Preparation method of catalyst for preparing 2-ethylhexanol through liquid-phase hydrogenation of 2-ethylhexenal

Abstract

The invention relates to the technical field of catalyst preparation, in particular to a preparation method of a catalyst for preparing 2-ethylhexanol through liquid-phase hydrogenation of 2-ethylhexenal. The method comprises the following steps: 1, preparing a urea solution with a certain concentration; 2, weighing Ni (NO3) 2.6 H2O and Cu (NO3) 2.3 H2O according to a certain proportion, and dissolving the Ni (NO3) 2.6 H2O and the Cu (NO3) 2.3 H2O in a urea solution to form a mixed solution; 3, weighing silica sol, adding the silica sol into the mixed solution, and continuously stirring; 4, slowly heating the mixed solution to 90-100 DEG C while stirring, and evaporating to dryness to obtain a solid; and 5, drying and roasting the solid to obtain the catalyst precursor. The prepared catalyst can catalyze 2-ethyl hexenal hydrogenation to prepare 2-ethyl hexanol in a high-activity and high-selectivity manner under a mild condition.

Description

Technical field:

[0001] The invention relates to the technical field of catalyst preparation, and in particular to a method for preparing a catalyst for preparing 2-ethylhexanol by liquid-phase hydrogenation of 2-ethylhexenal. Background technology:

[0002] Chinese patents CN105080549A and CN105080549B disclose a catalyst for preparing 2-ethylhexanol by gas phase hydrogenation of octenal and its preparation method. A highly selective octenal hydrogenation catalyst prepared by distributed precipitation is proposed, which solves the problem of easy pulverization of the catalyst during use. The catalyst is mainly composed of 25% to 35% copper oxide, 45% to 60% zinc oxide, 2% to 10% aluminum oxide, 2% to 10% silicon dioxide, and 0.01% to 1% additive. The specific surface area of ​​the catalyst is 30m 2 / g~60m 2 / g, pore volume is 0.17mL / g~0.30mL / g, and average pore radius is 5nm~10nm. The catalyst prepared by the inventive method has high activity and 2-ethylhexanol selectivity, and has better use strength and lower color number, and is suitable for the reaction process of octenal gas phase hydrogenation to 2-ethylhexanol.

[0003] Chinese patent CN114082421A discloses a hydrogenation catalyst and a preparation method thereof and an application thereof in the hydrogenation of isooctylaldehyde. The hydrogenation catalyst comprises a carrier and an active component loaded on the carrier, wherein the carrier is alumina and / or phosphorus-modified alumina, and the active component is nickel; the specific surface area of ​​the hydrogenation catalyst is 200 to 630 m2 / g, the pore volume is 2 to 4 cm3 / g, and the most probable pore diameter is 10 to 30 nm. The hydrogenation catalyst is applied to the hydrogenation of isooctylaldehyde to isooctylaldehyde and isooctyl alcohol reaction, which can improve the catalytic activity and selectivity.

[0004] Chinese patent CN105854919A discloses a low-temperature hydrogenation catalyst for α,β# unsaturated aldehydes and its preparation method and application. The catalyst described in the present invention is a hexagonal boron nitride-supported precious metal catalyst, which is prepared by impregnating an active precious metal salt on a pretreated carrier and reducing it. Through the fine control and effective combination of carrier pretreatment, impregnation and reduction treatment, the active component can be effectively dispersed on the carrier, and good performance is shown when the content of the precious metal active component is low.

[0005] Chinese patent CN1478596A discloses a process for preparing isooctyl alcohol by hydrogenating a mixture of isooctyl aldehyde and a catalyst used therein, and particularly relates to a process for preparing isooctyl alcohol by liquid phase hydrogenation of a mixture of isooctyl aldehyde and octenol using a novel catalyst and a catalyst used therein. The catalyst uses metal nickel as an active component, alkaline earth metal oxides and / or aluminum oxide as a promoter, and a silicon-containing compound as a carrier. The raw material of the carrier is a porous silicon-containing compound and / or a silicon-containing compound that is viscous in an aqueous solution; the active component nickel is loaded on the carrier in the form of coprecipitation, kneading, or coprecipitation-kneading with the carrier, and is prepared by roasting at 300-800°C. Summary of the invention:

[0006] The technical problem to be solved by the present invention is to provide a method for preparing a catalyst for preparing 2-ethylhexanol by liquid-phase hydrogenation of 2-ethylhexenal, wherein the prepared catalyst can catalyze the hydrogenation of 2-ethylhexenal to prepare 2-ethylhexanol with high activity and high selectivity under mild conditions, thereby overcoming the problems of low activity and selectivity of the existing liquid-phase hydrogenation catalyst for octenal and high impurity content of the octanol product after hydrogenation.

[0007] The technical solution adopted by the present invention is: a preparation method of a catalyst for preparing 2-ethylhexanol by liquid phase hydrogenation of 2-ethylhexenal, the method comprising the following steps:

[0008] Step 1: prepare a urea solution of a certain concentration;

[0009] Step 2: Weigh Ni(NO 3 ) 2 6H 2 O, Cu(NO 3 ) 2 ·3H 2 O, and dissolved in urea solution to form a mixed solution;

[0010] Step 3: Weigh silica sol and add it to the mixed solution and stir continuously;

[0011] Step 4: slowly heating the mixed solution to 90°C to 100°C while stirring, and evaporating the water to obtain a solid;

[0012] Step 5: The solid material is dried and calcined to obtain a catalyst precursor.

[0013] Furthermore, the concentration of the urea solution in step 1 is 0.05 mol / L to 0.5 mol / L.

[0014] Furthermore, the Ni(NO 3 ) 2 6H 2 O, Cu(NO 3 )2 ·3H 2 O、SiO 2 The molar ratio of substances is x:y:6, where x+y+6=10.

[0015] Furthermore, the concentration of the silica sol in step three is 20% to 50%.

[0016] Furthermore, in step 5, the solid drying temperature is 100°C to 180°C.

[0017] Furthermore, in the step 5, the solid matter is calcined at a temperature of 400°C to 650°C.

[0018] Furthermore, the reduction activation conditions of the prepared catalyst precursor are: reduction at a constant temperature of 300° C. for 12 hours in a mixed gas with a hydrogen-nitrogen flow rate of 1:50 to 1:0.

[0019] The beneficial effect of the present invention is that the catalyst prepared by the present invention is used for the reaction of preparing octanol by liquid phase hydrogenation of octenal after reduction activation, and has the characteristics of high catalytic hydrogenation activity and high selectivity of product octanol. Description of the drawings:

[0020] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] Figure 1 is the H of the catalyst in Example 1 2 -TPR diagram. Specific implementation method:

[0022] Comparative Example 1

[0023] Will Ni(NO 3 ) 2 6H 2 O and Cu(NO 3 )2·3H 2 O was prepared into solution a in a molar ratio of 3:1, and equal volumes were immersed in SiO 2 The catalyst precursor X was obtained by drying the catalyst in an oven at 120°C after standing for 24 h (Ni, Cu, Si molar ratio was 3:1:6) in a muffle furnace at 500°C.

[0024] Example 1

[0025] Prepare 0.1 mol / L urea solution; Ni(NO 3 ) 2 6H 2 O and Cu(NO 3 )2·3H 2O was added to the urea solution in a molar ratio of 3:1 to form a mixed solution; 25% silica sol (Ni, Cu, Si molar ratio of 3:1:6) was added to the mixed solution; under stirring, it was slowly heated to 90°C, the water was evaporated, dried in an oven at 120°C, and then calcined at 500°C in a muffle furnace to obtain a catalyst precursor A.

[0026] Example 2

[0027] Prepare 0.05 mol / L urea solution; Ni(NO 3 ) 2 6H 2 O and Cu(NO 3 )2·3H 2 O was added to the urea solution in a molar ratio of 3:1 to form a mixed solution; 25% silica sol (Ni, Cu, Si molar ratio of 3:1:6) was added to the mixed solution; under stirring, it was slowly heated to 90°C, the water was evaporated, dried in an oven at 120°C, and then calcined at 500°C in a muffle furnace to obtain a catalyst precursor B.

[0028] Example 3

[0029] Prepare 0.5 mol / L urea solution; Ni(NO 3 ) 2 6H 2 O and Cu(NO 3 )2·3H 2 O was added to the urea solution in a molar ratio of 3:1 to form a mixed solution; 25% silica sol (Ni, Cu, Si molar ratio of 3:1:6) was added to the mixed solution; under stirring, it was slowly heated to 90°C, the water was evaporated, dried in an oven at 120°C, and then calcined at 500°C in a muffle furnace to obtain a catalyst precursor C.

[0030] Example 4

[0031] Prepare 0.1 mol / L urea solution; Ni(NO 3 ) 2 6H 2 O and Cu(NO 3 )2·3H 2 O was added to the urea solution in a molar ratio of 4:0 to form a mixed solution; 25% silica sol (Ni, Cu, Si molar ratio of 4:0:6) was added to the mixed solution; under stirring, it was slowly heated to 90°C, the water was evaporated, dried in an oven at 120°C, and then calcined at 500°C in a muffle furnace to obtain a catalyst precursor D.

[0032] Example 5

[0033] Prepare 0.1 mol / L urea solution; Ni(NO3 ) 2 6H 2 O and Cu(NO 3 )2·3H 2 O was added to the urea solution in a molar ratio of 2:2 to form a mixed solution; 25% silica sol (Ni, Cu, Si molar ratio of 2:2:6) was added to the mixed solution; under stirring, it was slowly heated to 90°C, the water was evaporated, dried in an oven at 120°C, and then calcined at 500°C in a muffle furnace to obtain a catalyst precursor E.

[0034] Example 6

[0035] Prepare 0.1 mol / L urea solution; Ni(NO 3 ) 2 6H 2 O and Cu(NO 3 )2·3H 2 O was added to the urea solution in a molar ratio of 1:3 to form a mixed solution; 25% silica sol (Ni, Cu, Si molar ratio of 1:3:6) was added to the mixed solution; under stirring, it was slowly heated to 90°C, the water was evaporated, dried in an oven at 120°C, and then calcined at 500°C in a muffle furnace to obtain a catalyst precursor F.

[0036] Example 7

[0037] Prepare 0.1 mol / L urea solution; Ni(NO 3 ) 2 6H 2 O and Cu(NO 3 )2·3H 2 O was added to the urea solution in a molar ratio of 0:4 to form a mixed solution; 25% silica sol (Ni, Cu, Si molar ratio of 0:4:6) was added to the mixed solution; under stirring, it was slowly heated to 90°C, the water was evaporated, dried in an oven at 120°C, and then calcined at 500°C in a muffle furnace to obtain a catalyst precursor G.

[0038] Example 8

[0039] Prepare 0.1 mol / L urea solution; Ni(NO 3 ) 2 6H 2 O and Cu(NO 3 )2·3H 2 O was added to the urea solution in a molar ratio of 3:1 to form a mixed solution; 10% silica sol (Ni, Cu, Si molar ratio of 3:1:6) was added to the mixed solution; under stirring, it was slowly heated to 90°C, the water was evaporated, and it was dried in an oven at 120°C, and then calcined at 500°C in a muffle furnace to obtain a catalyst precursor H.

[0040] Example 9

[0041] Prepare 0.1 mol / L urea solution; Ni(NO 3 ) 2 6H 2 O and Cu(NO 3 )2·3H 2 O was added to the urea solution in a molar ratio of 3:1 to form a mixed solution; 40% silica sol (Ni, Cu, Si molar ratio of 3:1:6) was added to the mixed solution; under stirring, it was slowly heated to 90°C, the water was evaporated, and it was dried in an oven at 120°C, and then calcined at 500°C in a muffle furnace to obtain a catalyst precursor I.

[0042] Example 10

[0043] Prepare 0.1 mol / L urea solution; Ni(NO 3 ) 2 6H 2 O and Cu(NO 3 )2·3H 2 O was added to the urea solution in a molar ratio of 3:1 to form a mixed solution; 50% silica sol (Ni, Cu, Si molar ratio of 3:1:6) was added to the mixed solution; under stirring, it was slowly heated to 90°C, the water was evaporated, dried in an oven at 120°C, and then calcined at 500°C in a muffle furnace to obtain a catalyst precursor J.

[0044] Embodiment 11

[0045] Prepare 0.1 mol / L urea solution; Ni(NO 3 ) 2 6H 2 O and Cu(NO 3 )2·3H 2 O is added to the urea solution in a molar ratio of 3:1 to form a mixed solution; 25% silica sol (Ni, Cu, Si molar ratio is 3:1:6) is added to the mixed solution K; under stirring, it is slowly heated to 100°C, the water is evaporated, and it is dried in an oven at 120°C, and then calcined at 500°C in a muffle furnace to obtain a catalyst precursor K.

[0046] Example 12

[0047] Prepare 0.1 mol / L urea solution; Ni(NO 3 ) 2 6H 2 O and Cu(NO 3 )2·3H 2O was added to the urea solution in a molar ratio of 3:1 to form a mixed solution; 25% silica sol (Ni, Cu, Si molar ratio of 3:1:6) was added to the mixed solution; under stirring, it was slowly heated to 90°C, the water was evaporated, dried in an oven at 100°C, and then calcined in a muffle furnace at 400°C to obtain a catalyst precursor L.

[0048] Embodiment 13

[0049] Prepare 0.1 mol / L urea solution; Ni(NO 3 ) 2 6H 2 O and Cu(NO 3 )2·3H 2 O is added to the urea solution in a molar ratio of 3:1 to form a mixed solution; 25% silica sol (Ni, Cu, Si molar ratio is 3:1:6) is added to the mixed solution; under stirring, it is slowly heated to 90°C, the water is evaporated, and it is dried in an oven at 180°C, and then calcined at 650°C in a muffle furnace to obtain a catalyst precursor M.

[0050] The catalyst precursors prepared in Comparative Example 1 and Examples 1-13 were activated by reduction and then used for the liquid phase hydrogenation of octenal to produce octanol at mild conditions of 120° C. to 130° C. The reaction performance is shown in Table 1.

[0051] Table 1 Octenal liquid phase hydrogenation performance of catalysts

[0052] catalyst Octenal conversion rate (%) Octanol selectivity (%) A 99.9 99.8 B 99.6 99.5 C 95.9 98.8 D 84.7 98.9 E 95.1 99.0 F 93.3 98.2 G 82.2 97.6 H 99.8 99.8 I 99.1 99.1 J 98.4 98.7 K 91.4 97.6 L 99.3 99.3 M 98.9 99.1 X 81.3 95.4

[0053] As shown in Table 1, the catalysts prepared in Examples 1-13 can catalyze the hydrogenation of 2-ethylhexenal to 2-ethylhexanol at a mild condition of 120° C. to 130° C. with high activity and high selectivity.

[0054] It can be understood that the above specific description of the present invention is only used to illustrate the present invention and is not limited to the technical solutions described in the embodiments of the present invention. Those skilled in the art should understand that the present invention can still be modified or replaced by equivalents to achieve the same technical effects; as long as the use requirements are met, they are within the protection scope of the present invention.

Claims

1. A method for preparing a catalyst for preparing 2-ethylhexanol by liquid phase hydrogenation of 2-ethylhexenal, characterized in that: The steps of this method are as follows: Step 1: prepare a urea solution of a certain concentration; Step 2: Weigh Ni(NO3)2·6H2O and Cu(NO3)2·3H2O in a certain ratio and dissolve them in urea solution to form a mixed solution; Step 3: Weigh silica sol and add it to the mixed solution and stir continuously; Step 4: slowly heating the mixed solution to 90°C to 100°C while stirring, and evaporating the water to obtain a solid; Step 5: The solid material is dried and calcined to obtain a catalyst precursor.

2. The method for preparing a catalyst for preparing 2-ethylhexanol by liquid phase hydrogenation of 2-ethylhexenal according to claim 1, wherein: The concentration of the urea solution in step 1 is 0.05 mol / L to 0.5 mol / L.

3. The method for preparing a catalyst for preparing 2-ethylhexanol by liquid phase hydrogenation of 2-ethylhexenal according to claim 1, wherein: The molar ratio of Ni(NO3)2·6H2O, Cu(NO3)2·3H2O and SiO2 in the mixed solution of step three is x:y:6, wherein x+y+6=10.

4. The method for preparing a catalyst for preparing 2-ethylhexanol by liquid phase hydrogenation of 2-ethylhexenal according to claim 1, characterized in that: The concentration of the silica sol in step three is 20% to 50%.

5. The method for preparing the catalyst for preparing 2-ethylhexanol by liquid phase hydrogenation of 2-ethylhexenal according to claim 1, characterized in that: In the step 5, the solid drying temperature is 100°C to 180°C.

6. The method for preparing the catalyst for preparing 2-ethylhexanol by liquid phase hydrogenation of 2-ethylhexenal according to claim 1, characterized in that: In the step 5, the solid material is calcined at a temperature of 400°C to 650°C.

7. The method for preparing the catalyst for preparing 2-ethylhexanol by liquid phase hydrogenation of 2-ethylhexenal according to claim 1, characterized in that: The reduction activation conditions of the prepared catalyst precursor are: reduction at a constant temperature of 300° C. for 12 hours in a mixed gas with a hydrogen-nitrogen flow rate of 1:50 to 1:0.

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