Octene aldehyde liquid phase hydrogenation catalyst and preparation method thereof

Abstract

The application provides a preparation method of an octene aldehyde liquid-phase hydrogenation catalyst, and steps of the method comprise the following: (1) preparing a salt solution containing nickel ions, copper ions and aluminum ions, heating to 40-80 DEG C, adding a basic precipitator to react, and aging after the reaction is completed; (2) uniformly mixing the precipitate obtained after aging in step (1) with silica sol to obtain slurry; (3) washing and filtering the slurry, then adding alkali metal carbonate powder and boron nitride solid, uniformly mixing, and then shaping, drying and calcining to obtain the octene aldehyde liquid-phase hydrogenation catalyst. The preparation method is simple, green, environmentally friendly and easy to industrialize, the conversion rate and selectivity of the obtained octene aldehyde liquid-phase hydrogenation catalyst are high, and the catalyst is stable in performance and durable.

Description

Technical Field

[0001] This invention relates to the technical field of liquid-phase hydrogenation of octenal, and specifically to a liquid-phase hydrogenation catalyst for octenal and its preparation method. Background Technology

[0002] Butanol and octanol are generally referred to as butanol and octanol because they can be produced in the same unit using a hydroxyl synthesis method. Both are colorless, transparent, flammable, oily liquids with a characteristic odor and can form azeotropes with water and many compounds. Butanol and octanol are important raw materials for the synthesis of fine chemical products, mainly used in the production of plasticizers, solvents, dehydrating agents, defoamers, dispersants, flotation agents, petroleum additives, and synthetic fragrances. Current butanol and octanol production methods all require the hydrogenation of butenal / butyraldehyde and octenal to produce butanol and octanol. The aldehyde hydrogenation section is a crucial component of the butanol and octanol production process, and it is divided into liquid-phase hydrogenation and gas-phase hydrogenation processes. Regardless of the hydrogenation process, the most critical factor for improving the product quality and economic efficiency of butanol and octanol production is the selection of a suitable catalyst. A suitable catalyst can improve the activity and selectivity of hydrogenation and reduce by-products.

[0003] Existing technologies have disclosed various hydrogenation catalysts. For example, EP0394842A1 discloses a catalyst for hydrogenating aliphatic unsaturated compounds, containing 20-75% by weight nickel oxide, 10-75% by weight zirconium dioxide, and 5-50% by weight copper oxide. This catalyst has an optimal operating temperature of not less than 180°C and a maximum pressure reaching ~35 MPa. Achieving 100% conversion requires high temperature and pressure, limiting its widespread application. To improve this application, patent CN1097484C discloses an aldehyde liquid-phase hydrogenation catalyst. The support is selected from SiO2 or diatomaceous earth. By weight percentage, the nickel content is 5-40%, the cobalt and molybdenum content are 0.2-5.0% respectively, the chromium content is 0.5-6%, the potassium content is 0.5-2%, and the remainder is the support. In the support, pores with a diameter less than 1000 Å account for 5-15% of the pore size distribution. The catalyst has a lower operating temperature and pressure, good applicability, and a long service life. However, its drawback is that it requires the use of chromium, which may cause pollution problems due to dichromates, chromates, and chromium compounds.

[0004] Therefore, developing liquid-phase hydrogenation catalysts that balance catalytic performance with environmental benefits remains a crucial area requiring continuous effort and innovation from engineers. In light of this, the technical solution of this invention is proposed. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides an octenal liquid-phase hydrogenation catalyst and its preparation method. The preparation process of this catalyst does not require the use of substances that may cause water pollution, such as dichromates, chromates, and chromium compounds, making it more environmentally friendly. Furthermore, the prepared catalyst exhibits good catalytic performance and is suitable for use at appropriate temperatures and pressures.

[0006] The basic concept of the technical solution of this invention is as follows:

[0007] A method for preparing an octenal liquid-phase hydrogenation catalyst includes the following steps:

[0008] (1) Prepare a salt solution containing nickel ions, copper ions and aluminum ions, heat it to 40-80℃, add an alkaline precipitant to react, and then age it after the reaction is complete.

[0009] (2) Mix the precipitate obtained after aging in step (1) with silica sol evenly to obtain a slurry;

[0010] (3) The slurry is washed and filtered, and then alkali metal carbonate powder and boron nitride solid are added and mixed. Then it is shaped, dried and calcined to obtain the octenal liquid-phase hydrogenation catalyst.

[0011] In one embodiment, the octenal liquid-phase hydrogenation catalyst contains 8%–15% nickel, 1%–4% copper, and 0.5%–3% alkali metals, with the balance being a composite support of silica, alumina, and boron nitride.

[0012] In one embodiment, the octenal liquid-phase hydrogenation catalyst contains 8%–12% nickel, 2%–3% copper, and 1%–2% alkali metals, with the balance being a composite support of silicon dioxide, aluminum oxide, and boron nitride.

[0013] In one embodiment, the mass ratio of silicon dioxide, aluminum oxide and boron nitride in the composite carrier is 10:(2-7):(0.05-1).

[0014] In one embodiment, the alkali metal carbonate is one or a combination of two of sodium carbonate or potassium carbonate.

[0015] In one embodiment, the roasting temperature is 450–680°C and the time is 2–5 hours.

[0016] In one embodiment, the boron nitride solid is hexagonal boron nitride.

[0017] In one embodiment, the silica sol is a low-sodium or sodium-free silica sol.

[0018] The present invention further provides an octenal liquid-phase hydrogenation catalyst, which is obtained according to any one of the preparation methods described above.

[0019] Compared with the prior art, the present invention has the following advantages:

[0020] 1. The preparation method of the catalyst of the present invention is simple and does not require complicated and demanding operations, which is convenient for industrial production. Moreover, it does not require the use of substances that are prone to pollution, such as dichromates, chromates, and chromium compounds, making it green and environmentally friendly.

[0021] 2. The octenal liquid-phase hydrogenation catalyst of the present invention has high selectivity and conversion rate, and has good catalytic performance. Moreover, it can achieve 100% conversion rate and more than 95% alcohol selectivity at 4MPa and 130℃, and the operating conditions are relatively mild.

[0022] 3. The main raw materials used in the octenal liquid-phase hydrogenation catalyst of the present invention are readily available and inexpensive, which can reduce costs and improve the economic benefits of enterprises. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0024] The raw materials used in the following examples are general commodities purchased from the market. The specific type of raw material (such as the specific type of salt of nickel ions, copper ions and aluminum ions) can be selected according to the ease of acquisition, price and cost, etc., without affecting the effect of the present invention.

[0025] The precipitant can be one of NaOH, Na2CO3, KOH, K2CO3, or ammonia water.

[0026] The calcination temperature is 450–680℃, and the time is 2–5 hours. Good results can be achieved under these conditions, and the specific data in the case study is not the only feasible solution.

[0027] Before use, the octenal liquid-phase hydrogenation catalyst is reduced in hydrogen. The reduction conditions in hydrogen are: reduction temperature of 400–550℃, pressure of 1.5–2.5 MPa, hydrogen:catalyst volume ratio of 250–800:1, and reduction time of 2.5–4 h. Good results can be achieved under these conditions. However, the specific data in the case study are not the only feasible solution.

[0028] In the composite carrier described in this invention, the preferred mass ratio of silicon dioxide, aluminum oxide, and boron nitride is 10:(2-7):(0.05-1). The specific amounts of silica sol, aluminum salt, and boron nitride can be calculated using the principle of atomic conservation and can be weighed according to the specific type of raw materials used.

[0029] The boron nitride solid used in the following examples is hexagonal boron nitride, and the silica sol is JA-25 type silica sol. These are just examples.

[0030] The octenal liquid-phase hydrogenation catalyst of the present invention can be formed into strips, flakes, or spherical particles, wherein the specific embodiment below is formed into spherical particles with a particle size of 5 mm.

[0031] Examples 1-4

[0032] The following method is used to prepare the octenal liquid-phase hydrogenation catalyst, and the specific steps are as follows:

[0033] (1) Weigh out nickel salt, copper salt and aluminum salt according to the formula in Table 1, prepare a salt solution containing nickel ion, copper ion and aluminum ion, heat to 80℃, add alkaline precipitant NaOH to react until there is basically no increase in precipitate (the precipitation is basically completed within 30-50 min), and after the reaction is completed, age at 75-80℃ for 30-40 min.

[0034] (2) Mix the precipitate obtained after aging in step (1) with JA-25 silica sol evenly to obtain a slurry;

[0035] (3) The slurry is washed and filtered, and then alkali metal carbonate powder (sodium carbonate and / or potassium carbonate, as shown in Table 1) and boron nitride solid are added and mixed. Then it is shaped, dried and calcined to obtain the octenal liquid-phase hydrogenation catalyst. The calcination conditions are 680°C and the time is 2h.

[0036] The component formulations of the catalysts in Examples 1-4 (abbreviated as Examples 1-4) are shown in Table 1. The corresponding raw materials should be weighed according to the formulation. In specific operations, 100g of octenal liquid-phase hydrogenation catalyst is used as an example to prepare the catalyst.

[0037] Table 1

[0038]

[0039] Example 5

[0040] The difference from Example 1 is that the active element composition is: 12% nickel, 2% copper, 1% potassium, with the balance being a composite carrier of silicon dioxide, aluminum oxide and boron nitride, while the others remain unchanged.

[0041] Example 6

[0042] The difference from Example 1 is that the active element composition is: 10% nickel, 3% copper, 2% potassium, with the balance being a composite carrier of silicon dioxide, aluminum oxide and boron nitride, while the others remain unchanged.

[0043] Example 7

[0044] The difference from Example 1 is that the calcination conditions are 450°C and the time is 5 hours, while other conditions remain unchanged.

[0045] Comparative Example 1

[0046] The difference from Example 1 is that step (3) in the preparation method does not use solid boron nitride, and there is no solid boron nitride in the composite carrier, while the rest remains the same.

[0047] Comparative Example 2

[0048] The difference from Example 1 is that there are no aluminum ions in step (1) of the preparation method, and there is no aluminum oxide in the composite carrier, while the rest remains the same.

[0049] Comparative Example 3

[0050] The difference from Example 1 is that alkali metal carbonate powder is not added in step (3) of the preparation method, and the active elements do not include alkali metal elements, while the rest remains the same.

[0051] Example of effect

[0052] Equal amounts of the octenal liquid-phase hydrogenation catalysts prepared according to Examples 1-7 and Comparative Examples 1-3 were reduced in hydrogen. The reduction conditions were: reduction temperature 400℃, pressure 2.5MPa, hydrogen:catalyst volume ratio 250:1, and reduction time 4h.

[0053] The reduced catalyst was loaded into a stainless steel single-tube reactor, purged with nitrogen, then pressurized to 4 MPa with hydrogen, heated to 130°C, and held at that temperature and pressure for 24 hours before feeding. The feed rate was 450 ml / hr, octenal was 90 ml / hr, the circulating crude product rate was 460 ml / hr, and the liquid hourly space velocity (LISH) of octenal was 0.2 hr. -1 The conversion rate and alcohol selectivity were evaluated, and the results are shown in Table 2.

[0054] Table 2

[0055] Catalyst number Conversion rate % Selectivity % Example 1 100 97.5 Example 2 100 96.9 Example 3 100 97.6 Example 4 100 97.7 Example 5 100 98.9 Example 6 100 98.6 Example 7 100 97.0 Comparative Example 1 92.1 88.5 Comparative Example 2 89.0 76.9 Comparative Example 3 90.5 81.6

[0056] In addition, the alkenyl liquid-phase hydrogenation catalysts of Examples 1-7 of this invention, after continuous operation for 500 hours, show a conversion rate fluctuation of no more than 0.1% and a selectivity fluctuation of no more than 0.25%, demonstrating stable performance and durability. This reduces the frequency of replacement and saves on production line operating costs.

[0057] While the embodiments disclosed in this invention are as described above, the content is merely for the purpose of facilitating understanding of the invention and is not intended to limit the invention. Any person skilled in the art to which this invention pertains may make any modifications and changes to the form and details of the implementation without departing from the spirit and scope disclosed herein; however, the scope of patent protection of this invention shall still be determined by the scope defined in the appended claims.

Claims

1. A method for preparing an octene aldehyde liquid phase hydrogenation catalyst, comprising the following steps: (1) preparing a salt solution containing nickel ions, copper ions and aluminum ions, heating to 40-80℃, adding a basic precipitant for reaction, and after the reaction is completed, aging; (2) mixing the precipitate obtained after aging in step (1) with silica sol uniformly to obtain a slurry; (3) washing and filtering the slurry, then adding alkali metal carbonate powder and boron nitride solid, mixing uniformly, and then shaping, drying and calcining to obtain the octene aldehyde liquid phase hydrogenation catalyst; In the octene aldehyde liquid phase hydrogenation catalyst, the mass fraction of nickel is 8-15%, the mass fraction of copper is 1-4%, the mass fraction of alkali metal is 0.5-3%, and the balance is a composite carrier of silica, alumina and boron nitride; In the composite carrier, the mass ratio of silica, alumina and boron nitride is 10: (2-7) : (0.05-1).

2. The process for preparing an octene aldehyde liquid phase hydrogenation catalyst according to claim 1, characterized in that, In the octene aldehyde liquid phase hydrogenation catalyst, the mass fraction of nickel is 8-12%, the mass fraction of copper is 2-3%, the mass fraction of alkali metal is 1-2%, and the balance is a composite carrier of silica, alumina and boron nitride.

3. The process for preparing an octene aldehyde liquid phase hydrogenation catalyst according to claim 1, characterized in that, The alkali metal carbonate is one of sodium carbonate or potassium carbonate or a combination of both.

4. The process for preparing an octene aldehyde liquid phase hydrogenation catalyst according to claim 1, characterized in that, The calcination temperature is 450-680℃, and the time is 2-5h.

5. The process for preparing an octene aldehyde liquid phase hydrogenation catalyst according to claim 1, characterized in that, The boron nitride solid is hexagonal boron nitride.

6. The process for preparing an octene aldehyde liquid phase hydrogenation catalyst according to claim 1, characterized in that, The silica sol is low-sodium or sodium-free silica sol.

7. An octene aldehyde liquid phase hydrogenation catalyst characterized by, The preparation method according to any one of claims 1-6.

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