Alkene co-cracking catalyst and alkene mixed catalytic cracking method

Abstract

The invention provides an alkene co-cracking catalyst and an alkene mixed catalytic cracking method. The catalyst disclosed by the invention is obtained by carrying out hydrothermal aging treatment on20-50 wt% of a modified molecular sieve, 1-50 wt% of a matrix, 3-35 wt% of a binder and 3-15 wt% of a composite additive at the temperature of 500-800 DEG C, the modified molecular sieve is obtainedby sequentially performing alkali treatment, impregnation modification of at least two non-metallic elements, hydro-thermal treatment and impregnation modification of at least three metallic elementson a molecular sieve; and the composite additive at least comprises inorganic acid and cellulose. The alkene co-cracking catalyst provided by the invention has different types of acid centers such assuper acid, strong acid and weak acid, so that an alkene mixed raw material can be catalytically cracked, a relatively high conversion rate can be achieved and can reach 50% or above, the propylene yield is not lower than 20%, the coking amount is lower than 3%, and the catalyst loss within 4 hours is lower than 0.5%.

Description

technical field

[0001] The invention relates to petrochemical technology, in particular to an alkene co-cracking catalyst and a catalytic cracking method for alkene mixed feed. Background technique

[0002] Propylene is an important petrochemical basic raw material, mainly used in the production of polypropylene, acrylonitrile, isopropanol, acetone and propylene oxide, etc. Other uses include alkylation oil, catalytic lamination and dimerization, high octane Alkane gasoline blending materials, etc. In recent years, driven by the rapid growth in demand for downstream derivatives, global propylene consumption has increased significantly. At this stage, propylene is mainly derived from the by-products of ethylene, gasoline and diesel production processes. However, due to the increasingly saturated gasoline and diesel markets, the production of propylene is also severely restricted, and a stable supply cannot be guaranteed.

[0003] The development of new low-carbon olefins pr...

Examples

Embodiment 1

[0059] (1) Preparation of ZSM-5

[0060] First, tetraethyl orthosilicate, sodium aluminate, tetrapropylammonium hydroxide, ammonia and water are mixed according to 100SiO 2 :1Al 2 o 3 :20TPABr:120NH 3 ·H 2 O:2000H 2 The molar ratio of O was mixed, then crystallized at 80°C for 12h, and then crystallized at 180°C for 48h to obtain ZSM-5 with a grain size of 500-3000nm and a silicon-aluminum molar ratio of 100, then washed and pumped Filter and dry at 120°C for 12 hours, and then calcined at 600°C for 10 hours to obtain molecular sieve raw material ZSM-5.

[0061] (2) Alkali treatment of catalyst carrier

[0062] The above-mentioned molecular sieve raw material ZSM-5 was mixed with 0.4mol / L NaOH solution according to the mass ratio of 1:6, then exchanged at 90°C for 2h, then washed to neutrality, then dried at 120°C for 12h, Calcined at 540°C for 2h.

[0063] Mix ZSM-5 molecular sieves with 1mol / L ammonium nitrate solution at a mass ratio of 1:10, then perform ammonium e...

Embodiment 2

[0079] The catalyst was prepared according to the same process as in Example 1, except that the supported non-metallic elements were different.

[0080] Non-metal element impregnation modification steps are:

[0081] (3) boric acid and (NH 4 ) 2 SO 4 The solution is mixed to form an impregnating solution, and the mass ratio of the impregnating solution to HZSM-5 is 0.5:1, and B and S are impregnated on HZSM-5, so that the loading of B is 0.5wt%, and the loading of S is 0.8wt %. Then it was aged at room temperature for 6 hours, dried at 120° C. for 12 hours, and calcined at 540° C. for 4 hours.

[0082] All the other operations are the same as in Example 1.

[0083] The catalytic effect evaluation experiment of the catalyst is the same as in Example 1, and the results are shown in Table 2.

Embodiment 3

[0085] The catalyst was prepared according to the same process as in Example 1, except that the supported metal elements were different, and the conditions for impregnating and modifying the metal elements were different.

[0086] The specific operation of impregnating and modifying HZSM-5 with metal elements is as follows:

[0087] (5.1) Mo impregnation on hydrothermally treated HZSM-5

[0088] First, ammonium molybdate was dissolved in dilute ammonia solution with pH = 8.5, heated to 90°C to dissolve, and then Mo was impregnated on the hydrothermally aged HZSM-5 at a mass ratio of 0.4:1 at room temperature to obtain The loading amount of Mo is 0.2wt%, and then it is aged at room temperature for 6h, dried at 120°C for 12h, and calcined at 540°C for 4h.

[0089] (5.2) Impregnation of Mn, Ca and La on HZSM-5 loaded with Nb

[0090] MnCl 2 , CaCl 2 and La(NO 3 ) 3 After mixing the citric acid solution and HZSM-5 according to the mass ratio of 0.3:1, impregnating Mn, Ca and...

technical field

[0001] The invention relates to petrochemical technology, in particular to an alkene co-cracking catalyst and a catalytic cracking method for alkene mixed feed. Background technique

[0002] Propylene is an important petrochemical basic raw material, mainly used in the production of polypropylene, acrylonitrile, isopropanol, acetone and propylene oxide, etc. Other uses include alkylation oil, catalytic lamination and dimerization, high octane Alkane gasoline blending materials, etc. In recent years, driven by the rapid growth in demand for downstream derivatives, global propylene consumption has increased significantly. At this stage, propylene is mainly derived from the by-products of ethylene, gasoline and diesel production processes. However, due to the increasingly saturated gasoline and diesel markets, the production of propylene is also severely restricted, and a stable supply cannot be guaranteed.

[0003] The development of new low-carbon olefins pr...

Examples

Embodiment 1

[0059] (1) Preparation of ZSM-5

[0060] First, tetraethyl orthosilicate, sodium aluminate, tetrapropylammonium hydroxide, ammonia and water are mixed according to 100SiO 2 :1Al 2 o 3 :20TPABr:120NH 3 ·H 2 O:2000H 2 The molar ratio of O was mixed, then crystallized at 80°C for 12h, and then crystallized at 180°C for 48h to obtain ZSM-5 with a grain size of 500-3000nm and a silicon-aluminum molar ratio of 100, then washed and pumped Filter and dry at 120°C for 12 hours, and then calcined at 600°C for 10 hours to obtain molecular sieve raw material ZSM-5.

[0061] (2) Alkali treatment of catalyst carrier

[0062] The above-mentioned molecular sieve raw material ZSM-5 was mixed with 0.4mol / L NaOH solution according to the mass ratio of 1:6, then exchanged at 90°C for 2h, then washed to neutrality, then dried at 120°C for 12h, Calcined at 540°C for 2h.

[0063] Mix ZSM-5 molecular sieves with 1mol / L ammonium nitrate solution at a mass ratio of 1:10, then perform ammonium e...

Embodiment 2

[0079] The catalyst was prepared according to the same process as in Example 1, except that the supported non-metallic elements were different.

[0080] Non-metal element impregnation modification steps are:

[0081] (3) boric acid and (NH 4 ) 2 SO 4 The solution is mixed to form an impregnating solution, and the mass ratio of the impregnating solution to HZSM-5 is 0.5:1, and B and S are impregnated on HZSM-5, so that the loading of B is 0.5wt%, and the loading of S is 0.8wt %. Then it was aged at room temperature for 6 hours, dried at 120° C. for 12 hours, and calcined at 540° C. for 4 hours.

[0082] All the other operations are the same as in Example 1.

[0083] The catalytic effect evaluation experiment of the catalyst is the same as in Example 1, and the results are shown in Table 2.

Embodiment 3

[0085] The catalyst was prepared according to the same process as in Example 1, except that the supported metal elements were different, and the conditions for impregnating and modifying the metal elements were different.

[0086] The specific operation of impregnating and modifying HZSM-5 with metal elements is as follows:

[0087] (5.1) Mo impregnation on hydrothermally treated HZSM-5

[0088] First, ammonium molybdate was dissolved in dilute ammonia solution with pH = 8.5, heated to 90°C to dissolve, and then Mo was impregnated on the hydrothermally aged HZSM-5 at a mass ratio of 0.4:1 at room temperature to obtain The loading amount of Mo is 0.2wt%, and then it is aged at room temperature for 6h, dried at 120°C for 12h, and calcined at 540°C for 4h.

[0089] (5.2) Impregnation of Mn, Ca and La on HZSM-5 loaded with Nb

[0090] MnCl 2 , CaCl 2 and La(NO 3 ) 3 After mixing the citric acid solution and HZSM-5 according to the mass ratio of 0.3:1, impregnating Mn, Ca and...

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