CN103483130B - Method for synthesizing 1,3-butadiene by adopting Bi/Mo/La/Fe four-component composite oxide catalyst - Google Patents

Abstract

The invention discloses a method for synthesizing 1,3-butadiene by using Bi/Mo/La/Fe four-component composite oxide catalyst. In the invention, the prepared four-component composite oxide catalyst is placed in a reactor, and mixed gas is introduced into the reactor, and the reaction is carried out while maintaining a certain space velocity and catalyst bed temperature to obtain a 1,3-butadiene product. More specifically, Bi, Mo, La, Fe and deionized water are used in a certain molar ratio to adjust the pH value of the lye, after concentration, filtration, drying, roasting, cooling, and then grinding and sieving to obtain Bi/ Mo/La/Fe four-component composite oxide catalyst. Different from traditional bismuth-molybdenum catalysts: according to the present invention, high activity and high selectivity Bi/Mo/La for 1,3-butadiene preparation process can be obtained by adjusting the content of metal lanthanum and iron in the catalyst /Fe four-component composite oxide catalyst.

Description

Method for synthesizing 1,3-butadiene with Bi/Mo/La/Fe four-component composite oxide catalyst

technical field

The invention belongs to the technical field of chemistry and chemical engineering, and in particular relates to a method for synthesizing 1,3-butadiene with a Bi/Mo/La/Fe four-component composite oxide catalyst.

Background technique

1,3-butadiene is one of the basic raw materials of petrochemical industry, and its position in petrochemical olefin raw materials is second only to ethylene and propylene. It is mainly used as a general raw material for the production of various synthetic rubbers, polymer resins and chemical intermediates. Among them, the largest use of butadiene is the production of styrene butadiene rubber and polybutadiene rubber, which are mainly used in tire products. Butadiene is also one of the components used in the manufacture of acrylonitrile-butadiene-styrene, styrene-butadiene copolymer latex, styrene-butadiene block copolymer and nitrile rubber. As a synthetic rubber monomer, the amount of butadiene accounts for about 60% of the consumption of all synthetic rubber raw materials. Therefore, the processing and utilization level of butadiene is another important indicator of the development level of the entire petrochemical industry.

Butadiene is mainly extracted from the mixed _C4 fraction produced by ethylene cracking unit in industry. In addition, butadiene can also be produced from the refinery _C4 fraction as a raw material by dehydrogenation. The typical process of butene dehydrogenation to butadiene is Petro-Tex's Oxo-D process. The per-pass conversion rate of butene is ~65%, the selectivity of butadiene is 93%, and the single-pass yield of butadiene is ~60%. Compared with the dehydrogenation method, the extraction method is cheaper and easier to obtain butadiene.

In recent years, with the rising oil price and the rapid development of the automobile industry, the demand for rubber has increased sharply and the production of natural rubber has decreased, resulting in the continuous growth of the market demand for butadiene. The gap between the production of butadiene and the demand for butadiene from the mixed C ₄ fraction produced by the by-product of the ethylene cracking unit will increase day by day. Therefore, in addition to obtaining butadiene from the naphtha cracking route, the use of C ₄ The process route of distillate oxidative dehydrogenation to produce butadiene has also begun to receive widespread attention.

Contents of the invention

The purpose of the present invention is to address the deficiencies in the prior art and provide a method for synthesizing 1,3-butadiene with a Bi/Mo/La/Fe four-component composite oxide catalyst. The catalyst is Bi-Mo-La- The Fe four-component composite metal oxide catalyst has good catalytic activity and selectivity.

The technical solution adopted by the present invention to solve its technical problems is as follows.

The prepared four-component composite oxide catalyst is placed in a reactor, the mixed gas is introduced into the reactor, and the reaction is carried out while maintaining a certain space velocity and catalyst bed temperature to obtain 1,3-butadiene product.

The mixed gas includes 1-butene, air and water vapor, and the mixed volume ratio is 1:3～5:5～16;

The said certain space velocity is 219-438h ^-1 , and the catalyst bed temperature is set at 380-450°C.

In the method for preparing 1,3-butadiene using a four-component composite oxide catalyst, 1-butene is used as the raw material gas in the experiment, and n-butene or C ₄ mixture can also be used in industrial applications.

The four-component composite oxide catalyst components include Bi, Mo, La and Fe, wherein the molar ratio of molybdenum to bismuth is 1:1, the molar ratio of lanthanum to bismuth is 0.01-2:1, and the molar ratio of iron to bismuth is 0.01 ~1.5:1.

In the catalyst, the molar ratio of lanthanum to bismuth is preferably 0.1˜1:1.

In the catalyst, the molar ratio of iron to bismuth is 0.1-0.8:1.

In the catalyst, bismuth is derived from bismuth salt, and the bismuth salt is bismuth nitrate; molybdenum is derived from molybdenum salt, and the molybdenum salt is ammonium molybdate; lanthanum is derived from lanthanum salt, and the lanthanum salt is lanthanum nitrate; iron is derived from iron salt , the iron salt is ferric nitrate.

The preparation process of the four-component composite oxide catalyst comprises the following steps:

Step (1) dispose iron salt of certain quality, lanthanum salt and deionized water in the container, molybdenum salt and deionized water are disposed in another container, wherein bismuth salt is dissolved in the nitric acid solution containing certain concentration, will contain Add the solution of iron salt and lanthanum salt dropwise to the solution containing molybdenum salt, and then add the solution containing bismuth salt dropwise to the above mixed solution after fully stirring, so that the molar ratio of molybdenum to bismuth is 1:1 , The molar ratio of lanthanum to bismuth is 0.1-1:1, and the molar ratio of iron to bismuth is 0.1-0.8:1.

The molar ratio of the mixture of a certain mass of lanthanum salt and iron salt to deionized water is 1:10-100;

The ratio of the molybdenum salt to deionized water is 1:10-100;

The concentration of the nitric acid solution is 5%-50%; the molar ratio of bismuth salt and nitric acid in the nitric acid solution is 1:5-50.

Step (2) Place the above mixed solution in a water bath at 50-70°C, and add ammonia water of a certain concentration drop by drop to adjust the pH;

The mass fraction of the ammonia solution is 25%; the adjusted pH value is 3-7;

Step (3) After stirring the solution in step (2) until viscous, transfer it to an oven for drying.

The oven temperature during the drying is 60-150°C; the drying time is 12-36 h;

The solid obtained in step (4) is calcined, cooled, ground and sieved to obtain a four-component catalyst of 40-60 mesh.

The calcination temperature is 300-700° C., and the calcination time is 2-6 hours.

Beneficial effects of the present invention:

The present invention adopts co-precipitation method, and catalyst preparation uses Bi(NO ₃ ) ₃ 5H ₂ O, (NH ₄ ) ₂ Mo ₇ O ₂₄ 4H ₂ O, La(NO ₃ ) 6H ₂ O and Fe(NO ₃ ) · 9H ₂ O was used as the precursor to prepare La and Fe element-modified bismuth-molybdenum catalysts, which had high activity and selectivity. Using the catalyst to prepare 1,3-butadiene by oxidative dehydrogenation of 1-butene has a selectivity as high as over 92%, and the yield of butadiene can reach over 63%.

Specific implementation method

The present invention will be described in further detail below by way of examples. However, the examples do not constitute a limitation of the invention.

Example 1

Catalyst preparation process

Dissolve 9.7g Bi(NO ₃ ) ₃ ·5H ₂ O in 50mL of 10% nitric acid solution, this solution is designated as solution A. In a water bath at 60°C, mix 0.87g La(NO ₃ )·6H ₂ O and 0.81g Fe(NO ₃ )·9H ₂ O was dissolved in 200mL deionized water, and this solution was designated as solution B. In a water bath at 60°C, 3.53g (NH ₄ ) ₂ Mo ₇ O ₂₄ ·4H ₂ O was dissolved in 200mL In deionized water, this solution is denoted as solution C, in which the molar ratio of molybdenum to bismuth is 1:1, the molar ratio of lanthanum to bismuth is 0.1:1, and the molar ratio of iron to bismuth is 0.1:1. Add solution B dropwise to solution C, after fully stirring; add solution A dropwise to the above mixed solution, after fully stirring, add ammonia solution with a mass fraction of 25% dropwise in the mixed solution, adjust The pH value is 4. After the dropwise addition, continue to stir in a water bath at 60°C until viscous, transfer the viscous material to a drying oven at 60°C for drying, and bake at 550°C for 2 hours in a tube furnace with an oxygen atmosphere. , ground after cooling, and sieved to obtain a four-component bismuth-molybdenum catalyst of 40-60 mesh, which was recorded as BiMoLa _0.1 Fe _0.1 , and kept in a sealed container.

Oxidative Dehydrogenation Process

1.5 mL of the above catalyst was filled into a stainless steel reactor with an inner diameter of 8 mm, and 1-butene was used as the raw material gas, and its percentage content was 99.9%. Simultaneously feed air and water vapor, the composition of which is set to be 1-butene:air:mole ratio of water vapor is 1:4:10, the mixed gas is introduced into the reactor, the space velocity is 327h ^-1 , the catalyst bed Layer temperature is 440 ℃ to react, gas chromatography analysis 2h, the product reaction result after 10h is as follows:

.

Example 2

Catalyst preparation process

Dissolve 9.7g Bi(NO ₃ ) ₃ ·5H ₂ O _in 50mL of 10% nitric acid solution, this _solution is denoted as A solution. g Fe(NO ₃ )·9H ₂ O was dissolved in 200 mL of deionized water, and this solution was designated as solution B. In a water bath at 70°C, 3.53 g of (NH ₄ ) ₂ Mo ₇ O ₂₄ ·4H ₂ O was dissolved in 200 mL of deionized water. In ionized water, this solution is denoted as solution C, in which the molar ratio of molybdenum to bismuth is 1:1, the molar ratio of lanthanum to bismuth is 0.1:1, and the molar ratio of iron to bismuth is 0.8:1. Add solution B dropwise to solution C, after fully stirring; add solution A dropwise to the above mixed solution, after fully stirring, add ammonia solution with a mass fraction of 25% dropwise in the mixed solution, adjust The pH value is 5. After the dropwise addition, continue to stir in a water bath at 70°C until viscous, transfer the viscous material to a drying oven at 60°C for drying, and bake at 500°C for 2 hours in a tube furnace with an oxygen atmosphere. , ground after cooling, and sieved to obtain a four-component bismuth-molybdenum catalyst of 40-60 meshes, which was recorded as BiMoLa _0.1 Fe _0.8 , and kept in a sealed container.

Oxidative Dehydrogenation Process

1.5 mL of the above catalyst was filled into a stainless steel reactor with an inner diameter of 8 mm, and 1-butene was used as the raw material gas, and its percentage content was 99.9%. Simultaneously feed air and water vapor, the composition of which is set to 1-butene:air:molar ratio of water vapor is 1:4:5, the mixed gas is introduced into the reactor, the space velocity is 436h ^-1 , the catalyst bed Layer temperature is 440 ℃ to react, gas chromatography analysis 2h, the product reaction result after 10h is as follows:

.

Example 3

Catalyst preparation process

Dissolve 9.7g Bi(NO ₃ ) ₃ ·5H ₂ O in 50mL of 10% nitric acid solution, this solution is designated as solution A. In a water bath at 60°C, mix 2.60g La(NO ₃ )·6H ₂ O and 4.85g Fe(NO ₃ )·9H ₂ O was dissolved in 200mL deionized water, and this solution was designated as solution B. In a water bath at 60°C, 3.53g (NH ₄ ) ₂ Mo ₇ O ₂₄ ·4H ₂ O was dissolved in 200mL In deionized water, this solution is denoted as solution C, wherein the molar ratio of molybdenum to bismuth is 1:1, the molar ratio of lanthanum to bismuth is 0.3:1, and the molar ratio of iron to bismuth is 0.6:1. Add solution B dropwise to solution C, after fully stirring; add solution A dropwise to the above mixed solution, after fully stirring, add ammonia solution with a mass fraction of 25% dropwise in the mixed solution, adjust The pH value is 5. After the dropwise addition, continue to stir in a water bath at 60°C until viscous, transfer the viscous material to a drying oven at 60°C for drying, and bake at 550°C for 2 hours in a tube furnace with an oxygen atmosphere. , ground after cooling, and sieved to obtain a four-component bismuth-molybdenum catalyst of 40-60 mesh, which was recorded as BiMoLa _0.3 Fe _0.6 , and sealed for storage.

Oxidative Dehydrogenation Process

1.5 mL of the above catalyst was filled into a stainless steel reactor with an inner diameter of 8 mm, and 1-butene was used as the raw material gas, and its percentage content was 99.9%. Simultaneously feed air and water vapor, the composition of which is set to be 1-butene:air:mole ratio of water vapor is 1:4:10, the mixed gas is introduced into the reactor, the space velocity is 327h ^-1 , the catalyst bed Layer temperature is 440 ℃ to react, gas chromatography analysis 2h, the product reaction result after 10h is as follows:

.

Example 4

Catalyst preparation process

Dissolve 9.7g Bi(NO ₃ ) ₃ ·5H ₂ O in 50mL of 10% nitric acid solution, this solution is designated as solution A, in a water bath at 60°C, mix 5.20g La(NO ₃ )·6H ₂ O and 1.62g Fe(NO ₃ )·9H ₂ O was dissolved in 200mL deionized water, and this solution was designated as solution B. In a water bath at 60°C, 3.53g (NH ₄ ) ₂ Mo ₇ O ₂₄ ·4H ₂ O was dissolved in 200mL In deionized water, this solution is denoted as solution C, in which the molar ratio of molybdenum to bismuth is 1:1, the molar ratio of lanthanum to bismuth is 0.6:1, and the molar ratio of iron to bismuth is 0.2:1. Add solution B dropwise to solution C, after fully stirring; add solution A dropwise to the above mixed solution, after fully stirring, add ammonia solution with a mass fraction of 25% dropwise in the mixed solution, adjust The pH value is 5. After the dropwise addition, continue to stir in a water bath at 60°C until viscous, transfer the viscous material to a drying oven at 60°C for drying, and bake at 550°C for 2 hours in a tube furnace with an oxygen atmosphere. , ground after cooling, and sieved to obtain a four-component bismuth-molybdenum catalyst of 40-60 mesh, which was recorded as BiMoLa _0.6 Fe _0.2 , and kept in a sealed container.

Oxidative Dehydrogenation Process

1 mL of the above catalyst was filled into a stainless steel reactor with an inner diameter of 8 mm, and 1-butene was used as the raw material gas, and its percentage was 99.9%. Simultaneously feed air and water vapor, the composition of which is set to 1-butene:air:molar ratio of water vapor is 1:4:5, the mixed gas is introduced into the reactor, the space velocity is 436h ^-1 , the catalyst bed Layer temperature is 440 ℃ to react, gas chromatography analysis 2h, the product reaction result after 10h is as follows:

.

Example 5

Catalyst preparation process

Dissolve 9.7g Bi(NO ₃ ) ₃ ·5H ₂ O in 50mL of 10% nitric acid solution, this solution is denoted as solution A, in a water bath at 60℃, mix 8.66g La(NO ₃ )·6H ₂ O and 0.81g Fe(NO ₃ )·9H ₂ O was dissolved in 200mL deionized water, and this solution was designated as solution B. In a water bath at 60°C, 3.53g (NH ₄ ) ₂ Mo ₇ O ₂₄ ·4H ₂ O was dissolved in 200mL In deionized water, this solution is denoted as solution C, wherein the molar ratio of molybdenum to bismuth is 1:1, the molar ratio of lanthanum to bismuth is 1:1, and the molar ratio of iron to bismuth is 0.1:1. Add solution B dropwise to solution C, after fully stirring; add solution A dropwise to the above mixed solution, after fully stirring, add ammonia solution with a mass fraction of 25% dropwise in the mixed solution, adjust The pH value is 5. After the dropwise addition, continue to stir in a water bath at 60°C until viscous, transfer the viscous material to a drying oven at 60°C for drying, and bake at 550°C for 2 hours in a tube furnace with an oxygen atmosphere. , ground after cooling, and sieved to obtain a 40-60 mesh four-component bismuth-molybdenum catalyst, which was recorded as BiMoLaFe _0.1 , and sealed for storage.

Oxidative Dehydrogenation Process

1 mL of the above catalyst was filled into a stainless steel reactor with an inner diameter of 8 mm, and 1-butene was used as the raw material gas, and its percentage was 99.9%. Air and water vapor are introduced at the same time, the composition of which is set to be 1-butene:air:water vapor molar ratio of 1:4:15, the mixed gas is introduced into the reactor, the space velocity is 436h ^-1 , the catalyst bed Layer temperature is 440 ℃ to react, gas chromatography analysis 2h, the product reaction result after 10h is as follows:

.

Example 6

Catalyst preparation process

Dissolve 9.7g Bi(NO ₃ ) ₃ ·5H ₂ O in 50mL of 10% nitric acid solution, this solution is denoted as solution A. In a water bath at 60℃, 8.66g La(NO ₃ )·6H ₂ O and 6.46 g Fe(NO ₃ )·9H ₂ O was dissolved in 200mL deionized water, and this solution was designated as solution B. In a water bath at 60°C, 3.53g (NH ₄ ) ₂ Mo ₇ O ₂₄ ·4H ₂ O was dissolved in In ionized water, this solution is recorded as C solution, in which the molar ratio of molybdenum to bismuth is 1:1, the molar ratio of lanthanum to bismuth is 1:1, and the molar ratio of iron to bismuth is 0.8:1. Add solution B dropwise to solution C, after fully stirring; add solution A dropwise to the above mixed solution, after fully stirring, add ammonia solution with a mass fraction of 25% dropwise in the mixed solution, adjust The pH value is 5. After the dropwise addition, continue to stir in a water bath at 60°C until viscous, transfer the viscous material to a drying oven at 60°C for drying, and bake at 550°C for 2 hours in a tube furnace with an oxygen atmosphere. , ground after cooling, and sieved to obtain a 40-60 mesh four-component bismuth-molybdenum catalyst, which was recorded as BiMoLaFe _0.8 and kept in a sealed container.

Oxidative Dehydrogenation Process

2mL of the above catalyst was filled into a stainless steel reactor with an inner diameter of 8mm, and 1-butene was used as the raw material gas, and its percentage was 99.9%. Simultaneously feed air and water vapor, the composition of which is set to be 1-butene:air:mole ratio of water vapor is 1:5:15, the mixed gas is introduced into the reactor, the space velocity is 218h ^-1 , the catalyst bed Layer temperature is 440 ℃ to react, gas chromatography analysis 2h, the product reaction result after 10h is as follows:

The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments. It cannot be determined that the specific embodiments of the present invention are limited thereto. , and several simple deduction and substitutions can also be made, all of which should be deemed to belong to the scope of protection of the invention patent determined by the submitted claims.

Claims (1)

1. the method for synthesizing 1,3-butadiene with Bi/Mo/La/Fe four-component composite oxide catalyst is characterized in that: placing the prepared four-component composite oxide catalyst in a reactor, introducing a mixed gas into the reactor, and maintaining a certain space velocity and catalyst bed temperature for reaction to obtain a 1,3-butadiene product; The mixed gas includes 1-butene, air and water vapor, and the mixed volume ratio is 1:3～5:5～16; The certain space velocity is set at 219-438h ^-1 , and the temperature of the catalyst bed is set at 380-450°C; The four-component composite oxide catalyst components include Bi, Mo, La and Fe, wherein the molar ratio of molybdenum to bismuth is 1:1, the molar ratio of lanthanum to bismuth is 0.1-1:1, and the molar ratio of iron to bismuth The ratio is 0.1-0.8:1; in the four-component composite oxide catalyst, bismuth is derived from bismuth salt, and the bismuth salt is bismuth nitrate; molybdenum is derived from molybdenum salt, and the molybdenum salt is ammonium molybdate; lanthanum is derived from lanthanum Salt, the lanthanum salt is lanthanum nitrate; iron is derived from iron salt, the iron salt is iron nitrate; The synthesis of described four-component composite oxide catalyst comprises the steps: Step (1) dispose iron salt of certain quality, lanthanum salt and deionized water in the container, molybdenum salt and deionized water are disposed in another container, wherein bismuth salt is dissolved in the nitric acid solution containing certain concentration, will contain Add the solution of iron salt and lanthanum salt dropwise to the solution containing molybdenum salt, and then add the solution containing bismuth salt dropwise to the above mixed solution after fully stirring, so that the molar ratio of molybdenum to bismuth is 1:1 , the molar ratio of lanthanum to bismuth is 0.1 to 1:1, and the molar ratio of iron to bismuth is 0.1 to 0.8:1; Step (2) Place the above mixed solution in a water bath at 50-70°C, and add ammonia water of a certain concentration drop by drop to adjust the pH; Step (3) Stir the solution in step (2) until viscous, then transfer to an oven for drying; After the solid obtained in step (4) is roasted and cooled, it is ground and sieved to obtain a four-component catalyst of 40 to 60 mesh; In the step (1), the molar ratio of the mixture of a certain mass of lanthanum salt and iron salt to deionized water is 1:10-100; the ratio of the molybdenum salt to deionized water is 1:10-100; The concentration of the nitric acid solution is 5% to 50%; the molar ratio of the bismuth salt to the nitric acid solution is 1:5 to 50; The mass fraction of the ammonia solution in the step (2) is 25%; the adjusted pH value is 3 to 7; When drying in the step (3), the oven temperature is 60-150° C., and the drying time is 12-36 hours; In the step (4), the calcination temperature is 300-700° C., and the calcination time is 2-6 hours.