Medium and low temperature organic sulfur hydrolytic agent applied to dry purification of coal gas and preparation method of medium and low temperature organic sulfur hydrolytic agent

Abstract

The invention discloses a medium and low temperature organic sulfur hydrolytic agent applied to coal gas dry purification and a preparation method thereof, and relates to the technical field of coal gas purification and industrial catalysis, the hydrolytic agent comprises the following components: gamma-Al203, pseudo-boehmite, a pore forming agent, an active agent, an auxiliary agent, an adhesive and water. According to the medium-low temperature organic sulfur hydrolytic agent applied to dry purification of coal gas and the preparation method thereof, an alkali metal element is adopted as an active agent, and the characteristic that the alkali metal element can provide a large number of alkaline reaction sites is utilized, so that organic sulfur molecules are promoted to be preferentially adsorbed with the hydrolytic agent to generate hydrolysis reaction; meanwhile, sodium metavanadate is added as an active auxiliary agent, so that the low-temperature activity of the hydrolysis catalyst is further optimized.

Description

Technical Field

[0001] The invention relates to the technical field of coal gas purification and industrial catalysis, and in particular to a medium-low temperature organic sulfur hydrolyzing agent used for dry purification of coal gas and a preparation method thereof. Background Art

[0002] Gaseous sulfides are often present in by-product tail gas of the steel industry, such as blast furnace gas and coke oven gas, which can cause equipment corrosion and catalyst poisoning and deactivation, and reduce product quality. At the same time, they are gradually oxidized in the atmosphere to form sulfur oxides, leading to environmental pollution problems such as acid rain. Therefore, the country vigorously promotes the implementation of ultra-low emissions in the steel industry, and proposes to carry out source control of fine desulfurization of different types of gas such as coke oven gas and blast furnace gas, which can ensure ultra-low emissions of SO2 for downstream users and avoid the construction of scattered terminal treatment facilities. It is of great significance to promote the ultra-low emission transformation of the entire process of the steel industry and promote the green development of the steel industry. Among them, carbonyl sulfide gas (COS) and carbon disulfide (CS2) are difficult to be effectively removed by conventional removal methods due to their chemical stability. The hydrolysis method has the advantages of low reaction temperature, no consumption of hydrogen source, and few side reactions. It is one of the most promising organic sulfur removal technologies. The hydrolyzing agent is the core of the hydrolysis reaction, which requires the hydrolyzing agent to have the characteristics of high activity, good selectivity, and anti-poisoning performance, which is a difficult problem for the hydrolyzing agent. Whether it is the conventional organic sulfur hydrolysis catalyst widely used in the current chemical industry or the newly developed organic sulfur hydrolysis catalyst specifically for coal gas, its catalytic system is still mainly weakly alkaline carbonates or transition metal oxides supported by metal oxides such as aluminum oxide, titanium oxide, and iron oxide. However, the hydrolysis reaction temperature of these catalysts is high, the sulfate resistance is poor, and they are easy to deactivate. The catalysts need to be replaced frequently, which increases the cost of the desulfurization process.

[0003] Therefore, the research and development of low-temperature, high-efficiency, stable-performance, and long-life organic sulfur medium- and low-temperature hydrolysis catalysts that can be used in the field of coal gas purification has become a hot topic in this technical research field, and is of great significance to energy conservation, emission reduction, pollution reduction, and carbon reduction in my country's steel industry. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a medium- and low-temperature organic sulfur hydrolyzing agent for dry gas purification and a preparation method thereof, which solves the problems mentioned in the above background technology.

[0005] To achieve the above objectives, the present invention is implemented through the following technical scheme: a medium-low temperature organic sulfur hydrolyzer used for dry gas purification, the hydrolyzer comprising the following components: γ-Al2O3, pseudo-boehmite, a pore-forming agent, an active agent, an auxiliary agent, a binder, and water.

[0006] Preferably, the components are calculated in weight percentage as follows: the amount of pseudo-boehmite added is 6% to 12% of the mass of γ-Al203; the amount of the pore-forming agent added is 4% to 10% of the mass of γ-Al203; the amount of the active agent added is 15% to 25% of the mass of γ-Al203; the amount of the auxiliary agent added is 1% to 3% of the mass of γ-Al203; the amount of the binder added is 20% to 30% of the mass of γ-Al203; and an appropriate amount of water.

[0007] A method for preparing a medium-low temperature organic sulfur hydrolyzing agent for dry gas purification, specifically comprising the following preparation steps:

[0008] Step 1: Mix the pore-forming agent, the active agent, the auxiliary agent and an appropriate amount of warm water in proportion and dissolve them, and stir them continuously to obtain a uniformly mixed solution;

[0009] Step 2: uniformly mix a certain proportion of γ-Al2O3 and pseudo-boehmite into the solution obtained in step 1, and continuously stir to obtain a uniformly mixed material;

[0010] Step 3: slowly add the binder to the mixed material in step 2, stir, and let stand for 40 to 60 minutes after mixing evenly to obtain the final mixed material;

[0011] Step 4: rolling and kneading the mixed material processed in step 3, adding it into a molding machine for extrusion molding after rolling evenly, so that the mixed material is bonded into a columnar molding material of uniform size;

[0012] Step 5: Place the columnar molding material obtained after the treatment in step 4 in a drying furnace at 100-120° C. for drying for 3-6 hours;

[0013] Step 6: The dried material obtained in step 5 is then roasted at a temperature of 500-700° C. for 5-6 hours. The cooled columnar catalyst is sieved to obtain the medium- and low-temperature hydrolysis catalyst.

[0014] Preferably, the pore-forming agent is one or a mixture of sodium bicarbonate, urea, and ammonium bicarbonate.

[0015] Preferably, the active agent is one or a mixture of metatitanic acid, potassium carbonate, zirconium nitrate, and cerium nitrate.

[0016] Preferably, the active auxiliary agent is sodium metavanadate.

[0017] Preferably, the adhesive is sodium polyacrylate.

[0018] Preferably, the method for preparing the medium-low temperature organic sulfur hydrolyzing agent for dry gas purification further comprises pre-treating the pseudo-boehmite before use, and the specific treatment method is:

[0019] S1. Pour pseudo-boehmite into deionized water;

[0020] S2, pour in TiO2 powder and continue to dissolve to make a suspension mixture;

[0021] S3, placing in an ice water bath for vigorous stirring, and slowly adding ammonia water to the suspension mixture to adjust the pH value of the solution to 9-10;

[0022] S4, leaving it to stand for aging at room temperature for 18 to 24 hours, then decompressing and filtering, and then placing it in a drying oven at 100 to 105°C and drying to constant weight;

[0023] S5. After grinding, pass through a 40-50 mesh sieve, and place the powder sample in a muffle furnace at 450-500°C for 4-6 hours;

[0024] Among them, the mass ratio of pseudo-boehmite to TiO2 is 2:(0.8~1).

[0025] Beneficial Effects

[0026] The present invention provides a medium-low temperature organic sulfur hydrolyzing agent for dry gas purification and a preparation method thereof. Compared with the prior art, it has the following beneficial effects:

[0027] (1) The medium-low temperature organic sulfur hydrolyzing agent used in dry gas purification and its preparation method adopt alkali metal elements as active agents, and utilize the characteristics of alkali metal elements that can provide a large number of alkaline reaction sites to promote the organic sulfur molecules to preferentially adsorb to the hydrolyzing agent and then undergo a hydrolysis reaction; at the same time, sodium metavanadate is added as an active auxiliary agent to further optimize the low-temperature activity of the hydrolysis catalyst;

[0028] (2) The medium-low temperature organic sulfur hydrolyzer used in dry gas purification and its preparation method can be better soluble in the metal precursor by using materials such as sodium bicarbonate, urea, and ammonium bicarbonate as pore-enlarging agents. In addition, high-temperature calcination can release a large amount of gas, thereby increasing the specific surface area of ​​the hydrolysis catalyst and enriching its pore structure; thereby making the service life of the hydrolysis catalyst longer and the reaction performance more stable;

[0029] (3) The medium-low temperature organic sulfur hydrolyzer used in dry gas purification and its preparation method adopt source mixing and reasonably set the molar ratio of elements such as sodium, potassium, titanium and aluminum in the hydrolysis catalyst, thereby ensuring the uniformity of the material and improving the anti-poisoning performance of the hydrolysis catalyst.

[0030] To sum up, in this technical scheme, on the premise of improving the uniformity of the composition, performance stability and specific surface area of ​​the columnar alumina hydrolyzing agent and having a developed pore structure, active agents and auxiliary agents are introduced to promote the preferential adsorption of organic sulfur molecules with the hydrolyzing agent and then the hydrolysis reaction, so that it can show low temperature and high efficiency, stable performance, strong anti-poisoning performance and longer service life in coal gas purification. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 Schematic diagram of the effect of temperature on the conversion rate of the hydrolysis catalyst CS2 in laboratory tests of Examples 1 to 5 of the present invention;

[0032] Figure 2 Schematic diagram of the effect of temperature on the COS conversion rate of the hydrolysis catalyst in laboratory tests of Examples 1 to 5 of the present invention. DETAILED DESCRIPTION

[0033] 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.

[0034] The method for preparing the medium-low temperature organic sulfur hydrolyzing agent used for dry gas purification also includes pre-treating the pseudo-boehmite before use, and the specific treatment method is:

[0035] S1. Pour pseudo-boehmite into deionized water;

[0036] S2, pour in TiO2 powder and continue to dissolve to make a suspension mixture;

[0037] S3, placing in an ice water bath for vigorous stirring, and slowly adding ammonia water to the suspension mixture to adjust the pH value of the solution to 9;

[0038] S4, leaving it to stand at room temperature for 18 to 24 hours, then decompressing and filtering, and then placing it in a drying oven at 100°C and drying to constant weight;

[0039] S5, after grinding, pass through a 40-mesh sieve, and place the powder sample in a muffle furnace at 450°C for 4 hours;

[0040] Among them, the mass ratio of pseudo-boehmite to TiO2 is 2:1.

[0041] Embodiment 1

[0042] A medium-low temperature organic sulfur hydrolysis catalyst used for dry gas purification, and its preparation method is as follows:

[0043] Step 1: 100 g of ammonium bicarbonate, 70 g of potassium carbonate, 130 g of metatitanic acid, 30 g of sodium metavanadate and an appropriate amount of warm water are mixed and dissolved in proportion, and stirred continuously to obtain a uniformly mixed solution;

[0044] Step 2: Evenly mix 1 kg of γ-Al2O3 and 100 g of pseudo-boehmite into the solution obtained in step 1, and stir continuously to obtain a uniformly mixed material;

[0045] Step 3: slowly add 300 g of adhesive to the mixed material in step 2, stir, mix evenly and let stand for 40 minutes to obtain the final mixed material;

[0046] Step 4: rolling and kneading the mixed material processed in step 3, adding it into a molding machine for extrusion molding after rolling evenly, so that the mixed material is bonded into a columnar molding material of uniform size;

[0047] Step 5: Place the columnar molding material obtained after the treatment in step 4 in a drying furnace at 100° C. for drying for 3 hours;

[0048] Step 6: The dried material obtained in step 5 is then calcined at a temperature of 500° C. for 5 hours. The cooled columnar catalyst is sieved to obtain the medium- and low-temperature hydrolysis catalyst A.

[0049] Embodiment 2

[0050] A medium-low temperature organic sulfur hydrolysis catalyst used for dry gas purification, and its preparation method is as follows:

[0051] Step 1: 80 g urea, 60 g potassium carbonate, 100 g titanic acid, 50 g cerium nitrate, 20 g sodium metavanadate and an appropriate amount of warm water are mixed and dissolved in proportion, and stirred continuously to obtain a uniformly mixed solution;

[0052] Step 2: Evenly mix 1 kg of γ-Al2O3 and 110 g of pseudo-boehmite into the solution obtained in step 1, and stir continuously to obtain a uniformly mixed material;

[0053] Step 3: slowly add 300 g of binder to the mixed material in step 2, stir, mix evenly and let stand for 45 minutes to obtain the final mixed material;

[0054] Step 4: rolling and kneading the mixed material processed in step 3, adding it into a molding machine for extrusion molding after rolling evenly, so that the mixed material is bonded into a columnar molding material of uniform size;

[0055] Step 5: Place the columnar molding material obtained after the treatment in step 4 in a drying furnace at 110° C. for drying for 4 hours;

[0056] Step 6: The dried material obtained in step 5 is then calcined at a temperature of 600° C. for 6 hours. The cooled columnar catalyst is sieved to obtain the medium- and low-temperature hydrolysis catalyst B.

[0057] Embodiment 3

[0058] A medium-low temperature organic sulfur hydrolysis catalyst used for dry gas purification, and its preparation method is as follows:

[0059] Step 1: 80 g of sodium bicarbonate, 50 g of potassium carbonate, 100 g of metatitanic acid, 40 g of zirconium nitrate, 20 g of sodium metavanadate and an appropriate amount of warm water are mixed and dissolved in proportion, and stirred continuously to obtain a uniformly mixed solution;

[0060] Step 2: Evenly mix 1 kg of γ-Al2O3 and 100 g of pseudo-boehmite into the solution obtained in step 1, and stir continuously to obtain a uniformly mixed material;

[0061] Step 3: slowly add 300 g of binder to the mixed material in step 2, stir, mix evenly and let stand for 50 minutes to obtain the final mixed material;

[0062] Step 4: rolling and kneading the mixed material processed in step 3, adding it into a molding machine for extrusion molding after rolling evenly, so that the mixed material is bonded into a columnar molding material of uniform size;

[0063] Step 5: Place the columnar molding material obtained after the treatment in step 4 in a drying furnace at 120° C. for drying for 5 hours;

[0064] Step 6: The dried material obtained in step 5 is then calcined at a temperature of 700° C. for 5 hours. The cooled columnar catalyst is sieved to obtain the medium- and low-temperature hydrolysis catalyst C.

[0065] Embodiment 4

[0066] A medium-low temperature organic sulfur hydrolysis catalyst used for dry gas purification, and its preparation method is as follows:

[0067] Step 1: 80 g of ammonium bicarbonate, 70 g of potassium carbonate, 130 g of titanic acid, 40 g of zirconium nitrate, 20 g of sodium metavanadate and an appropriate amount of warm water are mixed and dissolved in proportion, and stirred continuously to obtain a uniformly mixed solution;

[0068] Step 2: Evenly mix 1 kg of γ-Al2O3 and 100 g of pseudo-boehmite into the solution obtained in step 1, and stir continuously to obtain a uniformly mixed material;

[0069] Step 3: slowly add 300 g of adhesive to the mixed material in step 2, stir, mix evenly and let stand for 60 minutes to obtain the final mixed material;

[0070] Step 4: rolling and kneading the mixed material processed in step 3, adding it into a molding machine for extrusion molding after rolling evenly, so that the mixed material is bonded into a columnar molding material of uniform size;

[0071] Step 5: Place the columnar molding material obtained after the treatment in step 4 in a drying furnace at 120° C. for drying for 6 hours;

[0072] Step 6: The dried material obtained in step 5 is then roasted at a temperature of 700° C. for 6 hours. The cooled columnar catalyst is sieved to obtain the medium- and low-temperature hydrolysis catalyst D.

[0073] Embodiment 5

[0074] A medium-low temperature organic sulfur hydrolysis catalyst used for dry gas purification, and its preparation method is as follows:

[0075] Step 1: 80 g of ammonium bicarbonate, 70 g of potassium carbonate, 130 g of titanic acid, 40 g of cerium nitrate, 20 g of sodium metavanadate and an appropriate amount of warm water are mixed and dissolved in proportion, and stirred continuously to obtain a uniformly mixed solution;

[0076] Step 2: Evenly mix 1 kg of γ-Al2O3 and 110 g of pseudo-boehmite into the solution obtained in step 1, and stir continuously to obtain a uniformly mixed material;

[0077] Step 3: slowly add 300 g of adhesive to the mixed material in step 2, stir, mix evenly and let stand for 60 minutes to obtain the final mixed material;

[0078] Step 4: rolling and kneading the mixed material processed in step 3, adding it into a molding machine for extrusion molding after rolling evenly, so that the mixed material is bonded into a columnar molding material of uniform size;

[0079] Step 5: Place the columnar molding material obtained after the treatment in step 4 in a drying furnace at 120° C. for drying for 3 hours;

[0080] Step 6: The dried material obtained in step 5 is then roasted at a temperature of 700° C. for 5 hours. The cooled columnar catalyst is sieved to obtain the medium- and low-temperature hydrolysis catalyst E.

[0081] Activity evaluation results of hydrolysis catalyst samples:

[0082] The hydrolysis catalyst was evaluated and tested in the laboratory using simulated coke oven gas. The experimental data are shown in Figure 1 , 2 The specific operating conditions are as follows: CO 5.0%, CO2 2.0%, CH4 25%, H2 60.0%, 02 1.0%, CS2 100ppm, COS200ppm, N2 as balance gas, space velocity 2000h -1 .

[0083] Meanwhile, the contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0084] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0085] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A medium-low temperature organic sulfur hydrolyzing agent used for dry gas purification, characterized in that: The hydrolyzing agent comprises the following components: gamma-Al2O3, pseudo-boehmite, a pore-forming agent, an active agent, an auxiliary agent, a binder and water.

2. The medium-low temperature organic sulfur hydrolyzing agent for dry gas purification according to claim 1, characterized in that: The components are calculated in percentage by weight as follows: the amount of pseudo-boehmite added is 6% to 12% of the mass of γ-Al203; the amount of pore-forming agent added is 4% to 10% of the mass of γ-Al203; the amount of activator added is 15% to 25% of the mass of γ-Al203; the amount of auxiliary agent added is 1% to 3% of the mass of γ-Al203; the amount of binder added is 20% to 30% of the mass of γ-Al203; and an appropriate amount of water.

3. A method for preparing a medium-low temperature organic sulfur hydrolyzing agent for dry gas purification according to claim 1, characterized in that: The specific preparation steps include: Step 1: Mix the pore-forming agent, the active agent, the auxiliary agent and an appropriate amount of warm water in proportion and dissolve them, and stir them continuously to obtain a uniformly mixed solution; Step 2: uniformly mix a certain proportion of γ-Al2O3 and pseudo-boehmite into the solution obtained in step 1, and continuously stir to obtain a uniformly mixed material; Step 3: slowly add the binder to the mixed material in step 2, stir, and let stand for 40 to 60 minutes after mixing evenly to obtain the final mixed material; Step 4: rolling and kneading the mixed material processed in step 3, adding it into a molding machine for extrusion molding after rolling evenly, so that the mixed material is bonded into a columnar molding material of uniform size; Step 5: Place the columnar molding material obtained after the treatment in step 4 in a drying furnace at 100-120° C. for drying for 3-6 hours; Step 6: The dried material obtained in step 5 is then roasted at a temperature of 500-700° C. for 5-6 hours. The cooled columnar catalyst is sieved to obtain the medium- and low-temperature hydrolysis catalyst.

4. The method for preparing a medium-low temperature organic sulfur hydrolyzing agent for dry gas purification according to claim 3, characterized in that: The pore-forming agent is one or a mixture of sodium bicarbonate, urea and ammonium bicarbonate.

5. The method for preparing a medium-low temperature organic sulfur hydrolyzing agent for dry gas purification according to claim 3, characterized in that: The active agent is one or a mixture of metatitanic acid, potassium carbonate, zirconium nitrate and cerium nitrate.

6. The method for preparing a medium-low temperature organic sulfur hydrolyzing agent for dry gas purification according to claim 3, characterized in that: The active auxiliary agent is sodium metavanadate.

7. The method for preparing a medium-low temperature organic sulfur hydrolyzing agent for dry gas purification according to claim 3, characterized in that: The adhesive is sodium polyacrylate.

8. The method for preparing a medium-low temperature organic sulfur hydrolyzing agent for dry gas purification according to claim 3, characterized in that: The method for preparing the medium-low temperature organic sulfur hydrolyzing agent used for dry gas purification also includes pre-treating the pseudo-boehmite before use, and the specific treatment method is: S1. Pour pseudo-boehmite into deionized water; S2, pour in TiO2 powder and continue to dissolve to make a suspension mixture; S3, placing in an ice water bath for vigorous stirring, and slowly adding ammonia water to the suspension mixture to adjust the pH value of the solution to 9-10; S4, leaving it to stand for aging at room temperature for 18 to 24 hours, then decompressing and filtering, and then placing it in a drying oven at 100 to 105°C and drying to constant weight; S5. After grinding, pass through a 40-50 mesh sieve, and place the powder sample in a muffle furnace at 450-500°C for 4-6 hours; Among them, the mass ratio of pseudo-boehmite to TiO2 is 2:(0.8~1).

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