阅读说明：本技术 一种用于1,4-丁炔二醇固定床加氢制备1,4-丁二醇的催化剂及其制备方法和应用 (Catalyst for preparing 1, 4-butanediol by fixed bed hydrogenation of 1, 4-butynediol and preparation method and application thereof ) 是由 荣泽明 王凤阳 马大庆 刘东妮 苏东宁 秦树春 王越 于 2021-02-09 设计创作，主要内容包括：本发明公开了一种用于1,4-丁炔二醇固定床加氢制备1,4-丁二醇的催化剂,所述催化剂为掺杂铌元素的颗粒状雷尼镍；所述催化剂质量百分比：镍为88-98％,铌为0.1-5％,铝为5-10％。包括金属前驱体合金颗粒的制备；使用碱液对金属合金颗粒的活化处理。制备工艺操作简单、催化加氢效果良好。(The invention discloses a catalyst for preparing 1, 4-butanediol by fixed bed hydrogenation of 1, 4-butynediol, wherein the catalyst is granular Raney nickel doped with niobium; the catalyst comprises the following components in percentage by mass: 88-98% of nickel, 0.1-5% of niobium and 5-10% of aluminum. The method comprises the steps of preparing metal precursor alloy particles; and (3) activating the metal alloy particles by using alkali liquor. The preparation process is simple to operate and has good catalytic hydrogenation effect.)

1. A catalyst for catalyzing fixed bed hydrogenation of 1, 4-butynediol to prepare 1, 4-butanediol is characterized in that the catalyst is granular Raney nickel doped with niobium; the catalyst comprises the following components in percentage by mass: 88-97% of nickel, 0.1-5% of niobium and 2-10% of aluminum.

2. The catalyst of claim 1, wherein: used in fixed bed reactors.

3. The method for preparing a catalyst according to claim 1 or 2, characterized in that: the preparation method adopts a hot melting method, and comprises the following specific processes: firstly, mixing nickel ingots and niobium ingots according to a certain mass ratio, and melting the mixture at a high temperature to obtain nickel-niobium alloy ingots; then mixing and melting a nickel-niobium alloy ingot and an aluminum ingot in a certain mass ratio at high temperature, and cooling to obtain an alloy ingot mixed with three elements of nickel, niobium and aluminum; further crushing and sieving to obtain alloy in 1-10mm size.

4. The production method according to claim 3, characterized in that: alkali is used to activate the granular alloy.

5. The preparation method according to claim 4, wherein the activation temperature is 50-100 ℃, the activation time is 10-200 minutes, the alkali in the alkali liquor is at least one selected from barium hydroxide, sodium hydroxide and potassium hydroxide, the concentration of the alkali liquor is 2-40 wt.%, and the weight ratio of the alloy to the alkali in the alkali liquor is 1 (1-10). And washing the activated metal alloy block by using deionized water at the temperature of 40-80 ℃ until the pH of the collected solution is 7-9 to obtain the granular Raney nickel catalyst.

6. Use of a catalyst according to claim 1 or 2 in the fixed bed hydrogenation of 1, 4-butynediol to 1, 4-butanediol.

Technical Field

The invention relates to the field of preparation of Raney nickel catalysts, and particularly relates to a preparation method of a Raney nickel catalyst for preparing 1, 4-butanediol by hydrogenation of 1, 4-butynediol.

Background

1, 4-Butanediol (BDO) is an important basic organic raw material and has important and wide application in the fields of medicine, textile, military industry and the like, and downstream products of the BDO mainly comprise tetrahydrofuran, gamma-butyrolactone, biodegradable plastics, polybutylene succinate and other downstream derivatives.

The Reppe synthesis method is a widely used method for industrially producing BDO, acetylene and formaldehyde are used as raw materials, 1, 4-Butynediol (BYD) is synthesized under the action of a copper catalyst, and the BYD is subjected to catalytic hydrogenation to produce BDO.

BYD hydrogenation is used for preparing BDO in a serial reaction, firstly BYD is hydrogenated to generate 1, 4-butylene glycol (BED), and then the BED is hydrogenated to generate BDO. In the hydrogenation process, BED is isomerized into gamma-hydroxybutyraldehyde (gamma-HALD), the substance can be further subjected to hydrogenolysis to generate 2-butenol, n-butyraldehyde, n-butanol and the like, and the gamma-HALD is subjected to aldol condensation to generate long-chain byproducts, furan and other byproducts. Therefore, the reaction rate of the BED hydrogenation to BDO is increased, the accumulation amount of BED and gamma-HALD in the reaction system is reduced, and the generation of byproducts can be reduced.

It is believed that weak acid centers on the catalyst surface reduce the formation of gamma-HALD byproducts, thereby increasing BDO selectivity. British patent document GB 1242358A adopts Mo modified nickel catalyst to realize hydrogenation of 1, 4-butynediol to prepare 1, 4-butanediol at high temperature and high pressure. The Chinese patent application with the application number of CN201210212109.2 discloses a preparation and activation method of a powder Raney nickel catalyst special for preparing BDO by BYD hydrogenation. When the nickel-aluminum alloy is smelted, 0.1-2 wt% of modified metal X (X is Mg, B, Sr, Cr, S, Ti, La, Sn, W, Mo or Fe) is added, and in a gap type reaction kettle, when the reaction temperature is 50 ℃ and the reaction pressure is 3MPa, the conversion rate of BYD is 98-100%, and the selectivity of BDO is 90-98%

The powder catalyst is mainly applied to a batch reactor, and for a fixed bed reactor, the influence of the strength of the catalyst needs to be examined. The grant number CN 106140196B discloses a hydrogenation catalyst for preparing BDO by BYD hydrogenation and a method for preparing BDO by BYD hydrogenation, and the modified Raney nickel catalyst is obtained by performing impregnation modification treatment on activated metal alloy particles by using a molybdenum salt aqueous solution and has good catalytic activity. However, the catalyst does not take into account the effect of catalytic strength, and the reaction parameters are only laboratory bench results.

The method for preparing the special granular Raney nickel catalyst for the fixed bed by the proper method is sought, the excellent hydrogenation performance of the Raney nickel catalyst can be exerted while the catalyst has certain compressive strength, the combination matching with the fixed bed reactor and the large-tonnage continuous catalytic hydrogenation process of the granular Raney nickel are realized in the BYD catalytic hydrogenation process, the increasing demand of the market on BDO is met, and the method has great and practical significance.

Disclosure of Invention

In view of the above, the invention aims to provide a BYD hydrogenation BDO granular raney nickel catalyst with simple process operation and good catalytic hydrogenation effect, aiming at the defects of low mechanical strength, poor wear resistance, easy pulverization and loss and inapplicability to large-tonnage continuous catalytic hydrogenation of the existing raney nickel catalyst. The catalyst is applied to a fixed bed reactor and comprises active substances with a spongy porous structure, wherein the granular Raney nickel catalyst comprises the following components of NiNbAl, 88-97% of nickel, 0.1-5% of niobium and 2-10% of aluminum.

Preferably, the precursor is a nickel-niobium-aluminum alloy, wherein the content of Ni is 40-45 wt.%, the content of aluminum is 55-60%, and the content of niobium is 0.1-2 wt.%.

Preferably, the granular Raney nickel with different components is obtained by alkali liquor activation treatment and deionized water washing treatment under set conditions.

Preferably, the metal alloy particles have a particle size of 1-10 mm.

Preferably, the alkali liquor is an aqueous sodium hydroxide solution, the aqueous sodium hydroxide solution passes through the metal alloy particles at a set flow rate for activation treatment, wherein the concentration of the aqueous sodium hydroxide solution is 0.1-7 wt.%, and the space velocity of the aqueous sodium hydroxide solution is 10-100h^-1Activation ofThe treatment temperature is between room temperature and 100 ℃, and the activation time is 1 to 10 hours.

Preferably, the alkali liquor is an aqueous solution of sodium hydroxide, the aqueous solution of sodium hydroxide passes through the metal alloy particles at a set flow rate to carry out activation treatment, wherein the concentration of the aqueous solution of sodium hydroxide is 0.7-3 wt%, and the space velocity of the aqueous solution of sodium hydroxide is 10-60h^-1The activation treatment temperature is 40-80 ℃, and the activation time is 2-8 h.

Preferably, the deionized water is used for washing the metal alloy particles until the pH value of the solution is 7-9 and the washing temperature is 40-80 ℃, so as to obtain the granular Raney nickel catalyst.

Detailed Description

The present invention is described in detail below with reference to specific embodiments, but the present invention is not limited to these embodiments, and structural, methodological or functional changes made by those skilled in the art according to the embodiments are included in the scope of the present invention.

The device used in the invention is a fixed bed reaction. Suitable process conditions are: the reaction temperature is between room temperature and 180 ℃, preferably between 60 and 150 ℃; the reaction pressure is normal pressure to 30MPa, preferably 15 to 25 MPa; the mass concentration of the BYD water solution is 10-50%.

Example 1

Respectively weighing 40kg of nickel ingot and 1kg of niobium ingot, placing the nickel ingot and the 1kg of niobium ingot in a medium-frequency induction smelting furnace, sealing the smelting furnace, opening the current, carrying out heat preservation smelting at 1800 ℃ for 60min, pouring smelted alloy water into a cast steel graphite plate, and carrying out casting; putting the nickel-niobium alloy ingot and 40kg of aluminum ingot into a medium-frequency induction smelting furnace again, sealing the smelting furnace, opening the current, carrying out heat preservation smelting at 1500 ℃ for 30min, pouring the smelted alloy water into a cast steel graphite plate, and carrying out secondary casting. Crushing the cooled alloy ingot, and screening the nickel-niobium-aluminum precursor alloy with 3-7 meshes; 30g of metal alloy particles are accurately weighed and placed in a reaction tube with the inner diameter of 8mm, NaOH alkali solution with the concentration of 2.5 wt% is introduced from the bottom of the reaction tube at the speed of 6L/h, passes through a metal alloy particle bed layer and then flows out from the upper part. The bed temperature is 60 ℃, and the activation time is 2 h. And washing with deionized water at 60 ℃ after alkali liquor activation treatment until the pH value of the washed solution is 7-9.

The activated catalyst is filled into a fixed bed reactor filled with 40 wt.% of 1, 4-butynediol solution, the reaction is carried out for 720 hours at the reaction pressure of 25MPa and the reaction temperature of 60 ℃, the total produced BDO product is 20kg, the conversion rate of 1, 4-butynediol is 100 percent, and the selectivity of 1, 4-butanediol is 96.1-98.9 percent.

Example 2

Respectively weighing 38kg of nickel ingot and 0.5kg of niobium ingot, placing the nickel ingot and the 0.5kg of niobium ingot in a medium-frequency induction smelting furnace, sealing the smelting furnace, opening the current, carrying out heat preservation smelting at 1800 ℃ for 60min, pouring smelted alloy water into a cast steel graphite plate, and carrying out casting; putting the nickel-niobium alloy ingot and 42kg of aluminum ingot into a medium-frequency induction smelting furnace again, sealing the smelting furnace, opening the current, carrying out heat preservation smelting at 1500 ℃ for 30min, pouring the smelted alloy water into a cast steel graphite plate, and carrying out secondary casting. Crushing the cooled alloy ingot, and screening the nickel-niobium-aluminum precursor alloy with 3-7 meshes; 30g of metal alloy particles are accurately weighed and placed in a reaction tube with the inner diameter of 8mm, NaOH alkali solution with the concentration of 3 wt% is introduced from the bottom of the reaction tube at the speed of 6L/h, passes through a metal alloy particle bed layer and then flows out from the upper part. The bed temperature is 60 ℃, and the activation time is 2 h. And washing with deionized water at 60 ℃ after alkali liquor activation treatment until the pH value of the washed solution is 7-9.

The activated catalyst is filled into a fixed bed reactor filled with 40 wt.% of 1, 4-butynediol solution, and the reaction is carried out for 720 hours at the reaction pressure of 25MPa and the reaction temperature of 60 ℃, wherein the conversion rate of the 1, 4-butynediol is 100 percent, and the selectivity of the 1, 4-butanediol is 95.8-98.6 percent.

Example 3

Respectively weighing 38kg of nickel ingot and 0.5kg of niobium ingot, placing the nickel ingot and the 0.5kg of niobium ingot in a medium-frequency induction smelting furnace, sealing the smelting furnace, opening the current, carrying out heat preservation smelting at 2000 ℃ for 30min, pouring smelted alloy water into a cast steel graphite plate, and carrying out casting; putting the nickel-niobium alloy ingot and 42kg of aluminum ingot into a medium-frequency induction smelting furnace again, sealing the smelting furnace, opening the current, carrying out heat preservation smelting at 1800 ℃ for 30min, pouring the smelted alloy water into a cast steel graphite plate, and carrying out secondary casting. Crushing the cooled alloy ingot, and screening the nickel-niobium-aluminum precursor alloy with 3-7 meshes; 30g of metal alloy particles are accurately weighed and placed in a reaction tube with the inner diameter of 8mm, NaOH alkali solution with the concentration of 2.5 wt% is introduced from the bottom of the reaction tube at the speed of 8L/h, passes through a metal alloy particle bed layer and then flows out from the upper part. The bed temperature is 80 ℃ and the activation time is 4 h. And washing with deionized water at 60 ℃ after alkali liquor activation treatment until the pH value of the washed solution is 7-9.

The activated catalyst is filled into a fixed bed reactor filled with 40 wt.% of 1, 4-butynediol solution, and the reaction is carried out for 720 hours at the reaction pressure of 25MPa and the reaction temperature of 60 ℃, wherein the conversion rate of the 1, 4-butynediol is 100 percent, and the selectivity of the 1, 4-butanediol is 97.2-99.3 percent.

Example 4

Respectively weighing 38kg of nickel ingot and 0.5kg of niobium ingot, placing the nickel ingot and the 0.5kg of niobium ingot in a medium-frequency induction smelting furnace, sealing the smelting furnace, opening the current, carrying out heat preservation smelting at 2000 ℃ for 30min, pouring smelted alloy water into a cast steel graphite plate, and carrying out casting; putting the nickel-niobium alloy ingot and 42kg of aluminum ingot into a medium-frequency induction smelting furnace again, sealing the smelting furnace, opening the current, carrying out heat preservation smelting at 1800 ℃ for 30min, pouring the smelted alloy water into a cast steel graphite plate, and carrying out secondary casting. Crushing the cooled alloy ingot, and screening the nickel-niobium-aluminum precursor alloy with 2-8 meshes; 30g of metal alloy particles are accurately weighed and placed in a reaction tube with the inner diameter of 8mm, NaOH alkali solution with the concentration of 2.5 wt% is introduced from the bottom of the reaction tube at the speed of 6L/h, passes through a metal alloy particle bed layer and then flows out from the upper part. The bed temperature is 90 ℃ and the activation time is 4 h. And washing with deionized water at 80 ℃ after alkali liquor activation treatment until the pH value of the washed solution is 7-9.

The activated catalyst is filled into a fixed bed reactor filled with 40 wt.% of 1, 4-butynediol solution, and the reaction is carried out for 720 hours at the reaction pressure of 25MPa and the reaction temperature of 60 ℃, wherein the conversion rate of the 1, 4-butynediol is 100 percent, and the selectivity of the 1, 4-butanediol is 96.2-98.5 percent.

Example 5

Respectively weighing 38kg of nickel ingot and 0.5kg of niobium ingot, placing the nickel ingot and the 0.5kg of niobium ingot in a medium-frequency induction smelting furnace, sealing the smelting furnace, opening the current, carrying out heat preservation smelting at 2000 ℃ for 30min, pouring smelted alloy water into a cast steel graphite plate, and carrying out casting; putting the nickel-niobium alloy ingot and 42kg of aluminum ingot into a medium-frequency induction smelting furnace again, sealing the smelting furnace, opening the current, carrying out heat preservation smelting at 1800 ℃ for 30min, pouring the smelted alloy water into a cast steel graphite plate, and carrying out secondary casting. Crushing the cooled alloy ingot, and screening the nickel-niobium-aluminum precursor alloy with 4-8 meshes; 30g of metal alloy particles are accurately weighed and placed in a reaction tube with the inner diameter of 8mm, NaOH alkali solution with the concentration of 2.5 wt% is introduced from the bottom of the reaction tube at the speed of 6L/h, passes through a metal alloy particle bed layer and then flows out from the upper part. The bed temperature is 80 ℃, and the activation time is 2 h. And washing with deionized water at 80 ℃ after alkali liquor activation treatment until the pH value of the washed solution is 7-9.

The activated catalyst is filled into a fixed bed reactor filled with 40 wt.% of 1, 4-butynediol solution, and the reaction is carried out for 1000 hours at the reaction pressure of 25MPa and the reaction temperature of 60 ℃, wherein the conversion rate of the 1, 4-butynediol is 100 percent, and the selectivity of the 1, 4-butanediol is 97.8-99.5 percent. The average particle size of the catalyst after reaction is reduced by not more than 5% compared with that of a fresh catalyst.

Example 6

Respectively weighing 35kg of nickel ingot and 0.5kg of niobium ingot, placing the nickel ingot and the niobium ingot in a medium-frequency induction smelting furnace, sealing the smelting furnace, opening the current, carrying out heat preservation smelting at 2000 ℃ for 30min, pouring smelted alloy water into a cast steel graphite plate, and carrying out casting; putting the nickel-niobium alloy ingot and 45kg of aluminum ingot into a medium-frequency induction smelting furnace again, sealing the smelting furnace, opening the current, carrying out heat preservation smelting at 1800 ℃ for 30min, pouring the smelted alloy water into a cast steel graphite plate, and carrying out secondary casting. Crushing the cooled alloy ingot, and screening the nickel-niobium-aluminum precursor alloy with 4-8 meshes; 30g of metal alloy particles are accurately weighed and placed in a reaction tube with the inner diameter of 8mm, NaOH alkali solution with the concentration of 2.5 wt% is introduced from the bottom of the reaction tube at the speed of 8L/h, passes through a metal alloy particle bed layer and then flows out from the upper part. The bed temperature is 60 ℃, and the activation time is 2 h. And washing with deionized water at 80 ℃ after alkali liquor activation treatment until the pH value of the washed solution is 7-9.

The activated catalyst is filled into a fixed bed reactor filled with 40 wt.% of 1, 4-butynediol solution, and the reaction is carried out for 1000 hours at the reaction pressure of 25MPa and the reaction temperature of 60 ℃, wherein the conversion rate of the 1, 4-butynediol is 100 percent, and the selectivity of the 1, 4-butanediol is 97.6-99.3 percent. The average particle size of the catalyst after reaction is reduced by not more than 5% compared with that of a fresh catalyst.