CN1036320C - A cracking catalyst for preparing isobutylene and isopentene - Google Patents

Abstract

A cracking catalyst that can produce isobutylene and isopentene, its components and content are: (1) HZSM55-25m% with a silicon-aluminum ratio of 20-100; (2) a high-silicon-aluminum ratio of 250-450 Silicon HZSM1-5m%; (3) USY zeolite 5-20m%; (4) Beta zeolite 1-5m%; (5) natural clay 30-60m%; (6) inorganic oxide 15-30m%. The preparation method is as follows: adding the homogeneous molecular sieve slurry to the carrier slurry for beating, filtering, drying and molding to obtain a catalyst product. The catalyst has the characteristics of producing more isobutene and isopentene, and can also co-produce high-octane gasoline.

Description

A cracking catalyst for preparing isobutylene and isopentene

The present invention relates to a cracking catalyst, in particular to a cracking catalyst which can produce more isobutene and isopentene.

In recent years, with the development of the automobile industry and the increasing attention to environmental pollution, the United States has successively proposed restrictions on lead and promulgated clean air regulations. Since automobile exhaust emissions contain benzene and other aromatic hydrocarbons and harmful substances that are harmful to human health, in order to reduce the content of harmful substances in automobile emissions and make them meet the emission standards, automobile manufacturers are required to strive to improve the technology for controlling emissions. At the same time, It also requires petrochemical complexes and major companies to produce gasoline with new formulations. At present, countries such as Europe and the United States use the method of adding ethers such as MTBE and TAME to gasoline to reduce the content of pollutants in automobile emissions. Therefore, the demand for isobutylene and isopentene, which are the raw materials of MTBE and TAME ethers, will also increase day by day. In petrochemical complexes, the catalytic cracking process is not only an important means to provide light oil products, but also to provide olefins A processing method of basic organic chemical raw materials. According to the report of US Patent No. 3758403, adding ZSM-5 to the Y-type molecular sieve catalyst can increase the octane number of gasoline and also increase the yield of C ₃ -C ₅ olefins, but the increase is not large. CN1043520A discloses a cracking catalyst for the production of light olefins, mainly used for the production of propylene and butene. The catalyst contains 75-100m% of ZSM-5 and 0-25m% of Y-type zeolite.

CN1069513A discloses a heavy oil catalytic cracking catalyst and its preparation method. The catalyst is composed of Y-type molecular sieve, ZSM-5 molecular sieve and carrier, and is suitable for heavy oil catalytic cracking of atmospheric residue or blending vacuum residue, with high The selectivity of gas olefins can increase the octane number of gasoline and increase the yield of liquefied gas.

US Patent No. 4911823 discloses a method for zeolite beta catalytic cracking of heavy paraffin oil with a wax content of at least 20m%. By this method, high-octane gasoline can be obtained, and the production of iC ₄ ⁼ can also be increased.

According to NPRA AM-91-34 and AM-92-43 reports, Grace Company uses K value of 11.5, distillation range of 215-556 ° C high nitrogen feedstock oil refineries in the West Coast of the United States, on the FCC unit, at 521 ° C 1. When RFG catalyst is used for catalytic cracking reaction, the yields of iC ₄ ^＝ and iC ₅ ^＝ relative to raw materials are respectively 3.8-4.0m% and 4.7-5.1m%. This document also reports that RFG is a newly developed carrier The chemical composition of the non-faujasite-containing catalyst is as follows: the content of Al ₂ O ₃ is 25-35m%, and the content of Na ₂ O is 0.15-0.37m%.

NPRA AM92-45 reported that Engelhard Company used Midland gas oil in the United States as a raw material. On the FCC unit, using ISOplus-2000 catalyst, the yields of iC ₄ ^＝ and iC ₅ ^＝ relative to the raw material were 3.3m% and 4.5m%, respectively. The sum of those is 7.8m%, but this document does not report the composition and content of the ISOplus-2000 catalyst.

The object of the present invention is to prepare a cracking catalyst capable of producing more isobutene and isopentene.

The catalyst mentioned in the present invention is a composite catalyst composed of four active components and a carrier. Its active components are composed of two kinds of HZSM5, USY and beta zeolite with different silicon-aluminum ratios. The carrier is composed of natural clay and organic oxide. The composition of the catalyst is as follows

(1) HZSM5 with a silicon-aluminum ratio of 20-100: 5-25m%;

(2) High-silicon HZSM-5 with a silicon-aluminum ratio of 250-450: 1-5m%;

(3) USY zeolite: 5-20m%;

(4) Beta zeolite: 1-5m%;

(5) Natural clay: 30-60m%;

(6) Inorganic oxides: 15-30m%.

The said HZSM-5 of the present invention can be synthesized by a method without amine, and can also be synthesized by a method with amine.

The said natural clay in the present invention is halloysite.

The inorganic oxide mentioned in the present invention is aluminum oxide, silicon oxide, amorphous silicon aluminum or a mixture thereof.

The precursor of alumina mentioned in the present invention is pseudo-boehmite.

The preparation method of the catalyst of the present invention is: adding the homogeneous molecular sieve slurry to the carrier slurry, beating, filtering, drying, and molding to obtain a catalyst product. The preparation steps are:

(1) Mix and beat natural clay and deionized water for 0.5-1 hour, then add industrial hydrochloric acid to acidify and stir evenly, then add pseudo-boehmite and stir, heat up to 55-60°C, and age for 0.5-1 hour to obtain solid A carrier slurry with a content of 15-25m%, wherein the addition of hydrochloric acid accounts for 15-30m% of the content of Al ₂ O ₃ in pseudo-boehmite;

(2) Mix HZSM-5, USY and beta zeolite with different silicon-aluminum ratios evenly, then add deionized water to beat and homogenize to obtain a molecular sieve slurry with a solid content of 20-40m%;

(3) adding the homogenized molecular sieve slurry to the carrier slurry, beating, filtering, drying, and molding to obtain a catalyst product.

Compared with the catalyst described in the prior art, the catalyst of the present invention has higher yields of isobutene and isopentene when performing catalytic cracking reaction. For example, on the FCC device, select the feedstock oil with similar characteristic factor K value (K value is about 11.5) and close operating conditions (reaction temperature is about 520 ° C), using the catalyst of the present invention, the isobutene yield is 4.33-4.84m %, the yield of isopentene is 5.07-5.77m%, the sum of the two is 9.40-10.61m%, and the RFG catalyst of Grace Company is used, and the three yields are 3.8-4.0m%, 4.7-5.1m% respectively %, 8.5-9.1m%. It can be seen that, using the catalyst of the present invention, the sum of the two isomeric olefins is 11-17% higher than that using the RFG catalyst of Grace Company.

In addition, when the catalyst of the present invention is used for catalytic cracking reaction, while producing more isobutene and isopentene, gasoline with high octane number can also be co-produced.

The following examples will further illustrate the present invention.

(1) Analytical testing method used in the present invention:

1. Al ₂ O ₃ : X-ray fluorescence spectrometry.

2. Na ₂ O: plasma spectrometry (ICP).

3. Fe ₂ O ₃ : X-ray fluorescence spectrometry.

4. Specific surface: N ₂ adsorption method.

5. Pore volume: N ₂ adsorption method.

6. Carbon residue: electric furnace method.

7. Gasoline octane number: Chromatography.

(2) raw material place of origin and specification used in the example of the present invention:

1. Hydrous kaolin: Suzhou China Clay Company, solid content 82.2m%;

2. Pseudoboehmite: Shandong Aluminum Plant, Al ₂ O ₃ content 32m%;

3. HZSM-5: Zhoucun Catalyst Factory, solid content 99m%;

4. USY zeolite: Zhoucun Catalyst Factory, Na ₂ O<1m%;

5. Beta zeolite: produced by the No. 3 Petroleum Plant

Si-aluminum ratio 26, Na ⁺ <0.5m%;

6. Industrial hydrochloric acid: Beijing Organic Chemical Factory.

Instance 1

Take 31 kg of deionized water, add 5.7 kg of halloysite, stir and beat for 1 hour, then add 0.75 kg of industrial hydrochloric acid to acidify, stir for 0.5 hour, then add 9.3 kg of pseudo-boehmite and stir well, heat up to 55 °C, After aging for 1 hour, the carrier slurry was obtained.

1.72 kg of HZSM-5 zeolite (Na ₂ O<0.1m%) with a silicon-aluminum ratio of 64, 0.3 kg of high-silicon HZSM-5 (Na ⁺ =0.02m%) with a silicon-aluminum ratio of 328, and 1.0 kg of USY zeolite, Mix 0.3 kg of zeolite beta (dry basis) evenly, add 6 kg of deionized water to make a slurry, and obtain a molecular sieve slurry after homogenization, add the homogenized molecular sieve slurry to the carrier slurry, beat, filter, shape, and dry to obtain Catalyst A, its component content is shown in Table 1, and its physical and chemical properties are shown in Table 2.

Instance 2

Take 34 kg of deionized water, add 6.7 kg of halloysite, stir and beat for 1 hour, add 0.5 kg of industrial hydrochloric acid to acidify after stirring, stir for 0.5 hour, then add 6.25 kg of pseudo-boehmite, stir, and heat up to 55 °C , aged for 1 hour to prepare a carrier slurry.

In addition, 1.31 kg of HZSM-5 zeolite with a silicon-aluminum ratio of 64, 0.2 kg of high-silicon HZSM-5 with a silicon-aluminum ratio of 328, 0.5 kg of USY, and 0.2 kg of zeolite beta were mixed evenly, and 6.0 kg of deionized water was added for beating. quality, the homogenized molecular sieve slurry was added to the carrier slurry, beating, filtering, molding, and drying to obtain Catalyst B, whose component content is shown in Table 1, and its physical and chemical properties are shown in Table 2.

Example 3

Take 16 kg of deionized water, add 2.8 kg of halloysite, beat for 1 hour, stir well, add 0.38 kg of industrial hydrochloric acid to acidify, stir well, add 4.7 kg of pseudo-boehmite, stir, and heat up to 55 ° C, aging For 1 hour, a vehicle slurry was prepared.

In addition, mix 0.8 kg of HZSM-5 with a silicon-aluminum ratio of 64HZSM-5, 0.2 kg of HZSM-5 with a silicon-aluminum ratio of 328, 0.7 kg of USY, and 0.1 kg of zeolite beta evenly, add 3.0 kg of deionized water, beat, and homogenize. The qualitative molecular sieve slurry was added to the carrier slurry, beaten, filtered, shaped, and dried to obtain catalyst C. The component contents are shown in Table 1, and the physical and chemical properties are shown in Table 2.

Example 4

Take 17 kg of deionized water, add 3.3 kg of halloysite, stir and beat for 1 hour, add 0.25 kg of industrial hydrochloric acid to acidify, stir well, then add 3.1 kg of pseudo-boehmite, stir, heat up to 55°C, and age for 1 hour. A carrier slurry is prepared.

Mix 0.7 kg of HZSM-5 with a silicon-aluminum ratio of 64, 0.1 kg of HZSM-5 zeolite with a silicon-aluminum ratio of 328, 0.4 kg of USY, and 0.1 kg of zeolite beta evenly, add 3.0 kg of deionized water, beat, homogenize, and The homogenized molecular sieve slurry was added to the carrier slurry, beaten, filtered, shaped, and dried to obtain catalyst D, whose component contents are shown in Table 1.

Example 5

The preparation method is the same as example 1, except that the addition of the HZSM-5 with a silicon-aluminum ratio of 64 is 2.03 kilograms, 0.5 kilograms of HZSM-5 with a silicon-aluminum ratio of 328, 1.5 kilograms of USY zeolite, and 0.3 kilograms of zeolite beta to obtain catalyst E. Its component content is shown in Table 1.

Example 6

Take 16 kg of deionized water, add 2.8 kg of halloysite, beat for 1 hour, then add 0.38 kg of industrial hydrochloric acid to acidify, stir well, add 4.7 kg of pseudo-boehmite, stir, heat up to 55 ° C, and age for 1 hour to prepare Obtain the carrier slurry.

In addition, take 0.8 kg of HZSM-5 with a silicon-aluminum ratio of 64, 50.2 kg of HZSM-5 with a silicon-aluminum ratio of 328, 0.5 kg of USY zeolite, and 0.1 kg of zeolite beta, mix well, add 3.0 kg of deionized water for beating, homogenize, and The homogenized molecular sieve slurry was added to the carrier slurry, beaten, filtered, shaped, and dried to obtain catalyst F, whose component content is shown in Table 1.

Example 7

Preparation method is the same as example 1, and just silicon-aluminum ratio is that the add-on of 64HZSM-5 zeolite is 1.7 kilograms, and silicon-aluminum ratio is 0.5 kilogram of HZSM-5 zeolite of 328, 0.5 kilogram of USY zeolite, 0.2 kilogram of beta zeolite, makes catalyst G, Its component content is shown in Table 1.

Instance 8

Catalysts AE of the present invention were evaluated on a small fixed fluidized bed catalytic cracking unit. Evaluation conditions: 200 grams of catalyst loading for 20-100 microns (mainly 60-80 microns), raw material is naphthenic intermediate wax oil, reaction temperature 520 ° C, weight space velocity 10 hours ^-1 , reaction pressure: normal pressure , agent-to-oil ratio 8.0, high temperature water vapor deactivation treatment before catalyst evaluation. The treatment conditions are: 790° C., normal pressure, 100% steam treatment for 10 hours. See Table 3 for raw oil properties, and Table 4 and Table 5 for evaluation results.

Table 6 lists the yields of isobutene and isopentene of Grace's RFG catalyst on the FCC unit. Table 7 lists the properties of the raw oil used by the company.

As can be seen from Table 3-7, Catalyst A-E of the present invention compares with the RFG catalyst of Grace Company, under the close reaction condition (as characteristic factor K value is all about 11.5, distillation range is close) and approaching reaction condition (as characteristic factor K value is similar with the RFG catalyst of Grace Company The reaction temperature is about 520°C), using the catalyst A-E of the present invention, the yield of isobutylene is 4.33-4.84m%, the yield of isoamylene is 5.07-5.77m%, and the sum of the two is 9.40-10.61m%. The three yields of the company's RFC catalyst are 3.8-4.0m%, 4.7-5.1m%, and 8.5-9.1m%, respectively. It shows that the sum of the two isomeric olefins is 11-17% higher than that of the Grace RFG catalyst using the catalyst A-E of the present invention.

In addition, as can be seen from Table 5, when catalyst A-E of the present invention is used for catalytic cracking reaction, while producing more isobutene and isopentene, gasoline with high octane number can also be co-produced, such as motor octane number (MON ) can reach 81-82, and the research octane number (RON) can reach 93-94.

Table 1 Remarks: 1. *64, 328 refers to the silicon-aluminum ratio of HZSM-5.

2. **Pseudo-boehmite is based on the Al ₂ O ₃ content in it.

Table 2 table 3 project data project data Density, 20°C g/ ^cm3 kinematic viscosity, 80°C mm ² /s freezing point, °C aniline point, °C carbon residue, m% basic nitrogen, ppm refractive index, n _D ²⁰ carbon, m% hydrogen, m% sulfur, m% nitrogen, m% nickel, ppm 0.923014.413580.20.126901.495487.2212.270.190.210.36 Characteristic factor K Distillation range, °C initial boiling point 5% 10% 30% 50% 70% 90% 95% dry point 11.56241297325382411437470480510 Raw oil name Naphthenic middle base straight run wax oil

Table 4

table 5

Table 6 project data project data Density, 15°C g/ ^cm3 API Gravity (15°C) Aniline Point, °C Sulfur, m% Total Nitrogen, m% Base Nitrogen, m% Conrad, m% Ni, ppmV, ppmFe, ppmCu, ppmNa, ppm 0.92222.01701.3900.3700.0870.030.0600.5200 WatsonK value D1160 distillation range (0.1MPa) °C initial boiling point 10% 30% 50% 70% 90% 100% 11.51215316370405436487.8556 Raw oil name High Nitrogen Feedstock for West Coast Refinery

Table 7 project data Distillation range of raw oil, ℃ characteristic factor, K value Catalyst name 215-55611.51RFG FCC device operating conditions: reaction temperature, °C conversion rate, m% 52168 Product yield, m% (relative to raw material) C ₃ ⁼ iC ₄ ⁼ 6.3-7.83.8-4.0 iC ₄ ⁼ /TC ₄ ^=* iC ₅ ⁼ iC ₅ ⁼ /TC ₅ ⁼ 0.404.7-5.10.62 Data Sources NPRAAM-91-34AM-92-43 Note: *TC ₄ ⁼ , TC ₅ ⁼ refer to total C ₄ ⁼ , total C ₅ ⁼ .

Claims (6)

1, a kind of cracking catalyst for preparing iso-butylene and isopentene, it is characterized in that the composite catalyst that this catalyzer is made up of four kinds of active ingredients and carrier, its active ingredient is to be made of the HZSM5 of two kinds of Different Silicon aluminum ratios, USY and β zeolite, carrier is made up of natural clay and inorganic oxide, and the component and the content of this catalyzer are as follows:

(1) silica alumina ratio is the HZSM5:5-25m% of 20-100;

(2) silica alumina ratio is the high silicon HZSM5:1-5m% of 250-450;

(3) USY zeolite: 5-20m%;

(4) β zeolite: 1-5m%;

(5) natural clay: 30-60m%;

(6) inorganic oxide: 15-30m%.

2, according to the said catalyzer of claim 1, it is characterized in that (1), (2) said HZSM-5 can synthesize with non-amine method, also can be with there being the amine method synthetic.

3,, it is characterized in that (5) said natural clay is a halloysite according to the said catalyzer of claim 1.

4,, it is characterized in that said inorganic oxide is aluminum oxide, silicon oxide, amorphous aluminum silicide or its mixture in (6) according to the said catalyzer of claim 1.

5, according to the said catalyzer of claim 4, the precursor that it is characterized in that said aluminum oxide is a pseudo-boehmite.

6,, it is characterized in that this Preparation of catalysts method is according to claim 1,5 said catalyzer:

(1) natural clay is mixed making beating 0.5-1 hour with deionized water, add the technical hydrochloric acid acidifying, stir evenly, add again after pseudo-boehmite stirs, be warming up to 55-60 ℃, aging 0.5-1 hour, make the carrier pulp that solid content is 15-25m%, wherein the add-on of hydrochloric acid accounts for Al in the pseudo-boehmite ₂O ₃The 15-30m% of content;

(2) HZSM-5, USY and the β zeolite with the Different Silicon aluminum ratio mixes, and adds the deionized water making beating, and homogeneous makes the molecular sieve pulp that solid content is 20-40m%;

(3) molecular sieve pulp behind the homogeneous is added in the carrier pulp pulls an oar, filter, drying, moulding makes catalyst prod.