Process for the preparation of a high temperature shift catalyst with shortened sulphurization time

Abstract

The application belongs to the technical field of catalyst preparation, and particularly relates to a preparation method of a high-temperature shift catalyst with shortened sulfur loading time. The preparation method of the high-temperature shift catalyst with shortened sulfur loading time comprises the following steps: preparing raw materials of the high-temperature shift catalyst into a solution, carrying out a co-precipitation reaction and washing, then putting the filter cake into a reaction kettle, adding deionized water to stir and pulp, then carrying out ultrasonic oscillation, adding a calcium nitrate solution, after the reaction is completed, transferring the material to a washing device, washing for 3-5 times, and after post-treatment, the high-temperature shift catalyst with shortened sulfur loading time is prepared. The application provides the preparation method of the high-temperature shift catalyst with shortened sulfur loading time, and the catalyst prepared by the method has significantly shortened sulfur loading time in the reduction process.

Description

Technical Field

[0001] This invention belongs to the field of catalyst preparation technology, specifically relating to a method for preparing a high-temperature shift catalyst that shortens sulfur release time. Background Technology

[0002] Shift reactions mainly occur in hydrogen production and ammonia synthesis. In hydrogen production units, the purpose of the CO shift reaction is primarily to enrich hydrogen production and reduce CO content, thus meeting the requirements of the subsequent PSA adsorbent for crude hydrogen composition. In ammonia synthesis units, the CO shift section is located downstream of the ammonia plant in the secondary reforming stage, and its main purpose is to increase hydrogen production and reduce the CO content in the syngas.

[0003] Traditional high-temperature (medium-temperature) shift catalysts are iron-chromium based, with Fe2O3 as the active component and Cr2O3 as an additive. High-temperature shift catalysts are mainly prepared from FeSO4·7H2O. During precipitation and washing, trace amounts of FeSO4 become trapped within the precipitate particles and cannot be completely removed. Another type of high-temperature shift catalyst is prepared using chromium oxide as the raw material, and a small amount of Na2SO4 (or K2SO4) is introduced during the preparation process, resulting in the presence of certain sulfides in the finished catalyst. During and after reduction in application, trace amounts of sulfides in the high-temperature shift catalyst escape as H2S. To protect subsequent processes, the high-temperature shift catalyst must complete the desulfurization process before normal use. The duration of desulfurization by the high-temperature shift catalyst will affect the venting volume of the feed gas, the operating time, and the production schedule.

[0004] To shorten the sulfur release time, those skilled in the art have adopted various methods, such as using the nitric acid method instead of the sulfuric acid method; directly using iron and chromium oxides as raw materials for dry mixing and ball milling; and improving washing methods to reduce the sulfur content of the catalyst.

[0005] CN101385977 discloses a method for preparing the catalyst by mixing iron and chromium oxides in a ratio of 90%–96% by weight of iron oxide (Fe₂O₃) and 2%–8% by weight of chromium oxide (Cr₂O₃), placing the mixture in a ball mill jar, ball milling for 1–25 hours, removing the powder, and then subjecting it to calcination, tableting, and granulation. The granulated catalyst is then impregnated at room temperature in an aqueous solution containing 0.5%–2% by weight of K₂O, and finally dried to obtain the catalyst of this invention. The ball milling method utilizes readily available raw materials, is simple in process, and the entire process is clean.

[0006] CN107649142B discloses a low-density iron-chromium CO conversion catalyst, which uses a mixture of Fe2O3, Cr2O3, CuO, and MxOY as raw materials. The precipitated catalyst is washed with a washing salt solution, which can effectively reduce the bulk sulfur content in the catalyst and improve the catalyst activity.

[0007] CN1173780C discloses a novel iron-based chromium-free carbon monoxide high-temperature shift catalyst and its preparation method. The method employs a combination of co-precipitation and wet mixing processes, using multiple metal oxide additives to synergistically replace chromium oxide. The iron-based chromium-free high-temperature shift catalyst developed in this invention completely eliminates chromium toxicity and does not introduce new toxic substances. It features low density and high strength, and its activity is superior to traditional iron-chromium high-temperature shift catalysts.

[0008] The aforementioned technologies can reduce the sulfur content of the catalyst to a certain extent, thereby shortening the sulfur release time. However, dissolving iron oxide with nitric acid releases a large amount of nitrogen oxides, which contradicts environmental protection principles; the steel from which iron oxide is derived also contains a small amount of sulfur; the process of directly dry-mixing raw materials to prepare the catalyst generates a lot of dust, which is seriously harmful to human health; the role of the additives cannot be fully utilized; and the bulk density of the finished catalyst is too high, which does not conform to the current trend of low bulk density catalysts; the washing salt solution contains a large amount of sodium nitrate, sodium carbonate, sodium bicarbonate, sodium hydroxide, ammonium bicarbonate, ammonium nitrate, ammonia, etc., which is environmentally unfriendly and requires subsequent wastewater treatment. Summary of the Invention

[0009] The technical problem to be solved by the present invention is to provide a method for preparing a high-temperature shift catalyst that shortens the sulfur release time. The catalyst prepared by this method significantly shortens the sulfur release time during the reduction process.

[0010] The method for preparing a high-temperature shift catalyst with shortened sulfur release time according to the present invention involves preparing the high-temperature shift catalyst raw material into a solution, performing a co-precipitation reaction and washing, placing the filter cake into a reaction vessel, adding deionized water and stirring to form a slurry, then subjecting it to ultrasonic vibration, adding calcium nitrate solution, and after the reaction is completed, transferring the material to a washing device and washing it 3-5 times. After post-treatment, a high-temperature shift catalyst with short sulfur release time is obtained.

[0011] The ultrasonic frequency is 25-40KHz.

[0012] The concentration of calcium nitrate solution is 0.1-2.0 mol / L.

[0013] The amount of calcium nitrate added is 1.3-1.8 times the theoretical sulfur content in the high-temperature shift catalyst body.

[0014] Post-processing includes: filtering / pressing the washed filter cake, drying, ball milling and granulation, calcining, adding graphite and deionized water to form tablets to obtain the finished catalyst.

[0015] Preferred preparation method one, preparation method of high temperature shift catalyst with shortened sulfur release time: Ammonium bicarbonate is prepared into a solution, ammonia is added to adjust to ammonium solution, ferrous sulfate solution is prepared, ferrous sulfate solution and ammonium solution are co-precipitated in a reactor, the precipitate is aged, filtered / pressed and washed, the filter cake is put into the reactor, deionized water is added and stirred and slurry is made, auxiliary agent is added during slurry making, and then ultrasonic vibration is performed, calcium nitrate solution is added, after the reaction is completed, the material is transferred to washing equipment for filtration / pressing and washing 3-5 times, the obtained filter cake is dried, potassium hydroxide solution is added, ball milling and granulation are performed, calcination is performed, graphite and deionized water are added and pelletized to obtain high temperature shift catalyst with short sulfur release time.

[0016] Preferred preparation method two, preparation method of high temperature shift catalyst with shortened sulfur release time: Ferrous sulfate, copper sulfate, chromium anhydride and auxiliary salt are prepared into a mixed solution, and co-precipitated with a precipitant. After the reaction is completed, an oxidant is added for oxidation aging treatment. After the precipitate is filtered / pressed and washed, the filter cake is put into a reaction vessel, deionized water is added and stirred to make a slurry, and then ultrasonic vibration is performed. Calcium nitrate solution is added. After the reaction is completed, the material is transferred to a washing device and washed 3-5 times. After the filter cake is dried, it is ball-milled and granulated. After calcination, graphite and deionized water are added and the mixture is granulated to obtain a high temperature shift catalyst with short sulfur release time.

[0017] The preferred preparation method three is a method for preparing a high-temperature shift catalyst with shortened sulfur release time: Ferrous sulfate, manganese sulfate, and nickel sulfate are dissolved in water to prepare a mixed solution. Under stirring and air introduction, the mixed solution undergoes a co-precipitation reaction with a precipitant solution. Under stirring and air introduction, the crystal form transformation of the ferric hydroxide precipitate is completed. After the precipitate is filtered / pressed and washed, the filter cake is placed in a reaction vessel, deionized water is added and stirred to form a slurry, followed by ultrasonic vibration. Calcium nitrate solution is added. After the reaction is completed, the material is transferred to a washing device and washed 3-5 times. After the filter cake is dried, copper nitrate and potassium hydroxide solution are added, and the mixture is ball-milled and granulated. After calcination, graphite and deionized water are added to form flakes, thus obtaining a high-temperature shift catalyst with a short sulfur release time.

[0018] Preferred preparation method four, preparation method of high temperature shift catalyst with shortened sulfur release time: Ferrous sulfate, chromic anhydride, and copper nitrate are dissolved in water to form a solution, which is then co-precipitated with a precipitant. After the reaction, the solution is kept at a constant temperature for aging. After aging, the solution is washed by vacuum filtration / pressure filtration with hot deionized water. The filter cake is then placed in a reaction vessel, deionized water is added, and the mixture is stirred and slurried. Then, ultrasonic vibration is performed, and calcium nitrate solution is added. The material is transferred to a washing device and washed 3-5 times. The resulting filter cake is dried and calcined to obtain a catalyst semi-finished product. Graphite and deionized water are added, and the mixture is ball-milled and granulated, then formed into sheets to obtain a high temperature shift catalyst with short sulfur release time.

[0019] The preparation method of the high-temperature shift catalyst for shortening sulfur release time according to the present invention firstly involves co-precipitation and washing according to the conventional high-temperature shift catalyst preparation route, then placing the filter cake into a reaction vessel, adding deionized water and stirring to form a slurry, followed by ultrasonic vibration, adding calcium nitrate solution, reacting for a period of time, transferring the material to a washing device, washing 3-5 times, and finally completing the catalyst preparation according to the conventional high-temperature shift catalyst preparation route. The preparation method of the present invention uses ultrasonic vibration to break up the precipitated particles, releasing trace amounts of FeSO4, Na2SO4, and K2SO4 encapsulated in the precipitated particles, which react with calcium nitrate to form insoluble calcium sulfate. Washing removes the slightly soluble calcium nitrate. In the preparation process of the high-temperature shift catalyst of the present invention, calcium nitrate is added under ultrasonic conditions, converting the FeSO4, Na2SO4, and K2SO4 contained in the catalyst into stable calcium sulfate. The generated calcium sulfate exhibits good thermal stability during the reduction and shift reaction processes of the high-temperature shift catalyst and has no adverse effects on the catalyst; the generated calcium sulfate does not react to release H2S under reduction and shift reaction conditions.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] (1) The method for preparing the high-temperature shift catalyst for shortening the sulfur release time of the present invention has good applicability and is suitable for improving various existing catalyst preparation processes, and can significantly shorten the sulfur release time.

[0022] (2) The preparation method of the high-temperature conversion catalyst for shortening sulfur release time of the present invention is simple to operate, widely adaptable, requires little process modification, and has low cost. Attached Figure Description

[0023] Figure 1 This is a process flow diagram of preparation method one of the present invention;

[0024] Figure 2 This is a process flow diagram of the second preparation method of the present invention;

[0025] Figure 3 This is a process flow diagram of preparation method three of the present invention;

[0026] Figure 4 This is a process flow diagram of preparation method four of the present invention. Detailed Implementation

[0027] The present invention will be further described below with reference to specific embodiments.

[0028] Example 1

[0029] The preparation process of Example 2 described in the existing patent CN1097483C is improved according to the preparation method of the present invention.

[0030] The method for preparing the high-temperature shift catalyst that shortens the sulfur release time includes the following steps:

[0031] Based on the production of 100g of catalyst, 344g of FeSO4·7H2O was dissolved in hot water at 30-50℃ to prepare a ferrous sulfate solution with a concentration of 130-180g / L (calculated as Fe2O3). 120g of NH4HCO3 was dissolved, and liquid ammonia was used to adjust the concentration of (NH4)2CO3 in the ammonium solution to 180-280g / L and the concentration of NH4OH to 20-100g / L. When the bottom water temperature in the reactor reached 60℃, the above ferrous sulfate solution and ammonium solution were co-precipitated in parallel, with the temperature controlled at 65-75℃, the pH value controlled at 6.5-7.5, and the reaction time controlled at approximately 30 minutes. After the reaction, the precipitate was aged at 90-95℃ for 60 minutes. The precipitate was washed 4-6 times with deionized water at 40-60℃. The washing solution was titrated with a 10% (w / w) BaCl2 solution until no white precipitate appeared, indicating the washing was complete, yielding an iron oxide slurry.

[0032] 6g of iron-aluminum-silicon composite oxide, 1.5g of vanadium oxide, 2g of magnesium oxide, and 4.5g of nickel oxide were added to an iron oxide slurry and the mixture was stirred for 30 minutes. After stirring, the material was ultrasonically vibrated at 30 kHz for 5 minutes, and then 5 mL of 0.25 mol / L calcium nitrate solution was added. After the reaction was complete, the mixture was filtered and washed to obtain a filter cake. The filter cake was dried, and then 10 mL of 5% potassium hydroxide solution was added. After ball milling for 60 minutes, the mixture was granulated, calcined at 350℃ for 120 minutes, and then 3g of graphite was added to form flakes, yielding the finished catalyst 1-1.

[0033] Comparative Example 1

[0034] A method for preparing a high-temperature shift catalyst, comprising preparing comparative catalysts 1-2 according to Example 2 described in CN1097483C.

[0035] Comparative Example 2

[0036] A method for preparing a high-temperature shift catalyst includes the following steps:

[0037] Based on the production of 100g of catalyst, 344g of FeSO4·7H2O was dissolved in hot water at 30-50℃ to prepare a ferrous sulfate solution with a concentration of 130-180g / L (calculated as Fe2O3). 120g of NH4HCO3 was dissolved, and liquid ammonia was used to adjust the concentration of (NH4)2CO3 in the ammonium solution to 180-280g / L, and the concentration of NH4OH to 20-100g / L. When the bottom water temperature in the reactor reached 60℃, the above ferrous sulfate solution and ammonium solution were co-precipitated in parallel, with the temperature controlled at 65-75℃, the pH value controlled at 6.5-7.5, and the reaction time controlled at approximately 30 minutes. After the reaction, the precipitate was aged at 90-95℃ for 60 minutes. The precipitate was washed 4-6 times with deionized water at 40-60℃. The washing solution was titrated with a 10% BaCl2 solution until no white precipitate appeared, indicating the washing was complete, yielding an iron oxide slurry.

[0038] Add 6g of iron-aluminum-silicon composite oxide, 1.5g of vanadium oxide, 2g of magnesium oxide, and 4.5g of nickel oxide to an iron oxide slurry and beat for 30 minutes. After beating, the material is ultrasonically vibrated for 5 minutes, then filtered and washed to obtain a filter cake. After drying the filter cake, add 10mL of a 5% potassium hydroxide solution, ball mill for 60 minutes, granulate, calcine at 350℃ for 120 minutes, add 3g of graphite, and precipitate to obtain the finished catalyst 1-3.

[0039] Comparative Example 3

[0040] A method for preparing a high-temperature shift catalyst includes the following steps:

[0041] Based on the production of 100g of catalyst, 344g of FeSO4·7H2O was dissolved in hot water at 30-50℃ to prepare a ferrous sulfate solution with a Fe2O3 concentration of 130-180g / L. 120g of NH4HCO3 was dissolved, and liquid ammonia was used to adjust the concentration of (NH4)2CO3 in the ammonium solution to 180-280g / L and the concentration of NH4OH to 20-100g / L. When the bottom water temperature in the reactor reached 60℃, the above ferrous sulfate solution and ammonium solution were co-precipitated in parallel, with the temperature controlled at 65-75℃, the pH value controlled at 6.5-7.5, and the reaction time controlled at approximately 30 minutes. After the reaction, the precipitate was aged at 90-95℃ for 60 minutes. The precipitate was washed 4-6 times with deionized water at 40-60℃. The washing solution was titrated with a 10% BaCl2 solution until no white precipitate appeared, indicating the washing was complete, yielding an iron oxide slurry.

[0042] Add 6g of iron-aluminum-silicon composite oxide, 1.5g of vanadium oxide, 2g of magnesium oxide, and 4.5g of nickel oxide to an iron oxide slurry and beat for 30 minutes. Add 5mL of 0.25mol / L calcium nitrate solution to the slurry, and after sufficient reaction, filter and wash to obtain a filter cake. After drying the filter cake, add 10mL of 5% potassium hydroxide solution, ball mill for 60 minutes, granulate, calcine at 350℃ for 120 minutes, add 3g of graphite and precipitate to obtain the finished catalyst 1-4.

[0043] Example 2

[0044] The preparation process of Example 1 described in the existing patent CN107649142B is improved according to the preparation method 2 of the present invention.

[0045] The method for preparing the high-temperature shift catalyst that shortens the sulfur release time includes the following steps:

[0046] Weigh out 167g FeSO4·7H2O, 10g CuSO4, 7.6g Cr2O3, and 5g TiO2, and add deionized water to prepare a solution of 0.6L Fe. 2+ The concentration is 1.0 mol·L⁻¹ -1 Solution A was prepared by weighing 100g of NaOH and adding deionized water to make 2.5L of solution with a concentration of 1.0 mol·L⁻¹. -1 Solution B was prepared by co-precipitating solution A with solution B at 50°C under stirring. The reaction temperature was maintained at 50°C for 2 hours. After precipitation, the reaction solution was heated to 75°C and oxidized for 4 hours. During precipitation and oxidation, 2 L of 20% potassium permanganate solution was added as an oxidant. After oxidation and aging, the mixture was filtered and washed with 10 L of 15% ammonia solution. After washing, the filter cake was transferred to a reaction vessel and slurried for 30 minutes. After ultrasonic vibration at 25 kHz for 5 minutes, 5 mL of 0.25 mol / L calcium nitrate solution was added. After the reaction was complete, the mixture was filtered and washed 3-5 times. The filter cake was dried at 150°C and calcined at 400°C for 5 hours to obtain a semi-finished catalyst. 2% graphite and 3% deionized water were added and the mixture was sheeted to obtain the finished catalyst 2-1.

[0047] Comparative Example 4

[0048] A method for preparing a high-temperature shift catalyst, wherein comparative catalyst 2-2 was prepared according to Example 2 described in CN107649142B.

[0049] Comparative Example 5

[0050] A method for preparing a high-temperature shift catalyst includes the following steps:

[0051] Weigh out 167g FeSO4·7H2O, 10g CuSO4, 7.6g Cr2O3, and 5g TiO2, and add deionized water to prepare a solution of 0.6L Fe. 2+ The concentration is 1.0 mol·L⁻¹ -1 Solution A was prepared by weighing 100g of NaOH and adding deionized water to make 2.5L of solution with a concentration of 1.0 mol·L⁻¹. -1 Solution B was prepared by co-precipitating solution A with solution B at 50°C under stirring. The reaction temperature was maintained at 50°C for 2 hours. After precipitation, the reaction solution was heated to 75°C and oxidized for 4 hours. During precipitation and oxidation, 2 L of 20% potassium permanganate solution was added as an oxidant. After oxidation and aging, the mixture was filtered and washed with 10 L of 15% ammonia solution. After washing, the filter cake was transferred to a reaction vessel and slurried for 30 minutes. After ultrasonic vibration for 5 minutes, it was filtered and washed 3-5 times. The filter cake was dried at 150°C and calcined at 400°C for 5 hours to obtain a semi-finished catalyst. 2% graphite and 3% deionized water were added and the mixture was sheeted to obtain the finished catalyst 2-3.

[0052] Example 3

[0053] The preparation process of Example 2 in the existing patent CN1173780C is improved according to the preparation method 3 of the present invention.

[0054] The method for preparing the high-temperature shift catalyst that shortens the sulfur release time includes the following steps:

[0055] Solution A was prepared by dissolving 400g FeSO4·7H2O, 14.6g MnSO4·H2O, and 10.6g NiSO4·6H2O in water. The Fe... 2+ The concentration of Fe2O3 was 120-150 g / L. Solution A was neutralized and precipitated with a 15% ammonia solution B under stirring and with a certain amount of air introduced. The pH was controlled to 7-8 at the end of neutralization. After neutralization, the temperature was raised to 50-80℃, and the crystal transformation of the ferric hydroxide precipitate was completed under stirring and with an appropriate amount of air introduced, taking 1-8 hours. After filtration and washing, the filter cake was transferred to a reaction vessel and slurried for 30 minutes. After ultrasonic vibration at 30 kHz for 4 minutes, 10 mL of 0.25 mol / L calcium nitrate solution was added, and the mixture was allowed to react fully before filtration and washing 3-5 times. 7.1 g Cu(NO3)·5H2O and 0.25 g KOH were added to the filter cake, mixed thoroughly, dried, granulated, calcined at 400℃ for 1 hour, and then 5% graphite was added to form flakes, yielding the finished catalyst 3-1.

[0056] Comparative Example 6

[0057] A method for preparing a high-temperature shift catalyst, wherein comparative catalyst 3-2 was prepared according to Example 2 described in CN1173780C.

[0058] Comparative Example 7

[0059] A method for preparing a high-temperature shift catalyst includes the following steps:

[0060] Solution A was prepared by dissolving 400g FeSO4·7H2O, 14.6g MnSO4·H2O, and 10.6g NiSO4·6H2O in water. The Fe... 2+ The concentration of Fe2O3 was 120-150 g / L. Solution A was neutralized and precipitated with a 15% ammonia solution B under stirring and with a certain amount of air introduced. The pH was controlled to 7-8 at the end of neutralization. After neutralization, the temperature was raised to 50-80℃, and the crystal transformation of the ferric hydroxide precipitate was completed under stirring and with an appropriate amount of air introduced, taking 1-8 hours. After filtration and washing, the filter cake was transferred to a reaction vessel and slurried for 30 minutes. Then, 10 mL of 0.25 mol / L calcium nitrate solution was added, and the mixture was allowed to react fully before filtration and washing 3-5 times. The filter cake was then mixed with 7.1 g Cu(NO3)·5H2O and 0.25 g KOH, dried, granulated, calcined at 400℃ for 1 hour, and then flaked with 5% graphite to obtain the finished catalyst 3-3.

[0061] Example 4

[0062] The fourth method for preparing the high-temperature shift catalyst that shortens the sulfur release time includes the following steps:

[0063] Weigh 323.7g Fe2(SO4)3·9H2O, 5.3g CrO3, and 5.9g Cu(NO3)22.5H2O, add 1L of deionized water to dissolve and prepare solution A. Prepare a 1mol / L NaOH solution B. Heat solution A to 70℃, and add solution B to solution A under stirring to carry out a co-precipitation reaction until pH=9. Maintain 70℃ and allow to stand for aging for 1.5h. After aging, filter and wash 5 times with 80℃ hot deionized water. Transfer the filter cake to a reactor, add deionized water, stir and slurry, ultrasonically vibrate at 40kHz for 3min, add 5mL of 0.25mol / L calcium nitrate solution, and after sufficient reaction, filter and wash 3 times. Dry the filter cake at 150℃ for 12h, calcine at 350℃ for 4h to obtain a catalyst semi-finished product. Add 2% graphite and 3% deionized water to form sheets to obtain the finished catalyst 4-1.

[0064] Comparative Example 8

[0065] A method for preparing a high-temperature shift catalyst includes the following steps:

[0066] Weigh 323.7g Fe2(SO4)3·9H2O, 5.3g CrO3, and 5.9g Cu(NO3)2·2.5H2O, add 1L of deionized water to dissolve and prepare solution A. Prepare a 1mol / L NaOH solution B. Heat solution A to 70℃, and add solution B to solution A under stirring to carry out a co-precipitation reaction until pH=9. Maintain 70℃ and allow to stand for aging for 1.5h. After aging, filter and wash 5 times with hot deionized water at 80℃. Dry the filter cake at 150℃ for 12h, and calcine at 350℃ for 4h to obtain a catalyst semi-finished product. Add 2% graphite and 3% deionized water to form sheets to obtain the finished catalyst 4-2.

[0067] evaluate

[0068] The high-temperature shift catalyst with short sulfur release time prepared in the examples and the catalyst prepared in the comparative examples were evaluated and analyzed. The results of the analysis and evaluation are shown in Table 1.

[0069] Sulfur content in the bulk: The sulfur content in the bulk was analyzed according to the HG / T 2693-2014 standard.

[0070] Catalyst activity was evaluated according to HG / T 3544-2014 standard:

[0071] The catalyst was crushed to 1.4mm-2.0mm, and 5.0ml of the catalyst was packed into a fixed-bed reactor with an inner diameter of 18mm. After the catalyst was reduced and subjected to heat resistance, its activity was evaluated.

[0072] Raw material gas composition: CO (30%), CO2 (10%), H2 (55%), N2 (5%)

[0073] Heat resistance conditions:

[0074] Catalyst bed inlet temperature: 530℃; water-to-gas ratio: 1.0; dry gas space velocity: 2000 h⁻¹ -1 ;

[0075] Heat resistance time: 15h.

[0076] After the heat resistance test is completed, the activity of the catalyst after the heat resistance test is measured.

[0077] Heat resistance evaluation conditions:

[0078] Catalyst inlet reaction temperature 350℃, 400℃; water-to-gas ratio 1.0; dry gas space velocity 2000h⁻¹ -1 .

[0079] The sulfur release process is considered complete when the H2S concentration in the exhaust gas is ≤0.2 ppm using a sulfur determination tube.

[0080] Table 1. Catalyst Evaluation and Analysis Results

[0081]

[0082]

[0083] The above analysis and evaluation results show that the sulfur content of the catalyst prepared by the improved method of the present invention is comparable to that of the catalyst prepared by the conventional method, but the sulfur release time is significantly shortened. The sulfur release is completed at the end of the reduction and no additional sulfur release time is required. The catalyst prepared by the present invention has comparable activity to the catalyst prepared by the conventional method after heat resistance, with no adverse effects.

[0084] Of course, the above description is only a preferred embodiment of the present invention and should not be considered as limiting the scope of the embodiments of the present invention. The present invention is also not limited to the above examples, and all equivalent changes and improvements made by those skilled in the art within the scope of the present invention should fall within the patent coverage of the present invention.

Claims

1. A method for the preparation of a high temperature shift catalyst with shortened sulphur lay-up time, characterized in that: The high-temperature shift catalyst raw material is prepared into a solution, and after co-precipitation reaction and washing, the filter cake is put into a reaction kettle, deionized water is added to stir and pulp, then ultrasonic oscillation is carried out, calcium nitrate solution is added, after the reaction is completed, the material is transferred to a washing device, and the filter cake after washing is extracted, dried, ball milled, granulated, roasted, and then formed into a finished catalyst by adding graphite and deionized water. The amount of calcium nitrate added is 1.3-1.8 times the theoretical sulfur content in the high-temperature shift catalyst body.

2. The method for producing a high-temperature shift catalyst with shortened sulfur deposition time according to claim 1, characterized by: The ultrasonic frequency is 25-40 KHz.

3. The method for producing a high-temperature shift catalyst with shortened sulfur deposition time according to claim 1, characterized by: The concentration of the calcium nitrate solution is 0.1-2.0 mol / L.

4. The method for producing a high-temperature shift catalyst with shortened sulfur deposition time according to claim 1, characterized by: The ammonium bicarbonate is prepared into a solution, and liquid ammonia is added to adjust it into an ammonium solution, a ferrous sulfate solution is prepared, and the ferrous sulfate solution and the ammonium solution are subjected to co-precipitation reaction in a reaction kettle, the precipitate is aged, extracted and washed, then the filter cake is put into a reaction kettle, deionized water is added to stir and pulp, an additive is added, then ultrasonic oscillation is carried out, calcium nitrate solution is added, after the reaction is completed, the material is transferred to a washing device for extraction, and the filter cake is washed 3-5 times, then potassium hydroxide solution is added after drying, ball milling, granulation, roasting, and then graphite and deionized water are added to form a high-temperature shift catalyst with short sulfur release time.

5. The method for producing a high-temperature shift catalyst with shortened sulfur-deposition time according to claim 1, characterized by: The ferrous sulfate, copper sulfate, chromic anhydride and additive salt are prepared into a mixed solution, and subjected to co-precipitation reaction with a precipitant, then an oxidizing agent is added for oxidation aging treatment after completion, the precipitate is extracted and washed, then the filter cake is put into a reaction kettle, deionized water is added to stir and pulp, then ultrasonic oscillation is carried out, calcium nitrate solution is added, after the reaction is completed, the material is transferred to a washing device, and the filter cake is washed 3-5 times, then it is dried, ball milled, granulated, roasted, and then formed into a high-temperature shift catalyst with short sulfur release time by adding graphite and deionized water.

6. The method for producing a high-temperature shift catalyst with shortened sulfur-deposition time according to claim 1, characterized by: The ferrous sulfate, manganese sulfate and nickel sulfate are dissolved in water to prepare a mixed solution, and the mixed solution is subjected to co-precipitation reaction with a precipitant solution under stirring and air inlet, and the crystal type conversion of the iron hydroxide precipitate is completed under stirring and air inlet, then the precipitate is extracted and washed, the filter cake is put into a reaction kettle, deionized water is added to stir and pulp, then ultrasonic oscillation is carried out, calcium nitrate solution is added, after the reaction is completed, the material is transferred to a washing device, and the filter cake is washed 3-5 times, then copper nitrate and potassium hydroxide solution are added after drying, ball milling, granulation and roasting, and then graphite and deionized water are added to form a high-temperature shift catalyst with short sulfur release time.

7. The method for preparing the high-temperature shift catalyst for shortening sulfur release time according to claim 1, characterized in that: The ferrous sulfate, chromic anhydride and copper nitrate are dissolved in water to prepare a solution, and subjected to co-precipitation reaction with a precipitant, then heat preservation and aging are carried out after the reaction is completed, the filter cake is extracted and washed with hot deionized water after aging is completed, then the filter cake is put into a reaction kettle, deionized water is added to stir and pulp, then ultrasonic oscillation is carried out, calcium nitrate solution is added, the material is transferred to a washing device, and the filter cake is washed 3-5 times, then a catalyst semi-product is obtained after drying and roasting, and then graphite and deionized water are added to ball mill, granulate and form, and a high-temperature shift catalyst with short sulfur release time is prepared.

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