CN105175207B - Method for synthesizing 1,3-butadiene by Bi/Mo/Co/La/Fe five-component mixed-oxide catalyst moving bed - Google Patents

Abstract

The invention discloses a method for synthesizing 1,3-butadiene with a Bi/Mo/Co/La/Fe five-component composite oxide catalyst moving bed, belonging to the technical field of chemistry and chemical engineering. In the invention, the prepared five-component composite oxide catalyst is placed in a moving bed reactor, and 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 The product, the reaction catalyst is gradually moved to the regeneration reactor, and fresh catalyst is added to the moving bed reactor. In the present invention, Bi, Mo, Co, La, Fe and deionized water are configured according to a certain molar ratio, and the pH value is adjusted by lye. After concentration, filtration, drying, roasting and cooling, the Bi/Mo compound is obtained by grinding and sieving. /Co/La/Fe. Different from the traditional process: according to the present invention, the content of metal Co, La and Fe in the catalyst can be adjusted to obtain a highly active and highly selective five-component composite oxidation process for the preparation of 1,3-butadiene. material catalyst.

Description

Synthesis of 1,3- butadiene method

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/Co/La/Fe five-component composite oxide catalyst moving bed.

Background technique

1,3-Butadiene is an important basic raw material in the petrochemical industry, especially an important raw material monomer for synthetic rubber and resin, and is also widely used in the synthesis of engineering plastics and organic chemical products. At present, there are two main sources of butadiene, one is the extraction method, which is extracted from the mixed C ₄ fraction produced by the ethylene cracking unit; the other is the dehydrogenation method, that is, the C ₄ The distillate is obtained by dehydrogenation. Compared with the dehydrogenation method, the extraction method is cheaper to prepare butadiene, and has become the main method of butadiene production. In recent years, with the rapid development of the automobile industry, the demand for rubber has increased sharply and the production of natural rubber has decreased, resulting in an increasingly strong market demand for butadiene, which has been on the rise for several consecutive years. The process of extracting and producing butadiene from the mixed _C4 fraction produced by the ethylene cracking unit can no longer meet the needs of the market. It also realizes the efficient utilization of C ₄ resources.

In CN103274888B and CN103274887B, the method for preparing 1,3-butadiene using bismuth-molybdenum multi-component catalysts is announced. This series of catalysts is mainly used in fixed-bed reactors. In this catalytic reaction, a large amount of water needs to be introduced to suppress the accumulation of the catalyst. Carbon deactivation, with the current industrial energy-saving requirements, reducing the water content in the reaction process to achieve a low-water or anhydrous oxidative dehydrogenation process is an important direction of industrial research.

Contents of the invention

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

In order to achieve the above object, the technical solution adopted by the present invention is as follows.

The prepared five-component composite oxide catalyst is placed in a moving bed reactor, and 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 a 1,3-butadiene product, The reaction catalyst gradually moves to the regeneration reactor, and at the same time replenishes fresh catalyst to the moving bed reactor; the mixed gas includes 1-butene and air, and its volume ratio is 1:3～6; the certain space velocity is 10～ 50h ^-1 ; the temperature of the catalyst bed is set at 380-450°C; the space velocity of the regeneration reactor is 10-30h ^-1 , and the bed temperature is set at 450-550°C.

The five-component composite oxide catalyst components include Bi, Mo, Co, La and Fe, wherein: the molar ratio of molybdenum to bismuth is 1:1, the molar ratio of cobalt to bismuth is 0.01-2:1, lanthanum to bismuth The molar ratio of iron to bismuth is 0.01 to 1:1, and the molar ratio of iron to bismuth is 0.05 to 1:1; in the catalyst, bismuth is derived from bismuth nitrate, molybdenum is derived from ammonium molybdate, cobalt is derived from cobalt nitrate, and lanthanum is derived from Lanthanum nitrate and iron are derived from ferric nitrate.

The synthesis of described five-component composite oxide catalyst comprises the steps:

(1) according to above-mentioned catalyst component distribution ratio, cobalt salt, lanthanum salt and iron salt of certain quality are dissolved in deionized water and made into mixed salt solution, molybdenum salt is dissolved in deionized water to form molybdenum salt solution, bismuth salt is dissolved in containing In the nitric acid solution of a certain concentration, add the mixed salt solution dropwise to the solution containing the molybdenum salt, and fully stir; then add the bismuth salt dropwise to the above mixed solution;

(2) Place the above solution in a water bath at 50-80°C, add ammonia water with a mass fraction of 25% drop by drop, and adjust the pH to 3-7;

(3) Stir the solution in step (2) until it becomes viscous, then transfer it to an oven for drying, and the obtained solid is roasted, cooled, ground and sieved to obtain a 40-60 mesh five-component composite oxide catalyst.

Further, in the catalyst: the molar ratio of cobalt to bismuth is 0.1-0.6:1, the molar ratio of lanthanum to bismuth is 0.2-0.5:1, and the molar ratio of iron to bismuth is 0.3-0.8:1.

Further, in the synthesis step (3) of the catalyst: the drying temperature is 80-150° C., and the drying time is 10-15 hours; the calcination temperature is 400-700° C., and the calcination time is 2-6 hours.

Compared with prior art, the beneficial effect of the present invention is:

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, Co(NO ₃ ) ₂ ·6H ₂ O, La(NO ₃ ) ₃ ·6H ₂ O and Fe(NO ₃ ) ₃ ·9H ₂ O as precursors to prepare Bi/Mo/Co/La/Fe five-component composite oxide catalyst, which has high activity and selectivity. Using the catalyst to synthesize 1,3-butadiene with a moving bed, the conversion rate is as high as over 80%, and the yield of butadiene can reach over 70%.

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. ) _{3 ·} 6H ₂ O and _2.4g Fe(NO ₃ ) _{3 ·} 9H ₂ O _were dissolved in _200mL deionized water. In 200mL deionized water, this solution is recorded as solution C, wherein the molar ratio of molybdenum to bismuth is 1:1, the molar ratio of cobalt to bismuth is 0.1:1, the molar ratio of lanthanum to bismuth is 0.2:1, and the molar ratio of iron to bismuth is 0.2:1. The molar ratio of bismuth is 0.3:1. In a water bath at 50°C, add B dropwise to C and stir well. Add A dropwise to the above mixed solution, after fully stirring, dropwise add ammonia solution with a mass fraction of 25% in the mixed solution of five kinds of salts, adjust the pH value to 3, after the dropwise addition, continue to Stir in a water bath at 50°C until viscous, transfer the viscous material to a drying oven at 80°C to dry for 15 hours, bake in a tube furnace with an oxygen atmosphere at 700°C for 2 hours, grind after cooling, and sieve to obtain 40-60 The purpose is five-component bismuth molybdenum lanthanum catalyst, the catalyst is recorded as BiMoCo _0.1 La _0.2 Fe _0.3 , and it is sealed and stored.

Oxidative Dehydrogenation Process

1.5 mL of the above-mentioned catalyst was filled into a moving bed reactor with an inner diameter of 8 mm, and 1-butene was used as a raw material gas, and its percentage content was 99.9%. At the same time, air was introduced, and the composition was set as 1-butene: air molar ratio was 1:3, and the mixed gas was introduced into the reactor with a space velocity of 10h ^-1 and a catalyst bed temperature of 450°C for reaction. The reaction catalyst is gradually moved to the regeneration reactor, while fresh catalyst is replenished into the moving bed reactor. The space velocity of the regeneration reactor was 10h ^-1 , and the bed temperature of the regeneration reactor was set at 550°C. 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. ) _{3 ·} 6H ₂ O and _6.5g Fe(NO ₃ ) _{3 ·} 9H ₂ O _were dissolved in _200mL deionized water. In 200mL deionized water, this solution is recorded as solution C, wherein the molar ratio of molybdenum to bismuth is 1:1, the molar ratio of cobalt to bismuth is 0.6:1, the molar ratio of lanthanum to bismuth is 0.5:1, and the molar ratio of iron to bismuth is 0.5:1. The molar ratio of bismuth is 0.8:1. In a water bath at 80°C, add B dropwise to C and stir well. Add A dropwise to the above mixed solution, after fully stirring, dropwise add ammonia solution with a mass fraction of 25% in the mixed solution of five kinds of salts, adjust the pH value to 7, after the dropwise addition, continue to Stir in a water bath at 80°C until viscous, transfer the viscous material to a drying oven at 150°C to dry for 6 hours, roast in a tube furnace with an oxygen atmosphere at 400°C for 6 hours, grind after cooling, and sieve to obtain 40-60 Objective five-component bismuth molybdenum lanthanum catalyst, catalyst is denoted as

BiMoCo _0.6 La _0.5 Fe _0.8 , airtight storage.

Oxidative Dehydrogenation Process

1.5 mL of the above-mentioned catalyst was filled into a moving bed reactor with an inner diameter of 8 mm, and 1-butene was used as a raw material gas, and its percentage content was 99.9%. At the same time, air was introduced, and the composition was set as 1-butene: air molar ratio was 1:6, and the mixed gas was introduced into the reactor with a space velocity of 50h ^-1 and a catalyst bed temperature of 380°C for reaction. The reaction catalyst is gradually moved to the regeneration reactor, while fresh catalyst is replenished into the moving bed reactor. The space velocity of the regeneration reactor was 30h ^-1 , and the bed temperature of the regeneration reactor was set at 450°C. 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. ) _{3 ·} 6H ₂ O and _4.0g Fe(NO ₃ ) _{3 ·} 9H ₂ O _were dissolved in _200mL deionized water. In 200mL deionized water, this solution is recorded as solution C, wherein the molar ratio of molybdenum to bismuth is 1:1, the molar ratio of cobalt to bismuth is 0.2:1, the molar ratio of lanthanum to bismuth is 0.4:1, and the molar ratio of iron to bismuth is 0.4:1. The molar ratio of bismuth is 0.5:1. In a water bath at 70°C, add B dropwise to C and stir well. Add A dropwise to the above mixed solution, after fully stirring, dropwise add ammonia solution with a mass fraction of 25% in the mixed solution of five kinds of salts, adjust the pH value to 6, 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 140°C for 5 hours, bake in a tube furnace with an oxygen atmosphere at 500°C for 5 hours, grind after cooling, and sieve to obtain 40-60 The purpose is five-component bismuth molybdenum lanthanum catalyst, the catalyst is recorded as BiMoCo _0.2 La _0.4 Fe _0.5 , and it is sealed and stored.

Oxidative Dehydrogenation Process

1.5 mL of the above-mentioned catalyst was filled into a moving bed reactor with an inner diameter of 8 mm, and 1-butene was used as a raw material gas, and its percentage content was 99.9%. At the same time, air was introduced, and the composition was set as 1-butene: air molar ratio was 1:5, and the mixed gas was introduced into the reactor with a space velocity of 40h ^-1 and a catalyst bed temperature of 440°C for reaction. The reaction catalyst is gradually moved to the regeneration reactor, while fresh catalyst is replenished into the moving bed reactor. The space velocity of the regeneration reactor was 20h ^-1 , and the bed temperature of the regeneration reactor was set at 500°C. 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. ) ₃ ·6H ₂ O and _4.8g Fe(NO ₃ ) _{3 ·} 9H ₂ O _were dissolved in _200mL deionized water _. In 200mL deionized water, this solution is recorded as solution C, wherein the molar ratio of molybdenum to bismuth is 1:1, the molar ratio of cobalt to bismuth is 0.4:1, the molar ratio of lanthanum to bismuth is 0.3:1, and the molar ratio of iron to bismuth is 0.3:1. The molar ratio of bismuth is 0.6:1. In a water bath at 60°C, add B dropwise to C and stir well. Add A dropwise to the above mixed solution, after fully stirring, dropwise add ammonia solution with a mass fraction of 25% in the mixed solution of the five salts, adjust the pH value to 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 130°C for 10 hours, bake in a tube furnace with an oxygen atmosphere at 600°C for 6 hours, grind after cooling, and sieve to obtain 40-60 Objective five-component bismuth molybdenum lanthanum catalyst, catalyst is denoted as

BiMoCo _0.4 La _0.3 Fe _0.6 , sealed and stored.

Oxidative Dehydrogenation Process

1.5 mL of the above-mentioned catalyst was filled into a moving bed reactor with an inner diameter of 8 mm, and 1-butene was used as a raw material gas, and its percentage content was 99.9%. At the same time, air was introduced, and the composition was set as 1-butene:air molar ratio was 1:4, and the mixed gas was introduced into the reactor with a space velocity of 30h ^-1 and a catalyst bed temperature of 420°C for reaction. The reaction catalyst is gradually moved to the regeneration reactor, while fresh catalyst is replenished into the moving bed reactor. The space velocity of the regeneration reactor was 25h ^-1 , and the bed temperature of the regeneration reactor was set at 520°C. 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. ) _{3 ·} 6H ₂ O and _3.2g Fe(NO ₃ ) _{3 ·} 9H ₂ O _were dissolved in _200mL deionized water. In 200mL deionized water, this solution is recorded as solution C, wherein the molar ratio of molybdenum to bismuth is 1:1, the molar ratio of cobalt to bismuth is 0.5:1, the molar ratio of lanthanum to bismuth is 0.3:1, and the molar ratio of iron to bismuth is 0.3:1. The molar ratio of bismuth is 0.4:1. In a water bath at 80°C, add B dropwise to C and stir well. Add A dropwise to the above mixed solution, after fully stirring, dropwise add ammonia solution with a mass fraction of 25% in the mixed solution of five kinds of salts, adjust the pH value to 7, after the dropwise addition, continue to Stir in a water bath at 80°C until viscous, transfer the viscous material to a drying oven at 100°C for 12 hours, bake in a tube furnace with an oxygen atmosphere at 600°C for 6 hours, grind after cooling, and sieve to obtain 40-60 Objective five-component bismuth molybdenum lanthanum catalyst, catalyst is denoted as

BiMoCo _0.5 La _0.3 Fe _0.4 , sealed and stored.

Oxidative Dehydrogenation Process

1.5 mL of the above-mentioned catalyst was filled into a moving bed reactor with an inner diameter of 8 mm, and 1-butene was used as a raw material gas, and its percentage content was 99.9%. At the same time, air was introduced, and the composition was set as 1-butene: air molar ratio was 1:6, and the mixed gas was introduced into the reactor with a space velocity of 15h ^-1 and a catalyst bed temperature of 400°C for reaction. The reaction catalyst is gradually moved to the regeneration reactor, while fresh catalyst is replenished into the moving bed reactor. The space velocity of the regeneration reactor was 15h ^-1 , and the bed temperature of the regeneration reactor was set at 480°C. 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. ) _{3 ·} 6H ₂ O and _5.7g Fe(NO ₃ ) _{3 ·} 9H ₂ O were dissolved in _200mL deionized water _. In 200mL deionized water, this solution is recorded as solution C, wherein the molar ratio of molybdenum to bismuth is 1:1, the molar ratio of cobalt to bismuth is 0.3:1, the molar ratio of lanthanum to bismuth is 0.5:1, and the molar ratio of iron to bismuth is 0.5:1. The molar ratio of bismuth is 0.7:1. In a water bath at 50°C, add B dropwise to C and stir well. Add A dropwise to the above mixed solution, after fully stirring, dropwise add ammonia solution with a mass fraction of 25% in the mixed solution of five kinds of salts, adjust the pH value to 7, after the dropwise addition, continue to Stir in a water bath at 50°C until viscous, transfer the viscous material to a drying oven at 120°C for 9 hours, bake in a tube furnace with an oxygen atmosphere at 500°C for 6 hours, grind after cooling, and sieve to obtain 40-60 The purpose is five-component bismuth molybdenum lanthanum catalyst, the catalyst is recorded as BiMoCo _0.3 La _0.5 Fe _0.7 , and it is sealed and stored.

Oxidative Dehydrogenation Process

1.5 mL of the above-mentioned catalyst was filled into a moving bed reactor with an inner diameter of 8 mm, and 1-butene was used as a raw material gas, and its percentage content was 99.9%. At the same time, air was introduced, and the composition was set as 1-butene:air molar ratio was 1:4, and the mixed gas was introduced into the reactor with a space velocity of 10h ^-1 and a catalyst bed temperature of 450°C for reaction. The reaction catalyst is gradually moved to the regeneration reactor, while fresh catalyst is replenished into the moving bed reactor. The space velocity of the regeneration reactor was 10h ^-1 , and the bed temperature of the regeneration reactor was set at 550°C. Gas chromatography analysis 2h, the product reaction result after 10h is as follows:

Claims (3)

1. the method for synthesizing 1,3-butadiene with five component composite oxide catalysts moving beds of Bi/Mo/Co/La/Fe, its feature It is the five component composite oxide catalysts for preparing to be placed in moving-burden bed reactor, and gaseous mixture is imported into reactor In, keeping certain air speed and reaction bed temperature to be reacted, obtain 1,3-butadiene product, catalysts are gradually moved To regeneration reactor, while to fresh makeup catalyst in moving-burden bed reactor；The gaseous mixture includes 1-butylene and air, its Volume ratio is 1:3～6；Certain air speed is 10～50h^-1；The reaction bed temperature is set as 380～450 DEG C；It is described The air speed of regeneration reactor is 10～30h^-1, its bed temperature is set as 450～550 DEG C；

The five components composite oxide catalysts composition includes Bi, Mo, Co, La and Fe, wherein：Molybdenum is 1 with the mol ratio of bismuth： 1, cobalt is 0.01～2 with the mol ratio of bismuth：1, lanthanum is 0.01～1 with the mol ratio of bismuth：1, the mol ratio of ferrum and bismuth is 0.05～ 1：1；In the catalyst：Bismuth from bismuth nitrate, molybdenum from ammonium molybdate, cobalt from cobalt nitrate, lanthanum from Lanthanum (III) nitrate, Ferrum derives from ferric nitrate；

The synthesis of the five components composite oxide catalysts comprises the steps：

(1) according to above-mentioned catalytic component proportioning, the cobalt salt of certain mass, lanthanum salt and iron salt are dissolved in deionized water be made into it is mixed Saline solution is closed, molybdenum salt is dissolved in deionized water into molybdenum saline solution, during bismuth salt is dissolved in containing certain density salpeter solution, by salt-mixture Solution is dropwise added drop-wise in the solution containing molybdenum salt, and is sufficiently stirred for；Again bismuth salt is dropwise added drop-wise in above-mentioned mixed solution；

(2) above-mentioned solution is placed in 50～80 DEG C of water-bath, with the ammonia that mass fraction is 25% dropwise Deca, adjust pH to 3～7；

(3) solution stirring of step (2) is dried to after sticky, being transferred in baking oven, gained solid is fired, after cooling, Jing Grinding, screening obtain 40～60 purpose, five component composite oxide catalysts.

2. 1,3- fourths are synthesized with five component composite oxide catalysts moving beds of Bi/Mo/Co/La/Fe as claimed in claim 1 The method of diene, it is characterised in that in the catalyst：Cobalt is 0.1～0.6 with the mol ratio of bismuth：1, the mol ratio of lanthanum and bismuth For 0.2～0.5：1, ferrum is 0.3～0.8 with the mol ratio of bismuth：1.

3. 1,3- fourths are synthesized with five component composite oxide catalysts moving beds of Bi/Mo/Co/La/Fe as claimed in claim 1 The method of diene, it is characterised in that in the synthesis step (3) of the catalyst：Baking temperature is 80～150 DEG C, drying time For 10～15h；Sintering temperature is 400～700 DEG C, and roasting time is 2～6h.