Nanocomposite catalyst for ethane oxidative dehydrogenation reaction and preparing method thereof

Abstract

The invention discloses a nanocomposite catalyst for an ethane oxidative dehydrogenation reaction and a preparing method thereof. According to the method, firstly, an M1 purity-phase compound in a vanadium molybdenum niobium tellurium multielement metal oxide system is obtained through hydro-thermal synthesis and hydrogen peroxide purification processing; then, cerium oxide sol with the mass fraction of CeO2 being 5-30% is prepared; two methods, namely the sol-gel method and the physical mixing method are adopted, and the M1 purity-phase compound in the vanadium molybdenum niobium tellurium multielement metal oxide system and a finished product of cerium oxide nanometer complex catalyst are obtained. According to the prepared nanocomposite catalyst, the surface of rod-shaped crystal of the M1 purity-phase compound is evenly provided with a great mount of CeO2 nanometer particles, and the grain diameter of the CeO2 ranges from 2 nm to 30 nm. The nanocomposite catalyst has higher catalytic activity and selectivity in the ethane oxidative dehydrogenation reaction process, and meanwhile the synthesizing cost of the vanadium molybdenum niobium tellurium multielement metal oxide system can be lowered through the introduction of the CeO2.

Description

technical field

[0001] The invention belongs to the technical field of industrial catalysis, and in particular relates to a nanocomposite catalyst which can be used in the process of oxidative dehydrogenation of ethane to produce ethylene and a preparation method thereof. Background technique

[0002] The contradiction between the increasingly severe energy and environmental problems and the increasing demand for ethylene is a major problem in the development of the chemical industry today. Compared with the increasingly depleted petroleum resources, the optimization of ethylene production process and the development of new processes using ethane as raw material have received more and more attention, and the raw materials for ethylene production worldwide have shown a clear trend of light weight.

[0003] The ways to produce ethylene from ethane mainly include steam cracking, catalytic direct dehydrogenation, catalytic oxidative dehydrogenation and catalytic weak oxidative d...

Examples

preparation example Construction

[0027] The preparation method of the nanocomposite catalyst provided by the present invention can be prepared by the following two methods: the sol-gel method and the physical mixing method.

[0028] The specific steps of preparing the ethane oxidation dehydrogenation reaction nanocomposite catalyst by the sol-gel method adopted in the present invention include:

[0029] 1) dissolving cerium nitrate and citric acid with a molar ratio of 1:1 to 1:4 in deionized water, and carrying out a constant temperature oil bath, the temperature of the oil bath is 50 to 80°C, and the oil bath time is 16 to 32 hours, Get CeO 2 Cerium oxide sol with a mass fraction of 5-30%;

[0030] 2) Put the M1 pure-phase compound in the molybdenum vanadium niobium tellurium multi-metal oxide system and the cerium oxide sol obtained in step 1) according to the mass ratio of 1:1 to 1:4 in a water bath at 50 to 70°C Mix evenly for 1 to 3 hours;

[0031] 3) Dry the mixture obtained in step 2), and bake it ...

Embodiment 1

[0044] M1 pure phase compound and CeO in a molybdenum vanadium niobium tellurium multi-metal oxide system 2 Nanocomposite catalyst, CeO in nanocomposite catalyst 2 The mass fraction of nanoparticles is 20wt.%, and its particle size is 20nm. The atomic ratio of molybdenum, vanadium, niobium, and tellurium in the molybdenum, vanadium, niobium, and tellurium multi-metal oxides in the catalyst is 1:0.20:0.30:0.10, and the particles The diameter is 75nm and the particle length is 225nm.

[0045] The M1 pure phase compound and CeO in the above molybdenum vanadium niobium tellurium multi-metal oxide system 2 The nanocomposite catalyst preparation method is as follows:

[0046] Under the condition of water bath at 80°C, mix and dissolve ammonium molybdate, vanadyl sulfate, and telluric acid in deionized water with the atomic ratio of molybdenum, vanadium, and tellurium being 1:0.26:0.25 to obtain solution A, and dissolve ammonium niobium oxalate in deionized water. Solution B is ob...

Embodiment 2

[0052] M1 pure phase compound and CeO in a molybdenum vanadium niobium tellurium multi-metal oxide system 2 Nanocomposite catalyst, CeO in nanocomposite catalyst 2 The mass fraction of nanoparticles is 20wt.%, and its particle size is 5nm. The atomic ratio of molybdenum, vanadium, niobium, and tellurium in the molybdenum, vanadium, niobium, and tellurium multi-metal oxides in the catalyst is 1:0.19:0.28:0.08, and the particles The diameter is 40nm and the particle length is 200nm.

[0053] The M1 pure phase compound and CeO in the above molybdenum vanadium niobium tellurium multi-metal oxide system 2 The nanocomposite catalyst preparation method is as follows:

[0054] Under the condition of water bath at 80°C, mix and dissolve ammonium molybdate, vanadyl sulfate, and telluric acid in deionized water with the atomic ratio of molybdenum, vanadium, and tellurium being 1:0.25:0.23 to obtain solution A, and dissolve ammonium niobium oxalate in deionized water. Solution B is obt...

technical field

[0001] The invention belongs to the technical field of industrial catalysis, and in particular relates to a nanocomposite catalyst which can be used in the process of oxidative dehydrogenation of ethane to produce ethylene and a preparation method thereof. Background technique

[0002] The contradiction between the increasingly severe energy and environmental problems and the increasing demand for ethylene is a major problem in the development of the chemical industry today. Compared with the increasingly depleted petroleum resources, the optimization of ethylene production process and the development of new processes using ethane as raw material have received more and more attention, and the raw materials for ethylene production worldwide have shown a clear trend of light weight.

[0003] The ways to produce ethylene from ethane mainly include steam cracking, catalytic direct dehydrogenation, catalytic oxidative dehydrogenation and catalytic weak oxidative d...

Examples

preparation example Construction

[0027] The preparation method of the nanocomposite catalyst provided by the present invention can be prepared by the following two methods: the sol-gel method and the physical mixing method.

[0028] The specific steps of preparing the ethane oxidation dehydrogenation reaction nanocomposite catalyst by the sol-gel method adopted in the present invention include:

[0029] 1) dissolving cerium nitrate and citric acid with a molar ratio of 1:1 to 1:4 in deionized water, and carrying out a constant temperature oil bath, the temperature of the oil bath is 50 to 80°C, and the oil bath time is 16 to 32 hours, Get CeO 2 Cerium oxide sol with a mass fraction of 5-30%;

[0030] 2) Put the M1 pure-phase compound in the molybdenum vanadium niobium tellurium multi-metal oxide system and the cerium oxide sol obtained in step 1) according to the mass ratio of 1:1 to 1:4 in a water bath at 50 to 70°C Mix evenly for 1 to 3 hours;

[0031] 3) Dry the mixture obtained in step 2), and bake it ...

Embodiment 1

[0044] M1 pure phase compound and CeO in a molybdenum vanadium niobium tellurium multi-metal oxide system 2 Nanocomposite catalyst, CeO in nanocomposite catalyst 2 The mass fraction of nanoparticles is 20wt.%, and its particle size is 20nm. The atomic ratio of molybdenum, vanadium, niobium, and tellurium in the molybdenum, vanadium, niobium, and tellurium multi-metal oxides in the catalyst is 1:0.20:0.30:0.10, and the particles The diameter is 75nm and the particle length is 225nm.

[0045] The M1 pure phase compound and CeO in the above molybdenum vanadium niobium tellurium multi-metal oxide system 2 The nanocomposite catalyst preparation method is as follows:

[0046] Under the condition of water bath at 80°C, mix and dissolve ammonium molybdate, vanadyl sulfate, and telluric acid in deionized water with the atomic ratio of molybdenum, vanadium, and tellurium being 1:0.26:0.25 to obtain solution A, and dissolve ammonium niobium oxalate in deionized water. Solution B is ob...

Embodiment 2

[0052] M1 pure phase compound and CeO in a molybdenum vanadium niobium tellurium multi-metal oxide system 2 Nanocomposite catalyst, CeO in nanocomposite catalyst 2 The mass fraction of nanoparticles is 20wt.%, and its particle size is 5nm. The atomic ratio of molybdenum, vanadium, niobium, and tellurium in the molybdenum, vanadium, niobium, and tellurium multi-metal oxides in the catalyst is 1:0.19:0.28:0.08, and the particles The diameter is 40nm and the particle length is 200nm.

[0053] The M1 pure phase compound and CeO in the above molybdenum vanadium niobium tellurium multi-metal oxide system 2 The nanocomposite catalyst preparation method is as follows:

[0054] Under the condition of water bath at 80°C, mix and dissolve ammonium molybdate, vanadyl sulfate, and telluric acid in deionized water with the atomic ratio of molybdenum, vanadium, and tellurium being 1:0.25:0.23 to obtain solution A, and dissolve ammonium niobium oxalate in deionized water. Solution B is obt...

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