A catalyst for reforming methane and hydrogen sulfide to produce hydrogen, a preparation method thereof, and an application thereof

Abstract

The present invention discloses a methane hydrogen sulfide reforming hydrogen production catalyst and its preparation method and application, the catalyst includes a carrier, an active metal component and an auxiliary agent component, wherein the carrier is a rare earth element modified SBA-15 molecular sieve, the active metal is a VIB group metal, and the auxiliary agent is lithium, wherein the active metal and the auxiliary agent are distributed on the carrier in the form of oxides. The preparation method of the catalyst is to first dissolve the triblock copolymer P123 in water to adjust the pH value to obtain a stream A; then add a silicon precursor and a rare earth element precursor to fully mix and react, and after the reaction is completed, dry and roast to obtain a carrier; finally, the carrier is added to a mixed solution containing an active metal component precursor and an auxiliary agent precursor and impregnated, and after impregnation is completed, dried and roasted to obtain a catalyst. The catalyst provided by the present invention shows better thermal stability and higher reaction activity in the methane hydrogen sulfide hydrogen production process.

Description

Technical Field

[0001] The present invention belongs to the technical field of catalytic materials, and in particular relates to a methane reforming hydrogen production catalyst and a preparation method thereof. Background Art

[0002] The development and utilization of hydrogen energy has become an important way of global energy transformation and an important part of my country's strategy to become an energy power.

[0003] Currently, most of the world's hydrogen comes from the reforming of natural gas with water vapor. H2S, a major impurity in natural gas, not only corrodes gas pipelines but also poisons and deactivates reforming catalysts. On the other hand, the sulfur and hydrogen contained in H2S are extremely valuable resources for the production of sulfur and hydrogen. Traditional industry converts H2S into non-toxic and inexpensive sulfur and H2O through the Claus process. However, the hydrogen in the H2S is converted into wastewater and discharged, wasting hydrogen resources. Therefore, the treatment and effective utilization of natural gas containing hydrogen sulfide is an urgent issue that needs to be addressed.

[0004] As early as 1939, a patent proposed the production of CS2 by reacting CH4 with H2S. However, it wasn't until 1991 that Greek researcher Papayannako (International Association for Hydrogen Energy, 1991) first recognized the H2S and CH4 reforming reaction (H2SMR) as an effective hydrogen production route. Because this reaction is highly endothermic, it requires temperatures exceeding 800°C.

[0005] 2H2S+ CH4→ 4H2+CS2; =232.4 kJ / mol

[0006] The H2SMR process can produce high-value-added carbon disulfide as a by-product while producing hydrogen, making it a technology with great application prospects. As a new hydrogen production route, the current research on this process mainly focuses on kinetic and thermodynamic simulation calculations. Experimental research is also being carried out at home and abroad. The design and development of catalysts are crucial for the methane hydrogen sulfide reforming process. The difficulty in designing catalysts for this process lies in the fact that they must be resistant to high temperatures and H2S corrosion at the same time. Mexican researchers used Fe2O3 / γ-Al2O3 as a catalyst and investigated the reaction performance under conditions of an H2S / CH4 molar ratio of 12:1. They found that the initial H2S conversion rate was high, but it dropped rapidly after 4 hours. Martı´nez-Salazar et al. (International Journal of Hydrogen Energy. 2015) prepared Mo,Cr / ZrO2–La2O3 and Mo,Cr / ZrO2–SBA15 catalysts and found that the former exhibited higher reforming reaction activity, with an H2 yield of 64% in the temperature range of 1073K-1123K, while the latter formed a ZrSiO4 mixed phase with poor stability. Summary of the Invention

[0007] In order to solve the problems of poor dispersion performance, easy carbon deposition, poor thermal stability, and low raw material conversion rate in the current methane hydrogen sulfide reforming hydrogen production catalyst, the main purpose of the present invention is to provide a supported methane hydrogen sulfide reforming hydrogen production catalyst and its preparation method and application. The catalyst provided by the present invention exhibits better thermal stability and higher reaction activity in the methane hydrogen sulfide hydrogen production process.

[0008] In order to achieve the above-mentioned object of the invention, the first aspect of the present invention provides a methane hydrogen sulfide reforming hydrogen production catalyst, which includes a carrier, an active metal component and an auxiliary agent component, wherein the carrier is a rare earth element modified SBA-15 molecular sieve, the active metal is a VIB group metal, and the auxiliary agent is lithium, wherein the active metal and the auxiliary agent are distributed on the carrier in the form of oxides, and based on the weight of the catalyst, the content of the active metal component as oxide is 5 to 50 wt%, the content of the auxiliary agent as oxide is 0.1 to 10 wt%, and the content of the carrier is 40 to 90 wt%.

[0009] Furthermore, in the above-mentioned methane hydrogen sulfide reforming catalyst for hydrogen production, the carrier is preferably a cerium (Ce)-modified SBA-15 molecular sieve.

[0010] Furthermore, in the above-mentioned methane hydrogen sulfide reforming catalyst for hydrogen production, the active metal is preferably Mo.

[0011] Furthermore, in the above-mentioned methane hydrogen sulfide reforming hydrogen production catalyst, the specific surface area of the catalyst is 200 to 1500 m 2 / g, preferably 300 to 1000 m2 / g.

[0012] Furthermore, in the above-mentioned methane hydrogen sulfide reforming hydrogen production catalyst, the pore size distribution of the catalyst is 0.8 to 20 nm, preferably 1.0 to 10 nm.

[0013] A second aspect of the present invention provides a method for preparing a catalyst for hydrogen production by reforming methane with hydrogen sulfide, comprising the following steps:

[0014] (1) After dissolving the triblock copolymer P123 in water, an acidic solution was added dropwise to adjust the pH value to 2-4 to obtain a stream A;

[0015] (2) Under contact conditions, the silicon precursor, the rare earth element precursor, and the stream A obtained in step (1) are fully mixed and then subjected to a crystallization reaction. After the reaction is completed, the rare earth element-modified SBA-15 molecular sieve carrier is obtained by drying and calcining;

[0016] (3) The rare earth element-modified carrier obtained in step (2) is added to a mixed solution containing an active metal component precursor and an auxiliary agent precursor for impregnation. After impregnation, the catalyst is obtained after drying and calcination.

[0017] Furthermore, in the above-mentioned preparation method of the catalyst for hydrogen production by reforming methane hydrogen sulfide, the acidic solution described in step (1) is an inorganic acid. Specifically, the acidic solution can be at least one of hydrochloric acid, nitric acid, and sulfuric acid, preferably hydrochloric acid. Furthermore, the mass concentration of the acidic solution is 10 to 40 wt%.

[0018] Furthermore, in the above-mentioned method for preparing the catalyst for hydrogen production by reforming methane hydrogen sulfide, the silicon precursor in step (2) is selected from one or more of tetraethyl orthosilicate (TEOS), sodium silicate, silica sol, etc., preferably tetraethyl orthosilicate.

[0019] Furthermore, in the above-mentioned method for preparing the catalyst for hydrogen production by reforming methane hydrogen sulfide, the rare earth element precursor described in step (2) is a water-soluble inorganic acid salt containing a rare earth element, specifically at least one of a nitrate containing a rare earth element, a sulfate containing a rare earth element, and a chloride containing a rare earth element. The rare earth element is preferably La and / or Ce, and more preferably Ce; the rare earth element precursor is preferably cerium nitrate and / or cerium chloride.

[0020] Furthermore, in the preparation method of the above-mentioned methane hydrogen sulfide reforming hydrogen production catalyst, the molar ratio of the rare earth element precursor (calculated as element), the silicon precursor (calculated as Si element), and the triblock copolymer (P123) is 1:2~200:0.1~10.

[0021] Furthermore, in the above-mentioned method for preparing the catalyst for hydrogen production by reforming methane sulfide, the temperature for mixing the silicon precursor, the rare earth element precursor, and the stream A obtained in step (1) in step (2) is 20 to 100° C., preferably 40 to 60° C., and the mixing time is 12 to 36 hours, preferably 15 to 25 hours.

[0022] Furthermore, in the preparation method of the above-mentioned supported methane hydrogen sulfide reforming catalyst for hydrogen production, the crystallization reaction temperature in step (2) is 80-150°C, preferably 90-120°C, and the reaction time is 24-60h, preferably 36-50h.

[0023] Furthermore, in the above-mentioned preparation method of the methane hydrogen sulfide reforming hydrogen production catalyst, the drying conditions in step (2) are: drying temperature is 50 to 200° C., preferably 80 to 120° C.; and drying time is 1 to 24 hours, preferably 4 to 12 hours.

[0024] Furthermore, in the above-mentioned preparation method of the methane hydrogen sulfide reforming hydrogen production catalyst, the calcination conditions in step (2) are: the calcination temperature is 200-1000°C, preferably 400-800°C; the calcination time is 1-24h, preferably 4-8h.

[0025] Furthermore, in the above-mentioned preparation method of the methane hydrogen sulfide reforming hydrogen production catalyst, the active metal component precursor in step (3) is an inorganic acid salt containing an active metal, specifically at least one of ammonium heptamolybdate, ammonium tetrathiomolybdate, etc.

[0026] Furthermore, in the above-mentioned method for preparing the catalyst for hydrogen production by reforming methane hydrogen sulfide, the auxiliary agent precursor in step (3) is at least one of lithium nitrate and lithium chloride.

[0027] Furthermore, in the above-mentioned preparation method of the methane hydrogen sulfide reforming hydrogen production catalyst, the drying conditions in step (3) are: drying temperature is 50 to 200° C., preferably 80 to 120° C.; and drying time is 1 to 24 hours, preferably 4 to 12 hours.

[0028] Furthermore, in the above-mentioned preparation method of the catalyst for hydrogen production by reforming methane sulfide, the calcination conditions in step (3) are as follows: the calcination temperature is 200-1000°C, preferably 400-800°C; and the calcination time is 1-24h, preferably 4-8h.

[0029] Furthermore, in the preparation method of the above-mentioned methane hydrogen sulfide reforming hydrogen production catalyst, based on the weight of the catalyst, the content of the active metal component as oxide is 5-50wt%, the content of the auxiliary agent as oxide is 0.1-10wt%, and the content of the carrier is 40-90wt%.

[0030] A third aspect of the present invention provides a catalyst for hydrogen production by reforming methane and hydrogen sulfide obtained by the above-mentioned preparation method.

[0031] A fourth aspect of the present invention provides a methane hydrogen sulfide reforming hydrogen production process, wherein raw materials methane and hydrogen sulfide enter a reactor, and the reactor is filled with the above-mentioned methane hydrogen sulfide reforming hydrogen production catalyst or the methane hydrogen sulfide reforming hydrogen production catalyst obtained by the above-mentioned preparation method.

[0032] Furthermore, in the above-mentioned methane hydrogen sulfide reforming hydrogen production process, the methane hydrogen sulfide reforming hydrogen production catalyst needs to be sulfided before use. The sulfidation can adopt any of the existing catalyst sulfidation methods, such as introducing hydrogen sulfide at a temperature of 100-800°C for 0.5-10h.

[0033] Furthermore, in the above-mentioned methane-hydrogen sulfide reforming hydrogen production process, the volume ratio of methane to hydrogen sulfide is 1:0.25-10.

[0034] Furthermore, in the above methane hydrogen sulfide reforming hydrogen production process, the reaction temperature is 600-1000°C, the reaction pressure is preferably 0.1MPa-5MPa, preferably 0.1MPa-3MPa; the volume space velocity is 100h -1 ~3000h -1 , preferably 300h -1 ~2000h -1 .

[0035] Compared with the prior art, the methane hydrogen sulfide reforming catalyst for hydrogen production provided by the present invention, its preparation method and application have the following technical effects:

[0036] 1. The present invention provides a novel supported catalyst for hydrogen production by reforming methane to hydrogen sulfide. The catalyst utilizes an SBA-15 molecular sieve in situ modified with rare earth elements as a support. The catalyst exhibits high specific surface area and excellent thermal stability. The active metal component, a Group VIB metal, exhibits high methane and hydrogen sulfide decomposition performance, along with excellent high-temperature and sulfur tolerance, resulting in a high feedstock conversion rate during the methane to hydrogen sulfide reforming reaction. The introduction of rare earth elements (particularly cerium) improves the catalyst's thermal stability and the subsequent dispersion of the active metal components on the support. Furthermore, the introduced rare earth element, Ce, interacts with the active metal component, Mo, enhancing the catalyst's catalytic activity.

[0037] 2. In the methane hydrogen sulfide reforming hydrogen production catalyst and its preparation method of the present invention, by introducing an additive, the presence of its alkalinity can reduce carbon deposition on the catalyst surface and improve the conversion rate of hydrogen sulfide. DETAILED DESCRIPTION

[0038] The catalyst of the present invention, its preparation method and application are further illustrated below by way of examples, but the present invention should not be considered to be limited to the following examples.

[0039] Unless expressly stated otherwise, throughout the specification and claims, the term “comprise” or variations such as “include” or “comprising” will be understood to include the stated elements or components but not to exclude other elements or components.

[0040] The experimental methods in the following examples and comparative examples, unless otherwise specified, are all conventional methods in the art. The experimental materials used in the following examples, unless otherwise specified, were purchased from conventional biochemical reagent stores.

[0041] The analysis method of the present invention: the specific surface area and pore distribution are measured by low-temperature liquid nitrogen physical adsorption method.

[0042] In the present invention, the calculation formula of CH4 conversion rate is as follows: CH4 = ×100%; where A CH4,in is the chromatographic peak area of methane at the reactor inlet, A CH4,out is the chromatographic peak area of methane at the reactor outlet.

[0043] Example 1

[0044] 14.2g of P123 was weighed and dissolved in water. 35wt% hydrochloric acid solution was added dropwise to adjust the pH to 3.2. 127.3g of tetraethyl orthosilicate and 4.0g of cerium nitrate were added, and the mixture was stirred in a 40°C waterbath for 18 hours. The mixture was then placed in a reactor and reacted in a 100°C oven for 36 hours. The mixture was removed, filtered, washed until neutral, and oven-dried at 100°C for 24 hours. The mixture was then calcined in a muffle furnace at 600°C for 4 hours to obtain a Ce-SBA-15 support. 10.0g of Ce-SBA-15 molecular sieve was impregnated in a mixed solution of ammonium heptamolybdate and lithium chloride, dried at 110°C for 8 hours, and calcined at 800°C for 4 hours. The resulting catalyst, based on the weight of the oxides, consisted of 20.2wt% molybdenum oxide, 2.0wt% lithium oxide, and the remainder as support. Catalyst properties are shown in Table 1.

[0045] The catalyst was applied to the methane hydrogen sulfide reforming reaction to produce hydrogen. First, hydrogen sulfide was introduced at 250 ° C for 8 hours for pre-sulfurization. Then, the raw gas H2S:CH4 was introduced at a ratio of 4:1. At a space velocity of 800 h -1 , 0.1MPa, and the reaction was carried out at a high temperature of 800℃. The CH4 conversion rate reached 48.6%, and the conversion rate remained at 42.2% after 300h.

[0046] Example 2

[0047] 350.7g of P123 was weighed and dissolved in water. 35wt% hydrochloric acid solution was added dropwise to adjust the pH to 3.2. 400.2g of tetraethyl orthosilicate and 4.0g of cerium nitrate were added, and the mixture was stirred in a 40°C waterbath for 18 hours. The mixture was then placed in a reactor and reacted in a 110°C oven for 36 hours. The mixture was removed, filtered, washed until neutral, and oven-dried at 100°C for 12 hours. The mixture was then calcined in a muffle furnace at 550°C for 4 hours to obtain a Ce-SBA-15 support. 10.0g of Ce-SBA-15 molecular sieve was impregnated in a mixed solution of ammonium heptamolybdate and lithium chloride, dried at 110°C for 8 hours, and calcined at 800°C for 4 hours. The resulting catalyst, based on the weight of the oxides, consisted of 25.5wt% molybdenum oxide, 2.3wt% lithium oxide, and the remainder as support. Catalyst properties are shown in Table 1.

[0048] The catalyst was applied to the methane hydrogen sulfide reforming reaction to produce hydrogen. First, hydrogen sulfide was introduced at 250 ° C for 8 hours for pre-sulfurization. Then, the raw gas H2S:CH4 was introduced at a ratio of 4:1. At a space velocity of 800 h -1 , 0.1MPa, and a high temperature of 800℃, the CH4 conversion rate reached 53.6%, and the conversion rate remained at 50.2% after 300h.

[0049] Example 3

[0050] 13.2g of P123 was weighed and dissolved in water. 35wt% hydrochloric acid solution was added dropwise to adjust the pH to 3.2. 7.5g of silica sol and 4g of cerium chloride were added, and the mixture was stirred in a 40°C water bath for 15 hours. The mixture was then placed in a reactor and reacted in a 110°C oven for 38 hours. The mixture was removed, filtered, washed until neutral, and oven-dried at 100°C for 12 hours. The mixture was then calcined in a muffle furnace at 550°C for 6 hours to obtain the Ce-SBA-15 support. 10.0g of Ce-SBA-15 molecular sieve was impregnated in a mixture of ammonium heptamolybdate and lithium chloride, dried at 110°C for 8 hours, and calcined at 850°C for 6 hours. The resulting catalyst, based on the weight of the oxides, consisted of 45.3wt% molybdenum oxide, 0.8wt% lithium oxide, and the remainder as support. Catalyst properties are shown in Table 1.

[0051] The catalyst was applied to the methane hydrogen sulfide reforming reaction to produce hydrogen. First, hydrogen sulfide was introduced at 250 ° C for 8 hours for pre-sulfurization. Then, the raw gas H2S:CH4 was introduced at a ratio of 4:1. At a space velocity of 800 h -1 , 0.1MPa, and the reaction was carried out at a high temperature of 800℃. The CH4 conversion rate reached 58.6%, and the conversion rate remained at 53.2% after 300h.

[0052] Example 4

[0053] 35.5g of P123 was weighed and dissolved in water. 36wt% sulfuric acid solution was added dropwise to adjust the pH to 3.2. 25.5g of tetraethyl orthosilicate and 4.0g of cerium nitrate were added, and the mixture was stirred in a 40°C waterbath for 18 hours. The mixture was then placed in a reactor and reacted in a 110°C oven for 36 hours. The mixture was removed, filtered, washed until neutral, and oven-dried at 100°C for 12 hours. The mixture was then calcined in a muffle furnace at 550°C for 4 hours to obtain a Ce-SBA-15 support. 10.0g of Ce-SBA-15 molecular sieve was impregnated in a mixed solution of ammonium molybdate and lithium nitrate, dried at 110°C for 8 hours, and calcined at 800°C for 4 hours. The resulting catalyst, based on the weight of the oxides, consisted of 30.2wt% molybdenum oxide, 3.5wt% lithium oxide, and the remainder as support. Catalyst properties are shown in Table 1.

[0054] The catalyst was applied to the methane hydrogen sulfide reforming reaction to produce hydrogen. First, hydrogen sulfide was introduced at 250 ° C for 68 hours for pre-sulfurization. Then, the raw gas H2S:CH4 was introduced at a ratio of 4:1. At a space velocity of 1000 h -1 , 0.1MPa, and a high temperature of 800℃, the CH4 conversion rate reached 52.3%, and the conversion rate remained at 50.1% after 300h.

[0055] Example 5

[0056] 17.6g of P123 was weighed and dissolved in water. 35wt% hydrochloric acid solution was added dropwise to adjust the pH to 3.4. 25.0g of tetraethyl orthosilicate and 2.0g of lanthanum nitrate were added, and the mixture was stirred in a 40°C water bath for 20 hours. The mixture was then placed in a reactor and reacted in a 110°C oven for 36 hours. The mixture was removed, filtered, washed until neutral, and oven-dried at 100°C for 12 hours. The mixture was then calcined in a muffle furnace at 550°C for 4 hours to obtain a La-SBA-15 support. 10.0g of Ce-SBA-15 molecular sieve was impregnated in a mixed solution of ammonium heptamolybdate and lithium chloride, dried at 110°C for 8 hours, and calcined at 800°C for 4 hours. The resulting catalyst, based on the weight of the oxides, consisted of 6.8wt% molybdenum oxide, 8.8wt% lithium oxide, and the remainder as support. Catalyst properties are shown in Table 1.

[0057] The catalyst was applied to the methane hydrogen sulfide reforming reaction to produce hydrogen. First, hydrogen sulfide was introduced at 250 ° C for 8 hours for pre-sulfurization. Then, the raw gas H2S:CH4 was introduced at a ratio of 4:1. At a space velocity of 800 h -1 , 0.1MPa, and the reaction was carried out at a high temperature of 800℃. The CH4 conversion rate reached 43.6%, and the conversion rate remained at 40.5% after 300h.

[0058] Example 6

[0059] 53.3g of P123 was weighed and dissolved in water. 36wt% hydrochloric acid solution was added dropwise to adjust the pH to 3.4. 95.7g of tetraethyl orthosilicate and 3.0g of cerium nitrate were added, and the mixture was stirred in a 50°C waterbath for 18 hours. The mixture was then placed in a reactor and reacted in a 110°C oven for 48 hours. The mixture was removed, filtered, washed until neutral, and oven-dried at 120°C for 12 hours. The mixture was then calcined in a muffle furnace at 600°C for 4 hours to obtain the Ce-SBA-15 support. 10.0g of Ce-SBA-15 molecular sieve was impregnated in a mixed solution of ammonium molybdate and potassium nitrate, dried at 110°C for 8 hours, and calcined at 800°C for 6 hours. The resulting catalyst, based on the weight of the oxides, consisted of 24.6wt% molybdenum oxide, 3.1wt% potassium oxide, and the remainder as support. Catalyst properties are shown in Table 1.

[0060] The catalyst was applied to the methane hydrogen sulfide reforming reaction to produce hydrogen. First, hydrogen sulfide was introduced at 250 ° C for 6 hours for pre-sulfurization. Then, the raw gas H2S:CH4 was introduced at a ratio of 4:1. At a space velocity of 800 h -1 , 1.0MPa, and the reaction was carried out at a high temperature of 800℃. The CH4 conversion rate reached 50.3%, and the conversion rate remained at 43.8% after 300h.

[0061] Example 7

[0062] 26.6g of P123 was weighed and dissolved in water. 35wt% hydrochloric acid solution was added dropwise to adjust the pH to 3.4. 57.3g of tetraethyl orthosilicate and 2.0g of cerium nitrate were added, and the mixture was stirred in a 40°C water bath for 18 hours. The mixture was then placed in a reactor and reacted in a 110°C oven for 36 hours. The mixture was removed, filtered, washed until neutral, and oven-dried at 100°C for 12 hours. The mixture was then calcined in a muffle furnace at 550°C for 4 hours to obtain the Ce-SBA-15 support. 10.0g of Ce-SBA-15 molecular sieve was impregnated in a mixed solution of ammonium heptamolybdate and lithium chloride, dried at 110°C for 8 hours, and calcined at 800°C for 4 hours. The resulting catalyst, based on the weight of the oxides, consisted of 27.5wt% molybdenum oxide, 3.6wt% lithium oxide, and the remainder as support. Catalyst properties are shown in Table 1.

[0063] The catalyst was applied to the methane hydrogen sulfide reforming reaction to produce hydrogen. First, hydrogen sulfide was introduced at 300 ° C for 7 hours for pre-sulfurization. Then, the raw gas H2S:CH4 was introduced in a ratio of 4:1. At a space velocity of 800 h -1 , 0.3MPa, and a high temperature of 800℃, the CH4 conversion rate reached 50.7%, and the conversion rate remained at 43.6% after 300h.

[0064] Example 8

[0065] 17.6g of P123 was weighed and dissolved in water. 35wt% hydrochloric acid solution was added dropwise to adjust the pH to 3.4. 25.0g of tetraethyl orthosilicate and 2.0g of cerium nitrate were added, and the mixture was stirred in a 40°C waterbath for 18 hours. The mixture was then placed in a reactor and reacted in a 110°C oven for 36 hours. The mixture was removed, filtered, washed until neutral, and oven-dried at 100°C for 12 hours. The mixture was then calcined in a muffle furnace at 550°C for 6 hours to obtain the Ce-SBA-15 support. 10.0g of Ce-SBA-15 molecular sieve was impregnated in a mixed solution of ammonium molybdate and lithium chloride, dried at 110°C for 8 hours, and calcined at 880°C for 8 hours. The resulting catalyst, based on the weight of the oxides, consisted of 26.2wt% molybdenum oxide, 4.6wt% lithium oxide, and the remainder as support. Catalyst properties are shown in Table 1.

[0066] The catalyst was applied to the methane hydrogen sulfide reforming reaction to produce hydrogen. First, hydrogen sulfide was introduced at 250 ° C for 6 hours for pre-sulfurization. Then, the raw gas H2S:CH4 was introduced at a ratio of 4:1. At a space velocity of 800 h -1 , 1.0MPa, and the reaction was carried out at a high temperature of 900℃. The CH4 conversion rate reached 63.6%, and the conversion rate remained at 60.8% after 300h.

[0067] Comparative Example 1

[0068] The reaction was essentially the same as Example 1, except that Ce-modified SBA-15 molecular sieve was not used. The single-pass conversion rate of CH4 reached 40.6%, but after 300 h, the conversion rate dropped to 22.2%.

[0069] Comparative Example 2

[0070] The reaction was essentially the same as Example 1, except that no auxiliary agent was used. The single-pass conversion rate of CH4 reached 32.1%, and after 300 h, the conversion rate dropped to 15.3%.

[0071] Comparative Example 3

[0072] Compared with Example 2, the support was not modified with Ce and no alkali metal oxide was used. The single-pass conversion rate of CH4 reached 25.6%, and the conversion rate dropped to 8.3% after 300 h.

[0073] Table 1 Catalyst properties

[0074]

Claims

1. A catalyst for hydrogen production by reforming methane with hydrogen sulfide, comprising a carrier, an active metal component and a promoter component, wherein: The carrier is cerium-modified SBA-15 molecular sieve, the active metal is Mo, and the auxiliary agent is lithium. The active metal and the auxiliary agent are distributed on the carrier in the form of oxides. Based on the weight of the catalyst, the content of the active metal component in terms of oxide is 5-50wt%, the content of the auxiliary agent in terms of oxide is 0.1-10wt%, and the carrier content is 40-90wt%. The specific surface area of the catalyst is 200-1500m 2 / g; the pore size distribution of the catalyst is 0.8~20nm.

2. The catalyst for hydrogen production from methane sulfide reforming according to claim 1, characterized in that: The specific surface area of the catalyst is 300 to 1000 m 2 / g.

3. The catalyst for hydrogen production from methane sulfide reforming according to claim 1, characterized in that: The pore size distribution of the catalyst is 1.0 to 10 nm.

4. The method for preparing the catalyst for hydrogen production by reforming methane with hydrogen sulfide according to any one of claims 1 to 3, comprising the following steps: (1) After dissolving the triblock copolymer P123 in water, an acidic solution was added dropwise to adjust the pH value to 2-4 to obtain a stream A; (2) Under contact conditions, the silicon precursor, the rare earth element precursor, and the stream A obtained in step (1) are fully mixed and then subjected to a crystallization reaction. After the reaction is completed, the rare earth element-modified SBA-15 molecular sieve carrier is obtained by drying and calcining; (3) The rare earth element-modified carrier obtained in step (2) is added to a mixed solution containing an active metal component precursor and an auxiliary agent precursor for impregnation. After impregnation, the catalyst is obtained after drying and calcination; the active metal component precursor is ammonium heptamolybdate and / or ammonium tetrathiomolybdate.

5. The method for preparing a catalyst for hydrogen production by reforming methane with hydrogen sulfide according to claim 4, wherein: The acidic solution described in step (1) is an inorganic acid, which is at least one of hydrochloric acid, nitric acid, and sulfuric acid, and the mass concentration of the acidic solution is 10 to 40 wt%.

6. The method for preparing the catalyst for hydrogen production by reforming methane hydrogen sulfide according to claim 5, characterized in that: The acidic solution is hydrochloric acid.

7. The method for preparing a catalyst for hydrogen production by reforming methane with hydrogen sulfide according to claim 4, wherein: The silicon precursor described in step (2) is selected from one or more of ethyl orthosilicate, sodium silicate, and silica sol.

8. The method for preparing a catalyst for hydrogen production by reforming methane with hydrogen sulfide according to claim 4, wherein: The silicon precursor described in step (2) is ethyl orthosilicate.

9. The method for preparing a catalyst for hydrogen production by reforming methane with hydrogen sulfide according to claim 4, wherein: The rare earth element precursor described in step (2) is a water-soluble inorganic acid salt containing a rare earth element.

10. The method for preparing a catalyst for hydrogen production by reforming methane with hydrogen sulfide according to claim 4 or 9, characterized in that: The rare earth element precursor described in step (2) is at least one of a nitrate containing a rare earth element, a sulfate containing a rare earth element, and a chloride containing a rare earth element, and the rare earth element is Ce.

11. The method for preparing a catalyst for hydrogen production by reforming methane with hydrogen sulfide according to claim 10, characterized in that: The rare earth element precursor in step (2) is cerium nitrate and / or cerium chloride.

12. The method for preparing a catalyst for hydrogen production by reforming methane with hydrogen sulfide according to claim 4, wherein: The molar ratio of the rare earth element precursor, calculated as the element, the silicon precursor, and the triblock copolymer P123 is 1:2-200:0.1-10.

13. The method for preparing a catalyst for hydrogen production by reforming methane with hydrogen sulfide according to claim 4, characterized in that: In step (2), the silicon precursor, the rare earth element precursor, and the material stream A obtained in step (1) are mixed at a temperature of 20 to 100° C., and the mixing time is 12 to 36 hours.

14. The method for preparing a catalyst for hydrogen production by reforming methane with hydrogen sulfide according to claim 4, wherein: In step (2), the silicon precursor, the rare earth element precursor, and the material stream A obtained in step (1) are mixed at a temperature of 40 to 60° C., and the mixing time is 15 to 25 hours.

15. The method for preparing a catalyst for hydrogen production by reforming methane with hydrogen sulfide according to claim 4, characterized in that: In step (2), the crystallization reaction temperature is 80-150° C., and the reaction time is 24-60 h.

16. The method for preparing a catalyst for hydrogen production by reforming methane with hydrogen sulfide according to claim 4, characterized in that: In step (2), the crystallization reaction temperature is 90-120° C., and the reaction time is 36-50 h.

17. The method for preparing a catalyst for hydrogen production by reforming methane with hydrogen sulfide according to claim 4, characterized in that: The drying conditions in step (2) are: drying temperature of 50 to 200° C.; drying time of 1 to 24 hours.

18. The method for preparing a catalyst for hydrogen production by reforming methane with hydrogen sulfide according to claim 4, characterized in that: The drying conditions in step (2) are: drying temperature of 80 to 120° C.; drying time of 4 to 12 hours.

19. The method for preparing a catalyst for hydrogen production by reforming methane with hydrogen sulfide according to claim 4, characterized in that: The roasting conditions in step (2) are: roasting temperature of 200-1000° C.; roasting time of 1-24 h.

20. The method for preparing a catalyst for hydrogen production by reforming methane with hydrogen sulfide according to claim 4, characterized in that: The calcination conditions in step (2) are: calcination temperature of 400-800° C.; calcination time of 4-8 h.

21. The method for preparing a catalyst for hydrogen production by reforming methane with hydrogen sulfide according to claim 4, characterized in that: In step (3), the auxiliary agent precursor is at least one of lithium nitrate and lithium chloride.

22. The method for preparing a catalyst for hydrogen production by reforming methane with hydrogen sulfide according to claim 4, characterized in that: The drying conditions in step (3) are: drying temperature of 50 to 200° C.; drying time of 1 to 24 hours.

23. The method for preparing a catalyst for hydrogen production by reforming methane hydrogen sulfide according to claim 4, characterized in that: The drying conditions in step (3) are: drying temperature of 80 to 120° C.; drying time of 4 to 12 hours.

24. The method for preparing a catalyst for hydrogen production by reforming methane with hydrogen sulfide according to claim 4, characterized in that: The roasting conditions in step (3) are: roasting temperature of 200 to 1000° C.; roasting time of 1 to 24 hours.

25. The method for preparing a catalyst for hydrogen production by reforming methane with hydrogen sulfide according to claim 4, characterized in that: The calcination conditions in step (3) are: calcination temperature of 400-800°C; calcination time of 4-8h.

26. The method for preparing a catalyst for hydrogen production by reforming methane hydrogen sulfide according to claim 4, characterized in that: Based on the weight of the catalyst, the content of the active metal component in terms of oxide is 5-50wt%, the content of the auxiliary agent in terms of oxide is 0.1-10wt%, and the content of the carrier is 40-90wt%.

27. A process for producing hydrogen through reforming methane and hydrogen sulfide, wherein raw materials methane and hydrogen sulfide enter a reactor, and the reactor is filled with the methane and hydrogen sulfide reforming catalyst for producing hydrogen according to any one of claims 1 to 3 or the methane and hydrogen sulfide reforming catalyst obtained by the preparation method according to any one of claims 4 to 26.

28. The process for producing hydrogen by reforming methane hydrogen sulfide according to claim 27, characterized in that: The methane hydrogen sulfide reforming catalyst for hydrogen production is subjected to sulfidation treatment before use.

29. The process for producing hydrogen by reforming methane hydrogen sulfide according to claim 27, characterized in that: The volume ratio of methane to hydrogen sulfide is 1:0.25~10.

30. The process for producing hydrogen by reforming methane hydrogen sulfide according to claim 27, characterized in that: The reaction temperature is 600-1000℃, the reaction pressure is 0.1MPa-5MPa, and the volume space velocity is 100h -1 ~3000h -1 .

31. The process for producing hydrogen by reforming methane hydrogen sulfide according to claim 27, characterized in that: The reaction temperature is 600-1000°C, the reaction pressure is 0.1MPa-3MPa, and the volume space velocity is 300h -1 ~2000h -1 .

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