Method for preparing sulfur transfer carrier and sulfur transfer agent

Abstract

The invention relates to a method for preparing a sulfur transfer carrier and a sulfur transfer agent, and the method comprises the following steps: S1, contacting chlorine-containing spray drying tail gas with a first alkaline magnesium source slurry, and carrying out a reaction to obtain a first material; the pH value of the mixed material obtained through contact is 7-12, and the reaction temperature is 70-120 DEG C; s2, mixing the first material, second alkaline magnesium source slurry and acidic alumina colloid to obtain a second material; s3, carrying out spray drying and roasting on the second material; the chlorine-containing spray drying tail gas contains particles containing aluminum oxide and magnesium oxide. According to the method disclosed by the invention, the chlorine-containing spray drying tail gas generated in the preparation process of the sulfur transfer carrier can be efficiently utilized, the aluminum oxide particles and the magnesium oxide particles in the chlorine-containing spray drying tail gas are used as raw materials, the prepared sulfur transfer carrier is used for preparing the sulfur transfer agent, and good desulfurization efficiency and relatively low wear index can be obtained.

Description

Technical Field

[0001] This disclosure relates to the field of sulfur transfer carrier preparation, and more specifically, to a method for preparing sulfur transfer carriers and sulfur transfer agents. Background Technology

[0002] In the preparation of some magnesium and aluminum-containing materials, such as the production processes of catalytic cracking sulfur transfer aids and metal scavengers that use magnesium oxide as an SO2 adsorption carrier, the process involves mixing and spray-drying a slurry of active magnesium oxide and acidified alumina. Fine powder entrained in the tail gas containing acidic components during spray drying accounts for approximately 5-10% of the total tail gas volume. Currently, direct absorption using alkaline wastewater in wet scrubbing systems is problematic because the large amount of sodium oxide impurities affects the performance of the desulfurization carrier. The wastewater is simply discharged into the external drainage system, resulting in resource waste. Furthermore, the particle size of the absorbed fine powder is approximately 5-10 μm (D(V,0.5)) and 15-20 μm (D(V,0.9)), far exceeding the particle size requirements of the raw materials needed for preparation. Direct utilization of this powder would also affect the wear performance of the product. Currently, there is no stable method for utilizing fine powder from magnesium and aluminum-containing materials. Summary of the Invention

[0003] The purpose of this disclosure is to provide a method for preparing a sulfur transfer carrier and a sulfur transfer agent, which uses the chlorine-containing spray drying tail gas generated during the preparation of the sulfur transfer carrier as a raw material to improve resource utilization.

[0004] To achieve the above objectives, the first aspect of this disclosure provides a method for preparing a sulfur transfer support, the method comprising the following steps:

[0005] S1. The chlorine-containing spray drying tail gas is contacted with the first alkaline magnesium source slurry and reacted to obtain the first material;

[0006] The pH value of the mixture obtained by the contact is 7-12, and the reaction temperature is 70-120°C;

[0007] S2. Mix the first material, the second alkaline magnesium source slurry, and the acidic alumina colloid to obtain the second material;

[0008] S3. Spray dry and calcinate the second material;

[0009] The exhaust gas from the chlorine-containing spray drying contains particles containing aluminum oxide and magnesium oxide.

[0010] Optionally, the chlorine-containing spray drying exhaust gas is the spray drying exhaust gas generated during the preparation of the sulfur transfer carrier.

[0011] Optionally, the temperature of the chlorine-containing spray-dried exhaust gas is 140–250°C;

[0012] In the exhaust gas from the chlorine-containing spray drying process, the concentration of chlorine is 200–2000 mg / m³. 3 The total concentration of the magnesium oxide and the aluminum oxide is 500–5000 mg / m³. 3 ;

[0013] The average particle size of the particles is 2–10 μm;

[0014] The content of magnesium oxide is 30-60% by weight and the content of aluminum oxide is 40-70% by weight relative to the total weight of the particles.

[0015] Optionally, in step S1, the total weight of magnesium and aluminum in the chlorine-containing spray drying tail gas, calculated as oxides, is 1:(0.5-20) to the weight of magnesium in the first alkaline magnesium source slurry, preferably 1:(3-15).

[0016] Optionally, in step S1, the pH value of the mixture obtained by contact is 8 to 11;

[0017] Optionally, the reaction temperature is 70–100°C;

[0018] Optionally, the reaction time is 0.5 to 3 hours.

[0019] Optionally, the method for preparing the acidic alumina colloid includes: mixing a dispersion containing boehmite and / or aluminum sol with an acid, wherein the molar ratio of the acid to aluminum is 0.2 to 0.7;

[0020] Optionally, the solid content of the dispersion is 5-20% by weight.

[0021] Optionally, in step S2, the total weight of magnesium and aluminum in the first material, the weight ratio of magnesium in the second alkaline magnesium source slurry to aluminum in the acidic alumina colloid, based on oxides, is 1:(0.5-20):(1-30).

[0022] Optionally, the mixing method is pulping, which is carried out under stirring conditions for 5 to 120 minutes.

[0023] Optionally, in step S3, the conditions for spray drying include: the outlet temperature is 140–250°C;

[0024] The roasting conditions include a temperature of 300–700°C and a time of 0.5–10 h.

[0025] Optionally, the first alkaline magnesium source slurry and the second alkaline magnesium source slurry contain an alkaline magnesium source, which includes magnesium hydroxide and / or magnesium oxide, wherein the magnesium oxide has a citric acid value of 100–200s when tested at 30°C. -1 .

[0026] Optionally, the solid content of the first alkaline magnesium source slurry and the second alkaline magnesium source slurry are 0.3 to 30% by weight, and the pH value is 9 to 12.5, respectively.

[0027] The second aspect of this disclosure provides a method for preparing a sulfur transfer agent, the method comprising: contacting a sulfur transfer carrier prepared by the method of the first aspect of this disclosure with a solution containing an active metal source.

[0028] Optionally, the active metal source includes one or more of the following: cerium source, lanthanide metal source, manganese source, copper source, zirconium source, and iron source;

[0029] Optionally, the contact reaction may be carried out by supersaturated impregnation under the following conditions: a temperature of 10–80°C and a time of 5–90 min.

[0030] Through the above technical solution, this disclosure uses the chlorine-containing spray drying tail gas generated during the preparation of the sulfur transfer carrier as raw material, makes full use of the larger particles containing magnesium oxide and aluminum oxide in it to prepare the sulfur transfer carrier, and uses it as a carrier to prepare the sulfur transfer agent, which has an abrasion index and desulfurization efficiency comparable to the sulfur transfer agents prepared by the prior art.

[0031] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Detailed Implementation

[0032] The following provides a detailed description of specific embodiments of this disclosure. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit this disclosure.

[0033] The first aspect of this disclosure provides a method for preparing a sulfur transfer support, the method comprising the following steps:

[0034] S1. The chlorine-containing spray drying tail gas is contacted with the first alkaline magnesium source slurry and reacted to obtain the first material;

[0035] The pH value of the mixture obtained by the contact is 7-12, and the reaction temperature is 70-120°C;

[0036] S2. Mix the first material, the second alkaline magnesium source slurry, and the acidic alumina colloid to obtain the second material;

[0037] S3. Spray dry and calcinate the second material;

[0038] The exhaust gas from the chlorine-containing spray drying contains particles containing aluminum oxide and magnesium oxide.

[0039] This disclosure uses the tail gas generated during the preparation of the sulfur transfer carrier as raw material, and recycles the larger particles containing magnesium oxide and aluminum oxide, thereby improving the utilization rate of aluminum oxide and magnesium oxide, avoiding resource waste, and reducing the preparation cost of the sulfur transfer carrier. The method of this disclosure can also avoid the problem that direct use of large particle size will affect wear performance. The prepared sulfur transfer carrier has a specific structure, and the sulfur transfer agent prepared with it as a carrier has good desulfurization performance.

[0040] In this disclosure, the chlorine-containing spray drying tail gas is the spray drying tail gas generated during the preparation of the sulfur transfer carrier. Specifically, it can be the tail gas generated by the prior art in the preparation of the sulfur transfer carrier, or the spray drying tail gas generated by the preparation of the sulfur transfer carrier in this disclosure. That is, the tail gas generated by the spray drying in step S3 can be used in step S1. The chlorine-containing spray drying tail gas contains particles containing magnesium oxide and aluminum oxide, as well as chlorine in the form of hydrogen chloride.

[0041] In this disclosure, the first alkaline magnesium source slurry and the second alkaline magnesium source slurry may be the same or different.

[0042] According to one embodiment of this disclosure, the first alkaline magnesium source slurry and the second alkaline magnesium source slurry contain an alkaline magnesium source, which includes magnesium hydroxide and / or magnesium oxide, wherein the magnesium oxide has a citric acid value of 100-200s when tested at 30°C. -1 .

[0043] According to one embodiment of this disclosure, the solid content of the first alkaline magnesium source slurry and the second alkaline magnesium source slurry are 0.3-30% by weight, and the pH value is 9-12.5. Since the tail gas of chlorine spray drying contains hydrogen chloride, the use of alkaline magnesium source can react with hydrogen chloride while providing magnesium element, balance the pH value, and reduce the particle size, so that the prepared sulfur transfer carrier has a specific structure, improve desulfurization efficiency and wear performance.

[0044] In this disclosure, the method for preparing the slurry containing an alkaline magnesium source is conventional in the art, and may include, for example, slurrying the alkaline magnesium source in decationized water.

[0045] In this disclosure, step S1 can be carried out in a reaction vessel, and the air volume of the chlorine-containing spray drying tail gas can be 10,000 to 30,000 mg / m³. 3 .

[0046] Unless otherwise specified, all pH values ​​in this disclosure are measured under normal pressure and at 25°C.

[0047] According to one embodiment of this disclosure, the temperature of the chlorine-containing spray-drying exhaust gas is 140–250°C. The chlorine-containing spray-drying exhaust gas used in this disclosure carries its own heat; using it as a raw material to prepare a sulfur transfer carrier can fully utilize the heat in the exhaust gas, further reducing energy consumption and costs, and improving resource utilization.

[0048] According to one embodiment of this disclosure, the concentration of chlorine in the chlorine-containing spray-dried exhaust gas is 200–2000 mg / m³. 3 The total concentration of the magnesium oxide and the aluminum oxide is 500–5000 mg / m³. 3 .

[0049] According to one embodiment of this disclosure, the average particle size is 2 to 10 μm.

[0050] According to one embodiment of this disclosure, the content of magnesium oxide is 30-60% by weight and the content of aluminum oxide is 40-70% by weight relative to the total weight of the particles.

[0051] In order to further improve the desulfurization performance of the desulfurization catalyst, according to one embodiment of the present disclosure, in step S1, the total weight of magnesium and aluminum elements in the chlorine-containing spray-dried tail gas, calculated as oxides, is 1:(0.5-20), preferably 1:(3-15); wherein, "the total weight of magnesium and aluminum elements in the chlorine-containing spray-dried tail gas" refers to the total weight of magnesium and aluminum elements in the tail gas actually captured.

[0052] In this disclosure, in step S1, the pH value can be controlled by the introduction time of the chlorine-containing spray drying tail gas, or it can be adjusted by adding acid.

[0053] In this disclosure, in step S1, the temperature of the mixture obtained by contact is 20 to 110°C, preferably 70 to 100°C.

[0054] According to one embodiment of this disclosure, in step S1, the reaction temperature is 70–100°C, preferably 80–100°C.

[0055] According to one embodiment of this disclosure, in step S1, the pH value of the mixture obtained through contact is 8 to 11.

[0056] In this disclosure, the reaction in step S1 may not require a temperature control device, and the heat required for the reaction temperature may be provided by the exhaust gas from the chlorine-containing spray drying; alternatively, a temperature control device may be installed to control the temperature of the material to the required reaction temperature.

[0057] According to one embodiment of this disclosure, in step S1, the reaction time is 0.5 to 3 hours.

[0058] According to one embodiment of this disclosure, step S1 further includes: performing solid-liquid separation on the mixture obtained from the reaction to obtain the first material; the solid-liquid separation method is conventional in the art, such as filtration, and this disclosure does not require specific steps and conditions.

[0059] According to one embodiment of this disclosure, the method for preparing acidic alumina colloid is conventional in the art and may include, for example, mixing a dispersion containing boehmite and / or aluminum sol with an acid, wherein the molar ratio of acid to aluminum is 0.2 to 0.7, and the acid used may be, for example, hydrochloric acid. This disclosure does not impose specific limitations on the concentration of the acid; the solid content of the dispersion is 5 to 20% by weight, and the water used in the dispersion may be acidic water with a pH value of, for example, 1 to 4.

[0060] In order to further improve the desulfurization performance of the desulfurization catalyst, according to one embodiment of the present disclosure, in step S2, the total weight of magnesium and aluminum in the first material, the weight ratio of magnesium in the second alkaline magnesium source slurry to aluminum in the acidic alumina colloid, based on oxides, is 1:(0.5-20):(1-30), preferably 1:(1-7):(1-20).

[0061] According to one embodiment of this disclosure, in order to make the mixing more thorough, in step S2, the mixing method is pulping, which is carried out under stirring conditions. The stirring method is conventional in the art, and the time is 5 to 120 minutes.

[0062] In order to make the prepared sulfur transfer agent have better desulfurization performance, according to one embodiment of the present disclosure, in step S3, the spray drying method is conventional in the art, and the conditions include: the outlet temperature is 140-250°C, preferably 140-180°C.

[0063] In order to make the prepared sulfur transfer agent have better desulfurization performance, according to one embodiment of the present disclosure, in step S3, the calcination method is conventional in the art, and the conditions include: temperature of 300-700°C and time of 0.5-10h; preferably, temperature of 500-650°C and time of 1-3h.

[0064] The second aspect of this disclosure provides a method for preparing a sulfur transfer agent, the method comprising: contacting a sulfur transfer carrier prepared by the method of the first aspect of this disclosure with a solution containing an active metal source.

[0065] According to one embodiment of this disclosure, the active metal source includes a soluble active metal salt, such as one or more of cerium source, lanthanide metal source, manganese source, copper source, zirconium source and iron source. Specifically, the active metal source is one or more of the corresponding nitrate and chloride salts; the amount of active metal source used is conventional in the art.

[0066] According to one embodiment of this disclosure, the contact reaction is preferably carried out by supersaturated impregnation, with conditions including a temperature of 10–80°C and a time of 5–90 min. The specific steps of supersaturated impregnation are conventional in the art.

[0067] This disclosure does not impose specific restrictions on the desulfurization method. For example, it can be carried out in a fixed bed or a fluidized bed, which is conventional in the art and is not specifically required here.

[0068] The present invention will be further illustrated by the following examples, but the present invention is not limited thereto.

[0069] In the following examples and comparative examples:

[0070] The method for measuring citric acid value is as follows: Q / SH 361750.

[0071] The preparation method of acidic boehmite acidic colloid is as follows: Boehmite (Shandong Branch of Aluminum Corporation of China Limited) with a solid content of 15% by weight is added to acidic water (pH value of 3.5), and hydrochloric acid is added, with the molar ratio of acid to aluminum element being 0.4;

[0072] Preparation of the first alkaline magnesium source slurry 1: Activated magnesium oxide (30℃, citric acid value 180s) was used... -1 The particle size distribution (D(V, 0.5) was 2.7 μm) was slurried in decationized water, and the pH value was measured to be 10.9 and the solid content was 3% by weight.

[0073] Preparation of the first alkaline magnesium source slurry 2: Activated magnesium oxide (30℃, citric acid value 180s) was used... -1 The particle size distribution (D(V, 0.5) was 2.9 μm) was slurried in decationized water, and the pH value was measured to be 9.6 and the solid content was 0.5% by weight.

[0074] Alkaline wastewater: solid content 3.3% by weight, of which silicon content (SiO2) is 83% by weight, sodium content (Na2O) is 8.9% by weight, aluminum content (Al2O3) is 7.2% by weight, and the measured pH value is 10.3.

[0075] Preparation of the second alkaline magnesium source slurry: Activated magnesium oxide (30℃, citric acid value 180s) -1The sample (D(V, 0.5) was 2.9 μm) was pulped in decationized water with a solid content of 25% by weight.

[0076] Activated magnesium oxide, produced by Beijing Chemical Plant;

[0077] The pore volume of the sulfur transfer agent was determined according to NB / SH / T 0955-2017.

[0078] The apparent bulk density of the sulfur transfer agent was determined according to NB / SH / T 0954-2017.

[0079] The wear index of sulfur transfer agent was determined according to NB / SH / T 0964-2017.

[0080] The concentration of solid components in the exhaust gas from chlorine-containing spray drying was determined according to GB / T 16157-1996.

[0081] After collecting the spray drying exhaust gas and diluting it with nitrogen to the applicable range of HJ 548-2016, the chlorine concentration in the chlorine-containing spray drying exhaust gas was determined.

[0082] The ratio of magnesium oxide to aluminum oxide in the sample was determined by X-ray fluorescence spectroscopy (XRF).

[0083] The test method for the content of each component in the first material: the sample composition was determined by X-ray fluorescence spectroscopy (XRF).

[0084] The average particle size was determined according to NB / SH / T 0951-2017.

[0085] Example 1

[0086] The sulfur transfer agent RS-1 was prepared using the following steps:

[0087] (1) Add 160,000 kg (35°C) of the first alkaline magnesium source slurry to the reactor, and introduce the chlorine-containing spray drying tail gas from the bottom of the reactor (air volume of 25,000 m³ / h). 3 / h, at the reactor inlet: the total concentration of magnesium oxide and aluminum oxide is 1533 mg / m³. 3 The chlorine content is 480 mg / m³. 3 The magnesium oxide content was 50% by weight, the aluminum oxide content was 50% by weight, the temperature was 140℃, the average particle size was 5.6 μm, and the total concentration of magnesium oxide and aluminum oxide at the reactor outlet was 306.7 mg / m³. 3 The Cl element content is 94.9 mg / m³. 3 The mixture was introduced over a period of 4 hours, with a temperature of 95°C and a pH of 10.6. The reaction was continued at this temperature for another 2 hours, followed by filtration to obtain the first material.

[0088] Based on oxides, the total weight ratio of magnesium and aluminum in the chlorine-containing spray drying exhaust gas to the weight ratio of magnesium in the first alkaline magnesium source slurry 1 is 1:14.7.

[0089] (2) Under stirring conditions, the first material, the second alkaline magnesium source slurry and the acidic pseudoboehmite colloid are mixed for 60 minutes to obtain the second material.

[0090] In terms of oxides, in step (2), the total weight of magnesium and aluminum in the first material and the weight ratio of magnesium in the second alkaline magnesium source slurry to aluminum in the acidic pseudoboehmite colloid are 1:2:2.5.

[0091] (3) The second material was spray-dried (exit temperature was 160℃) and calcined (calcination temperature was 600℃, calcination time was 3h) to obtain a sulfur transfer carrier;

[0092] (4) The above sulfur transfer carrier was supersaturated with cerium chloride solution to obtain sulfur transfer agent (the cerium content in the cerium chloride solution, calculated as Ce2O3, was 4wt%, the time was 0.5h, and the temperature was 30℃).

[0093] The parameters of sulfur transfer agent RS-1 are listed in Table 1.

[0094] Example 2

[0095] The sulfur transfer agent RS-2 was prepared using the method of Example 1, except that, in step (2) based on oxides, the total weight of magnesium and aluminum in the first material and the weight ratio of magnesium in the second alkaline magnesium source slurry to aluminum in the acidic pseudoboehmite colloid were 1:1:2.5. The parameters of the sulfur transfer agent are listed in Table 1.

[0096] Example 3

[0097] The sulfur transfer agent RS-3 was prepared using the method of Example 1, except that, in step (2) based on oxides, the total weight of magnesium and aluminum in the first material and the weight ratio of magnesium in the second alkaline magnesium source slurry to aluminum in the acidic pseudoboehmite colloid were 1:15:12. The parameters of the sulfur transfer agent are listed in Table 1.

[0098] Example 4

[0099] The sulfur transfer agent RS-4 was prepared using the following steps:

[0100] (1) Add 160,000 kg (25°C) of the first alkaline magnesium source slurry to the reactor, and introduce the chlorine-containing spray drying tail gas from the bottom of the reactor (air volume of 25,000 m³ / h). 3 / h, at the reactor inlet: the total concentration of magnesium oxide and aluminum oxide is 4513 mg / m³. 3The Cl element content is 770 mg / m³. 3 The magnesium oxide content was 50% by weight, the aluminum oxide content was 50% by weight, the temperature was 140℃, the average particle size was 4.9 μm, and the total concentration of magnesium oxide and aluminum oxide at the reactor outlet was 1092.7 mg / m³. 3 The Cl element content is 179.1 mg / m³. 3 The influent time was 2 hours, the temperature of the mixture was 70°C, and the pH value was 10.5. The reaction was continued at this temperature for another 2 hours, and then filtered to obtain the first material.

[0101] Based on oxides, the total weight ratio of magnesium and aluminum in the chlorine-containing spray drying exhaust gas to the weight ratio of magnesium in the first alkaline magnesium source slurry 1 is 1:10.5.

[0102] (2) Under stirring conditions, the first material, the second alkaline magnesium source slurry and the acidic pseudoboehmite colloid are mixed for 60 minutes to obtain the second material.

[0103] In terms of oxides, in step (2), the total weight of magnesium and aluminum in the first material and the weight ratio of magnesium in the second alkaline magnesium source slurry to aluminum in the acidic pseudoboehmite colloid are 1:2:2.5.

[0104] (3) The second material was spray-dried (exit temperature was 160℃) and calcined (calcination temperature was 600℃, calcination time was 3h) to obtain a sulfur transfer carrier;

[0105] (4) The above sulfur transfer carrier was supersaturated with cerium chloride solution to obtain sulfur transfer agent (the cerium content in the cerium chloride solution, calculated as Ce2O3, was 4wt%, the time was 0.5h, and the temperature was 30℃).

[0106] The parameters of sulfur transfer agent RS-4 are listed in Table 1.

[0107] Example 5

[0108] The sulfur transfer agent RS-5 was prepared using the following steps:

[0109] (1) Add 260,000 kg (35°C) of the first alkaline magnesium source slurry to the reactor, and introduce the chlorine-containing spray drying tail gas from the bottom of the reactor (air volume of 25,000 m³ / h). 3 / h, at the reactor inlet: the total concentration of magnesium oxide and aluminum oxide is 4883 mg / m³. 3 The Cl element content is 890 mg / m³ 3 The magnesium oxide content was 50% by weight, the aluminum oxide content was 50% by weight, the temperature was 140℃, the average particle size was 5.2 μm, and the total concentration of magnesium oxide and aluminum oxide at the reactor outlet was 1269.6 mg / m³.3 The Cl element content is 229.6 mg / m³. 3 The mixture was introduced over a period of 4 hours, with a temperature of 95°C and a pH of 8.2. The reaction was continued at this temperature for another 2 hours, followed by filtration to obtain the first material.

[0110] Based on oxides, the total weight ratio of magnesium and aluminum in the chlorine-containing spray drying exhaust gas to the weight ratio of magnesium in the first alkaline magnesium source slurry 2 is 1:0.83.

[0111] (2) Under stirring conditions, the first material, the second alkaline magnesium source slurry and the acidic pseudoboehmite colloid are mixed for 60 minutes to obtain the second material.

[0112] In terms of oxides, in step (2), the total weight of magnesium and aluminum in the first material and the weight ratio of magnesium in the second alkaline magnesium source slurry to aluminum in the acidic pseudoboehmite colloid are 1:2:2.5.

[0113] (3) The second material was spray-dried (exit temperature was 160℃) and calcined (calcination temperature was 600℃, calcination time was 3h) to obtain a sulfur transfer carrier;

[0114] (4) The above sulfur transfer carrier was supersaturated with cerium chloride solution to obtain sulfur transfer agent (the cerium content in the cerium chloride solution, calculated as Ce2O3, was 4wt%, the time was 0.5h, and the temperature was 30℃).

[0115] The parameters of sulfur transfer agent RS-5 are listed in Table 1.

[0116] Example 6

[0117] The sulfur transfer agent RS-6 was prepared using the following steps:

[0118] (1) Add 260,000 kg (15°C) of the first alkaline magnesium source slurry to the reactor, and introduce the chlorine-containing spray drying tail gas from the bottom of the reactor (air volume of 25,000 m³ / h). 3 / h, at the reactor inlet: the total concentration of magnesium oxide and aluminum oxide is 3511 mg / m³. 3 The chlorine (Cl) content is 1740 mg / m³. 3 The magnesium oxide content was 30 wt%, the aluminum oxide content was 70 wt%, the temperature was 140℃, the average particle size was 4.8 μm, and the concentration of magnesium oxide and aluminum oxide at the reactor outlet was 842.1 mg / m³. 3 The Cl element content is 469.1 mg / m³. 3 The reaction was carried out for 6 hours, the temperature of the mixture was 98℃, the pH value was 7.4, and the reaction was continued for 2 hours at this temperature. After filtration, the first material was obtained.

[0119] Based on oxides, the total weight ratio of magnesium and aluminum in the chlorine-containing spray drying exhaust gas to the weight ratio of magnesium in the first alkaline magnesium source slurry 2 is 1:0.75.

[0120] (2) Under stirring conditions, the first material, the second alkaline magnesium source slurry and the acidic pseudoboehmite colloid are mixed for 60 minutes to obtain the second material.

[0121] In terms of oxides, in step (2), the total weight of magnesium and aluminum in the first material and the weight ratio of magnesium in the second alkaline magnesium source slurry to aluminum in the acidic pseudoboehmite colloid are 1:2:2.5.

[0122] (3) The second material was spray-dried (exit temperature was 160℃) and calcined (calcination temperature was 600℃, calcination time was 3h) to obtain a sulfur transfer carrier;

[0123] (4) The above sulfur transfer carrier was supersaturated with cerium chloride solution to obtain sulfur transfer agent (the cerium content in the cerium chloride solution, calculated as Ce2O3, was 4wt%, the time was 0.5h, and the temperature was 30℃).

[0124] The parameters of sulfur transfer agent RS-6 are listed in Table 1.

[0125] Comparative Example 1

[0126] The sulfur transfer agent DB-1 was prepared using the following steps:

[0127] (1) Under stirring conditions, the second alkaline magnesium source slurry and acidic pseudoboehmite colloid were mixed for 60 min, and then spray-dried (exit temperature of 160℃) and calcined (calcination temperature of 600℃, calcination time of 3 h) to obtain the sulfur transfer carrier.

[0128] Based on oxides, the weight ratio of magnesium in the second alkaline magnesium source slurry to aluminum in the acidic pseudoboehmite colloid is 3:2.5.

[0129] (4) The above sulfur transfer carrier was supersaturated with cerium chloride solution to obtain sulfur transfer agent (the cerium content in the cerium chloride solution, calculated as Ce2O3, was 4wt%, the time was 0.5h, and the temperature was 30℃).

[0130] The parameters of sulfur transfer agent DB-1 are listed in Table 1.

[0131] Comparative Example 2

[0132] The sulfur transfer agent DB-2 was prepared using the following steps:

[0133] (1) Add 60,000 kg (35°C) of alkaline wastewater to the reactor, and introduce chlorine-containing spray drying exhaust gas from the bottom of the reactor (airflow rate of 25,000 m³ / h). 3 / h, at the reactor inlet: the total concentration of magnesium oxide and aluminum oxide is 1492 mg / m³. 3 The Cl element content is 467 mg / m³. 3 The magnesium oxide content was 50% by weight, the aluminum oxide content was 50% by weight, the temperature was 140℃, the average particle size was 5.1 μm, and the concentration of magnesium oxide and aluminum oxide at the reactor outlet was 257.2 mg / m³. 3 The Cl element content is 78.9 mg / m³. 3 The influent time was 4 hours, the temperature of the mixture was 95°C, the pH value was 9.4, and the reaction continued at this temperature for 2 hours. After filtration, the first material was obtained.

[0134] Based on oxides, the ratio of the total weight of magnesium and aluminum in the tail gas of chlorine spray drying to the total weight of silicon and aluminum in alkaline wastewater is 1:14.5.

[0135] (2) Under stirring conditions, the first material, the second alkaline magnesium source slurry and the acidic pseudoboehmite colloid are mixed for 60 minutes to obtain the second material.

[0136] In terms of oxides, in step (2), the total weight of magnesium, aluminum and silicon in the first material, the weight ratio of magnesium in the second alkaline magnesium source slurry to aluminum in the acidic pseudoboehmite colloid is 1:2:2.5.

[0137] (3) The second material was spray-dried (exit temperature was 160℃) and calcined (calcination temperature was 600℃, calcination time was 3h) to obtain a sulfur transfer carrier;

[0138] (4) The above sulfur transfer carrier was supersaturated with cerium chloride solution to obtain sulfur transfer agent (the cerium content in the cerium chloride solution, calculated as Ce2O3, was 4wt%, the time was 0.5h, and the temperature was 30℃).

[0139] The parameters of sulfur transfer agent DB-2 are listed in Table 1.

[0140] Comparative Example 3

[0141] The sulfur transfer agent DB-3 was prepared using the following steps:

[0142] (1) Add 160,000 kg (15°C) of the first alkaline magnesium source slurry to the reactor, and introduce the chlorine-containing spray drying tail gas from the bottom of the reactor (air volume of 25,000 m³ / h). 3 / h, at the reactor inlet: the total concentration of magnesium oxide and aluminum oxide is 1473 mg / m³.3 The Cl element content is 490 mg / m³ 3 The magnesium oxide content was 50% by weight, the aluminum oxide content was 50% by weight, the temperature was 140℃, the average particle size was 5.1 μm, and the total concentration of magnesium oxide and aluminum oxide at the reactor outlet was 238.7 mg / m³. 3 The Cl element content is 79.1 mg / m³. 3 The inlet time is 4 hours. The temperature of the mixture is controlled at 45°C and the pH value is 10.4 by the water-cooling jacket of the reactor. The reaction continues at this temperature for 2 hours. After filtration, the first material is obtained.

[0143] Based on oxides, the total weight ratio of magnesium and aluminum in the chlorine-containing spray drying exhaust gas to the weight ratio of magnesium in the first alkaline magnesium source slurry 1 is 1:14.6.

[0144] (2) Under stirring conditions, the first material, the second alkaline magnesium source slurry and the acidic pseudoboehmite colloid are mixed for 60 minutes to obtain the second material.

[0145] In terms of oxides, in step (2), the total weight of magnesium and aluminum in the first material and the weight ratio of magnesium in the second alkaline magnesium source slurry to aluminum in the acidic pseudoboehmite colloid are 1:2:2.5.

[0146] (3) The second material was spray-dried (exit temperature was 160℃) and calcined (calcination temperature was 600℃, calcination time was 3h) to obtain a sulfur transfer carrier;

[0147] (4) The above sulfur transfer carrier was supersaturated with cerium chloride solution to obtain sulfur transfer agent (the cerium content in the cerium chloride solution, calculated as Ce2O3, was 4wt%, the time was 0.5h, and the temperature was 30℃).

[0148] The parameters of sulfur transfer agent DB-3 are listed in Table 1.

[0149] Comparative Example 4

[0150] The sulfur transfer agent DB-4 was prepared using the following steps:

[0151] (1) Add 160,000 kg (35°C) of the first alkaline magnesium source slurry to the reactor, and introduce the chlorine-containing spray drying tail gas from the bottom of the reactor (air volume of 25,000 m³ / h). 3 / h, at the reactor inlet: the total concentration of magnesium oxide and aluminum oxide is 1561 mg / m³. 3 The Cl element content is 470 mg / m³. 3The magnesium oxide content was 50% by weight, the aluminum oxide content was 50% by weight, the temperature was 140℃, the average particle size was 5.6 μm, and the total concentration of magnesium oxide and aluminum oxide at the reactor outlet was 301.7 mg / m³. 3 The Cl element content is 93.2 mg / m³. 3 The influent time was 4 hours, the temperature of the mixture was 95℃, the pH value was 10.6, hydrochloric acid was added to bring the pH to 6.5, and the reaction continued at this temperature for 2 hours. After filtration, the first material was obtained.

[0152] Based on oxides, the total weight ratio of magnesium and aluminum in the chlorine-containing spray drying exhaust gas to the weight ratio of magnesium in the first alkaline magnesium source slurry 1 is 1:14.3.

[0153] (2) Under stirring conditions, the first material, the second alkaline magnesium source slurry and the acidic pseudoboehmite colloid are mixed for 60 minutes to obtain the second material.

[0154] In terms of oxides, in step (2), the total weight of magnesium and aluminum in the first material and the weight ratio of magnesium in the second alkaline magnesium source slurry to aluminum in the acidic pseudoboehmite colloid are 1:2:2.5.

[0155] (3) The second material was spray-dried (exit temperature was 160℃) and calcined (calcination temperature was 600℃, calcination time was 3h) to obtain a sulfur transfer carrier;

[0156] (4) The above sulfur transfer carrier was supersaturated with cerium chloride solution to obtain sulfur transfer agent (the cerium content in the cerium chloride solution, calculated as Ce2O3, was 4wt%, the time was 0.5h, and the temperature was 30℃).

[0157] The parameters of sulfur transfer agent DB-4 are listed in Table 1.

[0158] Table 1

[0159]

[0160]

[0161] Test case

[0162] Take 0.5g of the sulfur transfer agent prepared in the above examples and comparative examples, and place it in a quartz tube fixed-bed reactor with an inner diameter of 20mm. The two ends of the sulfur transfer agent bed are filled with quartz wool and quartz sand to fix the sulfur transfer agent bed in the isothermal section in the middle of the reactor. The temperature of the sulfur transfer agent bed is controlled by a thermocouple. The specific process of pretreatment and evaluation of the sulfur transfer agent to be tested is as follows:

[0163] (1) After the reactor temperature (650℃) stabilizes, the sulfur transfer agent is first pretreated in N2 atmosphere for 60 min to fully remove the adsorbed species on the surface of the sulfur transfer agent to be tested.

[0164] (2) After pretreatment, simulated flue gas containing SO2 was introduced for 10 min (gas composition data (mL / min): nitrogen: 1757; air: 143; sulfur dioxide: 100), and the adsorbed gas was collected and the concentration of SO2 in the adsorbed gas in real time was analyzed using an online infrared analyzer.

[0165] (3) Calculate the desulfurization efficiency = 100% × (S 脱硫前 -S 脱硫后 ) / S 脱硫前 The results are shown in Table 2. 脱硫前 S represents the volume concentration of SO2 in the simulated gas before desulfurization. 脱硫后 This indicates the volume concentration of SO2 in the simulated gas after desulfurization.

[0166] Table 2

[0167]

[0168]

[0169] Based on the above data, it can be seen that the method disclosed herein uses particles containing magnesium oxide and aluminum oxide in the exhaust gas of chlorine spray drying as raw materials to prepare a sulfur transfer carrier, and loads metal active components on it. The prepared sulfur transfer agent has wear index and desulfurization efficiency comparable to existing products.

[0170] Specifically, based on the comparison of Examples 1 to 3, it can be seen that when the total weight of magnesium and aluminum in the first material, calculated as oxides, and the weight ratio of magnesium in the second alkaline magnesium source slurry to aluminum in the acidic alumina colloid are within the preferred range of 1:(1-7):(1-20), the prepared sulfur transfer agent can maintain a low abrasion index while having a higher desulfurization efficiency. Based on the comparison of Examples 1 and 5 and 6, it can be seen that when the pH value of the mixture obtained from contact is within the preferred range of 8 to 11 and the weight ratio of the total weight of magnesium and aluminum in the chlorine-containing spray drying tail gas to magnesium in the first alkaline magnesium source slurry is within the preferred range of 1:(3-15), the desulfurization efficiency of the sulfur transfer agent can be further improved and the abrasion index can be reduced. Based on the comparison of Examples 1 and 4, it can be seen that when the reaction temperature is within the preferred range of 80 to 100°C, a higher desulfurization efficiency and a lower abrasion index can be obtained.

[0171] The preferred embodiments of this disclosure have been described in detail above. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0172] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0173] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A method for preparing a sulfur transfer carrier, characterized in that, The method includes the following steps: S1. The chlorine-containing spray drying tail gas is contacted with the first alkaline magnesium source slurry and reacted to obtain the first material; The pH value of the mixture obtained by the contact is 7-12, and the reaction temperature is 70-120°C; S2. Mix the first material, the second alkaline magnesium source slurry, and the acidic alumina colloid to obtain the second material; S3. Spray dry and calcinate the second material; The exhaust gas from the chlorine-containing spray drying contains particles containing aluminum oxide and magnesium oxide.

2. The method according to claim 1, wherein, The chlorine-containing spray drying exhaust gas is the spray drying exhaust gas generated during the preparation of the sulfur transfer carrier.

3. The method according to claim 1, wherein, The temperature of the chlorine-containing spray-dried exhaust gas is 140–250°C. In the exhaust gas from the chlorine-containing spray drying process, the concentration of chlorine is 200–2000 mg / m³. 3 The total concentration of the magnesium oxide and the aluminum oxide is 500–5000 mg / m³. 3 ; The average particle size of the particles is 2–10 μm; The content of magnesium oxide is 30-60% by weight and the content of aluminum oxide is 40-70% by weight relative to the total weight of the particles.

4. The method according to claim 1, wherein, In step S1, the total weight of magnesium and aluminum in the chlorine-containing spray drying tail gas, calculated as oxides, is 1:(0.5-20) to the weight of magnesium in the first alkaline magnesium source slurry, preferably 1:(3-15).

5. The method according to claim 1, wherein, In step S1, the pH value of the mixture obtained by contact is 8 to 11; Optionally, the reaction temperature is 70–100°C; Optionally, the reaction time is 0.5 to 3 hours.

6. The method according to claim 1, wherein, The method for preparing the acidic alumina colloid includes: mixing a dispersion containing boehmite and / or aluminum sol with an acid, wherein the molar ratio of the acid to aluminum is 0.2 to 0.7; Optionally, the solid content of the dispersion is 5-20% by weight.

7. The method according to claim 1, wherein, In step S2, the total weight of magnesium and aluminum in the first material, and the weight ratio of magnesium in the second alkaline magnesium source slurry to aluminum in the acidic alumina colloid, based on oxides, is 1:(0.5-20):(1-30). Optionally, the mixing method is pulping, which is carried out under stirring conditions for 5 to 120 minutes.

8. The method according to claim 1, wherein, In step S3, the conditions for spray drying include: the outlet temperature is 140-250°C; The roasting conditions include a temperature of 300–700°C and a time of 0.5–10 h.

9. The method according to claim 1, wherein, Both the first and second alkaline magnesium source slurries contain an alkaline magnesium source, which includes magnesium hydroxide and / or magnesium oxide. The magnesium oxide has a citric acid value of 100–200s when tested at 30°C. -1 .

10. The method according to claim 9, wherein, The solid content of the first alkaline magnesium source slurry and the second alkaline magnesium source slurry are 0.3-30% by weight, and the pH value is 9-12.5, respectively.

11. A method for preparing a sulfur transfer agent, characterized in that, The method includes: reacting a sulfur transfer carrier prepared by the method according to any one of claims 1 to 10 with a solution containing an active metal source.

12. The method according to claim 11, wherein, The active metal source includes one or more of the following: cerium source, lanthanide metal source, manganese source, copper source, zirconium source, and iron source; Optionally, the contact reaction may be carried out by supersaturated impregnation under the following conditions: a temperature of 10–80°C and a time of 5–90 min.

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