Modified IM-5 molecular sieve and preparation method and application thereof

Abstract

The invention specifically provides a modified IM-5 molecular sieve and a preparation method and application thereof, belonging to the field of modification of molecular sieves. The modified IM-5 molecular sieve has a mesoporous area of 150 m<2> / g or above and a mesoporous volume of 0.5 cm<3> / g or above. The modified IM-5 molecular sieve has a large mesoporous area and a large mesoporous volume, so a reactant can more easily contact with an acid center and a product can be rapidly diffused from active center to places out of a catalyst; thus, side reactions are prevented, and the activity, selectivity and service life of the catalyst are improved; e.g., when the modified IM-5 molecular sieve is applied to an alkylation reaction of benzene and methanol, the catalyst has the advantages of a slow inactivation rate, a high benzene conversion rate and high target product selectivity. The modified IM-5 molecular sieve can be used under a high space velocity condition, has high catalysis efficiency, is reactable at a low temperature, shows good activity stability, reduces energy consumption of alkylation, prolongs the service life of the catalyst and is suitable for industrial application.

Description

technical field

[0001] The invention relates to a modified IM-5 molecular sieve, a preparation method of the modified IM-5 molecular sieve, and an application of the modified IM-5 molecular sieve in an alkylation reaction. Background technique

[0002] In recent years, the synthesis of new molecular sieves using diquaternary ammonium salts as templates has attracted more and more attention. Compared with rigid small molecule templates, diquaternary ammonium salts have unique advantages in the synthesis of molecular sieves with new structures or specific structures due to their higher skeleton charge density and rich deformable properties.

[0003] IM-5 molecular sieves were first synthesized by Suk Bong Hong et al. (USP6136290) using pyrrolidine bisquaternary ammonium salt templates. Pore, its pore structure is similar to ZSM-5 molecular sieve, and this molecular sieve also has a 12-membered ring cage structure, which is different from ZSM-5. That The amount of acid and ...

Examples

Embodiment approach

[0024] According to a preferred embodiment of the present invention, preferably the mesoporous area of ​​the modified IM-5 molecular sieve is 151-250m 2 / g, the mesopore volume is 0.55-0.75cm 3 / g.

[0025] According to the present invention, preferably the total specific surface area of ​​the modified IM-5 molecular sieve is 350-500m 2 / g, the micropore area is 200-210m 2 / g, the micropore volume is 0.09-0.12cm 3 / g, the total pore volume is 0.65-0.85cm 3 / g.

[0026] As long as the molecular sieve of the present invention meets the foregoing requirements, the purpose of the present invention can be achieved, and there is no special requirement for its preparation method. For the present invention, the preferred molecular sieve is prepared as follows:

[0027] Under airtight conditions, contact the modifier solution with H-IM-5 molecular sieve, filter, wash, dry, and roast to obtain the modified IM-5 molecular sieve, wherein the modifier solution contains cation, and th...

Embodiment 1

[0067] Prepare IM-5 modified molecular sieve by the method for comparative example 1, difference is that in step (2) with MPPBr 2 (1,5-bis(N-methylpyrrolidine) pentane bromide) and NaOH are formulated into a mixed aqueous solution at a molar ratio of 0.2:1 to replace the NaOH solution. In the mixed solution [OH -1 ] the molar concentration is 0.2mol / L, the reaction time is 2 hours, all the other conditions are the same, and the modified IM-5 molecular sieve Z 2 , the physical and chemical parameters are shown in Table 1.

Embodiment 2

[0069] Prepare the IM-5 modified molecular sieve according to the method of comparative example 1, the difference is, use MPPBr in step (2) 2 (1,5-bis(N-methylpyrrolidine) pentane bromide) and NaOH are formulated into a mixed aqueous solution at a molar ratio of 0.3:1 to replace the NaOH solution, and [OH -1 ] the molar concentration is 0.2mol / L, the reaction time is 2 hours, all the other conditions are the same, and the modified IM-5 molecular sieve Z 3 , the physical and chemical parameters are shown in Table 1.

technical field

[0001] The invention relates to a modified IM-5 molecular sieve, a preparation method of the modified IM-5 molecular sieve, and an application of the modified IM-5 molecular sieve in an alkylation reaction. Background technique

[0002] In recent years, the synthesis of new molecular sieves using diquaternary ammonium salts as templates has attracted more and more attention. Compared with rigid small molecule templates, diquaternary ammonium salts have unique advantages in the synthesis of molecular sieves with new structures or specific structures due to their higher skeleton charge density and rich deformable properties.

[0003] IM-5 molecular sieves were first synthesized by Suk Bong Hong et al. (USP6136290) using pyrrolidine bisquaternary ammonium salt templates. Pore, its pore structure is similar to ZSM-5 molecular sieve, and this molecular sieve also has a 12-membered ring cage structure, which is different from ZSM-5. That The amount of acid and ...

Examples

Embodiment approach

[0024] According to a preferred embodiment of the present invention, preferably the mesoporous area of ​​the modified IM-5 molecular sieve is 151-250m 2 / g, the mesopore volume is 0.55-0.75cm 3 / g.

[0025] According to the present invention, preferably the total specific surface area of ​​the modified IM-5 molecular sieve is 350-500m 2 / g, the micropore area is 200-210m 2 / g, the micropore volume is 0.09-0.12cm 3 / g, the total pore volume is 0.65-0.85cm 3 / g.

[0026] As long as the molecular sieve of the present invention meets the foregoing requirements, the purpose of the present invention can be achieved, and there is no special requirement for its preparation method. For the present invention, the preferred molecular sieve is prepared as follows:

[0027] Under airtight conditions, contact the modifier solution with H-IM-5 molecular sieve, filter, wash, dry, and roast to obtain the modified IM-5 molecular sieve, wherein the modifier solution contains cation, and th...

Embodiment 1

[0067] Prepare IM-5 modified molecular sieve by the method for comparative example 1, difference is that in step (2) with MPPBr 2 (1,5-bis(N-methylpyrrolidine) pentane bromide) and NaOH are formulated into a mixed aqueous solution at a molar ratio of 0.2:1 to replace the NaOH solution. In the mixed solution [OH -1 ] the molar concentration is 0.2mol / L, the reaction time is 2 hours, all the other conditions are the same, and the modified IM-5 molecular sieve Z 2 , the physical and chemical parameters are shown in Table 1.

Embodiment 2

[0069] Prepare the IM-5 modified molecular sieve according to the method of comparative example 1, the difference is, use MPPBr in step (2) 2 (1,5-bis(N-methylpyrrolidine) pentane bromide) and NaOH are formulated into a mixed aqueous solution at a molar ratio of 0.3:1 to replace the NaOH solution, and [OH -1 ] the molar concentration is 0.2mol / L, the reaction time is 2 hours, all the other conditions are the same, and the modified IM-5 molecular sieve Z 3 , the physical and chemical parameters are shown in Table 1.

Images