Carbon material for removing hydrogen sulfide and preparation method and application thereof

Abstract

The present invention relates to the technical field of carbon material preparation, and discloses a carbon material for removing hydrogen sulfide, a preparation method thereof, and the use of the carbon material in treating hydrogen sulfide in hydrogen. The method comprises: in the presence of a solvent, contacting a metal precursor with lignin, then subjecting the obtained suspension to a precipitation reaction with a precipitant, and then roasting the obtained solid product, impregnating the roasted product with a metal alkali solution, and then carbonizing it; the metal in the metal precursor includes copper and zinc. The method uses cheap lignin as a carbon source and utilizes its high carbon content to prepare a carbon material for removing hydrogen sulfide loaded with active metal copper and zinc. The carbon material has a high specific surface area and a rich mesoporous structure, which is more conducive to removing hydrogen sulfide from hydrogen. In addition, the method has a simple preparation process, cheap raw materials, low preparation cost, and is more conducive to wide application.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon material preparation, in particular to a carbon material for removing hydrogen sulfide, a preparation method thereof, and application of the carbon material in treating hydrogen sulfide in hydrogen. Background Art

[0002] With the widespread adoption of fuel cells, hydrogen purity standards are attracting increasing research attention. Hydrogen sulfide, a common toxic and hazardous substance in industrial and agricultural production, is a major impurity in hydrogen. This is due to the fact that hydrogen is often sourced from coal or petroleum reforming. Hydrogen sulfide's poisoning effect on fuel cells is extremely rapid and irreversible, as the platinum metal in the electrode catalyst readily reacts with it.

[0003] CN101262928A discloses a desulfurization adsorption material, which uses zinc, copper, and aluminum oxides obtained by precipitation and roasting of zinc, copper, and aluminum precursors to remove sulfides. However, the specific surface area of ​​the material is relatively low, ranging from 80 to 160 m 2 / g, which is not conducive to the diffusion of sulfide in the adsorbent, resulting in limited adsorption performance of the material.

[0004] CN108295809A discloses a desulfurization adsorption material, which loads active components such as zinc, copper, and cobalt on a mesoporous molecular sieve, and then mixes and roasts them with a modified microporous molecular sieve and alumina to obtain a desulfurization adsorbent. However, the material requires complex components and cumbersome steps, which is not conducive to production.

[0005] Activated carbon, with its well-developed pore structure, large specific surface area, and abundant surface chemical groups, is a type of carbon material with strong specific adsorption capacity. Therefore, it is often used as an adsorbent and catalyst carrier.

[0006] D, Hoon Sub Song A et al. (Hydrogen sulfide adsorption on nano-sized zincoxide / reduced graphite oxide composite at ambient conditions - Science Direct [J]. Applied Surface Science, 2013, 276(3): 646-652.) loaded zinc oxide onto graphene and used it as a sulfide adsorption material. This material utilizes the high specific surface area of ​​graphene to effectively disperse zinc oxide, but the high cost of graphene as a carrier makes it difficult to produce on a large scale.

[0007] CN103521176A discloses a desulfurization adsorption material, which is prepared by mixing activated carbon, copper sulfate, high-alumina bauxite, magnesium oxide, calcium oxide, sodium carbonate, and modified attapulgite in a certain proportion. However, the preparation of the modified attapulgite required for this material is cumbersome and not conducive to industrial production.

[0008] CN106925229A discloses a desulfurization material that directly utilizes lignin as a carbon source and iron and zinc as active components. This material first uses lignin as a raw material to prepare lignin activated carbon, and then hydrothermally mixes a metal active component solution, a surfactant, and an alkaline solution to produce the desulfurization material. This desulfurization material preparation process is simple, has good desulfurization effects, improves the precision of activated carbon desulfurization, and is resistant to high temperatures. However, this method requires the use of a surfactant, and the use of the surfactant and the hydrothermal process of mixing the alkali solution to produce the lignin are cumbersome, which is not conducive to reducing production costs. Summary of the Invention

[0009] The purpose of the present invention is to overcome the above-mentioned problems existing in the prior art and provide a carbon material for removing hydrogen sulfide, a preparation method thereof, and the application of the carbon material in treating hydrogen sulfide in hydrogen. The carbon material has excellent hydrogen sulfide adsorption performance, and its preparation process is simple, the raw materials are cheap, and the preparation cost is low.

[0010] In order to achieve the above object, the first aspect of the present invention provides a method for preparing a carbon material for removing hydrogen sulfide, the method comprising:

[0011] (1) contacting a metal precursor with lignin in the presence of a solvent to obtain a suspension;

[0012] (2) subjecting the suspension to a precipitation reaction with a precipitant to obtain a solid product;

[0013] (3) calcining the solid product to obtain a calcined product;

[0014] (4) impregnating the calcined product with a metal alkali solution and then carbonizing it;

[0015] The metals in the metal precursor include copper and zinc.

[0016] The second aspect of the present invention provides a carbon material for removing hydrogen sulfide prepared by the method described in the first aspect.

[0017] The third aspect of the present invention provides use of the carbon material for removing hydrogen sulfide according to the second aspect in treating hydrogen sulfide in hydrogen.

[0018] Through the above technical solution, the method provided by the present invention uses inexpensive lignin as a carbon source, taking advantage of its high carbon content. A metal precursor is contacted with lignin, followed by a precipitation reaction with a precipitant and then calcined. The calcined product is impregnated with a metal alkaline solution and finally carbonized to obtain a carbon material for hydrogen sulfide removal loaded with active metals copper and zinc. This carbon material has a high specific surface area and a rich mesoporous structure, which is more conducive to removing hydrogen sulfide from hydrogen. In addition, the method has a simple preparation process, inexpensive raw materials, and low preparation cost, making it more suitable for wide application. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a N2 adsorption-desorption isotherm diagram of the carbon material prepared in Example 1;

[0020] Figure 2 is a BJH pore size distribution curve of the carbon material prepared in Example 1;

[0021] Figure 3 、 Figure 4 and Figure 5 This is the XPS graph of the carbon material prepared in Example 1. DETAILED DESCRIPTION

[0022] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0023] A first aspect of the present invention provides a method for preparing a carbon material for removing hydrogen sulfide, the method comprising:

[0024] (1) contacting a metal precursor with lignin in the presence of a solvent to obtain a suspension;

[0025] (2) subjecting the suspension to a precipitation reaction with a precipitant to obtain a solid product;

[0026] (3) calcining the solid product to obtain a calcined product;

[0027] (4) impregnating the calcined product with a metal alkali solution and then carbonizing it;

[0028] The metals in the metal precursor include copper and zinc.

[0029] During the research process, the inventors of the present invention discovered that since lignin is a complex organic polymer that forms an important structural material in the supporting tissues of vascular plants and some algae, and chemically, lignin is a cross-linked phenolic polymer with a relatively high carbon content, and the raw materials are abundant and inexpensive, it can be used as an excellent raw material for synthesizing activated carbon-based adsorption materials.

[0030] According to some embodiments of the present invention, in step (1), the metal precursor is contacted with lignin in the presence of a solvent to obtain a suspension. The present invention does not particularly limit the manner of contact, as long as a suspension can be obtained, the purpose of the present invention can be achieved. Preferably, the contact conditions include: stirring, a temperature of 15-35°C, preferably 20-30°C; and a time of 5-30 minutes, preferably 10-20 minutes.

[0031] According to some embodiments of the present invention, in order to further improve the hydrogen sulfide adsorption performance of the prepared carbon material, preferably, in step (1), the contact includes: first mixing the metal precursor with the solvent to obtain a metal precursor solution, and then mixing the metal precursor solution with lignin for a second time to obtain the suspension.

[0032] According to some embodiments of the present invention, there is no particular limitation on the type of the solvent, as long as it can form a suspension. Preferably, the solvent is water and / or ethanol, more preferably water. There is no particular limitation on the amount of the solvent, as long as it can form a suspension.

[0033] According to some embodiments of the present invention, preferably, the first mixing includes constant temperature stirring; more preferably, the constant temperature stirring conditions include: temperature of 20-30° C., time of 10-20 minutes.

[0034] According to some embodiments of the present invention, preferably, the second mixing conditions include: carrying out under stirring conditions, a temperature of 20-30° C., and a time of 10-20 minutes.

[0035] According to some embodiments of the present invention, the metal in the metal precursor includes copper and zinc. Preferably, the molar ratio of copper to zinc in the metal precursor, calculated as the elements, is 1:(0.2-5), preferably 1:(0.7-1.1). A molar ratio of copper to zinc within the above-defined range can result in an adsorbent having better hydrogen sulfide adsorption performance.

[0036] According to some embodiments of the present invention, the metal in the metal precursor preferably further comprises at least one of aluminum, manganese, and nickel. More preferably, the molar ratio of copper, aluminum, manganese, and nickel in the metal precursor, calculated as elements, is 1:(0-1):(0-1):(0-1), and further preferably 1:(0.1-0.5):(0.1-0.5):(0.1-0.5). These preferred embodiments are beneficial for further improving the hydrogen sulfide adsorption performance of the adsorbent.

[0037] According to some embodiments of the present invention, the metal precursor may be selected from a wide range of types, and conventional water-soluble metal salts in the art may be used. Preferably, the metal precursor is a chloride and / or nitrate containing the metal.

[0038] According to some embodiments of the present invention, the selection range of the lignin is relatively wide, and conventional lignin in the art can be used. Preferably, the lignin is alkali-washed lignin.

[0039] According to some embodiments of the present invention, preferably, the amount of the metal precursor and lignin used in the prepared carbon material is such that, based on the total amount of the carbon material, the carbon content is 40-70 wt%, preferably 45-67 wt%, and the metal content, calculated as oxide, is 30-60 wt%, preferably 33-55 wt%.

[0040] According to some embodiments of the present invention, in step (2), the suspension is subjected to a precipitation reaction with a precipitant to obtain a solid product. The precipitant may be selected from a wide range of types and is not particularly limited in the present invention. Preferably, the precipitant is at least one of sodium hydroxide, potassium hydroxide, sodium bicarbonate, and potassium bicarbonate.

[0041] According to some embodiments of the present invention, preferably, the precipitant is provided in the form of a solution.

[0042] According to some embodiments of the present invention, preferably, the molar ratio of the precipitant to the total amount of the metal precursor is 2-8:1, preferably 3-6:1.

[0043] According to some embodiments of the present invention, preferably, the precipitation reaction conditions include: being carried out under stirring at a temperature of 15-35°C, preferably 20-30°C; and for 5-20 minutes, preferably 10-15 minutes.

[0044] According to some embodiments of the present invention, preferably, the method further comprises performing suction filtration after the precipitation reaction to obtain the solid product.

[0045] According to some embodiments of the present invention, in step (3), the solid product is calcined to obtain a calcined product. Preferably, the calcination conditions include: a calcination temperature of 200-600°C, preferably 350-500°C; and a calcination time of 150-300 minutes, preferably 180-240 minutes.

[0046] According to some embodiments of the present invention, preferably, the calcination is performed under an inert atmosphere, and the inert atmosphere is provided by at least one of nitrogen, argon, helium and neon.

[0047] According to some embodiments of the present invention, in step (4), the calcined product is impregnated with a metal alkaline solution and then carbonized. Impregnating the calcined product with a metal alkaline solution helps activate the carbonization process of lignin, thereby forming a structured material with a high specific surface area. It also helps to increase the dispersion of the metal active components in the carbon material, thereby improving the carbon material's adsorption of hydrogen sulfide.

[0048] According to some embodiments of the present invention, the metal base in the metal base solution can be selected from a wide range, and conventional metal bases in the art can be used. Preferably, the metal base is selected from sodium hydroxide and / or potassium hydroxide.

[0049] According to some embodiments of the present invention, preferably, in step (4), the mass ratio of the metal base to the lignin is 1.5-5:1, preferably 1-2:1.

[0050] According to some embodiments of the present invention, preferably, the carbonization conditions include: a carbonization temperature of 600-1200°C, preferably 800-1000°C; and a carbonization time of 100-270 minutes, preferably 120-240 minutes. Carbonization conditions within the above preferred ranges are conducive to achieving complete carbonization of lignin in a relatively short period of time, while a carbonization temperature that is too low cannot completely convert the lignin into activated carbon.

[0051] According to some embodiments of the present invention, preferably, the carbonization is performed under an inert atmosphere provided by at least one of nitrogen, argon, helium and neon.

[0052] According to some embodiments of the present invention, preferably, the method further comprises drying after the impregnation and then performing the carbonization, and the drying temperature is 40-100°C.

[0053] According to some embodiments of the present invention, preferably, the method further comprises washing the product obtained by carbonization in step (4) and then drying it. There is no particular limitation on the manner of washing, and conventional washing methods in the art can be used, as long as the sodium ions and / or potassium ions can be cleaned. Preferably, the washing comprises: dispersing the product obtained by carbonization in step (4) in a washing solvent, more preferably, the washing solvent is water. In the method provided by the present invention, the washing can wash out the sodium ions and / or potassium ions without adsorption from the pore structure of the carbonized lignin to increase the specific surface area of ​​the obtained carbon material.

[0054] According to some embodiments of the present invention, the method uses cheap lignin as a carbon source, utilizes its high carbon content, contacts a metal precursor with lignin, and then carries out a precipitation reaction with a precipitant and then roasts it. The roasted product is impregnated with a metal alkali solution, and finally carbonized to obtain a carbon material for removing hydrogen sulfide loaded with active metal copper and zinc. The preparation process is simple, the raw materials are cheap, and the preparation cost is low. Moreover, due to the impregnation of the metal alkali solution, the carbonization process of the lignin is fully activated, which is not only beneficial to improving the dispersion of the metal active components in the carbon material, but also beneficial to obtaining a carbon material with a high specific surface area and a rich mesoporous structure.

[0055] The second aspect of the present invention provides a carbon material for removing hydrogen sulfide prepared by the method described in the first aspect.

[0056] According to some embodiments of the present invention, preferably, based on the total amount of the carbon material, the carbon content in the carbon material is 40-70 weight %, preferably 45-67 weight %, and the metal content in terms of oxide is 30-60 weight %, preferably 33-55 weight %.

[0057] According to some embodiments of the present invention, the type and content of each component in the carbon material are determined by X-ray photoelectron spectroscopy (XPS). The X-ray photoelectron spectroscopy analyzer used is an ESCALab220i-XL type X-ray electron spectrometer equipped with Avantage V5.926 software produced by VG Scientific. The X-ray photoelectron spectroscopy analysis test conditions are as follows: the excitation source is monochromatic A1Kα X-ray, the power is 330W, and the basic vacuum during the analysis test is 3×10 -9 In addition, the electron binding energy was calibrated using the C1s peak (284.6 eV), and the subsequent peak separation software was XPSPEAK.

[0058] According to some embodiments of the present invention, preferably, there are at least two mesopore distribution peaks in the pore size distribution curve of the carbon material; more preferably, in the pore size distribution curve of the carbon material, there is a first mesopore distribution peak at 2.2-2.5 nm, and a second mesopore distribution peak at 4-4.5 nm.

[0059] According to some embodiments of the present invention, preferably, the BET specific surface area of ​​the carbon material is greater than 400 m 2 / g, preferably greater than 600m 2 / g, more preferably 650-1000m 2 / g.

[0060] In the present invention, the term "mesopore" is defined as a pore with a pore diameter in the range of 2-50 nm.

[0061] In the present invention, the term "mesopore distribution peak" refers to a mesopore distribution peak on a pore distribution curve obtained by calculating a desorption curve according to the Barrett-Joyner-Halenda (BJH) method.

[0062] According to some embodiments of the present invention, the pore structure properties of the material are determined using the BET test method. Specifically, a Quantachrome AS-6B analyzer is used for measurement. The specific surface area and pore volume of the material are obtained using the Brunauer-Emmett-Taller (BET) method, and the mesopore distribution curve is calculated from the desorption curve using the Barrett-Joyner-Halenda (BJH) method.

[0063] According to some embodiments of the present invention, the carbon material has a higher specific surface area and a rich mesoporous structure, which is more conducive to removing hydrogen sulfide from hydrogen.

[0064] The third aspect of the present invention provides use of the carbon material for removing hydrogen sulfide according to the second aspect in treating hydrogen sulfide in hydrogen.

[0065] According to some embodiments of the present invention, preferably, the carbon material for removing hydrogen sulfide is contacted with a mixed gas containing hydrogen and hydrogen sulfide. Preferably, the content of hydrogen sulfide in the mixed gas is 800-1200 ppm.

[0066] According to some embodiments of the present invention, preferably, the contact conditions include: a pressure of 1-4 MPa, a temperature of 200-400°C, a gas phase space velocity of the mixed gas of 200-600 h -1 .

[0067] According to some embodiments of the present invention, the carbon material can adsorb up to 168.4 mg·g of hydrogen sulfide (content 1000 ppm) under the conditions of a pressure of 2 MPa and a temperature of 300°C. -1 , with better hydrogen sulfide adsorption performance.

[0068] The present invention will be described in detail below by way of examples. In the following examples and comparative examples:

[0069] Unless otherwise specified, all reagents used in the present invention are of analytical grade and commercially available.

[0070] The lignin was purchased from innochem with the model / brand A87075.

[0071] The pore structure properties of the material were determined using the BET test method. Specifically, a Quantachrome AS-6B analyzer was used for measurement. The specific surface area and pore volume of the material were obtained using the Brunauer-Emmett-Taller (BET) method, and the mesopore distribution curve was calculated from the desorption curve using the Barrett-Joyner-Halenda (BJH) method.

[0072] The elements on the surface of the material were detected by X-ray photoelectron spectroscopy (XPS). The X-ray photoelectron spectrometer used was an ESCALab220i-XL X-ray spectrometer produced by VG Scientific and equipped with Avantage V5.926 software. The X-ray photoelectron spectroscopy test conditions were as follows: the excitation source was monochromatic A1Kα X-ray with a power of 330W, and the basic vacuum during the analysis was 3×10 -9 In addition, the electron binding energy was calibrated using the C1s peak (284.6 eV), and the subsequent peak separation software was XPSPEAK.

[0073] Examples 1-4 are used to illustrate carbon materials for removing hydrogen sulfide and their preparation methods.

[0074] Example 1

[0075] Step 1: Dissolve 1.6 g of copper chloride, 1.3 g of zinc chloride, and 0.8 g of aluminum nitrate in deionized water, heat to 30° C., and stir for 10 minutes to obtain a metal precursor solution (wherein, the molar ratio of copper, zinc, and aluminum is 1:0.8:0.3, calculated as elements);

[0076] Step 2: Immerse the metal precursor solution in 10 g of lignin and stir at 25° C. for 20 minutes to obtain a suspension;

[0077] Step 3: dissolving 5 g of potassium hydroxide in deionized water (wherein the molar ratio of potassium hydroxide to the total amount of the metal precursor is 3.6:1) to obtain a precipitant solution, and adding the prepared precipitant solution dropwise to the suspension, stirring at a constant temperature of 25° C. for 10 minutes, filtering, and drying to obtain material 1;

[0078] Step 4: calcining material 1 in a muffle furnace at 500° C. for 240 minutes to obtain material 2;

[0079] Step 5: dissolving 10 g of potassium hydroxide in deionized water to obtain a metal alkali solution, impregnating the metal alkali solution on the second material, and drying to obtain the third material;

[0080] Step 6: calcining the material 3 in a tube furnace at 800° C. under nitrogen protection for 120 minutes to obtain the material 4;

[0081] Step seven, the material is dispersed in water, washed, and then filtered, and the filter cake is dried at 90° C. to obtain a carbon material for removing hydrogen sulfide.

[0082] Characterization of materials:

[0083] Figure 1 is the N2 adsorption-desorption isotherm of the carbon material, Figure 2 The BJH pore size distribution curve of the carbon material is shown in Table 1. It can be seen from the figure that the carbon material has two mesoporous distribution peaks at 2.3nm and 4.1nm. The BET specific surface area is shown in Table 1.

[0084] The X-ray photoelectron spectroscopy (XPS) of the carbon material is shown in FIG. Figure 3 、 Figure 4 and Figure 5 As shown in the figure, it can be seen that the carbon material clearly contains ZnO (such as Figure 3 As shown), CuO (as Figure 4 As shown) and Al2O3 (as Figure 5 Based on the total amount of the carbon material, the carbon content in the carbon material is shown in Table 1.

[0085] Example 2

[0086] Step 1: dissolve 3.2 g of copper chloride, 2.4 g of zinc chloride, and 0.8 g of aluminum nitrate in deionized water, heat to 30° C., and stir for 10 minutes to obtain a metal precursor solution (wherein, the molar ratio of copper, zinc, and aluminum is 1:0.74:0.16, calculated as elements);

[0087] Step 2: Immerse the metal precursor solution in 10 g of lignin and stir at 25° C. for 20 minutes to obtain a suspension;

[0088] Step 3: dissolving 15 g of potassium hydroxide in deionized water (wherein the molar ratio of potassium hydroxide to the total amount of the metal precursor is 6:1) to obtain a precipitant solution, and adding the prepared precipitant solution dropwise to the suspension, stirring at a constant temperature of 25° C. for 10 minutes, filtering, and drying to obtain material 1;

[0089] Step 4: calcining material 1 in a muffle furnace at 400° C. for 240 minutes to obtain material 2;

[0090] Step 5: dissolving 10 g of potassium hydroxide in deionized water to obtain a metal alkali solution, impregnating the metal alkali solution on the second material, and drying to obtain the third material;

[0091] Step 6: calcining the material 3 in a tube furnace at 900° C. under nitrogen protection for 120 minutes to obtain the material 4;

[0092] Step seven, the material is dispersed in water, washed, and then filtered, and the filter cake is dried at 90° C. to obtain a carbon material for removing hydrogen sulfide.

[0093] Characterization of materials:

[0094] BET analysis shows that the carbon material has two mesoporous distribution peaks at 2.3 nm and 4.1 nm. The BET specific surface area is shown in Table 1.

[0095] XPS testing showed that the carbon material clearly had XPS peaks of ZnO, CuO, and Al2O3. Based on the total amount of the carbon material, the carbon content of the carbon material is shown in Table 1.

[0096] Example 3

[0097] Step 1: Dissolve 1.6 g of copper nitrate, 1.3 g of zinc nitrate, and 0.8 g of aluminum nitrate in deionized water, heat to 30° C., and stir for 10 minutes to obtain a metal precursor solution (wherein, the molar ratio of copper, zinc, and aluminum is 1:0.8:0.44, calculated as elements);

[0098] Step 2: Immerse the metal precursor solution in 10 g of lignin and stir at 25° C. for 20 minutes to obtain a suspension;

[0099] Step 3: dissolving 5 g of potassium hydroxide in deionized water (wherein the molar ratio of potassium hydroxide to the total amount of the metal precursor is 4.5:1) to obtain a precipitant solution, and adding the prepared precipitant solution dropwise to the suspension, stirring at a constant temperature of 25° C. for 10 minutes, filtering, and drying to obtain material 1;

[0100] Step 4: calcining material 1 in a muffle furnace at 500° C. for 240 minutes to obtain material 2;

[0101] Step 5: dissolving 10 g of potassium hydroxide in deionized water to obtain a metal alkali solution, impregnating the metal alkali solution on the second material, and drying to obtain the third material;

[0102] Step 6: calcining the material 3 in a tube furnace at 900° C. under nitrogen protection for 120 minutes to obtain the material 4;

[0103] Step seven, the material is dispersed in water, washed, and then filtered, and the filter cake is dried at 90° C. to obtain a carbon material for removing hydrogen sulfide.

[0104] Characterization of materials:

[0105] BET analysis shows that the carbon material has two mesoporous distribution peaks at 2.3 nm and 4.1 nm. The BET specific surface area is shown in Table 1.

[0106] XPS testing showed that the carbon material clearly had XPS peaks of ZnO, CuO, and Al2O3. Based on the total amount of the carbon material, the carbon content of the carbon material is shown in Table 1.

[0107] Example 4

[0108] Step 1: dissolve 1.2 g of copper chloride, 1.0 g of zinc chloride, 0.8 g of aluminum nitrate, and 0.5 g of nickel nitrate in deionized water, heat to 30° C., and stir for 10 minutes to obtain a metal precursor solution (wherein, the molar ratio of copper, zinc, aluminum, and nickel, calculated as elements, is 1:0.82:0.42:0.3);

[0109] Step 2: Immerse the metal precursor solution in 10 g of lignin and stir at 25° C. for 20 minutes to obtain a suspension;

[0110] Step 3: dissolving 5 g of sodium hydroxide in deionized water (wherein the molar ratio of sodium hydroxide to the total amount of the metal precursor is 5.4:1) to obtain a precipitant solution, and adding the prepared precipitant solution dropwise to the suspension, stirring at a constant temperature of 25° C. for 10 minutes, filtering, and drying to obtain material 1;

[0111] Step 4, calcining material 1 in a muffle furnace at 350° C. for 240 minutes to obtain material 2;

[0112] Step 5: dissolving 20 g of potassium hydroxide in deionized water to obtain a metal alkali solution, impregnating the metal alkali solution on the material 2, and drying to obtain the material 3;

[0113] Step 6: calcining the material 3 in a tube furnace at 800° C. under nitrogen protection for 120 minutes to obtain the material 4;

[0114] Step seven, the material is dispersed in water, washed, and then filtered, and the filter cake is dried at 90° C. to obtain a carbon material for removing hydrogen sulfide.

[0115] Characterization of materials:

[0116] BET analysis shows that the carbon material has two mesoporous distribution peaks at 2.3 nm and 4.1 nm. The BET specific surface area is shown in Table 1.

[0117] XPS analysis showed that the carbon material clearly had XPS peaks of ZnO, CuO, Al2O3, and NiO. Based on the total amount of the carbon material, the carbon content of the carbon material is shown in Table 1.

[0118] Example 5

[0119] The method of Example 1 is followed, except that step seven is not performed. The remaining raw materials, steps, conditions, etc. are the same as those of Example 1, to obtain a carbon material for removing hydrogen sulfide.

[0120] Characterization of materials:

[0121] BET analysis shows that the carbon material has two mesoporous distribution peaks at 2.3 nm and 4.1 nm. The BET specific surface area is shown in Table 1.

[0122] XPS testing showed that the carbon material clearly had XPS peaks of ZnO, CuO, and Al2O3. Based on the total amount of the carbon material, the carbon content of the carbon material is shown in Table 1.

[0123] Comparative Example 1

[0124] Step 1: Dissolve 1.6 g of copper chloride, 1.3 g of zinc chloride, and 0.8 g of aluminum nitrate in deionized water, heat to 30° C., and stir for 10 minutes to obtain a metal precursor solution (wherein, the molar ratio of copper, zinc, and aluminum is 1:0.8:0.3, calculated as elements);

[0125] Step 2: Immerse the metal precursor solution in 10 g of lignin and stir at 25° C. for 20 minutes to obtain a suspension;

[0126] Step 3: dissolving 2.5 g of potassium hydroxide in deionized water (wherein the molar ratio of potassium hydroxide to the total amount of the metal precursor is 1.78:1) to obtain a precipitant solution, and adding the prepared precipitant solution dropwise to the suspension, stirring at a constant temperature of 25° C. for 10 minutes, filtering, and drying to obtain material 1;

[0127] Step 4: calcining material 1 in a muffle furnace at 400° C. for 240 minutes to obtain material 2;

[0128] Step 5: dissolving 2.5 g of potassium hydroxide in deionized water to obtain a metal alkali solution, impregnating the metal alkali solution on the material 2, and drying to obtain the material 3;

[0129] Step six, calcining material three in a tube furnace at 500° C. under nitrogen protection for 120 minutes to obtain a carbon material for removing hydrogen sulfide.

[0130] Characterization of materials:

[0131] XPS testing showed that the carbon material clearly had XPS peaks of ZnO, CuO, and Al2O3. Based on the total amount of the carbon material, the carbon content of the carbon material is shown in Table 1.

[0132] Comparative Example 2

[0133] The method of Example 1 is followed, except that step five is not performed. The remaining raw materials, steps, conditions, etc. are the same as those of Example 1, to obtain a carbon material for removing hydrogen sulfide.

[0134] Characterization of materials:

[0135] XPS testing showed that the carbon material clearly had XPS peaks of ZnO, CuO, and Al2O3. Based on the total amount of the carbon material, the carbon content of the carbon material is shown in Table 1.

[0136] Test Case

[0137] Adsorption of hydrogen sulfide: 10 mL of the carbon material for removing hydrogen sulfide prepared in Examples 1-5 was respectively taken as an adsorbent and loaded into a stainless steel reactor of Ø40 mm×2.5 mm×300 mm, and nitrogen was introduced for 2 h at a nitrogen gas phase space velocity of 10 h. -1 Under the conditions of pressure of 2MPa and temperature of 300℃, hydrogen was introduced with a gas phase space velocity of 500h -1 The content of hydrogen sulfide at the inlet was 1000 ppm. Samples were taken at the reactor outlet for chromatographic analysis. After adsorption saturation (the content of hydrogen sulfide at the outlet was higher than 10 ppm), the adsorption material was taken out and weighed, and the adsorption capacity was calculated. The results are shown in Table 1.

[0138] Comparative test example

[0139] The adsorption of hydrogen sulfide was carried out according to the method of the test example, except that the adsorbent was replaced by the carbon materials prepared in Comparative Examples 1-2, respectively. The results are shown in Table 1.

[0140] Table 1

[0141]

[0142] Note: The metals in the total metal content are calculated as oxides.

[0143] From the above results, it can be seen that the specific surface area of ​​the carbon material prepared by the method provided by the present invention can reach up to 890m 2 / g, and the maximum adsorption capacity of hydrogen sulfide can reach 168.4 mg·g -1 , with better hydrogen sulfide adsorption performance.

[0144] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A method for preparing a carbon material for removing hydrogen sulfide, the method comprising: (1) contacting a metal precursor with lignin in the presence of a solvent to obtain a suspension; (2) subjecting the suspension to a precipitation reaction with a precipitant to obtain a solid product; the molar ratio of the precipitant to the total amount of the metal precursor is 3-6:1; (3) calcining the solid product to obtain a calcined product; (4) impregnating the calcined product with a metal alkali solution and then carbonizing it; (5) washing the product obtained by carbonization in step (4) and then drying it; The metals in the metal precursor include copper and zinc; In the metal precursor, the molar ratio of copper to zinc is 1:(0.2-0.82) based on the elements.

2. The method according to claim 1, wherein The amounts of the metal precursor and lignin used are such that the carbon content in the prepared carbon material is 40-70% by weight based on the total amount of the carbon material; and the metal content is 30-60% by weight based on oxides.

3. The method according to claim 2, wherein: The amounts of the metal precursor and lignin used are such that, in the prepared carbon material, the carbon content is 45-67% by weight, based on the total amount of the carbon material; and the metal content is 33-55% by weight, calculated as oxide.

4. The method according to claim 1, wherein In the metal precursor, the molar ratio of copper to zinc is 1:(0.7-0.82) based on the elements.

5. The method according to claim 1, wherein The metal in the metal precursor further includes at least one of aluminum, manganese and nickel.

6. The method according to claim 5, wherein: Calculated as elements, the molar ratio of copper, aluminum, manganese and nickel is 1:(0-1):(0-1):(0-1).

7. The method according to claim 6, wherein: Calculated on an elemental basis, the molar ratio of copper, aluminum, manganese and nickel is 1:(0.1-0.5):(0.1-0.5):(0.1-0.5).

8. The method according to claim 1, wherein The solvent is water; and / or the lignin is alkali-washed lignin.

9. The method according to claim 1, wherein: In step (1), the contacting conditions include: carrying out under stirring conditions, a temperature of 15-35° C., and a time of 5-30 min.

10. The method according to claim 1, wherein In step (1), the contacting conditions include: stirring, a temperature of 20-30°C, and a time of 10-20 minutes.

11. The method according to claim 1, wherein The precipitant is at least one of sodium hydroxide, potassium hydroxide, sodium bicarbonate and potassium bicarbonate.

12. The method according to claim 1, wherein The precipitant is provided in the form of a solution.

13. The method according to claim 1, wherein The precipitation reaction conditions include: being carried out under stirring at a temperature of 15-35° C. and for 5-20 minutes.

14. The method according to claim 1, wherein The precipitation reaction conditions include: being carried out under stirring at a temperature of 20-30° C. and for 10-15 minutes.

15. The method according to claim 1, wherein The method further comprises performing suction filtration after the precipitation reaction to obtain the solid product.

16. The method according to claim 1, wherein In step (3), the calcination conditions include: a calcination temperature of 200-600°C; and a calcination time of 150-300 minutes.

17. The method according to claim 1, wherein In step (3), the calcination conditions include: a calcination temperature of 350-500°C; and a calcination time of 180-240 minutes.

18. The method according to claim 1, wherein In step (3), the calcination is carried out under an inert atmosphere, and the inert atmosphere is provided by at least one of nitrogen, argon, helium and neon.

19. The method according to claim 1, wherein In step (4), the metal base is selected from sodium hydroxide and / or potassium hydroxide.

20. The method according to claim 1, wherein In step (4), the mass ratio of the metal base to the lignin is 1.5-5:

1.

21. The method according to claim 20, wherein The mass ratio of the metal base to the lignin is 1-2:

1.

22. The method according to claim 1, wherein The carbonization conditions include: a carbonization temperature of 600-1200° C.; and a carbonization time of 100-270 minutes.

23. The method according to claim 22, wherein The carbonization conditions include: a carbonization temperature of 800-1000° C.; and a carbonization time of 120-240 minutes.

24. The method according to claim 1, wherein The carbonization is performed under an inert atmosphere provided by at least one of nitrogen, argon, helium and neon.

25. The method according to claim 1, wherein The method further comprises drying after the impregnation and then carbonizing, wherein the drying temperature is 40-100°C.

26. A carbon material for removing hydrogen sulfide obtained by the method according to any one of claims 1 to 25.

27. The carbon material according to claim 26, wherein In the pore size distribution curve of the carbon material, there are at least two mesopore distribution peaks.

28. The carbon material according to claim 27, wherein In the pore size distribution curve of the carbon material, there is a first mesopore distribution peak at 2.2-2.5 nm, and a second mesopore distribution peak at 4-4.5 nm.

29. The carbon material according to claim 26, wherein The specific surface area of ​​the carbon material is greater than 400 m 2 / g.

30. The carbon material according to claim 29, wherein The specific surface area of ​​the carbon material is greater than 600 m 2 / g.

31. The carbon material according to claim 30, wherein The specific surface area of ​​the carbon material is 650-1000m 2 / g.

32. Use of the carbon material for removing hydrogen sulfide according to any one of claims 26 to 31 in treating hydrogen sulfide in hydrogen.

Images