecyl sulfate is added to a substituted phenol aqueous solution with a mass concentration of 11.49-28.39% in batches to prepare a uniform emulsion with a concentration of 13.53-23.55%. After cooling to room temperature, the diazonium salt filtrate is added dropwise to carry out coupling reaction, and NaOH solution is added dropwise at the same time. When adding dropwise, the reaction system is always kept neutral to weakly alkaline. After the addition is completed, the reaction is continued until the end; after filtering, washing with water, washing with anhydrous ethanol, and drying, the azo intermediate is obtained. The product does not need to be purified.

[0026] The substituted phenol in the substituted phenol aqueous solution includes one of 2-tert-butyl-4-methylphenol, 2,4-di-tert-butylphenol, 2,4-di-tert-amylphenol, p-tert-octylphenol, p-methylphenol and 2,4-di(α,α-dimethylbenzyl)phenol.

[0027] ⑶ Azo intermediates under 1~5MPa pressure, Ni-Co-γ-Al 2 O 3The product is reduced to a benzotriazole ultraviolet absorber compound under the catalysis of a catalyst; after the reaction is completed, the precipitated product is dissolved in dichloromethane, and the catalyst is recovered by filtration; the organic phase is concentrated, dissolved with a solvent, decolorized, cooled and crystallized to obtain the final product, a benzotriazole ultraviolet absorber.

[0028] The mass ratios in the present invention are all g / g, and the volume ratios are all mL / mL.

[0029] Example 1: Preparation of Catalyst 1 25.27 g Ni(NO 3 ) 2 6H 2 O, 25.19 g Co(NO 3 ) 2 6H 2 O was dissolved in 350 mL of deionized water to prepare solution I. 23.97 g of K 2 CO 3 Dissolve in 350 mL of deionized water to prepare solution II. Stir vigorously at room temperature, and slowly drop solution I and solution II into 250 mL of deionized water. During the dropwise addition, strictly control the pH value to be between 7 and 8. After the dropwise addition, age for 2 hours, filter, wash the filter cake with deionized water, and dry at 110°C for 8 hours. The obtained solid is mixed with 102 g of γ-Al 2 O 3 , 100 mL of deionized water, and then ground. The resulting mixture was dried at 110 °C for 8 h, and then calcined in a muffle furnace at 400 °C for 6 h to obtain catalyst 1. Before use, the catalyst must be reduced at 300 °C for 2 h in a 3 MPa hydrogen atmosphere.

[0030] Example 2: Preparation of Catalyst 2 50.75 g Ni(NO 3 ) 2 6H 2 O, 50.37 g Co(NO 3 ) 2 6H 2 O was dissolved in 500 mL of deionized water to prepare solution I. 48.04 g of K 2 CO 3 Dissolve in 500 mL of deionized water to prepare solution II. Stir vigorously at room temperature and slowly drop solution I and solution II into 400 mL of deionized water. During the dropwise addition, strictly control the pH value to be between 7 and 8. After the dropwise addition, age for 1 hour, filter, wash the filter cake with deionized water, and dry at 110°C for 8 hours. The obtained solid is mixed with 102 g of γ-Al 2 O 3, 100 mL of deionized water, and then ground. The resulting mixture was dried at 110 °C for 8 h, and then calcined in a muffle furnace at 500 °C for 5 h to obtain catalyst 2. Before use, the catalyst must be reduced at 350 °C for 3 h in a 2 MPa hydrogen atmosphere.

[0031] Example 3: Preparation of Catalyst 3 Put 75.82g Ni(NO 3 ) 2 6H 2 O, 75.56g Co(NO 3 ) 2 6H 2 O was dissolved in 700 mL of deionized water to prepare solution I. 71.92 g of K 2 CO 3 Dissolve in 700 mL of deionized water to prepare solution II. Stir vigorously at room temperature and slowly drop solution I and solution II into 500 mL of deionized water. During the dropwise addition, strictly control the pH value to be between 7 and 8. After the dropwise addition, age for 1.5 hours, filter, wash the filter cake with deionized water, and dry at 110°C for 8 hours. The obtained solid is mixed with 102 g of γ-Al 2 O 3 , 100 mL of deionized water, and then ground. The resulting mixture was dried at 110 °C for 8 h, and then calcined at 600 °C in a muffle furnace for 4 h to obtain catalyst 3. Before use, the catalyst must be reduced at 400 °C for 2 h in a 1 MPa hydrogen atmosphere.

[0032] Example 4: Preparation of Catalyst 4 Put 101.09g Ni(NO 3 ) 2 6H 2 O, 75.56g Co(NO 3 ) 2 6H 2 O was dissolved in 700 mL of deionized water to prepare solution I. 72.50 g of K 2 CO 3 Dissolve in 700 mL of deionized water to prepare solution II. Stir vigorously at room temperature and slowly drop solution I and solution II into 500 mL of deionized water. During the dropwise addition, strictly control the pH value to be between 7 and 8. After the dropwise addition, age for 1.5 hours, filter, wash the filter cake with deionized water, and dry at 110°C for 8 hours. The obtained solid is mixed with 102 g of γ-Al 2 O 3, 100 mL of deionized water, and then ground. The resulting mixture was dried at 110 °C for 8 h, and then calcined at 500 °C in a muffle furnace for 3 h to obtain catalyst 4. Before use, the catalyst must be reduced at 350 °C for 3 h in a 0.5 MPa hydrogen atmosphere.

[0033] Example 5: Preparation of Catalyst 5 126.36 g Ni(NO 3 ) 2 6H 2 O, 50.37 g Co(NO 3 ) 2 6H 2 O was dissolved in 700 mL of deionized water to prepare solution I. 72.02 g of K 2 CO 3 Dissolve in 700 mL of deionized water to prepare solution II. Stir vigorously at room temperature and slowly drop solution I and solution II into 500 mL of deionized water. During the dropwise addition, strictly control the pH value to be between 7 and 8. After the dropwise addition, age for 1.5 hours, filter, wash the filter cake with deionized water, and dry at 110°C for 8 hours. The obtained solid is mixed with 102 g of γ-Al 2 O 3 , 100 mL of deionized water, and then ground. The resulting mixture was dried at 110 °C for 8 h, and then calcined at 500 °C in a muffle furnace for 3 h to obtain catalyst 5. Before use, the catalyst must be reduced at 350 °C for 3 h in a 1 MPa hydrogen atmosphere.

[0034] Example 6: Preparation of Catalyst 6 50.75 g Ni(NO 3 ) 2 6H 2 O, 100.74 g Co(NO 3 ) 2 6H 2 O was dissolved in 700 mL of deionized water to prepare solution I. 71.95 g of K 2 CO 3 Dissolve in 700 mL of deionized water to prepare solution II. Stir vigorously at room temperature and slowly drop solution I and solution II into 500 mL of deionized water. During the dropwise addition, strictly control the pH value to be between 7 and 8. After the dropwise addition, age for 1.5 hours, filter, wash the filter cake with deionized water, and dry at 110°C for 8 hours. The obtained solid is mixed with 102 g of γ-Al 2 O 3, 100 mL of deionized water, and then ground. The resulting mixture was dried at 110 °C for 8 h, and then calcined at 500 °C in a muffle furnace for 3 h to obtain catalyst 6. Before use, the catalyst must be reduced at 350 °C for 3 h in a 1 MPa hydrogen atmosphere.

[0035] Example 7: Preparation of Catalyst 7 25.27 g Ni(NO 3 ) 2 6H 2 O, 125.93 g Co(NO 3 ) 2 6H 2 O was dissolved in 700 mL of deionized water to prepare solution I. 71.80 g of K 2 CO 3 Dissolve in 700 mL of deionized water to prepare solution II. Stir vigorously at room temperature and slowly drop solution I and solution II into 500 mL of deionized water. During the dropwise addition, strictly control the pH value to be between 7 and 8. After the dropwise addition, age for 1.5 hours, filter, wash the filter cake with deionized water, and dry at 110°C for 8 hours. The obtained solid is mixed with 102 g of γ-Al 2 O 3 , 100 mL of deionized water, and then ground. The resulting mixture was dried at 110 °C for 8 h, and then calcined at 500 °C in a muffle furnace for 3 h to obtain catalyst 7. Before use, the catalyst must be reduced at 350 °C for 3 h in a 1 MPa hydrogen atmosphere.

[0036] Example 8: Application of Catalyst 1 in UV-326 Synthesis ⑴ Add 48mL of 30% sulfuric acid solution to a 500mL round-bottom flask, add 10.35g of p-chloro-o-nitroaniline to the sulfuric acid solution in batches at 0℃ while stirring, stir evenly, then slowly add 10.8mL of 30% sodium nitrite to the flask, and continue to react at 0℃ for 1h. The reaction is terminated when the starch potassium iodide test paper shows a negative result. Add 1.2g of aminosulfonic acid to decompose nitrous acid at this reaction temperature, stir for 30min, filter, wash the solid three times with water, and the obtained diazonium salt filtrate does not need to be purified and is directly used in the next step.

[0037] ⑵ Add 11.8g 2-tert-butyl-4-methylphenol and 60mL water to a 500mL three-necked bottle, stir at 50°C until completely dissolved, then add 1.6g sodium dodecyl sulfate in batches to make a uniform emulsion, cool to room temperature, and add the diazonium salt filtrate obtained above to the emulsion at a uniform rate for coupling reaction under stirring, and at the same time, add 120mL 2M NaOH solution, and keep the reaction system neutral to weakly alkaline during the addition process. After the addition is completed, continue the reaction at room temperature for 2h to produce a large number of solid particles and terminate the reaction. Filter, wash with water, wash with ethanol, and dry to obtain an azo intermediate with a yield of 89%. The product does not need to be purified and is directly used in the next reaction.

[0038] ⑶ Add 17.39g of azo intermediate, 0.87g of KOH, 1.74g of catalyst 1 and 200mL of methanol to a 500mL autoclave, replace with hydrogen three times, inflate to 1MPa, react in an oil bath at 65°C for 4h, add dichloromethane to the reaction system after the reaction is completed to dissolve the precipitated product, and filter and recover the catalyst. Remove the solvent from the organic phase, add 300mL of methanol, heat and reflux until the solid is completely dissolved, add activated carbon for decolorization, filter hot, and cool the filtrate to room temperature for crystallization to obtain 13.58g of product UV-326 with a yield of 86%.

[0039] Example 9: Application of Catalyst 2 in the Synthesis of UV-327 ⑴ Add 48mL of 30% sulfuric acid solution to a 500mL round-bottom flask, add 10.35g of p-chloro-o-nitroaniline to the sulfuric acid solution in batches at 0℃ while stirring, stir evenly, then slowly add 10.8mL of 30% sodium nitrite to the flask, and continue to react at 0℃ for 1h. The reaction is terminated when the starch potassium iodide test paper shows a negative result. Add 1.2g of aminosulfonic acid to decompose nitrous acid at this reaction temperature, stir for 30min, filter, wash the solid three times with water, and the obtained diazonium salt filtrate does not need to be purified and is directly used in the next step.

[0040] ⑵ Add 14.86g 2,4-di-tert-butylphenol and 60mL water to a 500mL three-necked bottle, stir at 50°C until completely dissolved, then add 1.6g sodium dodecyl sulfate in batches to make a uniform emulsion, cool to room temperature, and add the diazonium salt filtrate obtained above to the emulsion at a uniform rate for coupling reaction under stirring, and at the same time, add 120mL 2M NaOH solution, and keep the reaction system neutral to weakly alkaline during the addition process. After the addition is completed, continue the reaction at room temperature for 2h to produce a large number of solid particles and terminate the reaction. Filter, wash with water, wash with ethanol, and dry to obtain an azo intermediate with a yield of 91%. The product does not need to be purified and is directly used in the next step.

[0041] ⑶ Add 19.49g of azo intermediate, 0.97g of KOH, 2.92g of catalyst 2 and 200mL of methanol to a 500mL autoclave, replace with hydrogen three times, inflate to 5MPa, react in an oil bath at 65°C for 4h, add dichloromethane to the reaction system after the reaction is completed to dissolve the precipitated product, and filter and recover the catalyst. Remove the solvent from the organic phase, add 300mL of methanol, heat and reflux until the solid is completely dissolved, add activated carbon for decolorization, filter hot, and cool the filtrate to room temperature for crystallization to obtain 16.28g of product UV-327 with a yield of 91%.

[0042] Example 10: Application of Catalyst 3 in UV-328 Synthesis (1) Add 48 mL of 30% sulfuric acid solution to a 500 mL round-bottom flask. Add 8.29 g of o-nitroaniline to the sulfuric acid solution in batches at 0°C while stirring. After stirring evenly, slowly add 10.8 mL of 30% sodium nitrite to the flask and continue the reaction at 0°C for 1 hour. The reaction is terminated when the starch potassium iodide test paper shows a negative result. Add 1.2 g of aminosulfonic acid at this reaction temperature to decompose nitrous acid. Stir for 30 minutes and filter. Wash the solid three times with water. The diazonium salt filtrate obtained does not need to be purified and is directly used in the next step.

[0043] (2) Add 16.88g 2,4-di-tert-amylphenol and 60mL water to a 500mL three-necked flask, stir at 50°C until completely dissolved, then add 1.6g sodium dodecyl sulfate in batches to make a uniform emulsion, cool to room temperature, and add the diazonium salt filtrate obtained above to the emulsion at a uniform rate for coupling reaction under stirring, and at the same time add 120mL 2 M NaOH solution, and keep the reaction system neutral to weakly alkaline during the addition process. After the addition is completed, continue the reaction at room temperature for 2h to produce a large amount of solid particles, and end the reaction. Filter, wash with water, wash with ethanol, and dry to obtain the azo intermediate with a yield of 90%. The product does not need to be purified and is directly used in the next reaction.

[0044] (3) 19.17 g of azo intermediate, 0.96 g of KOH, 3.83 g of catalyst 3 and 200 mL of methanol were added to a 500 mL autoclave, replaced with hydrogen three times, inflated to 1 MPa, and reacted in an oil bath at 65°C for 4 h. After the reaction was completed, dichloromethane was added to the reaction system to dissolve the precipitated product, and the catalyst was filtered and recovered. The organic phase was desolventized, 300 mL of methanol was added, and the mixture was heated to reflux until the solid was completely dissolved. Activated carbon was added for decolorization, and the mixture was filtered hot. The filtrate was cooled to room temperature for crystallization to obtain 16.34 g of product UV-328 with a yield of 93%.

[0045] Example 11: Application of Catalyst 4 in the Synthesis of UV-329 (1) Add 48 mL of 30% sulfuric acid solution to a 500 mL round-bottom flask. Add 8.29 g of o-nitroaniline to the sulfuric acid solution in batches at 0°C while stirring. After stirring evenly, slowly add 10.8 mL of 30% sodium nitrite to the flask and continue the reaction at 0°C for 1 hour. The reaction is terminated when the starch potassium iodide test paper shows a negative result. Add 1.2 g of aminosulfonic acid at this reaction temperature to decompose nitrous acid. Stir for 30 minutes and filter. Wash the solid three times with water. The diazonium salt filtrate obtained does not need to be purified and is directly used in the next step.

[0046] (2) Add 11.80 g of 4-tert-octylphenol and 60 mL of water to a 500 mL three-necked bottle, stir at 50°C until completely dissolved, then add 1.6 g of sodium dodecyl sulfate in batches to make a uniform emulsion, cool to room temperature, and add the diazonium salt filtrate obtained above to the emulsion at a uniform rate under stirring for coupling reaction. At the same time, add 120 mL of 2 M NaOH solution, and keep the reaction system neutral to weakly alkaline during the addition process. After the addition is completed, continue the reaction at room temperature for 2 hours to produce a large number of solid particles, and terminate the reaction. Filter, wash with water, wash with ethanol, and dry to obtain the azo intermediate with a yield of 92%. The product does not need to be purified and is directly used in the next reaction.

[0047] (3) 17.77 g of azo intermediate, 0.89 g of KOH, 3.55 g of catalyst 4 and 200 mL of methanol were added to a 500 mL autoclave, replaced with hydrogen three times, aerated to 2 MPa, and reacted in an oil bath at 65°C for 4 h. After the reaction was completed, dichloromethane was added to the reaction system to dissolve the precipitated product, and the catalyst was filtered and recovered. The organic phase was desolventized, 300 mL of methanol was added, and the mixture was heated to reflux until the solid was completely dissolved. Activated carbon was added for decolorization, and the mixture was filtered hot. The filtrate was cooled to room temperature for crystallization to obtain 14.55 g of product UV-329 with a yield of 90%.

[0048] Example 12: Application of Catalyst 5 in UV-P Synthesis (1) Add 48 mL of 30% sulfuric acid solution to a 500 mL round-bottom flask. Add 8.29 g of o-nitroaniline to the sulfuric acid solution in batches at 0°C while stirring. After stirring evenly, slowly add 10.8 mL of 30% sodium nitrite to the flask and continue the reaction at 0°C for 1 hour. The reaction is terminated when the starch potassium iodide test paper shows a negative result. Add 1.2 g of aminosulfonic acid at this reaction temperature to decompose nitrous acid. Stir for 30 minutes and filter. Wash the solid three times with water. The diazonium salt filtrate obtained does not need to be purified and is directly used in the next step.

[0049] (2) Add 7.79 g of p-methylphenol and 60 mL of water to a 500 mL three-necked bottle, stir at 50°C until completely dissolved, then add 1.6 g of sodium dodecyl sulfate in batches to make a uniform emulsion, cool to room temperature, and add the diazonium salt filtrate obtained above to the emulsion at a uniform rate under stirring for coupling reaction. At the same time, add 120 mL of 2 M NaOH solution, and keep the reaction system neutral to weakly alkaline during the addition process. After the addition is completed, continue the reaction at room temperature for 2 hours to produce a large number of solid particles, and terminate the reaction. Filter, wash with water, wash with ethanol, and dry to obtain the azo intermediate with a yield of 90%. The product does not need to be purified and is directly used in the next reaction.

[0050] (3) 12.86 g of azo intermediate, 6.43 g of KOH, 2.57 g of catalyst 5 and 200 mL of methanol were added to a 500 mL autoclave, replaced with hydrogen three times, inflated to 3 MPa, and reacted in an oil bath at 65°C for 4 h. After the reaction was completed, dichloromethane was added to the reaction system to dissolve the precipitated product, and the catalyst was filtered and recovered. The organic phase was desolventized, 300 mL of methanol was added, and the mixture was heated to reflux until the solid was completely dissolved. Activated carbon was added for decolorization, and the mixture was filtered hot. The filtrate was cooled to room temperature for crystallization to obtain 9.80 g of product UV-P with a yield of 87%.

[0051] Example 13: Application of Catalyst 6 in UV-234 Synthesis (1) Add 48 mL of 30% sulfuric acid solution to a 500 mL round-bottom flask. Add 8.29 g of o-nitroaniline to the sulfuric acid solution in batches at 0°C while stirring. After stirring evenly, slowly add 10.8 mL of 30% sodium nitrite to the flask and continue the reaction at 0°C for 1 hour. The reaction is terminated when the starch potassium iodide test paper shows a negative result. Add 1.2 g of aminosulfonic acid at this reaction temperature to decompose nitrous acid. Stir for 30 minutes and filter. Wash the solid three times with water. The diazonium salt filtrate obtained does not need to be purified and is directly used in the next step.

[0052] (2) Add 23.79g 2,4-bis(α,α-dimethylbenzyl)phenol and 60mL water to a 500mL three-necked flask, stir at 50°C until completely dissolved, then add 1.6g sodium dodecyl sulfate in batches to make a uniform emulsion, cool to room temperature, and add the diazonium salt filtrate obtained above to the emulsion at a uniform rate for coupling reaction under stirring, and at the same time add 120mL 2 MNaOH solution, and keep the reaction system neutral to weakly alkaline during the addition process. After the addition is completed, continue the reaction at room temperature for 2h to produce a large amount of solid particles, and end the reaction. Filter, wash with water, wash with ethanol, and dry to obtain the azo intermediate with a yield of 88%. The product does not need to be purified and is directly used in the next reaction.

[0053] (3) Add 23.98g of azo intermediate, 11.99g of KOH, 4.80g of catalyst 6 and 200mL of methanol to a 500mL autoclave, replace with hydrogen three times, fill to 4MPa, react in an oil bath at 65°C for 4h, add dichloromethane to the reaction system after the reaction is completed to dissolve the precipitated product, and filter to recover the catalyst. Remove the solvent from the organic phase, add 300mL of methanol, heat and reflux until the solid is completely dissolved, add activated carbon for decolorization, filter hot, and cool the filtrate to room temperature for crystallization to obtain 18.65g of product UV-234 with a yield of 84%.

Claims

1. A method for preparing a catalytic hydrogenation reduction catalyst, characterized in that: The method comprises the following steps: dissolving Ni(NO3)2·6H2O and Co(NO3)2·6H2O in deionized water to prepare a solution I with a mass concentration of 7.94-12.70%; dissolving K2CO3 in deionized water to prepare a solution II with a mass concentration of 6.41-9.39%; slowly dropping solution I and solution II into deionized water under vigorous stirring at room temperature, and controlling the pH value to be maintained between 7 and 8; aging for 1-2 hours after dropping, filtering, washing with deionized water, and drying to obtain a filter cake; fully mixing the filter cake with γ-Al2O3 and a small amount of deionized water, grinding, drying, and then high-temperature roasting in a muffle furnace to obtain a Ni-Co-γ-Al2O3 catalyst.

2. The method for preparing a catalytic hydrogenation reduction catalyst according to claim 1, characterized in that: The mass ratio of the Ni(NO3)2·6H2O to the γ-Al2O3 is 0.25~1.24:1; the mass ratio of the Co(NO3)2·6H2O to the γ-Al2O3 is 0.25~1.23:1; the mass ratio of the K2CO3 to the γ-Al2O3 is 0.24~1.76:

1.

3. The method for preparing a catalytic hydrogenation reduction catalyst according to claim 1, characterized in that: The conditions for high temperature calcination in the muffle furnace are a temperature of 400-600° C. and a time of 3-6 hours.

4. A Ni-Co-γ-Al2O3 catalyst prepared by the method according to any one of claims 1 to 3.

5. A Ni-Co-γ-Al2O3 catalyst as claimed in claim 4, characterized in that: Before use, the Ni-Co-γ-Al2O3 catalyst is reduced at high temperature for 2-5 hours in a hydrogen atmosphere at a pressure of 0.5-3 MPa and a temperature of 300-400°C.

6. The use of a Ni-Co-γ-Al2O3 catalyst as claimed in claim 4, characterized in that: The Ni-Co-γ-Al2O3 catalyst is used for the synthesis of benzotriazole ultraviolet absorbers.

7. The use of a Ni-Co-γ-Al2O3 catalyst as claimed in claim 6, characterized in that: The benzotriazole ultraviolet light absorber is synthesized by the following method: (1) At -5~5℃, add substituted o-nitroaniline in batches to a 30% sulfuric acid solution by volume, stir evenly, and continue to drop a 30% sodium nitrite aqueous solution by mass concentration. After the dropwise addition, react for 0.75~2h. After the reaction is completed, add aminosulfonic acid at -5~5℃ to decompose nitrous acid, filter and wash with water to obtain a diazonium salt filtrate; (2) adding sodium dodecyl sulfate to a substituted phenol aqueous solution having a mass concentration of 11.49-28.39% in batches to prepare a uniform emulsion having a concentration of 13.53-23.55%, cooling to room temperature and then dropping the diazonium salt filtrate therein to carry out a coupling reaction, while simultaneously dropping a NaOH solution, while always keeping the reaction system neutral to weakly alkaline during the dropping, and continuing the reaction after the dropping is completed; After filtering, washing with water, washing with anhydrous ethanol, and drying, the azo intermediate is obtained; ⑶ The azo intermediate is reduced to a benzotriazole ultraviolet absorber compound under a pressure of 1 to 5 MPa and a Ni-Co-γ-Al2O3 catalyst; after the reaction is completed, the precipitated product is dissolved in dichloromethane, and the catalyst is filtered and recovered; the organic phase is concentrated, solvent dissolved, decolorized, cooled and crystallized to obtain the final product.

8. The use of a Ni-Co-γ-Al2O3 catalyst as claimed in claim 7, characterized in that: The substituted o-nitroaniline in step (1) includes o-nitroaniline or p-chloro-o-nitroaniline.

9. The use of a Ni-Co-γ-Al2O3 catalyst as claimed in claim 7, characterized in that: In the step (1), the mass ratio of substituted o-nitroaniline, sulfuric acid solution, sodium nitrite aqueous solution and aminosulfonic acid is 1:5.94~7.41:1.27~1.60:0.12~0.

14.

10. The use of a Ni-Co-γ-Al2O3 catalyst as claimed in claim 7, characterized in that: The substituted phenol in the substituted phenol aqueous solution in step (2) includes one of 2-tert-butyl-4-methylphenol, 2,4-di-tert-butylphenol, 2,4-di-tert-amylphenol, p-tert-octylphenol, p-methylphenol, and 2,4-di(α,α-dimethylbenzyl)phenol.