Efficient sulfur transfer agent for catalytic cracking as well as preparation method and application of efficient sulfur transfer agent

Abstract

The invention relates to the field of petrochemical engineering catalytic materials, in particular to an efficient sulfur transfer agent for catalytic cracking and a preparation method and application thereof.The active component of the sulfur transfer agent is AMnO3, A in the AMnO3 is one or more of Ca and Sr. The sulfur transfer agent is prepared through the following steps that firstly, MnO2 and alkaline earth metal carbonate ACO3 powder are mixed according to the stoichiometric ratio; 2, fully and uniformly grinding the mixed powder; 3, the ground mixture is calcined, and AMnO3 is obtained; the main component of the sulfur transfer agent is manganese-based perovskite which is CaCO3 and / or SrCO3, and the sulfur transfer agent has very strong CO toxicity resistance within the range of 400-700 DEG C, can maintain relatively high desulfurization efficiency, and is suitable for catalytic cracking regeneration flue gas treatment of CO-containing high-temperature flue gas.

Description

Technical Field

[0001] The invention relates to the field of petrochemical catalytic materials, and in particular to a high-efficiency sulfur transfer agent for catalytic cracking, a preparation method and application thereof. Background Art

[0002] In the FCC process, sulfur in the feedstock is converted into SO 2 and SO 3 , and the regeneration flue gas discharge causes environmental pollution. Traditional sulfur transfer agents (such as cerium oxide, zinc oxide-based materials) have problems such as low sulfur capacity, high temperature deactivation, and easy to be poisoned by CO. Existing perovskite-type sulfur transfer agents (such as LaCoO 3 ) has certain activity, but the preparation process is complicated and the cost is high. In addition, the sulfur transfer agent needs to maintain structural stability in the high-temperature reduction-oxidation cycle, while traditional materials are easily reduced and inactivated in flue gas containing CO. Therefore, there is an urgent need to develop a sulfur transfer agent with high sulfur capacity, anti-poisoning and wide temperature range stability. Summary of the invention

[0003] The problem solved by the invention is: in order to solve the unreasonable arrangement of cathodes and anodes in the prior art, a multi-tube electro-coagulation dust removal device with reasonable arrangement of cathodes and anodes, high dust removal efficiency and low system resistance is provided.

[0004] The present invention is implemented through the following technical scheme. The present invention provides a manganese-based perovskite sulfur transfer agent to solve the problems of low sulfur transfer efficiency, poor CO resistance and insufficient high temperature stability in the prior art.

[0005] A highly efficient sulfur transfer agent for catalytic cracking, the active component of which is AMnO 3 , where AMnO 3 A in the above formula is any one or more of Ca and Sr.

[0006] Another aspect of the present invention provides a method for preparing a high-efficiency sulfur transfer agent for catalytic cracking, comprising the following steps:

[0007] 1. MnO 2 Mix with ACO3 powder in a stoichiometric ratio;

[0008] 2. Grind the mixed powder evenly;

[0009] 3. calcining the ground mixture to obtain AMnO3;

[0010] A in ACO3 and AMnO3 is any one or more of MCa and Sr.

[0011] Furthermore, the calcination temperature is 1200-1350°C.

[0012] Furthermore, the calcination time is 15-25h.

[0013] Furthermore, MnO 2 Prepared by hot water method.

[0014] Furthermore, the hot water method comprises: adding Mn(NO3) 2 The solution was sealed in a stainless steel autoclave and heated for a period of time to obtain MnO 2 powder.

[0015] Further, the MnO obtained after heating 2 The powder was washed with water at room temperature and then dried at 30°C-50°C.

[0016] Another aspect of the present invention is an application of a highly efficient sulfur transfer agent for catalytic cracking, comprising: 3 The sulfur transfer agent is used for desulfurization in flue gas environment at 400-700℃.

[0017] The beneficial effects of the present invention are:

[0018] The sulfur transfer agent of the present invention is mainly composed of manganese-based perovskite, which is CaCO 3 and / or SrCO 3 In the range of 400℃-700℃, it has strong CO resistance and can maintain a high desulfurization efficiency. It is suitable for catalytic cracking regeneration flue gas treatment of high-temperature flue gas containing CO. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic diagram of a fixed bed reactor in Example 1;

[0020] Figure 2 In Example 1, SO 2 -N 2 -CO 2 -O 2 -CO as gas flow CaMnO 3 Desulfurization performance curve at 400-800℃;

[0021] Figure 3 For Example 2 SO 2 -N 2 -CO 2 -O 2 -CO as gas flow SrMnO 3 Desulfurization performance curve at 400-700℃. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] Example 1: First, manganese oxide was prepared by hydrothermal method. Mn(NO 3 ) 2 The solution was sealed in a stainless steel autoclave and heated at 180°C for 72 h. The obtained powder was washed with water at room temperature for 2 h and then dried at 40°C for 5 h. 3 After grinding in an aluminum crucible with a molar ratio of 1:1, the mixture was calcined in a muffle furnace at 1200-1350°C for 15-25h. In this embodiment, calcination at 1300°C for 20h was used to obtain CaMnO 3 Sulfur transfer agent granules.

[0024] Experimental process:

[0025] The desulfurization reaction is carried out in a fixed bed reactor, such as Figure 1 As shown, the gas flow rate is controlled by a mass flow meter, nitrogen (N 2 , 5N), sulfur dioxide (SO 2 / N 2 , 200 ppm), oxygen (O 2 , 5N), carbon dioxide (CO / N 2 , 5000ppm) are mixed evenly and enter the temperature-controlled reactor for desulfurization reaction. The outlet gas is detected by gas chromatography (Agilent 8890) and flame photometry (FPD-GC) of ionization (FID-GC) detector. The total gas flow rate for each reaction is maintained at 50mL / min. SO 2 The concentration of SO2 is adjusted by adjusting the flow rate of each gas through the reactor. 2 and CO were controlled at 100 and 1000 ppm, respectively. For each reaction, 50 mg of manganese species (CaMnO 3 130.14 mg) was placed in a 4 mm quartz tube. The reaction temperature was controlled by a cooling bath and a heating furnace. Figure 2 Shows SO 2 -N 2 -CO 2 -O 2 -CO as gas flow CaMnO 3 Desulfurization performance at 400-800℃. The horizontal axis is time and the vertical axis is SO 2The outlet concentration of CaMnO increases with the reaction temperature from 400℃ to 700℃. 3 SO 2 The capture capacity gradually increases. According to the time process, the exit SO 2 The zero emission was maintained at about 37, 80 and 98 minutes respectively.

[0026] Example 2: First, manganese oxide is prepared by a hydrothermal method, and the prepared manganese oxide and SrCO 3 After grinding in an aluminum crucible with a molar ratio of 1:1, the mixture was calcined at 1300 °C for 20 h in a muffle furnace to obtain SrMnO 3 Sulfur transfer agent granules.

[0027] Experimental process:

[0028] The desulfurization reaction is carried out in a fixed bed reactor, such as Figure 1 The gas flow rate is controlled by a mass flow meter, nitrogen (N 2 , 5N), sulfur dioxide (SO 2 / N 2 , 200 ppm), oxygen (O 2 , 5N), carbon dioxide (CO / N 2 , 5000ppm) are mixed evenly and enter the temperature-controlled reactor for desulfurization reaction. The outlet gas is detected by gas chromatography (Agilent 8890) and flame photometry (FPD-GC) of ionization (FID-GC) detector. The total gas flow rate for each reaction is maintained at 50mL / min. SO 2 The concentration of SO2 is adjusted by adjusting the flow rate of each gas through the reactor. 2 and CO were controlled at 100 and 1000 ppm, respectively. For each reaction, 50 mg of manganese species (SrMnO 3 173.43 mg) was placed in a 4 mm quartz tube. The reaction temperature was controlled by a cooling bath and a heating furnace. Figure 3 Shows SO 2 -N 2 -CO 2 -O 2 -CO as gas flow SrMnO 3 Desulfurization performance at 400-700℃. The horizontal axis is time and the vertical axis is SO 2 Outlet concentration, SrMnO 3 It is also highly resistant to CO toxicity during the desulfurization reaction.

[0029] Example 3: First, manganese oxide is prepared by a hydrothermal method, and the prepared manganese oxide and CaCO 3 and SrCO 3After grinding in an aluminum crucible with a molar ratio of 1:0.5:0.5, the mixture was calcined in a muffle furnace at 1300 °C for 20 h to obtain CaMnO 3 and SrMnO 3 Sulfur transfer agent granules.

[0030] In summary, the high-efficiency sulfur transfer agent for catalytic cracking described in the present invention can achieve a synergistic improvement in sulfur transfer efficiency and CO resistance, and provides an efficient solution for the green transformation of catalytic cracking units.

[0031] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the above implementation is only to illustrate the technical concept and features of the present invention, and its purpose is to enable people familiar with this technology to understand the content of the present invention and implement it, and it cannot be used to limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A highly efficient sulfur transfer agent for catalytic cracking, characterized in that: The active component is AMnO3, wherein A in AMnO3 is one or more of Ca and Sr.

2. The method for preparing a high-efficiency sulfur transfer agent for catalytic cracking according to claim 1, characterized in that: The following steps are involved:

1. Mix MnO2 and alkaline earth metal carbonate ACO3 powders in a stoichiometric ratio; 2. Grind the mixed powder evenly; 3. calcining the ground mixture to obtain AMnO3; A in ACO3 and AMnO3 is any one or more of Ca and Sr.

3. The method for preparing a high-efficiency sulfur transfer agent for catalytic cracking according to claim 2, characterized in that: The molar ratio of MnO2 and ACO3 is 1:

1.

4. The method for preparing a high-efficiency sulfur transfer agent for catalytic cracking according to claim 2, characterized in that: The calcination temperature is 1200-1350°C.

5. The method for preparing a high-efficiency sulfur transfer agent for catalytic cracking according to claim 2, characterized in that: The calcination time is 15-25h.

6. The method for preparing a high-efficiency sulfur transfer agent for catalytic cracking according to claim 2, characterized in that: in, MnO2 was prepared by hot water method.

7. The method for preparing a high-efficiency sulfur transfer agent for catalytic cracking according to claim 6, characterized in that: The hot water method comprises: sealing the Mn(NO3)2 solution in a stainless steel autoclave, heating for a period of time to obtain MnO2 powder, washing the MnO2 powder obtained after heating at room temperature, and then drying at 30°C-50°C.

8. The use of a high-efficiency sulfur transfer agent for catalytic cracking according to claim 1, characterized in that: The sulfur transfer agent containing AMnO3 is used for desulfurization in a flue gas environment of 400-700℃.

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