CN113244928A - Novel catalyst for preparing ethanol by methyl acetate hydrogenation and preparation method thereof - Google Patents

Abstract

The invention discloses a novel catalyst for preparing ethanol by methyl acetate hydrogenation and a preparation method thereof, wherein the catalyst comprises the following components in percentage by mass: SiO 2₂:Cu:CeO₂:La₂O₃= A: B: C: D, wherein B: a is 0.01-70%, C: a is 0.01-10%, D: a is 0.01 to 10%. The method has simple process, obviously reduces the preparation cost of the catalyst, and the obtained catalyst has good activity, good conversion rate of methyl acetate and selectivity of ethanol, and side effectLess products and long service life of the catalyst.

Description

Novel catalyst for preparing ethanol by methyl acetate hydrogenation and preparation method thereof

Technical Field

The invention belongs to the field of catalyst preparation, and relates to a novel catalyst for preparing ethanol by methyl acetate hydrogenation and a preparation method thereof.

Background

Ethanol is a fermentation industrial product with longest production history and largest yield in the world at present, and is widely applied to industries such as food, chemical industry, medicine, dye, national defense and the like. The current popular research route is that coal, natural gas, biomass and the like are gasified to prepare synthesis gas, and then the synthesis gas is used for preparing ethanol. Direct method for preparing ethanol from synthesis gas

And indirect methods, each of which has advantages and disadvantages. The preparation of ethanol by acetic acid hydrogenation is a technology for indirectly preparing ethanol by synthesis gas, firstly, methanol is produced by synthesis gas, the methanol is carbonylated to synthesize acetic acid, and then the acetic acid is directly hydrogenated or esterified and then hydrogenated to prepare ethanol.

In the last 80 s, BASF developed a continuous ethanol production and multi-step distillation technology, in which methyl acetate and acetic acid were synthesized by methanol carbonylation, methyl acetate was separated out and hydrogenated into ethanol by using a copper-based catalyst, and by-products such as acetic acid, methanol and dimethyl ether separated out in different distillation steps were recycled to a oxo reactor. The catalyst and the method for preparing ethanol by hydrogenating methyl acetate are developed by the minification of Jiangsu, the conversion rate of methyl acetate of the developed copper-based catalyst is more than or equal to 80 percent, and the selectivity of ethanol is more than or equal to 95 percent. It is reported that monolithic Cu-SiO is prepared on an array-structured cordierite carrier by a coating method₂The catalyst has high activity, methyl acetate converting rate up to 99.8% and ethanol selectivity up to 95%. In is reported₂O₃Modified Cu-SiO₂The catalyst, although good in performance, is expensive in indium.

A preparation method of a copper-zinc catalyst related to Chinese patent CN201610984400 mainly comprises the following steps: mixing a part by weight of soluble copper salt, a part by weight of soluble zinc salt and a part by weight of starch, grinding for the first time, then adding a part by weight of sodium carbonate and a part by weight of starch, grinding for the second time, washing, drying and calcining to obtain the copper-zinc catalyst. The method takes starch as a pore-forming agent, effectively improves the specific surface area of the copper-zinc catalyst, has high catalytic activity, and has quick, simple and convenient preparation process and good reproducibility. However, the soluble copper salt, the soluble zinc salt and the starch cannot be well mixed due to grinding treatment, so that the reaction is insufficient, and the catalyst cannot fully exert the required catalytic activity.

Chinese patent CN106345469A relates to a dendritic Cu/C-CuSiO₃The preparation of the catalyst is firstly to make the ethyl orthosilicate vinegar pass through the monodisperse carbon nanoThe surface of the rice tube is hydrolyzed to form a silicon dioxide coating layer, then the silicon dioxide coating layer reacts with copper ammonia complex ions under the hydrothermal condition to generate a copper silicate needle array outside the carbon nano tube, and finally metal nano copper particles are loaded on the inner surface and the outer surface of the material to adjust the content of metal copper and copper silicate.

CuO/ZnO/Al related to Chinese patent CN1329938₂O₃Catalyst, CuO/ZnO/Al₂O₃The catalyst is prepared by a coprecipitation method to prepare a coprecipitation precursor containing copper, zinc and aluminum, and a coprecipitation method to prepare a copper and zinc coprecipitation precursor without containing aluminum. Also, the preparation process is complicated and somewhat costly.

Compared with the three patents, the method adopts an ammonia distillation method to prepare the catalyst for preparing the ethanol by hydrogenating methyl acetate, adopts silica gel as a carrier to carry an active component copper, and adds an auxiliary agent La₂O₃、CeO₂ La₂O₃-CeO₂Adding ammonia water into the precipitant, reacting, filtering, drying and roasting to obtain the catalyst for preparing the ethanol by hydrogenating the methyl acetate. The method has simple process, obviously reduces the preparation cost of the catalyst, and the obtained catalyst has good activity, good conversion rate of methyl acetate and selectivity of ethanol, fewer byproducts and long service life.

Disclosure of Invention

The invention provides a novel catalyst for preparing ethanol by methyl acetate hydrogenation and a preparation method thereof, and aims to solve the technical problems of high catalyst preparation cost, low catalyst activity and more byproducts in the prior art.

A novel catalyst for preparing ethanol by hydrogenating methyl acetate comprises the following components in percentage by mass: SiO 2₂: Cu: CeO₂: La₂O₃= A: B: C: D, wherein B: a ranges from 0.01 to 70% (W/W%), C: a ranges from 0.01 to 10% (W/W%), D: a ranges between 0.01 and 10% (W/W%).

The novel catalyst for preparing ethanol by methyl acetate hydrogenation and the preparation method thereof comprise the following steps:

step (1): diluting silica gel in deionized water to obtain a solution with the concentration of 0.01-5 mol/L;

step (2): dissolving nitrate of copper, cerium and/or lanthanum in deionized water to obtain a solution with the concentration of 0.01-5 mol/L;

and (3): measuring a certain amount of strong ammonia water;

and (4): dissolving sodium carbonate in deionized water to obtain a solution with the concentration of 0.01-5 mol/L;

and (5): gradually adding the solution obtained in the step (2) into the solution (1) under heating and stirring, and reacting for 0.1-48 hours;

and (6): gradually adding the solution obtained in the step (4) into the product obtained in the step (5) under heating and stirring, and reacting for 0.1-48 hours;

and (7): gradually adding the solution obtained in the step (3) into the reactant obtained in the step (6), and reacting for 0.1-48 hours;

and (8): filtering the reactant obtained in the step (7) to obtain a filter cake;

and (9): adding water into the filter cake obtained in the step (8), pulping, filtering, repeating for 1-10 times, and filtering to obtain a filter cake;

step (10): drying the filter cake obtained in the step (9) at 60-120 ℃ for 5-24 hours, then heating to 200-600 ℃ in a muffle furnace at a heating rate of 5 ℃/min, roasting for 1-24 hours, and naturally cooling to room temperature;

step (11): crushing, tabletting, crushing and sieving the roasted material obtained in the step (10) to 20-40 meshes, or adding 0.1-20% W/W of carbon and a binder after crushing, extruding or tabletting to obtain the novel catalyst for preparing ethanol by hydrogenating methyl acetate, namely CeO₂-Cu/SiO₂Or La₂O₃-Cu/SiO₂Or CeO₂- La₂O₃-Cu/SiO₂。

The novel catalyst for preparing ethanol by methyl acetate hydrogenation and the preparation method thereof have the advantages of simple preparation process, little environmental pollution and low cost, obviously reduce the preparation cost of the catalyst, and ensure that the activity, the stability, the methyl acetate conversion rate and the ethanol selectivity of the obtained catalyst are superior to those of other reported catalysts for preparing ethanol by methyl acetate hydrogenation in the reaction.

Detailed Description

The following examples are given to illustrate specific embodiments of the present invention, but are not intended to limit the scope of the present invention in any way. The instruments and devices referred to in the following examples are conventional instruments and devices unless otherwise specified; the industrial raw materials are all conventional industrial raw materials which are sold on the market if not specifically indicated; the processing and manufacturing methods are conventional methods unless otherwise specified.

Example 1: a novel catalyst for preparing ethanol by hydrogenating methyl acetate and a preparation method thereof comprise the following steps:

step (1): diluting silica gel in deionized water to obtain a solution with the concentration of 0.01-5 mol/L;

step (2): dissolving nitrates of copper, cerium and lanthanum in deionized water to obtain a solution with the concentration of 2-4 mol/L;

and (3): measuring a certain amount of strong ammonia water;

and (4): dissolving sodium carbonate in deionized water to obtain a solution with the concentration of 1-3 mol/L;

and (5): gradually adding the solution obtained in the step (2) into the solution obtained in the step (1) under heating and stirring, and reacting for 1-8 hours;

and (6): gradually adding the solution obtained in the step (4) into the product obtained in the step (5) under heating and stirring, and reacting for 1-8 hours;

and (7): gradually adding the solution obtained in the step (3) into the reactant obtained in the step (6), and reacting for 1-8 hours;

and (8): filtering the reactant obtained in the step (7) to obtain a filter cake;

and (9): adding water into the filter cake obtained in the step (8), pulping, filtering, repeating for 2-4 times, and filtering to obtain a filter cake;

step (10): drying the filter cake obtained in the step (9) at 70-90 ℃ for 5-24 hours, then heating to 300-500 ℃ at a heating rate of 5 ℃/min, roasting for 2-4 hours, and naturally cooling to room temperature;

step (11): crushing, tabletting, crushing and sieving the roasted material obtained in the step (10) to 20-40 meshes, or adding 3-10% W/W of carbon and a binder after crushing, extruding or tabletting to obtain the novel catalyst for preparing ethanol by hydrogenating methyl acetate, namely CeO₂-Cu/SiO₂Or La₂O₃-Cu/SiO₂Or CeO₂- La₂O₃-Cu/SiO₂。

The catalyst comprises the following components in percentage by mass: SiO 2₂: Cu: CeO₂: La₂O₃= A: B: C: D, wherein B: a is 20-40%, C: a is 2-6%, D: a is 2 to 6 percent.

Example 2: weighing 33.3g of 30wt.% silica gel, and diluting the silica gel in 66.7g of deionized water to obtain a solution with the concentration of 2mol/L, wherein the solution is marked as solution A; weighing Cu (NO)₃)₂·3H₂O 9.5g、Ce(NO₃)₃·6H₂0.5g of O is dissolved in 100mL of deionized water and is marked as solution B; weighing 50ml of concentrated ammonia water, wherein the mass fraction of the concentrated ammonia water is 25-28%, and marking as solution C; weighing Na₂CO₃4.2g of the filtrate was dissolved in 100g of deionized water to obtain solution D. Heating the solution B at 80 ℃, stirring, gradually adding the solution B into the solution A, reacting for 6 hours, gradually adding the solution D into the former reactant, then adding the solution C, reacting for 3 hours, filtering, adding water into the obtained filter cake, pulping, filtering, repeating for 2 times to obtain a filter cake, drying at 60-120 ℃ for 5-24 hours, then heating to 300 ℃ at a heating rate of 5 ℃/min in a muffle furnace, roasting for 4 hours, naturally cooling to room temperature, crushing, tabletting, crushing, and sieving to 20-40 meshes to obtain the novel catalyst for preparing ethanol by hydrogenating methyl acetate, namely the CeO catalyst₂-Cu/SiO₂。

Example 3: weighing 33.3g of 30wt.% silica gel, and diluting the silica gel in 66.7g of deionized water to obtain a solution with the concentration of 2mol/L, wherein the solution is marked as solution A; weighing Cu (NO)₃)₂·3H₂O 9.5g、La(NO₃)₃·6H₂Dissolving 0.5g of O in 100mL of deionized water to obtain solution B; measuring concentrated ammonia50ml of water is marked as solution C; weighing Na₂CO₃4.2g of the filtrate was dissolved in 100g of deionized water to obtain solution D. Heating the solution B at 80 ℃, stirring, gradually adding the solution B into the solution A, reacting for 3 hours, gradually dripping the solution D into a former reactant, adding the solution C, reacting for 3 hours, filtering, adding water into the obtained filter cake, pulping, filtering, repeating for 2 times to obtain a filter cake, drying at 80 ℃ for 5-24 hours, heating to 300 ℃ at a heating rate of 5 ℃/min in a muffle furnace, roasting for 4 hours, naturally cooling to room temperature, crushing, tabletting, crushing, and sieving to 20-40 meshes to obtain the novel catalyst La for preparing the ethanol by hydrogenating the methyl acetate₂O₃-Cu/SiO₂。

Example 4: weighing 33.3g of 30wt.% silica gel, and diluting the silica gel in 66.7g of deionized water to obtain a solution with the concentration of 2mol/L, wherein the solution is marked as solution A; weighing Cu (NO)₃)₂·3H₂O 9.5g、La(NO₃)₃·6H₂O 0.25g、Ce(NO₃)₃·6H₂Dissolving 0.25g of O in 100mL of deionized water to obtain solution B; measuring 50ml of concentrated ammonia water, and marking as solution C; weighing Na₂CO₃4.2g of the filtrate was dissolved in 100g of deionized water to obtain solution D. Heating the solution B at 80 ℃, stirring, gradually adding the solution B into the solution A, reacting for 3 hours, gradually adding the solution D into the former reactant, then adding the solution C, reacting for 3 hours, filtering, adding water into the obtained filter cake, pulping, filtering, repeating for 3 times to obtain a filter cake, drying for 3 hours at 100 ℃, then heating to 400 ℃ at a heating rate of 5 ℃/min in a muffle furnace, roasting for 8 hours, naturally cooling to room temperature, then crushing, tabletting, crushing, and sieving to 20-40 meshes to obtain the novel methyl acetate hydrogenation ethanol catalyst, namely CeO₂- La₂O₃-Cu/SiO₂。

Example 5: the obtained novel catalyst for preparing ethanol by methyl acetate hydrogenation can also be crushed, added with 0.1-20% W/W% carbon and binder, extruded into strips or made into sheets to obtain the novel catalyst for preparing ethanol by methyl acetate hydrogenation, namely CeO₂- La₂O₃-Cu/SiO₂。

The catalysts obtained in example 2, example 3 and example 4 were applied to the production of methyl acetate, and a control group was set, except for the addition of no catalyst in control 1, the conditions were kept consistent, and the reaction formulas were kept at H/MA =50, T =523K, and P =3.0MPa, (detection method) the catalysts obtained in example 1, example 2, example 3 and control 1 were applied to methyl acetate, and the statistical results of the conversion rate of methyl acetate and the selectivity of the catalyst are shown in table 1:

TABLE 1 comparison of catalyst evaluation results

。

Although the present invention has been described in detail with reference to the embodiments, it will be understood by those skilled in the art that various changes in the specific parameters of the embodiments may be made without departing from the spirit of the present invention, and a plurality of specific embodiments are formed, which are common variations of the present invention, and will not be described in detail herein.

Claims (3)

1. A novel catalyst for preparing ethanol by hydrogenating methyl acetate is characterized by comprising the following components in percentage by mass: SiO 2₂: Cu: CeO₂: La₂O₃= A: B: C: D, wherein B: a is 0.01-70%, C: a is 0.01-10%, D: a is 0.01 to 10%.

2. A preparation method of a novel catalyst for preparing ethanol by methyl acetate hydrogenation is characterized in that the catalyst is prepared by adopting an ammonia distillation method.

3. The preparation method of the novel catalyst for preparing ethanol by hydrogenating methyl acetate according to claim 1, characterized by comprising the following steps:

step (1): diluting silica gel in deionized water to obtain a solution with the concentration of 0.01-5 mol/L;

step (2): dissolving nitrate of copper, cerium and/or lanthanum in deionized water to obtain a solution with the concentration of 0.01-5 mol/L;

and (3): measuring ammonia water;

and (4): dissolving sodium carbonate in deionized water to obtain a solution with the concentration of 0.01-5 mol/L;

and (5): gradually adding the solution obtained in the step (2) into the solution obtained in the step (1) under heating and stirring, and reacting for 0.1-48 hours;

and (6): gradually adding the solution obtained in the step (4) into the product obtained in the step (5) under heating and stirring, and reacting for 0.1-48 hours;

and (7): gradually adding the ammonia water obtained in the step (3) into the reactant obtained in the step (6), and reacting for 0.1-48 hours;

and (8): filtering the reactant obtained in the step (7) to obtain a filter cake;

and (9): adding water into the filter cake obtained in the step (8), pulping, filtering, repeating for 1-10 times, and filtering to obtain a filter cake;

step (10): drying the filter cake obtained in the step (9) at 60-120 ℃ for 5-24 hours, then heating to 200-600 ℃ at a heating rate of 5 ℃/min, roasting for 1-24 hours, and naturally cooling to room temperature;

step (11): crushing, tabletting, crushing and sieving the roasted material obtained in the step (10) to 20-40 meshes, or adding 0.1-20% W/W of carbon and a binder after crushing, extruding or tabletting to obtain the novel catalyst for preparing ethanol by hydrogenating methyl acetate, namely CeO₂-Cu/SiO₂Or La₂O₃-Cu/SiO₂Or CeO₂- La₂O₃-Cu/SiO₂。